[PATCH v2 0/7] Fix DM DAX handling

[PATCH v2 0/7] Fix DM DAX handling

[Ross Zwisler]

Changes from v1:
 * Reworked patches 1 and 2 so that the __bdev_dax_supported() function
   stays hidden behind the bdev_dax_supported() wrapper.  This is needed
   to prevent compilation errors in configs where CONFIG_FS_DAX isn't
   defined. (0-day)

 * Added Eric's Reviewed-by to patch 1.  I did this in spite of the
   bdev_dax_supported() changes because they were minor and I think
   Eric's review was focused on the XFS parts.

---

This series fixes a few issues that I found with DM's handling of DAX
devices.  Here are some of the issues I found:

 * We can create a dm-stripe or dm-linear device which is made up of an
   fsdax PMEM namespace and a raw PMEM namespace but which can hold a
   filesystem mounted with the -o dax mount option.  DAX operations to
   the raw PMEM namespace part lack struct page and can fail in
   interesting/unexpected ways when doing things like fork(), examining
   memory with gdb, etc.

 * We can create a dm-stripe or dm-linear device which is made up of an
   fsdax PMEM namespace and a BRD ramdisk which can hold a filesystem
   mounted with the -o dax mount option.  All I/O to this filesystem
   will fail.

 * In DM you can't transition a dm target which could possibly support
   DAX (mode DM_TYPE_DAX_BIO_BASED) to one which can't support DAX
   (mode DM_TYPE_BIO_BASED), even if you never use DAX.

The first 2 patches in this series are prep work from Darrick and Dave
which improve bdev_dax_supported().  The last 5 problems fix the above
mentioned problems in DM.  I feel that this series simplifies the
handling of DAX devices in DM, and the last 5 DM-related patches have a
net code reduction of 50 lines.

Darrick J. Wong (1):
  fs: allow per-device dax status checking for filesystems

Dave Jiang (1):
  dax: change bdev_dax_supported() to support boolean returns

Ross Zwisler (5):
  dm: fix test for DAX device support
  dm: prevent DAX mounts if not supported
  dm: remove DM_TYPE_DAX_BIO_BASED dm_queue_mode
  dm-snap: remove unnecessary direct_access() stub
  dm-error: remove unnecessary direct_access() stub

 drivers/dax/super.c           | 40 ++++++++++++++++++++--------------------
 drivers/md/dm-ioctl.c         | 16 ++++++----------
 drivers/md/dm-snap.c          |  8 --------
 drivers/md/dm-table.c         | 29 +++++++++++------------------
 drivers/md/dm-target.c        |  7 -------
 drivers/md/dm.c               |  7 ++-----
 fs/ext2/super.c               |  3 +--
 fs/ext4/super.c               |  3 +--
 fs/xfs/xfs_ioctl.c            |  3 ++-
 fs/xfs/xfs_iops.c             | 30 +++++++++++++++++++++++++-----
 fs/xfs/xfs_super.c            | 10 ++++++++--
 include/linux/dax.h           | 11 ++++++-----
 include/linux/device-mapper.h |  8 ++++++--
 13 files changed, 88 insertions(+), 87 deletions(-)

-- 
2.14.3

[PATCH v2 1/7] fs: allow per-device dax status checking for filesystems

[Ross Zwisler]

From: "Darrick J. Wong" <darrick.wong@oracle.com>

Change bdev_dax_supported so it takes a bdev parameter.  This enables
multi-device filesystems like xfs to check that a dax device can work for
the particular filesystem.  Once that's in place, actually fix all the
parts of XFS where we need to be able to distinguish between datadev and
rtdev.

This patch fixes the problem where we screw up the dax support checking
in xfs if the datadev and rtdev have different dax capabilities.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
[rez: Re-added __bdev_dax_supported() for !CONFIG_FS_DAX cases]
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
---
 drivers/dax/super.c | 26 +++++++++++++-------------
 fs/ext2/super.c     |  2 +-
 fs/ext4/super.c     |  2 +-
 fs/xfs/xfs_ioctl.c  |  3 ++-
 fs/xfs/xfs_iops.c   | 30 +++++++++++++++++++++++++-----
 fs/xfs/xfs_super.c  | 10 ++++++++--
 include/linux/dax.h |  9 +++++----
 7 files changed, 55 insertions(+), 27 deletions(-)

diff --git a/drivers/dax/super.c b/drivers/dax/super.c
index 2b2332b605e4..3943feb9a090 100644
--- a/drivers/dax/super.c
+++ b/drivers/dax/super.c
@@ -74,7 +74,7 @@ EXPORT_SYMBOL_GPL(fs_dax_get_by_bdev);
 
 /**
  * __bdev_dax_supported() - Check if the device supports dax for filesystem
- * @sb: The superblock of the device
+ * @bdev: block device to check
  * @blocksize: The block size of the device
  *
  * This is a library function for filesystems to check if the block device
@@ -82,33 +82,33 @@ EXPORT_SYMBOL_GPL(fs_dax_get_by_bdev);
  *
  * Return: negative errno if unsupported, 0 if supported.
  */
-int __bdev_dax_supported(struct super_block *sb, int blocksize)
+int __bdev_dax_supported(struct block_device *bdev, int blocksize)
 {
-	struct block_device *bdev = sb->s_bdev;
 	struct dax_device *dax_dev;
 	pgoff_t pgoff;
 	int err, id;
 	void *kaddr;
 	pfn_t pfn;
 	long len;
+	char buf[BDEVNAME_SIZE];
 
 	if (blocksize != PAGE_SIZE) {
-		pr_debug("VFS (%s): error: unsupported blocksize for dax\n",
-				sb->s_id);
+		pr_debug("%s: error: unsupported blocksize for dax\n",
+				bdevname(bdev, buf));
 		return -EINVAL;
 	}
 
 	err = bdev_dax_pgoff(bdev, 0, PAGE_SIZE, &pgoff);
 	if (err) {
-		pr_debug("VFS (%s): error: unaligned partition for dax\n",
-				sb->s_id);
+		pr_debug("%s: error: unaligned partition for dax\n",
+				bdevname(bdev, buf));
 		return err;
 	}
 
 	dax_dev = dax_get_by_host(bdev->bd_disk->disk_name);
 	if (!dax_dev) {
-		pr_debug("VFS (%s): error: device does not support dax\n",
-				sb->s_id);
+		pr_debug("%s: error: device does not support dax\n",
+				bdevname(bdev, buf));
 		return -EOPNOTSUPP;
 	}
 
@@ -119,8 +119,8 @@ int __bdev_dax_supported(struct super_block *sb, int blocksize)
 	put_dax(dax_dev);
 
 	if (len < 1) {
-		pr_debug("VFS (%s): error: dax access failed (%ld)\n",
-				sb->s_id, len);
+		pr_debug("%s: error: dax access failed (%ld)\n",
+				bdevname(bdev, buf), len);
 		return len < 0 ? len : -EIO;
 	}
 
@@ -137,8 +137,8 @@ int __bdev_dax_supported(struct super_block *sb, int blocksize)
 	} else if (pfn_t_devmap(pfn)) {
 		/* pass */;
 	} else {
-		pr_debug("VFS (%s): error: dax support not enabled\n",
-				sb->s_id);
+		pr_debug("%s: error: dax support not enabled\n",
+				bdevname(bdev, buf));
 		return -EOPNOTSUPP;
 	}
 
diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index de1694512f1f..9627c3054b5c 100644
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -961,7 +961,7 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent)
 	blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
 
 	if (sbi->s_mount_opt & EXT2_MOUNT_DAX) {
-		err = bdev_dax_supported(sb, blocksize);
+		err = bdev_dax_supported(sb->s_bdev, blocksize);
 		if (err) {
 			ext2_msg(sb, KERN_ERR,
 				"DAX unsupported by block device. Turning off DAX.");
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index eb104e8476f0..089170e99895 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -3732,7 +3732,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 					" that may contain inline data");
 			sbi->s_mount_opt &= ~EXT4_MOUNT_DAX;
 		}
-		err = bdev_dax_supported(sb, blocksize);
+		err = bdev_dax_supported(sb->s_bdev, blocksize);
 		if (err) {
 			ext4_msg(sb, KERN_ERR,
 				"DAX unsupported by block device. Turning off DAX.");
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 89fb1eb80aae..0effd46b965f 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -1103,7 +1103,8 @@ xfs_ioctl_setattr_dax_invalidate(
 	if (fa->fsx_xflags & FS_XFLAG_DAX) {
 		if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)))
 			return -EINVAL;
-		if (bdev_dax_supported(sb, sb->s_blocksize) < 0)
+		if (bdev_dax_supported(xfs_find_bdev_for_inode(VFS_I(ip)),
+				sb->s_blocksize) < 0)
 			return -EINVAL;
 	}
 
diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index a3ed3c811dfa..6e83acf74a95 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -1195,6 +1195,30 @@ static const struct inode_operations xfs_inline_symlink_inode_operations = {
 	.update_time		= xfs_vn_update_time,
 };
 
+/* Figure out if this file actually supports DAX. */
+static bool
+xfs_inode_supports_dax(
+	struct xfs_inode	*ip)
+{
+	struct xfs_mount	*mp = ip->i_mount;
+
+	/* Only supported on non-reflinked files. */
+	if (!S_ISREG(VFS_I(ip)->i_mode) || xfs_is_reflink_inode(ip))
+		return false;
+
+	/* DAX mount option or DAX iflag must be set. */
+	if (!(mp->m_flags & XFS_MOUNT_DAX) &&
+	    !(ip->i_d.di_flags2 & XFS_DIFLAG2_DAX))
+		return false;
+
+	/* Block size must match page size */
+	if (mp->m_sb.sb_blocksize != PAGE_SIZE)
+		return false;
+
+	/* Device has to support DAX too. */
+	return xfs_find_daxdev_for_inode(VFS_I(ip)) != NULL;
+}
+
 STATIC void
 xfs_diflags_to_iflags(
 	struct inode		*inode,
@@ -1213,11 +1237,7 @@ xfs_diflags_to_iflags(
 		inode->i_flags |= S_SYNC;
 	if (flags & XFS_DIFLAG_NOATIME)
 		inode->i_flags |= S_NOATIME;
-	if (S_ISREG(inode->i_mode) &&
-	    ip->i_mount->m_sb.sb_blocksize == PAGE_SIZE &&
-	    !xfs_is_reflink_inode(ip) &&
-	    (ip->i_mount->m_flags & XFS_MOUNT_DAX ||
-	     ip->i_d.di_flags2 & XFS_DIFLAG2_DAX))
+	if (xfs_inode_supports_dax(ip))
 		inode->i_flags |= S_DAX;
 }
 
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index d71424052917..62188c2a4c36 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -1690,11 +1690,17 @@ xfs_fs_fill_super(
 		sb->s_flags |= SB_I_VERSION;
 
 	if (mp->m_flags & XFS_MOUNT_DAX) {
+		int	error2 = 0;
+
 		xfs_warn(mp,
 		"DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
 
-		error = bdev_dax_supported(sb, sb->s_blocksize);
-		if (error) {
+		error = bdev_dax_supported(mp->m_ddev_targp->bt_bdev,
+				sb->s_blocksize);
+		if (mp->m_rtdev_targp)
+			error2 = bdev_dax_supported(mp->m_rtdev_targp->bt_bdev,
+					sb->s_blocksize);
+		if (error && error2) {
 			xfs_alert(mp,
 			"DAX unsupported by block device. Turning off DAX.");
 			mp->m_flags &= ~XFS_MOUNT_DAX;
diff --git a/include/linux/dax.h b/include/linux/dax.h
index f9eb22ad341e..2a4f7295c12b 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -64,10 +64,10 @@ static inline bool dax_write_cache_enabled(struct dax_device *dax_dev)
 struct writeback_control;
 int bdev_dax_pgoff(struct block_device *, sector_t, size_t, pgoff_t *pgoff);
 #if IS_ENABLED(CONFIG_FS_DAX)
-int __bdev_dax_supported(struct super_block *sb, int blocksize);
-static inline int bdev_dax_supported(struct super_block *sb, int blocksize)
+int __bdev_dax_supported(struct block_device *bdev, int blocksize);
+static inline int bdev_dax_supported(struct block_device *bdev, int blocksize)
 {
-	return __bdev_dax_supported(sb, blocksize);
+	return __bdev_dax_supported(bdev, blocksize);
 }
 
 static inline struct dax_device *fs_dax_get_by_host(const char *host)
@@ -84,7 +84,8 @@ struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev);
 int dax_writeback_mapping_range(struct address_space *mapping,
 		struct block_device *bdev, struct writeback_control *wbc);
 #else
-static inline int bdev_dax_supported(struct super_block *sb, int blocksize)
+static inline int bdev_dax_supported(struct block_device *bdev,
+		int blocksize)
 {
 	return -EOPNOTSUPP;
 }
-- 
2.14.3

[PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Ross Zwisler]

From: Dave Jiang <dave.jiang@intel.com>

The function return values are confusing with the way the function is
named. We expect a true or false return value but it actually returns
0/-errno.  This makes the code very confusing. Changing the return values
to return a bool where if DAX is supported then return true and no DAX
support returns false.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
---
 drivers/dax/super.c | 16 ++++++++--------
 fs/ext2/super.c     |  3 +--
 fs/ext4/super.c     |  3 +--
 fs/xfs/xfs_ioctl.c  |  4 ++--
 fs/xfs/xfs_super.c  | 12 ++++++------
 include/linux/dax.h |  8 ++++----
 6 files changed, 22 insertions(+), 24 deletions(-)

diff --git a/drivers/dax/super.c b/drivers/dax/super.c
index 3943feb9a090..1d7bd96511f0 100644
--- a/drivers/dax/super.c
+++ b/drivers/dax/super.c
@@ -80,9 +80,9 @@ EXPORT_SYMBOL_GPL(fs_dax_get_by_bdev);
  * This is a library function for filesystems to check if the block device
  * can be mounted with dax option.
  *
- * Return: negative errno if unsupported, 0 if supported.
+ * Return: true if supported, false if unsupported
  */
-int __bdev_dax_supported(struct block_device *bdev, int blocksize)
+bool __bdev_dax_supported(struct block_device *bdev, int blocksize)
 {
 	struct dax_device *dax_dev;
 	pgoff_t pgoff;
@@ -95,21 +95,21 @@ int __bdev_dax_supported(struct block_device *bdev, int blocksize)
 	if (blocksize != PAGE_SIZE) {
 		pr_debug("%s: error: unsupported blocksize for dax\n",
 				bdevname(bdev, buf));
-		return -EINVAL;
+		return false;
 	}
 
 	err = bdev_dax_pgoff(bdev, 0, PAGE_SIZE, &pgoff);
 	if (err) {
 		pr_debug("%s: error: unaligned partition for dax\n",
 				bdevname(bdev, buf));
-		return err;
+		return false;
 	}
 
 	dax_dev = dax_get_by_host(bdev->bd_disk->disk_name);
 	if (!dax_dev) {
 		pr_debug("%s: error: device does not support dax\n",
 				bdevname(bdev, buf));
-		return -EOPNOTSUPP;
+		return false;
 	}
 
 	id = dax_read_lock();
@@ -121,7 +121,7 @@ int __bdev_dax_supported(struct block_device *bdev, int blocksize)
 	if (len < 1) {
 		pr_debug("%s: error: dax access failed (%ld)\n",
 				bdevname(bdev, buf), len);
-		return len < 0 ? len : -EIO;
+		return false;
 	}
 
 	if (IS_ENABLED(CONFIG_FS_DAX_LIMITED) && pfn_t_special(pfn)) {
@@ -139,10 +139,10 @@ int __bdev_dax_supported(struct block_device *bdev, int blocksize)
 	} else {
 		pr_debug("%s: error: dax support not enabled\n",
 				bdevname(bdev, buf));
-		return -EOPNOTSUPP;
+		return false;
 	}
 
-	return 0;
+	return true;
 }
 EXPORT_SYMBOL_GPL(__bdev_dax_supported);
 #endif
diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index 9627c3054b5c..c09289a42dc5 100644
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -961,8 +961,7 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent)
 	blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
 
 	if (sbi->s_mount_opt & EXT2_MOUNT_DAX) {
-		err = bdev_dax_supported(sb->s_bdev, blocksize);
-		if (err) {
+		if (!bdev_dax_supported(sb->s_bdev, blocksize)) {
 			ext2_msg(sb, KERN_ERR,
 				"DAX unsupported by block device. Turning off DAX.");
 			sbi->s_mount_opt &= ~EXT2_MOUNT_DAX;
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 089170e99895..2e1622907f4a 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -3732,8 +3732,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 					" that may contain inline data");
 			sbi->s_mount_opt &= ~EXT4_MOUNT_DAX;
 		}
-		err = bdev_dax_supported(sb->s_bdev, blocksize);
-		if (err) {
+		if (!bdev_dax_supported(sb->s_bdev, blocksize)) {
 			ext4_msg(sb, KERN_ERR,
 				"DAX unsupported by block device. Turning off DAX.");
 			sbi->s_mount_opt &= ~EXT4_MOUNT_DAX;
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 0effd46b965f..2c70a0a4f59f 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -1103,8 +1103,8 @@ xfs_ioctl_setattr_dax_invalidate(
 	if (fa->fsx_xflags & FS_XFLAG_DAX) {
 		if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)))
 			return -EINVAL;
-		if (bdev_dax_supported(xfs_find_bdev_for_inode(VFS_I(ip)),
-				sb->s_blocksize) < 0)
+		if (!bdev_dax_supported(xfs_find_bdev_for_inode(VFS_I(ip)),
+				sb->s_blocksize))
 			return -EINVAL;
 	}
 
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 62188c2a4c36..86915dc40eed 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -1690,17 +1690,17 @@ xfs_fs_fill_super(
 		sb->s_flags |= SB_I_VERSION;
 
 	if (mp->m_flags & XFS_MOUNT_DAX) {
-		int	error2 = 0;
+		bool rtdev_is_dax = false, datadev_is_dax;
 
 		xfs_warn(mp,
 		"DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
 
-		error = bdev_dax_supported(mp->m_ddev_targp->bt_bdev,
-				sb->s_blocksize);
+		datadev_is_dax = bdev_dax_supported(mp->m_ddev_targp->bt_bdev,
+			sb->s_blocksize);
 		if (mp->m_rtdev_targp)
-			error2 = bdev_dax_supported(mp->m_rtdev_targp->bt_bdev,
-					sb->s_blocksize);
-		if (error && error2) {
+			rtdev_is_dax = bdev_dax_supported(
+				mp->m_rtdev_targp->bt_bdev, sb->s_blocksize);
+		if (!rtdev_is_dax && !datadev_is_dax) {
 			xfs_alert(mp,
 			"DAX unsupported by block device. Turning off DAX.");
 			mp->m_flags &= ~XFS_MOUNT_DAX;
diff --git a/include/linux/dax.h b/include/linux/dax.h
index 2a4f7295c12b..c99692ddd4b5 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -64,8 +64,8 @@ static inline bool dax_write_cache_enabled(struct dax_device *dax_dev)
 struct writeback_control;
 int bdev_dax_pgoff(struct block_device *, sector_t, size_t, pgoff_t *pgoff);
 #if IS_ENABLED(CONFIG_FS_DAX)
-int __bdev_dax_supported(struct block_device *bdev, int blocksize);
-static inline int bdev_dax_supported(struct block_device *bdev, int blocksize)
+bool __bdev_dax_supported(struct block_device *bdev, int blocksize);
+static inline bool bdev_dax_supported(struct block_device *bdev, int blocksize)
 {
 	return __bdev_dax_supported(bdev, blocksize);
 }
@@ -84,10 +84,10 @@ struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev);
 int dax_writeback_mapping_range(struct address_space *mapping,
 		struct block_device *bdev, struct writeback_control *wbc);
 #else
-static inline int bdev_dax_supported(struct block_device *bdev,
+static inline bool bdev_dax_supported(struct block_device *bdev,
 		int blocksize)
 {
-	return -EOPNOTSUPP;
+	return false;
 }
 
 static inline struct dax_device *fs_dax_get_by_host(const char *host)
-- 
2.14.3

Re: [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Darrick J. Wong]

On Tue, May 29, 2018 at 01:51:01PM -0600, Ross Zwisler wrote:
> From: Dave Jiang <dave.jiang@intel.com>
> 
> The function return values are confusing with the way the function is
> named. We expect a true or false return value but it actually returns
> 0/-errno.  This makes the code very confusing. Changing the return values
> to return a bool where if DAX is supported then return true and no DAX
> support returns false.
> 
> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
> Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>

Looks ok, do you want me to pull the first two patches through the xfs
tree?

Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>

--D

> ---
>  drivers/dax/super.c | 16 ++++++++--------
>  fs/ext2/super.c     |  3 +--
>  fs/ext4/super.c     |  3 +--
>  fs/xfs/xfs_ioctl.c  |  4 ++--
>  fs/xfs/xfs_super.c  | 12 ++++++------
>  include/linux/dax.h |  8 ++++----
>  6 files changed, 22 insertions(+), 24 deletions(-)
> 
> diff --git a/drivers/dax/super.c b/drivers/dax/super.c
> index 3943feb9a090..1d7bd96511f0 100644
> --- a/drivers/dax/super.c
> +++ b/drivers/dax/super.c
> @@ -80,9 +80,9 @@ EXPORT_SYMBOL_GPL(fs_dax_get_by_bdev);
>   * This is a library function for filesystems to check if the block device
>   * can be mounted with dax option.
>   *
> - * Return: negative errno if unsupported, 0 if supported.
> + * Return: true if supported, false if unsupported
>   */
> -int __bdev_dax_supported(struct block_device *bdev, int blocksize)
> +bool __bdev_dax_supported(struct block_device *bdev, int blocksize)
>  {
>  	struct dax_device *dax_dev;
>  	pgoff_t pgoff;
> @@ -95,21 +95,21 @@ int __bdev_dax_supported(struct block_device *bdev, int blocksize)
>  	if (blocksize != PAGE_SIZE) {
>  		pr_debug("%s: error: unsupported blocksize for dax\n",
>  				bdevname(bdev, buf));
> -		return -EINVAL;
> +		return false;
>  	}
>  
>  	err = bdev_dax_pgoff(bdev, 0, PAGE_SIZE, &pgoff);
>  	if (err) {
>  		pr_debug("%s: error: unaligned partition for dax\n",
>  				bdevname(bdev, buf));
> -		return err;
> +		return false;
>  	}
>  
>  	dax_dev = dax_get_by_host(bdev->bd_disk->disk_name);
>  	if (!dax_dev) {
>  		pr_debug("%s: error: device does not support dax\n",
>  				bdevname(bdev, buf));
> -		return -EOPNOTSUPP;
> +		return false;
>  	}
>  
>  	id = dax_read_lock();
> @@ -121,7 +121,7 @@ int __bdev_dax_supported(struct block_device *bdev, int blocksize)
>  	if (len < 1) {
>  		pr_debug("%s: error: dax access failed (%ld)\n",
>  				bdevname(bdev, buf), len);
> -		return len < 0 ? len : -EIO;
> +		return false;
>  	}
>  
>  	if (IS_ENABLED(CONFIG_FS_DAX_LIMITED) && pfn_t_special(pfn)) {
> @@ -139,10 +139,10 @@ int __bdev_dax_supported(struct block_device *bdev, int blocksize)
>  	} else {
>  		pr_debug("%s: error: dax support not enabled\n",
>  				bdevname(bdev, buf));
> -		return -EOPNOTSUPP;
> +		return false;
>  	}
>  
> -	return 0;
> +	return true;
>  }
>  EXPORT_SYMBOL_GPL(__bdev_dax_supported);
>  #endif
> diff --git a/fs/ext2/super.c b/fs/ext2/super.c
> index 9627c3054b5c..c09289a42dc5 100644
> --- a/fs/ext2/super.c
> +++ b/fs/ext2/super.c
> @@ -961,8 +961,7 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent)
>  	blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
>  
>  	if (sbi->s_mount_opt & EXT2_MOUNT_DAX) {
> -		err = bdev_dax_supported(sb->s_bdev, blocksize);
> -		if (err) {
> +		if (!bdev_dax_supported(sb->s_bdev, blocksize)) {
>  			ext2_msg(sb, KERN_ERR,
>  				"DAX unsupported by block device. Turning off DAX.");
>  			sbi->s_mount_opt &= ~EXT2_MOUNT_DAX;
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index 089170e99895..2e1622907f4a 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -3732,8 +3732,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
>  					" that may contain inline data");
>  			sbi->s_mount_opt &= ~EXT4_MOUNT_DAX;
>  		}
> -		err = bdev_dax_supported(sb->s_bdev, blocksize);
> -		if (err) {
> +		if (!bdev_dax_supported(sb->s_bdev, blocksize)) {
>  			ext4_msg(sb, KERN_ERR,
>  				"DAX unsupported by block device. Turning off DAX.");
>  			sbi->s_mount_opt &= ~EXT4_MOUNT_DAX;
> diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
> index 0effd46b965f..2c70a0a4f59f 100644
> --- a/fs/xfs/xfs_ioctl.c
> +++ b/fs/xfs/xfs_ioctl.c
> @@ -1103,8 +1103,8 @@ xfs_ioctl_setattr_dax_invalidate(
>  	if (fa->fsx_xflags & FS_XFLAG_DAX) {
>  		if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)))
>  			return -EINVAL;
> -		if (bdev_dax_supported(xfs_find_bdev_for_inode(VFS_I(ip)),
> -				sb->s_blocksize) < 0)
> +		if (!bdev_dax_supported(xfs_find_bdev_for_inode(VFS_I(ip)),
> +				sb->s_blocksize))
>  			return -EINVAL;
>  	}
>  
> diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
> index 62188c2a4c36..86915dc40eed 100644
> --- a/fs/xfs/xfs_super.c
> +++ b/fs/xfs/xfs_super.c
> @@ -1690,17 +1690,17 @@ xfs_fs_fill_super(
>  		sb->s_flags |= SB_I_VERSION;
>  
>  	if (mp->m_flags & XFS_MOUNT_DAX) {
> -		int	error2 = 0;
> +		bool rtdev_is_dax = false, datadev_is_dax;
>  
>  		xfs_warn(mp,
>  		"DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
>  
> -		error = bdev_dax_supported(mp->m_ddev_targp->bt_bdev,
> -				sb->s_blocksize);
> +		datadev_is_dax = bdev_dax_supported(mp->m_ddev_targp->bt_bdev,
> +			sb->s_blocksize);
>  		if (mp->m_rtdev_targp)
> -			error2 = bdev_dax_supported(mp->m_rtdev_targp->bt_bdev,
> -					sb->s_blocksize);
> -		if (error && error2) {
> +			rtdev_is_dax = bdev_dax_supported(
> +				mp->m_rtdev_targp->bt_bdev, sb->s_blocksize);
> +		if (!rtdev_is_dax && !datadev_is_dax) {
>  			xfs_alert(mp,
>  			"DAX unsupported by block device. Turning off DAX.");
>  			mp->m_flags &= ~XFS_MOUNT_DAX;
> diff --git a/include/linux/dax.h b/include/linux/dax.h
> index 2a4f7295c12b..c99692ddd4b5 100644
> --- a/include/linux/dax.h
> +++ b/include/linux/dax.h
> @@ -64,8 +64,8 @@ static inline bool dax_write_cache_enabled(struct dax_device *dax_dev)
>  struct writeback_control;
>  int bdev_dax_pgoff(struct block_device *, sector_t, size_t, pgoff_t *pgoff);
>  #if IS_ENABLED(CONFIG_FS_DAX)
> -int __bdev_dax_supported(struct block_device *bdev, int blocksize);
> -static inline int bdev_dax_supported(struct block_device *bdev, int blocksize)
> +bool __bdev_dax_supported(struct block_device *bdev, int blocksize);
> +static inline bool bdev_dax_supported(struct block_device *bdev, int blocksize)
>  {
>  	return __bdev_dax_supported(bdev, blocksize);
>  }
> @@ -84,10 +84,10 @@ struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev);
>  int dax_writeback_mapping_range(struct address_space *mapping,
>  		struct block_device *bdev, struct writeback_control *wbc);
>  #else
> -static inline int bdev_dax_supported(struct block_device *bdev,
> +static inline bool bdev_dax_supported(struct block_device *bdev,
>  		int blocksize)
>  {
> -	return -EOPNOTSUPP;
> +	return false;
>  }
>  
>  static inline struct dax_device *fs_dax_get_by_host(const char *host)
> -- 
> 2.14.3
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-xfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Ross Zwisler]

On Tue, May 29, 2018 at 02:25:10PM -0700, Darrick J. Wong wrote:
> On Tue, May 29, 2018 at 01:51:01PM -0600, Ross Zwisler wrote:
> > From: Dave Jiang <dave.jiang@intel.com>
> > 
> > The function return values are confusing with the way the function is
> > named. We expect a true or false return value but it actually returns
> > 0/-errno.  This makes the code very confusing. Changing the return values
> > to return a bool where if DAX is supported then return true and no DAX
> > support returns false.
> > 
> > Signed-off-by: Dave Jiang <dave.jiang@intel.com>
> > Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
> 
> Looks ok, do you want me to pull the first two patches through the xfs
> tree?
> 
> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>

Thanks for the review.

I'm not sure what's best.  If you do that then Mike will need to have a DM
branch for the rest of the series based on your stable commits, yea?

Mike what would you prefer?

Re: [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Darrick J. Wong]

On Tue, May 29, 2018 at 04:01:14PM -0600, Ross Zwisler wrote:
> On Tue, May 29, 2018 at 02:25:10PM -0700, Darrick J. Wong wrote:
> > On Tue, May 29, 2018 at 01:51:01PM -0600, Ross Zwisler wrote:
> > > From: Dave Jiang <dave.jiang@intel.com>
> > > 
> > > The function return values are confusing with the way the function is
> > > named. We expect a true or false return value but it actually returns
> > > 0/-errno.  This makes the code very confusing. Changing the return values
> > > to return a bool where if DAX is supported then return true and no DAX
> > > support returns false.
> > > 
> > > Signed-off-by: Dave Jiang <dave.jiang@intel.com>
> > > Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
> > 
> > Looks ok, do you want me to pull the first two patches through the xfs
> > tree?
> > 
> > Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
> 
> Thanks for the review.
> 
> I'm not sure what's best.  If you do that then Mike will need to have a DM
> branch for the rest of the series based on your stable commits, yea?
> 
> Mike what would you prefer?

I /was/ about to say that I would pull in the first two patches, but now
I can't get xfs to mount with pmem at all, and have no way of testing
this...?

# echo 'file drivers/dax/* +p' > /sys/kernel/debug/dynamic_debug/control
# mount /dev/pmem3 -o rtdev=/dev/pmem4,dax /mnt
# dmesg
<snip>
SGI XFS with ACLs, security attributes, realtime, scrub, debug enabled
XFS (pmem3): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
pmem3: error: dax support not enabled
pmem4: error: dax support not enabled
XFS (pmem3): DAX unsupported by block device. Turning off DAX.
XFS (pmem3): Mounting V5 Filesystem
XFS (pmem3): Ending clean mount

Evidently the pfn it picks up is missing PFN_MAP in flags because
ND_REGION_PAGEMAP isn't set, and looking at the kernel source, pmem that
comes in via NFIT never gets that set...?

relevant qemu pmem options:

-object memory-backend-file,id=memnvdimm0,prealloc=no,mem-path=/dev/shm/a.img,share=yes,size=13488881664
-device nvdimm,node=0,memdev=memnvdimm0,id=nvdimm0,slot=0
(repeat for five more devices)

<confused>

--D

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0000880  04  00  50  00  05  00  86  80  01  00  01  00  00  00  00  00
        004  \0   P  \0 005  \0 206 200 001  \0 001  \0  \0  \0  \0  \0
0000896  00  00  00  00  00  00  00  00  57  34  12  00  01  03  00  00
         \0  \0  \0  \0  \0  \0  \0  \0   W   4 022  \0 001 003  \0  \0
0000912  00  00  00  00  00  00  00  00  00  00  00  00  00  00  00  00
         \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0
*
0000960  00  00  38  00  06  00  03  00  00  00  00  00  00  00  00  00
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0000976  79  d3  f0  66  f3  b4  74  40  ac  43  0d  33  18  b7  8c  db
          y 323 360   f 363 264   t   @ 254   C  \r   3 030 267 214 333
0000992  00  00  00  48  07  00  00  00  00  00  00  24  03  00  00  00
         \0  \0  \0   H  \a  \0  \0  \0  \0  \0  \0   $ 003  \0  \0  \0
0001008  08  80  00  00  00  00  00  00  01  00  30  00  03  00  00  00
         \b 200  \0  \0  \0  \0  \0  \0 001  \0   0  \0 003  \0  \0  \0
0001024  00  00  00  00  06  00  07  00  00  00  00  24  03  00  00  00
         \0  \0  \0  \0 006  \0  \a  \0  \0  \0  \0   $ 003  \0  \0  \0
0001040  00  00  00  00  00  00  00  00  00  00  00  00  00  00  00  00
         \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0
0001056  00  00  01  00  00  00  00  00  04  00  50  00  07  00  86  80
         \0  \0 001  \0  \0  \0  \0  \0 004  \0   P  \0  \a  \0 206 200
0001072  01  00  01  00  00  00  00  00  00  00  00  00  00  00  00  00
        001  \0 001  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0
0001088  58  34  12  00  01  03  00  00  00  00  00  00  00  00  00  00
          X   4 022  \0 001 003  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0
0001104  00  00  00  00  00  00  00  00  00  00  00  00  00  00  00  00
         \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0
*
0001136  00  00  00  00  00  00  00  00
         \0  \0  \0  \0  \0  \0  \0  \0
0001144

> --
> To unsubscribe from this list: send the line "unsubscribe linux-xfs" in
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Re: [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Ross Zwisler]

On Thu, May 31, 2018 at 12:13:32PM -0700, Darrick J. Wong wrote:
> On Tue, May 29, 2018 at 04:01:14PM -0600, Ross Zwisler wrote:
> > On Tue, May 29, 2018 at 02:25:10PM -0700, Darrick J. Wong wrote:
> > > On Tue, May 29, 2018 at 01:51:01PM -0600, Ross Zwisler wrote:
> > > > From: Dave Jiang <dave.jiang@intel.com>
> > > > 
> > > > The function return values are confusing with the way the function is
> > > > named. We expect a true or false return value but it actually returns
> > > > 0/-errno.  This makes the code very confusing. Changing the return values
> > > > to return a bool where if DAX is supported then return true and no DAX
> > > > support returns false.
> > > > 
> > > > Signed-off-by: Dave Jiang <dave.jiang@intel.com>
> > > > Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
> > > 
> > > Looks ok, do you want me to pull the first two patches through the xfs
> > > tree?
> > > 
> > > Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
> > 
> > Thanks for the review.
> > 
> > I'm not sure what's best.  If you do that then Mike will need to have a DM
> > branch for the rest of the series based on your stable commits, yea?
> > 
> > Mike what would you prefer?
> 
> I /was/ about to say that I would pull in the first two patches, but now
> I can't get xfs to mount with pmem at all, and have no way of testing
> this...?

I'm not sure what's up - I'll dig in and find out.

Re: [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Dan Williams]

On Thu, May 31, 2018 at 12:13 PM, Darrick J. Wong
<darrick.wong@oracle.com> wrote:
> On Tue, May 29, 2018 at 04:01:14PM -0600, Ross Zwisler wrote:
>> On Tue, May 29, 2018 at 02:25:10PM -0700, Darrick J. Wong wrote:
>> > On Tue, May 29, 2018 at 01:51:01PM -0600, Ross Zwisler wrote:
>> > > From: Dave Jiang <dave.jiang@intel.com>
>> > >
>> > > The function return values are confusing with the way the function is
>> > > named. We expect a true or false return value but it actually returns
>> > > 0/-errno.  This makes the code very confusing. Changing the return values
>> > > to return a bool where if DAX is supported then return true and no DAX
>> > > support returns false.
>> > >
>> > > Signed-off-by: Dave Jiang <dave.jiang@intel.com>
>> > > Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
>> >
>> > Looks ok, do you want me to pull the first two patches through the xfs
>> > tree?
>> >
>> > Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
>>
>> Thanks for the review.
>>
>> I'm not sure what's best.  If you do that then Mike will need to have a DM
>> branch for the rest of the series based on your stable commits, yea?
>>
>> Mike what would you prefer?
>
> I /was/ about to say that I would pull in the first two patches, but now
> I can't get xfs to mount with pmem at all, and have no way of testing
> this...?
>
> # echo 'file drivers/dax/* +p' > /sys/kernel/debug/dynamic_debug/control
> # mount /dev/pmem3 -o rtdev=/dev/pmem4,dax /mnt
> # dmesg
> <snip>
> SGI XFS with ACLs, security attributes, realtime, scrub, debug enabled
> XFS (pmem3): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
> pmem3: error: dax support not enabled
> pmem4: error: dax support not enabled
> XFS (pmem3): DAX unsupported by block device. Turning off DAX.
> XFS (pmem3): Mounting V5 Filesystem
> XFS (pmem3): Ending clean mount
>
> Evidently the pfn it picks up is missing PFN_MAP in flags because
> ND_REGION_PAGEMAP isn't set, and looking at the kernel source, pmem that
> comes in via NFIT never gets that set...?
>
> relevant qemu pmem options:
>
> -object memory-backend-file,id=memnvdimm0,prealloc=no,mem-path=/dev/shm/a.img,share=yes,size=13488881664
> -device nvdimm,node=0,memdev=memnvdimm0,id=nvdimm0,slot=0
> (repeat for five more devices)
>
> <confused>
>

What does "ndctl list" say? The namespaces need to be in fsdax mode.

Re: [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Ross Zwisler]

On Thu, May 31, 2018 at 12:13:32PM -0700, Darrick J. Wong wrote:
> On Tue, May 29, 2018 at 04:01:14PM -0600, Ross Zwisler wrote:
> > On Tue, May 29, 2018 at 02:25:10PM -0700, Darrick J. Wong wrote:
> > > On Tue, May 29, 2018 at 01:51:01PM -0600, Ross Zwisler wrote:
> > > > From: Dave Jiang <dave.jiang@intel.com>
> > > > 
> > > > The function return values are confusing with the way the function is
> > > > named. We expect a true or false return value but it actually returns
> > > > 0/-errno.  This makes the code very confusing. Changing the return values
> > > > to return a bool where if DAX is supported then return true and no DAX
> > > > support returns false.
> > > > 
> > > > Signed-off-by: Dave Jiang <dave.jiang@intel.com>
> > > > Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
> > > 
> > > Looks ok, do you want me to pull the first two patches through the xfs
> > > tree?
> > > 
> > > Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
> > 
> > Thanks for the review.
> > 
> > I'm not sure what's best.  If you do that then Mike will need to have a DM
> > branch for the rest of the series based on your stable commits, yea?
> > 
> > Mike what would you prefer?
> 
> I /was/ about to say that I would pull in the first two patches, but now
> I can't get xfs to mount with pmem at all, and have no way of testing
> this...?
> 
> # echo 'file drivers/dax/* +p' > /sys/kernel/debug/dynamic_debug/control
> # mount /dev/pmem3 -o rtdev=/dev/pmem4,dax /mnt
> # dmesg
> <snip>
> SGI XFS with ACLs, security attributes, realtime, scrub, debug enabled
> XFS (pmem3): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
> pmem3: error: dax support not enabled
> pmem4: error: dax support not enabled
> XFS (pmem3): DAX unsupported by block device. Turning off DAX.
> XFS (pmem3): Mounting V5 Filesystem
> XFS (pmem3): Ending clean mount

This same sequence worked fine in my QEMU setup.

My guess is the issue is that your namespaces are in raw mode:

# ndctl list
[
  {
    "dev":"namespace1.0",
    "mode":"raw",			<< this
    "size":18119393280,
    "sector_size":512,
    "blockdev":"pmem1",
    "numa_node":0
  },
  {
    "dev":"namespace0.0",
    "mode":"raw",			<< this
    "size":18119393280,
    "sector_size":512,
    "blockdev":"pmem0",
    "numa_node":0
  }
]

If so, you can solve this by putting them in fsdax mode with ndctl:

# ndctl create-namespace -f -e namespace0.0 --mode=fsdax
{
  "dev":"namespace0.0",
  "mode":"fsdax",
  "size":"16.61 GiB (17.83 GB)",
  "uuid":"4c193c83-c031-41d4-8f96-2ff5c7b59c69",
  "raw_uuid":"2f785f09-717a-4a5e-9e9d-88d489ef1030",
  "sector_size":512,
  "blockdev":"pmem0",
  "numa_node":0
}

# ndctl create-namespace -f -e namespace1.0 --mode=fsdax
{
  "dev":"namespace1.0",
  "mode":"fsdax",
  "size":"16.61 GiB (17.83 GB)",
  "uuid":"39ec9cc4-a7ef-4f99-8354-60105543bf47",
  "raw_uuid":"403fae76-d4f8-4bed-9a3f-ef40924762be",
  "sector_size":512,
  "blockdev":"pmem1",
  "numa_node":0
}

If that doesn't fix it for you, ping me on freenode and we'll figure it out.

Thanks,
- Ross

Re: [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Mike Snitzer]

On Thu, May 31 2018 at  3:13pm -0400,
Darrick J. Wong <darrick.wong@oracle.com> wrote:

> On Tue, May 29, 2018 at 04:01:14PM -0600, Ross Zwisler wrote:
> > On Tue, May 29, 2018 at 02:25:10PM -0700, Darrick J. Wong wrote:
> > > On Tue, May 29, 2018 at 01:51:01PM -0600, Ross Zwisler wrote:
> > > > From: Dave Jiang <dave.jiang@intel.com>
> > > > 
> > > > The function return values are confusing with the way the function is
> > > > named. We expect a true or false return value but it actually returns
> > > > 0/-errno.  This makes the code very confusing. Changing the return values
> > > > to return a bool where if DAX is supported then return true and no DAX
> > > > support returns false.
> > > > 
> > > > Signed-off-by: Dave Jiang <dave.jiang@intel.com>
> > > > Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
> > > 
> > > Looks ok, do you want me to pull the first two patches through the xfs
> > > tree?
> > > 
> > > Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
> > 
> > Thanks for the review.
> > 
> > I'm not sure what's best.  If you do that then Mike will need to have a DM
> > branch for the rest of the series based on your stable commits, yea?
> > 
> > Mike what would you prefer?
> 
> I /was/ about to say that I would pull in the first two patches, but now
> I can't get xfs to mount with pmem at all, and have no way of testing
> this...?

Once you get this sorted out, please feel free to pull in the first 2.

I'm unlikely to get to reviewing the DM patches in this series until
tomorrow at the earliest.

Mike

Re: [dm-devel] [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Darrick J. Wong]

On Thu, May 31, 2018 at 04:52:06PM -0400, Mike Snitzer wrote:
> On Thu, May 31 2018 at  3:13pm -0400,
> Darrick J. Wong <darrick.wong@oracle.com> wrote:
> 
> > On Tue, May 29, 2018 at 04:01:14PM -0600, Ross Zwisler wrote:
> > > On Tue, May 29, 2018 at 02:25:10PM -0700, Darrick J. Wong wrote:
> > > > On Tue, May 29, 2018 at 01:51:01PM -0600, Ross Zwisler wrote:
> > > > > From: Dave Jiang <dave.jiang@intel.com>
> > > > > 
> > > > > The function return values are confusing with the way the function is
> > > > > named. We expect a true or false return value but it actually returns
> > > > > 0/-errno.  This makes the code very confusing. Changing the return values
> > > > > to return a bool where if DAX is supported then return true and no DAX
> > > > > support returns false.
> > > > > 
> > > > > Signed-off-by: Dave Jiang <dave.jiang@intel.com>
> > > > > Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
> > > > 
> > > > Looks ok, do you want me to pull the first two patches through the xfs
> > > > tree?
> > > > 
> > > > Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
> > > 
> > > Thanks for the review.
> > > 
> > > I'm not sure what's best.  If you do that then Mike will need to have a DM
> > > branch for the rest of the series based on your stable commits, yea?
> > > 
> > > Mike what would you prefer?
> > 
> > I /was/ about to say that I would pull in the first two patches, but now
> > I can't get xfs to mount with pmem at all, and have no way of testing
> > this...?
> 
> Once you get this sorted out, please feel free to pull in the first 2.

Sorted.  It'll be in Friday's for-next.  Ross helped me bang on the pmem
devices w/ ndctl to enable fsdax mode and twist qemu until everything
worked properly. ;)

--D

> I'm unlikely to get to reviewing the DM patches in this series until
> tomorrow at the earliest.
> 
> Mike
> 
> --
> dm-devel mailing list
> dm-devel@redhat.com
> https://www.redhat.com/mailman/listinfo/dm-devel

Re: [dm-devel] [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Ross Zwisler]

On Thu, May 31, 2018 at 03:26:45PM -0700, Darrick J. Wong wrote:
> On Thu, May 31, 2018 at 04:52:06PM -0400, Mike Snitzer wrote:
> > On Thu, May 31 2018 at  3:13pm -0400,
> > Darrick J. Wong <darrick.wong@oracle.com> wrote:
> > 
> > > On Tue, May 29, 2018 at 04:01:14PM -0600, Ross Zwisler wrote:
> > > > On Tue, May 29, 2018 at 02:25:10PM -0700, Darrick J. Wong wrote:
> > > > > On Tue, May 29, 2018 at 01:51:01PM -0600, Ross Zwisler wrote:
> > > > > > From: Dave Jiang <dave.jiang@intel.com>
> > > > > > 
> > > > > > The function return values are confusing with the way the function is
> > > > > > named. We expect a true or false return value but it actually returns
> > > > > > 0/-errno.  This makes the code very confusing. Changing the return values
> > > > > > to return a bool where if DAX is supported then return true and no DAX
> > > > > > support returns false.
> > > > > > 
> > > > > > Signed-off-by: Dave Jiang <dave.jiang@intel.com>
> > > > > > Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
> > > > > 
> > > > > Looks ok, do you want me to pull the first two patches through the xfs
> > > > > tree?
> > > > > 
> > > > > Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
> > > > 
> > > > Thanks for the review.
> > > > 
> > > > I'm not sure what's best.  If you do that then Mike will need to have a DM
> > > > branch for the rest of the series based on your stable commits, yea?
> > > > 
> > > > Mike what would you prefer?
> > > 
> > > I /was/ about to say that I would pull in the first two patches, but now
> > > I can't get xfs to mount with pmem at all, and have no way of testing
> > > this...?
> > 
> > Once you get this sorted out, please feel free to pull in the first 2.
> 
> Sorted.  It'll be in Friday's for-next.  Ross helped me bang on the pmem
> devices w/ ndctl to enable fsdax mode and twist qemu until everything
> worked properly. ;)

For anyone else who would like to simulate persistent memory using QEMU, I've
added some hints here:

https://nvdimm.wiki.kernel.org/pmem_in_qemu

Re: [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Dave Chinner]

On Thu, May 31, 2018 at 12:13:32PM -0700, Darrick J. Wong wrote:
> On Tue, May 29, 2018 at 04:01:14PM -0600, Ross Zwisler wrote:
> > On Tue, May 29, 2018 at 02:25:10PM -0700, Darrick J. Wong wrote:
> > > On Tue, May 29, 2018 at 01:51:01PM -0600, Ross Zwisler wrote:
> > > > From: Dave Jiang <dave.jiang@intel.com>
> > > > 
> > > > The function return values are confusing with the way the function is
> > > > named. We expect a true or false return value but it actually returns
> > > > 0/-errno.  This makes the code very confusing. Changing the return values
> > > > to return a bool where if DAX is supported then return true and no DAX
> > > > support returns false.
> > > > 
> > > > Signed-off-by: Dave Jiang <dave.jiang@intel.com>
> > > > Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
> > > 
> > > Looks ok, do you want me to pull the first two patches through the xfs
> > > tree?
> > > 
> > > Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
> > 
> > Thanks for the review.
> > 
> > I'm not sure what's best.  If you do that then Mike will need to have a DM
> > branch for the rest of the series based on your stable commits, yea?
> > 
> > Mike what would you prefer?
> 
> I /was/ about to say that I would pull in the first two patches, but now
> I can't get xfs to mount with pmem at all, and have no way of testing
> this...?

I have similar problems, too, but:

$ ndctl list
[
  {
    "dev":"namespace1.0",
    "mode":"raw",
    "size":8589934592,
    "sector_size":512,
    "blockdev":"pmem1"
  },
  {
    "dev":"namespace0.0",
    "mode":"raw",
    "size":8589934592,
    "sector_size":512,
    "blockdev":"pmem0"
  }
]
$ sudo ndctl create-namespace -f -e namespace0.0 --mode=fsdax
  Error: operation failed, region0 fsdax mode not available

failed to reconfigure namespace: Invalid argument
$

I can't make head or tail of what is going wrong here - how am I
supposed to debug this and get it working again?

FWIW, XFS+DAX used to just work on this setup (I hadn't even
installed ndctl until this morning!) but after changing the kernel
it no longer works. That would make it a regression, yes?

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com

Re: [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Dan Williams]

On Thu, May 31, 2018 at 6:26 PM, Dave Chinner <david@fromorbit.com> wrote:
> On Thu, May 31, 2018 at 12:13:32PM -0700, Darrick J. Wong wrote:
>> On Tue, May 29, 2018 at 04:01:14PM -0600, Ross Zwisler wrote:
>> > On Tue, May 29, 2018 at 02:25:10PM -0700, Darrick J. Wong wrote:
>> > > On Tue, May 29, 2018 at 01:51:01PM -0600, Ross Zwisler wrote:
>> > > > From: Dave Jiang <dave.jiang@intel.com>
>> > > >
>> > > > The function return values are confusing with the way the function is
>> > > > named. We expect a true or false return value but it actually returns
>> > > > 0/-errno.  This makes the code very confusing. Changing the return values
>> > > > to return a bool where if DAX is supported then return true and no DAX
>> > > > support returns false.
>> > > >
>> > > > Signed-off-by: Dave Jiang <dave.jiang@intel.com>
>> > > > Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
>> > >
>> > > Looks ok, do you want me to pull the first two patches through the xfs
>> > > tree?
>> > >
>> > > Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
>> >
>> > Thanks for the review.
>> >
>> > I'm not sure what's best.  If you do that then Mike will need to have a DM
>> > branch for the rest of the series based on your stable commits, yea?
>> >
>> > Mike what would you prefer?
>>
>> I /was/ about to say that I would pull in the first two patches, but now
>> I can't get xfs to mount with pmem at all, and have no way of testing
>> this...?
>
> I have similar problems, too, but:
>
> $ ndctl list
> [
>   {
>     "dev":"namespace1.0",
>     "mode":"raw",
>     "size":8589934592,
>     "sector_size":512,
>     "blockdev":"pmem1"
>   },
>   {
>     "dev":"namespace0.0",
>     "mode":"raw",
>     "size":8589934592,
>     "sector_size":512,
>     "blockdev":"pmem0"
>   }
> ]
> $ sudo ndctl create-namespace -f -e namespace0.0 --mode=fsdax
>   Error: operation failed, region0 fsdax mode not available
>
> failed to reconfigure namespace: Invalid argument
> $
>
> I can't make head or tail of what is going wrong here - how am I
> supposed to debug this and get it working again?
>
> FWIW, XFS+DAX used to just work on this setup (I hadn't even
> installed ndctl until this morning!) but after changing the kernel
> it no longer works. That would make it a regression, yes?

This commit caused the behavior change:

    569d0365f571 dax: require 'struct page' by default for filesystem dax

The justification is in that patch, but the short summary is we killed
off "pageless" dax because it had so many incomplete holes and
surprise behaviors. It needed to die on the path to making dax not
experimental, i.e. to close safety holes, and be feature complete for
all the ways userspace expects to use mappings (direct-io, fork,
poison handling, etc).

I suspect your kernel does not have CONFIG_ZONE_DEVICE enabled which
has the following dependencies:

        depends on MEMORY_HOTPLUG
        depends on MEMORY_HOTREMOVE
        depends on SPARSEMEM_VMEMMAP

I've created a task to go improve ndctl's error reporting for
troubleshooting this failure.

Re: [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Dave Chinner]

On Thu, May 31, 2018 at 06:57:33PM -0700, Dan Williams wrote:
> On Thu, May 31, 2018 at 6:26 PM, Dave Chinner <david@fromorbit.com> wrote:
> > On Thu, May 31, 2018 at 12:13:32PM -0700, Darrick J. Wong wrote:
> >> On Tue, May 29, 2018 at 04:01:14PM -0600, Ross Zwisler wrote:
> >> > On Tue, May 29, 2018 at 02:25:10PM -0700, Darrick J. Wong wrote:
> >> > > On Tue, May 29, 2018 at 01:51:01PM -0600, Ross Zwisler wrote:
> >> > > > From: Dave Jiang <dave.jiang@intel.com>
> >> > > >
> >> > > > The function return values are confusing with the way the function is
> >> > > > named. We expect a true or false return value but it actually returns
> >> > > > 0/-errno.  This makes the code very confusing. Changing the return values
> >> > > > to return a bool where if DAX is supported then return true and no DAX
> >> > > > support returns false.
> >> > > >
> >> > > > Signed-off-by: Dave Jiang <dave.jiang@intel.com>
> >> > > > Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
> >> > >
> >> > > Looks ok, do you want me to pull the first two patches through the xfs
> >> > > tree?
> >> > >
> >> > > Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
> >> >
> >> > Thanks for the review.
> >> >
> >> > I'm not sure what's best.  If you do that then Mike will need to have a DM
> >> > branch for the rest of the series based on your stable commits, yea?
> >> >
> >> > Mike what would you prefer?
> >>
> >> I /was/ about to say that I would pull in the first two patches, but now
> >> I can't get xfs to mount with pmem at all, and have no way of testing
> >> this...?
> >
> > I have similar problems, too, but:
> >
> > $ ndctl list
> > [
> >   {
> >     "dev":"namespace1.0",
> >     "mode":"raw",
> >     "size":8589934592,
> >     "sector_size":512,
> >     "blockdev":"pmem1"
> >   },
> >   {
> >     "dev":"namespace0.0",
> >     "mode":"raw",
> >     "size":8589934592,
> >     "sector_size":512,
> >     "blockdev":"pmem0"
> >   }
> > ]
> > $ sudo ndctl create-namespace -f -e namespace0.0 --mode=fsdax
> >   Error: operation failed, region0 fsdax mode not available
> >
> > failed to reconfigure namespace: Invalid argument
> > $
> >
> > I can't make head or tail of what is going wrong here - how am I
> > supposed to debug this and get it working again?
> >
> > FWIW, XFS+DAX used to just work on this setup (I hadn't even
> > installed ndctl until this morning!) but after changing the kernel
> > it no longer works. That would make it a regression, yes?
> 
> This commit caused the behavior change:
> 
>     569d0365f571 dax: require 'struct page' by default for filesystem dax
> 
> The justification is in that patch, but the short summary is we killed
> off "pageless" dax because it had so many incomplete holes and
> surprise behaviors. It needed to die on the path to making dax not
> experimental, i.e. to close safety holes, and be feature complete for
> all the ways userspace expects to use mappings (direct-io, fork,
> poison handling, etc).
> 
> I suspect your kernel does not have CONFIG_ZONE_DEVICE enabled which
> has the following dependencies:
> 
>         depends on MEMORY_HOTPLUG
>         depends on MEMORY_HOTREMOVE
>         depends on SPARSEMEM_VMEMMAP

Filesystem DAX now has a dependency on memory hotplug?

Fmeh. No wonder I never enabled CONFIG_ZONE_DEVICE. It's described in
menuconfig as "Device memory (pmem, HMM, etc...) hotplug support".
This isn't for hotplug support - it required for basic DAX
functionality. I've never enabled memory hotplug in any of my test
kernel configs, because the VMs I run the kernels on don't ever get
memory hotplugged....

OK, works now I've found the magic config incantantions to turn
everything I now need on.

Can we get this rationalised to a single top level config
option in the filesystems menu "Enable Filesystem DAX" that turns
on every knob that is required?

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com

Re: [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Dan Williams]

On Thu, May 31, 2018 at 7:24 PM, Dave Chinner <david@fromorbit.com> wrote:
> On Thu, May 31, 2018 at 06:57:33PM -0700, Dan Williams wrote:
>> On Thu, May 31, 2018 at 6:26 PM, Dave Chinner <david@fromorbit.com> wrote:
>> > On Thu, May 31, 2018 at 12:13:32PM -0700, Darrick J. Wong wrote:
>> >> On Tue, May 29, 2018 at 04:01:14PM -0600, Ross Zwisler wrote:
>> >> > On Tue, May 29, 2018 at 02:25:10PM -0700, Darrick J. Wong wrote:
>> >> > > On Tue, May 29, 2018 at 01:51:01PM -0600, Ross Zwisler wrote:
>> >> > > > From: Dave Jiang <dave.jiang@intel.com>
>> >> > > >
>> >> > > > The function return values are confusing with the way the function is
>> >> > > > named. We expect a true or false return value but it actually returns
>> >> > > > 0/-errno.  This makes the code very confusing. Changing the return values
>> >> > > > to return a bool where if DAX is supported then return true and no DAX
>> >> > > > support returns false.
>> >> > > >
>> >> > > > Signed-off-by: Dave Jiang <dave.jiang@intel.com>
>> >> > > > Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
>> >> > >
>> >> > > Looks ok, do you want me to pull the first two patches through the xfs
>> >> > > tree?
>> >> > >
>> >> > > Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
>> >> >
>> >> > Thanks for the review.
>> >> >
>> >> > I'm not sure what's best.  If you do that then Mike will need to have a DM
>> >> > branch for the rest of the series based on your stable commits, yea?
>> >> >
>> >> > Mike what would you prefer?
>> >>
>> >> I /was/ about to say that I would pull in the first two patches, but now
>> >> I can't get xfs to mount with pmem at all, and have no way of testing
>> >> this...?
>> >
>> > I have similar problems, too, but:
>> >
>> > $ ndctl list
>> > [
>> >   {
>> >     "dev":"namespace1.0",
>> >     "mode":"raw",
>> >     "size":8589934592,
>> >     "sector_size":512,
>> >     "blockdev":"pmem1"
>> >   },
>> >   {
>> >     "dev":"namespace0.0",
>> >     "mode":"raw",
>> >     "size":8589934592,
>> >     "sector_size":512,
>> >     "blockdev":"pmem0"
>> >   }
>> > ]
>> > $ sudo ndctl create-namespace -f -e namespace0.0 --mode=fsdax
>> >   Error: operation failed, region0 fsdax mode not available
>> >
>> > failed to reconfigure namespace: Invalid argument
>> > $
>> >
>> > I can't make head or tail of what is going wrong here - how am I
>> > supposed to debug this and get it working again?
>> >
>> > FWIW, XFS+DAX used to just work on this setup (I hadn't even
>> > installed ndctl until this morning!) but after changing the kernel
>> > it no longer works. That would make it a regression, yes?
>>
>> This commit caused the behavior change:
>>
>>     569d0365f571 dax: require 'struct page' by default for filesystem dax
>>
>> The justification is in that patch, but the short summary is we killed
>> off "pageless" dax because it had so many incomplete holes and
>> surprise behaviors. It needed to die on the path to making dax not
>> experimental, i.e. to close safety holes, and be feature complete for
>> all the ways userspace expects to use mappings (direct-io, fork,
>> poison handling, etc).
>>
>> I suspect your kernel does not have CONFIG_ZONE_DEVICE enabled which
>> has the following dependencies:
>>
>>         depends on MEMORY_HOTPLUG
>>         depends on MEMORY_HOTREMOVE
>>         depends on SPARSEMEM_VMEMMAP
>
> Filesystem DAX now has a dependency on memory hotplug?
>
> Fmeh. No wonder I never enabled CONFIG_ZONE_DEVICE. It's described in
> menuconfig as "Device memory (pmem, HMM, etc...) hotplug support".
> This isn't for hotplug support - it required for basic DAX
> functionality. I've never enabled memory hotplug in any of my test
> kernel configs, because the VMs I run the kernels on don't ever get
> memory hotplugged....
>
> OK, works now I've found the magic config incantantions to turn
> everything I now need on.
>
> Can we get this rationalised to a single top level config
> option in the filesystems menu "Enable Filesystem DAX" that turns
> on every knob that is required?

That sounds good to me. Will do.

Re: [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Dave Chinner]

On Thu, May 31, 2018 at 09:02:52PM -0700, Dan Williams wrote:
> On Thu, May 31, 2018 at 7:24 PM, Dave Chinner <david@fromorbit.com> wrote:
> > On Thu, May 31, 2018 at 06:57:33PM -0700, Dan Williams wrote:
> >> > FWIW, XFS+DAX used to just work on this setup (I hadn't even
> >> > installed ndctl until this morning!) but after changing the kernel
> >> > it no longer works. That would make it a regression, yes?

[....]

> >> I suspect your kernel does not have CONFIG_ZONE_DEVICE enabled which
> >> has the following dependencies:
> >>
> >>         depends on MEMORY_HOTPLUG
> >>         depends on MEMORY_HOTREMOVE
> >>         depends on SPARSEMEM_VMEMMAP
> >
> > Filesystem DAX now has a dependency on memory hotplug?

[....]

> > OK, works now I've found the magic config incantantions to turn
> > everything I now need on.

By enabling these options, my test VM now has a ~30s pause in the
boot very soon after the nvdimm subsystem is initialised.

[    1.523718] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
[    1.550353] 00:05: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
[    1.552175] Non-volatile memory driver v1.3
[    2.332045] tsc: Refined TSC clocksource calibration: 2199.909 MHz
[    2.333280] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x1fb5dcd4620, max_idle_ns: 440795264143 ns
[   37.217453] brd: module loaded
[   37.225423] loop: module loaded
[   37.228441] virtio_blk virtio2: [vda] 10485760 512-byte logical blocks (5.37 GB/5.00 GiB)
[   37.245418] virtio_blk virtio3: [vdb] 146800640 512-byte logical blocks (75.2 GB/70.0 GiB)
[   37.255794] virtio_blk virtio4: [vdc] 1073741824000 512-byte logical blocks (550 TB/500 TiB)
[   37.265403] nd_pmem namespace1.0: unable to guarantee persistence of writes
[   37.265618] nd_pmem namespace0.0: unable to guarantee persistence of writes

The system does not appear to be consuming CPU, but it is blocking
NMIs so I can't get a CPU trace. For a VM that I rely on booting in
a few seconds because I reboot it tens of times a day, this is a
problem....

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com

Re: [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Dave Chinner]

On Mon, Jun 04, 2018 at 08:20:38AM +1000, Dave Chinner wrote:
> On Thu, May 31, 2018 at 09:02:52PM -0700, Dan Williams wrote:
> > On Thu, May 31, 2018 at 7:24 PM, Dave Chinner <david@fromorbit.com> wrote:
> > > On Thu, May 31, 2018 at 06:57:33PM -0700, Dan Williams wrote:
> > >> > FWIW, XFS+DAX used to just work on this setup (I hadn't even
> > >> > installed ndctl until this morning!) but after changing the kernel
> > >> > it no longer works. That would make it a regression, yes?
> 
> [....]
> 
> > >> I suspect your kernel does not have CONFIG_ZONE_DEVICE enabled which
> > >> has the following dependencies:
> > >>
> > >>         depends on MEMORY_HOTPLUG
> > >>         depends on MEMORY_HOTREMOVE
> > >>         depends on SPARSEMEM_VMEMMAP
> > >
> > > Filesystem DAX now has a dependency on memory hotplug?
> 
> [....]
> 
> > > OK, works now I've found the magic config incantantions to turn
> > > everything I now need on.
> 
> By enabling these options, my test VM now has a ~30s pause in the
> boot very soon after the nvdimm subsystem is initialised.
> 
> [    1.523718] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
> [    1.550353] 00:05: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
> [    1.552175] Non-volatile memory driver v1.3
> [    2.332045] tsc: Refined TSC clocksource calibration: 2199.909 MHz
> [    2.333280] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x1fb5dcd4620, max_idle_ns: 440795264143 ns
> [   37.217453] brd: module loaded
> [   37.225423] loop: module loaded
> [   37.228441] virtio_blk virtio2: [vda] 10485760 512-byte logical blocks (5.37 GB/5.00 GiB)
> [   37.245418] virtio_blk virtio3: [vdb] 146800640 512-byte logical blocks (75.2 GB/70.0 GiB)
> [   37.255794] virtio_blk virtio4: [vdc] 1073741824000 512-byte logical blocks (550 TB/500 TiB)
> [   37.265403] nd_pmem namespace1.0: unable to guarantee persistence of writes
> [   37.265618] nd_pmem namespace0.0: unable to guarantee persistence of writes
> 
> The system does not appear to be consuming CPU, but it is blocking
> NMIs so I can't get a CPU trace. For a VM that I rely on booting in
> a few seconds because I reboot it tens of times a day, this is a
> problem....

And when I turn on KASAN, the kernel fails to boot to a login prompt
because:

[   15.363583] Non-volatile memory driver v1.3
[   22.286787] brd: module loaded
[   22.347054] loop: module loaded
[   22.352158] virtio_blk virtio2: [vda] 10485760 512-byte logical blocks (5.37 GB/5.00 GiB)
[   22.373921] virtio_blk virtio3: [vdb] 146800640 512-byte logical blocks (75.2 GB/70.0 GiB)
[   22.394363] virtio_blk virtio4: [vdc] 1073741824000 512-byte logical blocks (550 TB/500 TiB)
[   22.410145] Loading iSCSI transport class v2.0-870.
[   22.411506] nd_pmem namespace0.0: unable to guarantee persistence of writes
[   22.412777] iscsi: registered transport (tcp)
[   22.412780] megaraid cmm: 2.20.2.7 (Release Date: Sun Jul 16 00:01:03 EST 2006)
[   22.412806] nd_pmem namespace1.0: unable to guarantee persistence of writes
[   22.413090] megaraid: 2.20.5.1 (Release Date: Thu Nov 16 15:32:35 EST 2006)
[   22.421485] kworker/u33:4 (1087) used greatest stack depth: 27704 bytes left
[   22.430664] scsi host0: ata_piix
[   22.711000] BUG: unable to handle kernel paging request at ffffed0078000000
[   22.712225] PGD 13ffd1067 P4D 13ffd1067 PUD 1247d2067 PMD 0 
[   22.713180] Oops: 0000 [#1] PREEMPT SMP KASAN
[   22.713884] CPU: 8 PID: 168 Comm: kworker/u33:3 Not tainted 4.17.0-rc7-dgc+ #549
[   22.714480] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[   22.714480] Workqueue: events_unbound async_run_entry_fn
[   22.714480] RIP: 0010:check_memory_region+0xdd/0x190
[   22.714480] RSP: 0000:ffff88007a1aec08 EFLAGS: 00010202
[   22.714480] RAX: ffffed0078000000 RBX: ffff8803c0000fff RCX: ffffffff81d41a12
[   22.714480] RDX: 0000000000000000 RSI: 0000000000001000 RDI: ffff8803c0000000
[   22.714480] RBP: ffffed0078000200 R08: 0000000000000200 R09: 0000000000000040
[   22.714480] R10: 0000000000000200 R11: ffffed00780001ff R12: ffff8803c0000000
[   22.714480] R13: 000000000192f3f0 R14: 0000000000000000 R15: 0000000000000000
[   22.714480] FS:  0000000000000000(0000) GS:ffff88007f700000(0000) knlGS:0000000000000000
[   22.714480] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   22.714480] CR2: ffffed0078000000 CR3: 000000000300f001 CR4: 00000000000606e0
[   22.714480] Call Trace:
[   22.714480]  memcpy+0x1f/0x50
[   22.714480]  pmem_do_bvec+0x182/0x350
[   22.714480]  ? pmem_release_queue+0x10/0x10
[   22.714480]  ? __blkdev_get+0x484/0x7b0
[   22.714480]  ? blkdev_get+0x1e6/0x4f0
[   22.714480]  ? __device_add_disk+0x62a/0x780
[   22.714480]  ? pmem_attach_disk+0x580/0x7b0
[   22.714480]  ? do_raw_spin_unlock+0xa4/0x130
[   22.714480]  ? _raw_spin_unlock+0xa/0x20
[   22.714480]  ? create_task_io_context+0x195/0x1d0
[   22.714480]  ? generic_make_request_checks+0x33a/0x7a0
[   22.714480]  pmem_make_request+0x1d9/0x3c0
[   22.714480]  generic_make_request+0x2d8/0x6c0
[   22.714480]  ? blk_plug_queued_count+0xb0/0xb0
[   22.714480]  ? memset+0x1f/0x40
[   22.714480]  ? submit_bio+0xc8/0x1e0
[   22.714480]  submit_bio+0xc8/0x1e0
[   22.714480]  ? direct_make_request+0x150/0x150
[   22.714480]  ? alloc_buffer_head+0x3c/0x80
[   22.714480]  ? alloc_page_buffers+0x7f/0x120
[   22.714480]  ? __rcu_read_unlock+0x66/0x80
[   22.714480]  ? guard_bio_eod+0xa9/0x1e0
[   22.714480]  submit_bh_wbc.isra.41+0x257/0x280
[   22.714480]  ? end_buffer_read_nobh+0x10/0x10
[   22.714480]  block_read_full_page+0x307/0x470
[   22.714480]  ? block_llseek+0x80/0x80
[   22.714480]  ? block_page_mkwrite+0x150/0x150
[   22.714480]  ? add_to_page_cache_lru+0xd7/0x160
[   22.714480]  ? add_to_page_cache_locked+0x10/0x10
[   22.714480]  ? policy_node+0x56/0x60
[   22.714480]  do_read_cache_page+0x3e3/0x730
[   22.714480]  ? bus_probe_device+0xf3/0x120
[   22.714480]  ? async_run_entry_fn+0x75/0x1e0
[   22.714480]  ? blkdev_writepages+0x10/0x10
[   22.714480]  ? filemap_fault+0x940/0x940
[   22.714480]  ? unwind_next_frame+0x8cf/0x940
[   22.714480]  ? stack_access_ok+0x35/0x80
[   22.714480]  ? __alloc_pages_nodemask+0x18e/0x320
[   22.714480]  ? __alloc_pages_slowpath+0x12b0/0x12b0
[   22.714480]  read_dev_sector+0x61/0x120
[   22.753746] scsi host1: ata_piix
[   22.753296]  read_lba+0x260/0x2d0
[   22.753296]  ? sgi_partition+0x3c0/0x3c0
[   22.755203] ata1: PATA max MWDMA2 cmd 0x1f0 ctl 0x3f6 bmdma 0xc100 irq 14
[   22.753296]  ? do_raw_spin_unlock+0xa4/0x130
[   22.756637] ata2: PATA max MWDMA2 cmd 0x170 ctl 0x376 bmdma 0xc108 irq 15
[   22.753296]  ? is_gpt_valid.part.5+0x3c0/0x3c0
[   22.758498]  efi_partition+0x252/0xb40
[   22.758498]  ? __inc_numa_state+0x19/0x90
[   22.758498]  ? kasan_unpoison_shadow+0x30/0x40
[   22.758498]  ? vzalloc+0x58/0x60
[   22.758498]  ? rescan_partitions+0x133/0x510
[   22.758498]  ? is_gpt_valid.part.5+0x3c0/0x3c0
[   22.758498]  ? kasan_unpoison_shadow+0x30/0x40
[   22.764064]  ? get_page_from_freelist+0x16dd/0x1a50
[   22.764064]  ? widen_string+0x25/0x100
[   22.766067]  ? widen_string+0x25/0x100
[   22.766282] i8042: PNP: PS/2 Controller [PNP0303:KBD,PNP0f13:MOU] at 0x60,0x64 irq 1,12
[   22.766575]  ? string+0xc4/0xf0
[   22.766575]  ? format_decode+0x79/0x4b0
[   22.766575]  ? memcpy+0x34/0x50
[   22.770062] serio: i8042 KBD port at 0x60,0x64 irq 1
[   22.766575]  ? vsnprintf+0xf2/0x7d0
[   22.771264] serio: i8042 AUX port at 0x60,0x64 irq 12
[   22.766575]  ? num_to_str+0x160/0x160
[   22.772750]  ? __might_sleep+0x31/0xd0
[   22.773202] mousedev: PS/2 mouse device common for all mice
[   22.772750]  ? snprintf+0x8f/0xc0
[   22.772750]  ? vscnprintf+0x30/0x30
[   22.772750]  ? is_gpt_valid.part.5+0x3c0/0x3c0
[   22.776149] input: AT Translated Set 2 keyboard as /devices/platform/i8042/serio0/input/input1
[   22.776242]  ? check_partition+0x18f/0x310
[   22.776717] rtc_cmos 00:00: RTC can wake from S4
[   22.778723] rtc_cmos 00:00: registered as rtc0
[   22.779023]  check_partition+0x18f/0x310
[   22.779023]  rescan_partitions+0x133/0x510
[   22.780706] rtc_cmos 00:00: nvmem registration failed
[   22.779023]  ? __might_sleep+0x31/0xd0
[   22.782618] rtc_cmos 00:00: alarms up to one day, y3k, 114 bytes nvram, hpet irqs
[   22.779023]  ? kmem_cache_alloc+0xdd/0x5b0
[   22.779023]  ? ___might_sleep+0x7c/0x1a0
[   22.786069]  ? bd_set_size+0x104/0x160
[   22.786069]  __blkdev_get+0x484/0x7b0
[   22.786069]  ? bd_set_size+0x160/0x160
[   22.786069]  ? map_id_range_down+0x150/0x170
[   22.788981] device-mapper: ioctl: 4.39.0-ioctl (2018-04-03) initialised: dm-devel@redhat.com
[   22.786069]  ? free_user_ns+0x170/0x170
[   22.789183]  blkdev_get+0x1e6/0x4f0
[   22.789183]  ? __raw_spin_lock_init+0x42/0x50
[   22.789183]  ? __wake_up_bit+0x78/0xc0
[   22.792867] device-mapper: raid: Loading target version 1.13.2
[   22.789183]  ? __blkdev_get+0x7b0/0x7b0
[   22.789183]  ? refcount_sub_and_test+0xa7/0x120
[   22.789183]  ? refcount_inc+0x30/0x30
[   22.795220]  ? do_raw_spin_lock+0x9b/0x130
[   22.795991] hidraw: raw HID events driver (C) Jiri Kosina
[   22.796068]  ? do_raw_spin_unlock+0xa4/0x130
[   22.796068]  ? kobject_put+0x2d/0x100
[   22.796068]  __device_add_disk+0x62a/0x780
[   22.796068]  ? bdget_disk+0x50/0x50
[   22.796068]  ? alloc_dax+0x222/0x2e0
[   22.800041]  ? kill_dax+0xc0/0xc0
[   22.800041]  ? mutex_lock+0x2a/0x50
[   22.800041]  ? nvdimm_badblocks_populate+0x56/0x1d0
[   22.800041]  ? __raw_spin_lock_init+0x42/0x50
[   22.800041]  pmem_attach_disk+0x580/0x7b0
[   22.803358] oprofile: using NMI interrupt.
[   22.800041]  ? nd_pmem_notify+0x240/0x240
[   22.804217]  ? nd_dax_probe+0xef/0x110
[   22.805177] NET: Registered protocol family 17
[   22.804217]  nvdimm_bus_probe+0x76/0xe0
[   22.804217]  driver_probe_device+0x31d/0x450
[   22.806975] sctp: Hash tables configured (bind 128/128)
[   22.804217]  ? __driver_attach+0xd0/0xd0
[   22.808773] Key type dns_resolver registered
[   22.804217]  bus_for_each_drv+0xd8/0x130
[   22.809534] Key type ceph registered
[   22.804217]  ? subsys_find_device_by_id+0x1e0/0x1e0
[   22.804217]  ? do_raw_spin_unlock+0xa4/0x130
[   22.811472]  __device_attach+0x14d/0x1b0
[   22.812223]  ? device_bind_driver+0x70/0x70
[   22.812768] libceph: loaded (mon/osd proto 15/24)
[   22.812223]  ? kobject_uevent_env+0x15d/0x7f0
[   22.812223]  bus_probe_device+0xf3/0x120
[   22.812223]  device_add+0x696/0xa20
[   22.812223]  ? device_private_init+0xc0/0xc0
[   22.816158]  ? __wake_up_common_lock+0xcb/0x110
[   22.816158]  ? __wake_up_common+0x240/0x240
[   22.816158]  ? nd_async_device_unregister+0x30/0x30
[   22.816158]  nd_async_device_register+0xe/0x40
[   22.816158]  async_run_entry_fn+0x75/0x1e0
[   22.819536]  process_one_work+0x349/0x6d0
[   22.819536]  worker_thread+0x74/0x5c0
[   22.819536]  ? process_one_work+0x6d0/0x6d0
[   22.819536]  kthread+0x1b7/0x1e0
[   22.819536]  ? __kthread_bind_mask+0x70/0x70
[   22.819536]  ret_from_fork+0x24/0x30
[   22.819536] Code: 01 74 0b 41 80 38 00 74 f0 4d 85 c0 75 56 4c 01 c8 49 89 e8 49 29 c0 4d 8d 48 07 4d 85 c0 4d 0f 49 c8 49 c1 f9 03 45 85 c9 74 5b <48> 83 38 00 75 18 45 8d 41 ff 4e 8d 44 c0 08 48 8 
[   22.819536] RIP: check_memory_region+0xdd/0x190 RSP: ffff88007a1aec08
[   22.819536] CR2: ffffed0078000000
[   22.819536] ---[ end trace 2d3ad661d958a6e8 ]---
[   22.819536] BUG: sleeping function called from invalid context at ./include/linux/percpu-rwsem.h:34
[   22.819536] in_atomic(): 1, irqs_disabled(): 1, pid: 168, name: kworker/u33:3
[   22.819536] CPU: 8 PID: 168 Comm: kworker/u33:3 Tainted: G    B D           4.17.0-rc7-dgc+ #549
[   22.819536] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[   22.819536] Workqueue: events_unbound async_run_entry_fn
[   22.819536] Call Trace:
[   22.819536]  dump_stack+0x9a/0xeb
[   22.819536]  ___might_sleep+0x169/0x1a0
[   22.819536]  exit_signals+0x67/0x310
[   22.819536]  ? get_signal+0x860/0x860
[   22.819536]  ? __wake_up_common+0x240/0x240
[   22.819536]  ? nd_async_device_unregister+0x30/0x30
[   22.819536]  ? blocking_notifier_call_chain+0x24/0x70
[   22.819536]  do_exit+0x14d/0x1370
[   22.819536]  ? is_current_pgrp_orphaned+0x60/0x60
[   22.819536]  ? worker_thread+0x74/0x5c0
[   22.819536]  ? process_one_work+0x6d0/0x6d0
[   22.819536]  ? kthread+0x1b7/0x1e0
[   22.819536]  rewind_stack_do_exit+0x17/0x20
[   22.819536] ==================================================================
[   22.819536] BUG: KASAN: stack-out-of-bounds in widen_string+0x25/0x100
[   22.819536] Read of size 8 at addr ffff88007a1afae0 by task kworker/u33:3/168
[   22.819536] 
[   22.819536] CPU: 8 PID: 168 Comm: kworker/u33:3 Tainted: G      D           4.17.0-rc7-dgc+ #549
[   22.819536] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[   22.819536] Workqueue: events_unbound async_run_entry_fn
[   22.819536] Call Trace:
[   22.819536]  dump_stack+0x9a/0xeb
[   22.819536]  ? widen_string+0x25/0x100
[   22.819536]  print_address_description+0x7e/0x290
[   22.819536]  ? widen_string+0x25/0x100
[   22.819536]  kasan_report+0x237/0x360
[   22.819536]  widen_string+0x25/0x100
[   22.819536]  string+0xc4/0xf0
[   22.819536]  vsnprintf+0x2a8/0x7d0
[   22.819536]  ? num_to_str+0x160/0x160
[   22.819536]  ? subsys_find_device_by_id+0x1e0/0x1e0
[   22.819536]  ? do_raw_spin_unlock+0xa4/0x130
[   22.819536]  vscnprintf+0x9/0x30
[   22.819536]  vprintk_emit+0x86/0x400
[   22.819536]  printk+0x94/0xb0
[   22.819536]  ? cpumask_weight.constprop.27+0x1e/0x1e
[   22.819536]  ? bus_probe_device+0xf3/0x120
[   22.819536]  ? ___might_sleep+0xa7/0x1a0
[   22.819536]  ___might_sleep+0xee/0x1a0
[   22.819536]  exit_signals+0x67/0x310
[   22.819536]  ? get_signal+0x860/0x860
[   22.819536]  ? __wake_up_common+0x240/0x240
[   22.819536]  ? nd_async_device_unregister+0x30/0x30
[   22.819536]  ? blocking_notifier_call_chain+0x24/0x70
[   22.819536]  do_exit+0x14d/0x1370
[   22.819536]  ? is_current_pgrp_orphaned+0x60/0x60
[   22.819536]  ? worker_thread+0x74/0x5c0
[   22.819536]  ? process_one_work+0x6d0/0x6d0
[   22.819536]  ? kthread+0x1b7/0x1e0
[   22.819536]  rewind_stack_do_exit+0x17/0x20
[   22.819536] 
[   22.819536] The buggy address belongs to the page:
[   22.819536] page:ffffea0001ab5e48 count:0 mapcount:0 mapping:0000000000000000 index:0x0
[   22.819536] flags: 0xfffffc0000000()
[   22.819536] raw: 000fffffc0000000 0000000000000000 0000000000000000 00000000ffffffff
[   22.819536] raw: ffffea0001ab5e68 ffffea0001ab5e68 0000000000000000
[   22.819536] page dumped because: kasan: bad access detected
[   22.819536] 
[   22.819536] Memory state around the buggy address:
[   22.819536]  ffff88007a1af980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[   22.819536]  ffff88007a1afa00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1
[   22.819536] >ffff88007a1afa80: f1 f1 f1 00 00 00 00 00 00 00 00 f3 f3 f3 f3 00
[   22.819536]                                                        ^
[   22.819536]  ffff88007a1afb00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[   22.819536]  ffff88007a1afb80: 00 00 f1 f1 f1 f1 00 f2 f2 f2 f3 f3 f3 f3 f3 f3
[   22.819536] ==================================================================
[   22.882914] hpet1: lost 5 rtc interrupts
[   22.883636] note: kworker/u33:3[168] exited with preempt_count 1
[   22.885240] kworker/u33:3 (168) used greatest stack depth: 24768 bytes left
[   22.887136] BUG: unable to handle kernel paging request at ffffed00c0000000
[   22.888327] PGD 13ffd1067 P4D 13ffd1067 PUD 0 
[   22.889043] Oops: 0000 [#2] PREEMPT SMP KASAN
[   22.889747] CPU: 12 PID: 159 Comm: kworker/u33:2 Tainted: G    B D W         4.17.0-rc7-dgc+ #549
[   22.890253] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[   22.890253] Workqueue: events_unbound async_run_entry_fn
[   22.890253] RIP: 0010:check_memory_region+0xdd/0x190
[   22.890253] RSP: 0000:ffff88007a16ec08 EFLAGS: 00010202
[   22.890253] RAX: ffffed00c0000000 RBX: ffff880600000fff RCX: ffffffff81d41a12
[   22.890253] RDX: 0000000000000000 RSI: 0000000000001000 RDI: ffff880600000000
[   22.890253] RBP: ffffed00c0000200 R08: 0000000000000200 R09: 0000000000000040
[   22.890253] R10: 0000000000000200 R11: ffffed00c00001ff R12: ffff880600000000
[   22.890253] R13: 0000000001927f90 R14: 0000000000000000 R15: 0000000000000000
[   22.890253] FS:  0000000000000000(0000) GS:ffff88007f780000(0000) knlGS:0000000000000000
[   22.890253] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   22.890253] CR2: ffffed00c0000000 CR3: 000000000300f001 CR4: 00000000000606e0
[   22.890253] Call Trace:
[   22.890253]  memcpy+0x1f/0x50
[   22.890253]  pmem_do_bvec+0x182/0x350
[   22.890253]  ? pmem_release_queue+0x10/0x10
[   22.890253]  ? blkdev_get+0x1e6/0x4f0
[   22.890253]  ? __device_add_disk+0x62a/0x780
[   22.890253]  ? pmem_attach_disk+0x580/0x7b0
[   22.890253]  ? do_raw_spin_unlock+0xa4/0x130
[   22.890253]  ? _raw_spin_unlock+0xa/0x20
[   22.890253]  ? create_task_io_context+0x195/0x1d0
[   22.890253]  ? generic_make_request_checks+0x33a/0x7a0
[   22.890253]  pmem_make_request+0x1d9/0x3c0
[   22.890253]  generic_make_request+0x2d8/0x6c0
[   22.890253]  ? blk_plug_queued_count+0xb0/0xb0
[   22.890253]  ? memset+0x1f/0x40
[   22.890253]  ? submit_bio+0xc8/0x1e0
[   22.890253]  submit_bio+0xc8/0x1e0
[   22.890253]  ? direct_make_request+0x150/0x150
[   22.890253]  ? alloc_buffer_head+0x3c/0x80
[   22.890253]  ? alloc_page_buffers+0x7f/0x120
[   22.890253]  ? __rcu_read_unlock+0x66/0x80
[   22.917466] ata2.01: NODEV after polling detection
[   22.890253]  ? guard_bio_eod+0xa9/0x1e0
[   22.919184] ata1.01: NODEV after polling detection
[   22.890253]  submit_bh_wbc.isra.41+0x257/0x280
[   22.920719] ata2.00: ATAPI: QEMU DVD-ROM, 2.5+, max UDMA/100
[   22.890253]  ? end_buffer_read_nobh+0x10/0x10
[   22.922324] ata1.00: ATA-7: QEMU HARDDISK, 2.5+, max UDMA/100
[   22.890253]  block_read_full_page+0x307/0x470
[   22.923573] ata1.00: 20971520 sectors, multi 16: LBA48 
[   22.890253]  ? block_llseek+0x80/0x80
[   22.890253]  ? block_page_mkwrite+0x150/0x150
[   22.890253]  ? add_to_page_cache_lru+0xd7/0x160
[   22.890253]  ? add_to_page_cache_locked+0x10/0x10
[   22.890253]  ? policy_node+0x56/0x60
[   22.926515] ata2.00: configured for MWDMA2
[   22.890253]  do_read_cache_page+0x3e3/0x730
[   22.927886] ata1.00: configured for MWDMA2
[   22.890253]  ? bus_probe_device+0xf3/0x120
[   22.890253]  ? async_run_entry_fn+0x75/0x1e0
[   22.890253]  ? blkdev_writepages+0x10/0x10
[   22.890253]  ? filemap_fault+0x940/0x940
[   22.890253]  ? unwind_next_frame+0x8cf/0x940
[   22.890253]  ? stack_access_ok+0x35/0x80
[   22.890253]  ? deref_stack_reg+0x7f/0xb0
[   22.890253]  ? __read_once_size_nocheck.constprop.6+0x10/0x10
[   22.890253]  ? unwind_get_return_address_ptr+0x50/0x50
[   22.890253]  ? save_stack+0x89/0xb0
[   22.890253]  ? __orc_find+0x6b/0xc0
[   22.890253]  ? unwind_next_frame+0xc8/0x940
[   22.890253]  read_dev_sector+0x61/0x120
[   22.890253]  read_lba+0x260/0x2d0
[   22.890253]  ? sgi_partition+0x3c0/0x3c0
[   22.890253]  ? __save_stack_trace+0x73/0xd0
[   22.890253]  ? is_gpt_valid.part.5+0x3c0/0x3c0
[   22.890253]  efi_partition+0x252/0xb40
[   22.890253]  ? __inc_numa_state+0x19/0x90
[   22.890253]  ? kasan_unpoison_shadow+0x30/0x40
[   22.890253]  ? is_gpt_valid.part.5+0x3c0/0x3c0
[   22.890253]  ? kasan_unpoison_shadow+0x30/0x40
[   22.890253]  ? get_page_from_freelist+0x16dd/0x1a50
[   22.890253]  ? widen_string+0x25/0x100
[   22.890253]  ? widen_string+0x25/0x100
[   22.890253]  ? string+0xc4/0xf0
[   22.890253]  ? format_decode+0x79/0x4b0
[   22.890253]  ? memcpy+0x34/0x50
[   22.890253]  ? vsnprintf+0xf2/0x7d0
[   22.890253]  ? num_to_str+0x160/0x160
[   22.890253]  ? __might_sleep+0x31/0xd0
[   22.890253]  ? snprintf+0x8f/0xc0
[   22.890253]  ? vscnprintf+0x30/0x30
[   22.890253]  ? is_gpt_valid.part.5+0x3c0/0x3c0
[   22.890253]  ? check_partition+0x18f/0x310
[   22.890253]  check_partition+0x18f/0x310
[   22.890253]  rescan_partitions+0x133/0x510
[   22.890253]  ? __might_sleep+0x31/0xd0
[   22.890253]  ? ___might_sleep+0x7c/0x1a0
[   22.890253]  ? bd_set_size+0x104/0x160
[   22.890253]  __blkdev_get+0x484/0x7b0
[   22.890253]  ? __raw_spin_lock_init+0x42/0x50
[   22.890253]  ? bd_set_size+0x160/0x160
[   22.890253]  ? map_id_range_down+0x150/0x170
[   22.890253]  ? free_user_ns+0x170/0x170
[   22.890253]  blkdev_get+0x1e6/0x4f0
[   22.890253]  ? __raw_spin_lock_init+0x42/0x50
[   22.890253]  ? __wake_up_bit+0x78/0xc0
[   22.890253]  ? __blkdev_get+0x7b0/0x7b0
[   22.890253]  ? refcount_sub_and_test+0xa7/0x120
[   22.890253]  ? refcount_inc+0x30/0x30
[   22.890253]  ? do_raw_spin_lock+0x9b/0x130
[   22.890253]  ? do_raw_spin_unlock+0xa4/0x130
[   22.890253]  ? kobject_put+0x2d/0x100
[   22.890253]  __device_add_disk+0x62a/0x780
[   22.890253]  ? bdget_disk+0x50/0x50
[   22.890253]  ? alloc_dax+0x222/0x2e0
[   22.890253]  ? kill_dax+0xc0/0xc0
[   22.890253]  ? mutex_lock+0x2a/0x50
[   22.890253]  ? nvdimm_badblocks_populate+0x56/0x1d0
[   22.890253]  ? __raw_spin_lock_init+0x42/0x50
[   22.890253]  pmem_attach_disk+0x580/0x7b0
[   22.890253]  ? nd_pmem_notify+0x240/0x240
[   22.890253]  ? nd_dax_probe+0xef/0x110
[   22.890253]  nvdimm_bus_probe+0x76/0xe0
[   22.890253]  driver_probe_device+0x31d/0x450
[   22.890253]  ? __driver_attach+0xd0/0xd0
[   22.890253]  bus_for_each_drv+0xd8/0x130
[   22.890253]  ? subsys_find_device_by_id+0x1e0/0x1e0
[   22.890253]  ? do_raw_spin_unlock+0xa4/0x130
[   22.890253]  __device_attach+0x14d/0x1b0
[   22.890253]  ? device_bind_driver+0x70/0x70
[   22.890253]  ? kobject_uevent_env+0x15d/0x7f0
[   22.890253]  bus_probe_device+0xf3/0x120
[   22.890253]  device_add+0x696/0xa20
[   22.890253]  ? device_private_init+0xc0/0xc0
[   22.890253]  ? finish_task_switch+0xf8/0x3c0
[   22.890253]  ? nd_async_device_unregister+0x30/0x30
[   22.890253]  nd_async_device_register+0xe/0x40
[   22.890253]  async_run_entry_fn+0x75/0x1e0
[   22.890253]  process_one_work+0x349/0x6d0
[   22.890253]  worker_thread+0x74/0x5c0
[   22.890253]  ? process_one_work+0x6d0/0x6d0
[   22.890253]  kthread+0x1b7/0x1e0
[   22.890253]  ? __kthread_bind_mask+0x70/0x70
[   22.890253]  ret_from_fork+0x24/0x30
[   22.890253] Code: 01 74 0b 41 80 38 00 74 f0 4d 85 c0 75 56 4c 01 c8 49 89 e8 49 29 c0 4d 8d 48 07 4d 85 c0 4d 0f 49 c8 49 c1 f9 03 45 85 c9 74 5b <48> 83 38 00 75 18 45 8d 41 ff 4e 8d 44 c0 08 48 8 
[   22.890253] RIP: check_memory_region+0xdd/0x190 RSP: ffff88007a16ec08
[   22.890253] CR2: ffffed00c0000000
[   22.890253] ---[ end trace 2d3ad661d958a6e9 ]---

-Dave.
-- 
Dave Chinner
david@fromorbit.com

Re: [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Dan Williams]

On Sun, Jun 3, 2018 at 5:25 PM, Dave Chinner <david@fromorbit.com> wrote:
> On Mon, Jun 04, 2018 at 08:20:38AM +1000, Dave Chinner wrote:
>> On Thu, May 31, 2018 at 09:02:52PM -0700, Dan Williams wrote:
>> > On Thu, May 31, 2018 at 7:24 PM, Dave Chinner <david@fromorbit.com> wrote:
>> > > On Thu, May 31, 2018 at 06:57:33PM -0700, Dan Williams wrote:
>> > >> > FWIW, XFS+DAX used to just work on this setup (I hadn't even
>> > >> > installed ndctl until this morning!) but after changing the kernel
>> > >> > it no longer works. That would make it a regression, yes?
>>
>> [....]
>>
>> > >> I suspect your kernel does not have CONFIG_ZONE_DEVICE enabled which
>> > >> has the following dependencies:
>> > >>
>> > >>         depends on MEMORY_HOTPLUG
>> > >>         depends on MEMORY_HOTREMOVE
>> > >>         depends on SPARSEMEM_VMEMMAP
>> > >
>> > > Filesystem DAX now has a dependency on memory hotplug?
>>
>> [....]
>>
>> > > OK, works now I've found the magic config incantantions to turn
>> > > everything I now need on.
>>
>> By enabling these options, my test VM now has a ~30s pause in the
>> boot very soon after the nvdimm subsystem is initialised.
>>
>> [    1.523718] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
>> [    1.550353] 00:05: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
>> [    1.552175] Non-volatile memory driver v1.3
>> [    2.332045] tsc: Refined TSC clocksource calibration: 2199.909 MHz
>> [    2.333280] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x1fb5dcd4620, max_idle_ns: 440795264143 ns
>> [   37.217453] brd: module loaded
>> [   37.225423] loop: module loaded
>> [   37.228441] virtio_blk virtio2: [vda] 10485760 512-byte logical blocks (5.37 GB/5.00 GiB)
>> [   37.245418] virtio_blk virtio3: [vdb] 146800640 512-byte logical blocks (75.2 GB/70.0 GiB)
>> [   37.255794] virtio_blk virtio4: [vdc] 1073741824000 512-byte logical blocks (550 TB/500 TiB)
>> [   37.265403] nd_pmem namespace1.0: unable to guarantee persistence of writes
>> [   37.265618] nd_pmem namespace0.0: unable to guarantee persistence of writes
>>
>> The system does not appear to be consuming CPU, but it is blocking
>> NMIs so I can't get a CPU trace. For a VM that I rely on booting in
>> a few seconds because I reboot it tens of times a day, this is a
>> problem....
>
> And when I turn on KASAN, the kernel fails to boot to a login prompt
> because:

What's your qemu and kernel command line? I'll take look at this first
thing tomorrow.

Re: [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Dan Williams]

On Sun, Jun 3, 2018 at 6:48 PM, Dan Williams <dan.j.williams@intel.com> wrote:
> On Sun, Jun 3, 2018 at 5:25 PM, Dave Chinner <david@fromorbit.com> wrote:
>> On Mon, Jun 04, 2018 at 08:20:38AM +1000, Dave Chinner wrote:
>>> On Thu, May 31, 2018 at 09:02:52PM -0700, Dan Williams wrote:
>>> > On Thu, May 31, 2018 at 7:24 PM, Dave Chinner <david@fromorbit.com> wrote:
>>> > > On Thu, May 31, 2018 at 06:57:33PM -0700, Dan Williams wrote:
>>> > >> > FWIW, XFS+DAX used to just work on this setup (I hadn't even
>>> > >> > installed ndctl until this morning!) but after changing the kernel
>>> > >> > it no longer works. That would make it a regression, yes?
>>>
>>> [....]
>>>
>>> > >> I suspect your kernel does not have CONFIG_ZONE_DEVICE enabled which
>>> > >> has the following dependencies:
>>> > >>
>>> > >>         depends on MEMORY_HOTPLUG
>>> > >>         depends on MEMORY_HOTREMOVE
>>> > >>         depends on SPARSEMEM_VMEMMAP
>>> > >
>>> > > Filesystem DAX now has a dependency on memory hotplug?
>>>
>>> [....]
>>>
>>> > > OK, works now I've found the magic config incantantions to turn
>>> > > everything I now need on.
>>>
>>> By enabling these options, my test VM now has a ~30s pause in the
>>> boot very soon after the nvdimm subsystem is initialised.
>>>
>>> [    1.523718] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
>>> [    1.550353] 00:05: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
>>> [    1.552175] Non-volatile memory driver v1.3
>>> [    2.332045] tsc: Refined TSC clocksource calibration: 2199.909 MHz
>>> [    2.333280] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x1fb5dcd4620, max_idle_ns: 440795264143 ns
>>> [   37.217453] brd: module loaded
>>> [   37.225423] loop: module loaded
>>> [   37.228441] virtio_blk virtio2: [vda] 10485760 512-byte logical blocks (5.37 GB/5.00 GiB)
>>> [   37.245418] virtio_blk virtio3: [vdb] 146800640 512-byte logical blocks (75.2 GB/70.0 GiB)
>>> [   37.255794] virtio_blk virtio4: [vdc] 1073741824000 512-byte logical blocks (550 TB/500 TiB)
>>> [   37.265403] nd_pmem namespace1.0: unable to guarantee persistence of writes
>>> [   37.265618] nd_pmem namespace0.0: unable to guarantee persistence of writes
>>>
>>> The system does not appear to be consuming CPU, but it is blocking
>>> NMIs so I can't get a CPU trace. For a VM that I rely on booting in
>>> a few seconds because I reboot it tens of times a day, this is a
>>> problem....
>>
>> And when I turn on KASAN, the kernel fails to boot to a login prompt
>> because:
>
> What's your qemu and kernel command line? I'll take look at this first
> thing tomorrow.

I was able to reproduce this crash by just turning on KASAN...
investigating. It would still help to have your config for our own
regression testing purposes it makes sense for us to prioritize
"Dave's test config", similar to the priority of not breaking Linus'
laptop.

Re: [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Mike Snitzer]

On Mon, Jun 04 2018 at  7:40pm -0400,
Dan Williams <dan.j.williams@intel.com> wrote:

> On Sun, Jun 3, 2018 at 6:48 PM, Dan Williams <dan.j.williams@intel.com> wrote:
> > On Sun, Jun 3, 2018 at 5:25 PM, Dave Chinner <david@fromorbit.com> wrote:
> >> On Mon, Jun 04, 2018 at 08:20:38AM +1000, Dave Chinner wrote:
> >>> On Thu, May 31, 2018 at 09:02:52PM -0700, Dan Williams wrote:
> >>> > On Thu, May 31, 2018 at 7:24 PM, Dave Chinner <david@fromorbit.com> wrote:
> >>> > > On Thu, May 31, 2018 at 06:57:33PM -0700, Dan Williams wrote:
> >>> > >> > FWIW, XFS+DAX used to just work on this setup (I hadn't even
> >>> > >> > installed ndctl until this morning!) but after changing the kernel
> >>> > >> > it no longer works. That would make it a regression, yes?
> >>>
> >>> [....]
> >>>
> >>> > >> I suspect your kernel does not have CONFIG_ZONE_DEVICE enabled which
> >>> > >> has the following dependencies:
> >>> > >>
> >>> > >>         depends on MEMORY_HOTPLUG
> >>> > >>         depends on MEMORY_HOTREMOVE
> >>> > >>         depends on SPARSEMEM_VMEMMAP
> >>> > >
> >>> > > Filesystem DAX now has a dependency on memory hotplug?
> >>>
> >>> [....]
> >>>
> >>> > > OK, works now I've found the magic config incantantions to turn
> >>> > > everything I now need on.
> >>>
> >>> By enabling these options, my test VM now has a ~30s pause in the
> >>> boot very soon after the nvdimm subsystem is initialised.
> >>>
> >>> [    1.523718] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
> >>> [    1.550353] 00:05: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
> >>> [    1.552175] Non-volatile memory driver v1.3
> >>> [    2.332045] tsc: Refined TSC clocksource calibration: 2199.909 MHz
> >>> [    2.333280] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x1fb5dcd4620, max_idle_ns: 440795264143 ns
> >>> [   37.217453] brd: module loaded
> >>> [   37.225423] loop: module loaded
> >>> [   37.228441] virtio_blk virtio2: [vda] 10485760 512-byte logical blocks (5.37 GB/5.00 GiB)
> >>> [   37.245418] virtio_blk virtio3: [vdb] 146800640 512-byte logical blocks (75.2 GB/70.0 GiB)
> >>> [   37.255794] virtio_blk virtio4: [vdc] 1073741824000 512-byte logical blocks (550 TB/500 TiB)
> >>> [   37.265403] nd_pmem namespace1.0: unable to guarantee persistence of writes
> >>> [   37.265618] nd_pmem namespace0.0: unable to guarantee persistence of writes
> >>>
> >>> The system does not appear to be consuming CPU, but it is blocking
> >>> NMIs so I can't get a CPU trace. For a VM that I rely on booting in
> >>> a few seconds because I reboot it tens of times a day, this is a
> >>> problem....
> >>
> >> And when I turn on KASAN, the kernel fails to boot to a login prompt
> >> because:
> >
> > What's your qemu and kernel command line? I'll take look at this first
> > thing tomorrow.
> 
> I was able to reproduce this crash by just turning on KASAN...
> investigating. It would still help to have your config for our own
> regression testing purposes it makes sense for us to prioritize
> "Dave's test config", similar to the priority of not breaking Linus'
> laptop.

Dave, _this_ is when you know you've arrived! ;)

Re: [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Dave Chinner]

On Mon, Jun 04, 2018 at 08:33:26PM -0400, Mike Snitzer wrote:
> On Mon, Jun 04 2018 at  7:40pm -0400,
> Dan Williams <dan.j.williams@intel.com> wrote:
> 
> > On Sun, Jun 3, 2018 at 6:48 PM, Dan Williams <dan.j.williams@intel.com> wrote:
> > > On Sun, Jun 3, 2018 at 5:25 PM, Dave Chinner <david@fromorbit.com> wrote:
> > >> On Mon, Jun 04, 2018 at 08:20:38AM +1000, Dave Chinner wrote:
> > >>> On Thu, May 31, 2018 at 09:02:52PM -0700, Dan Williams wrote:
> > >>> > On Thu, May 31, 2018 at 7:24 PM, Dave Chinner <david@fromorbit.com> wrote:
> > >>> > > On Thu, May 31, 2018 at 06:57:33PM -0700, Dan Williams wrote:
> > >>> > >> > FWIW, XFS+DAX used to just work on this setup (I hadn't even
> > >>> > >> > installed ndctl until this morning!) but after changing the kernel
> > >>> > >> > it no longer works. That would make it a regression, yes?
> > >>>
> > >>> [....]
> > >>>
> > >>> > >> I suspect your kernel does not have CONFIG_ZONE_DEVICE enabled which
> > >>> > >> has the following dependencies:
> > >>> > >>
> > >>> > >>         depends on MEMORY_HOTPLUG
> > >>> > >>         depends on MEMORY_HOTREMOVE
> > >>> > >>         depends on SPARSEMEM_VMEMMAP
> > >>> > >
> > >>> > > Filesystem DAX now has a dependency on memory hotplug?
> > >>>
> > >>> [....]
> > >>>
> > >>> > > OK, works now I've found the magic config incantantions to turn
> > >>> > > everything I now need on.
> > >>>
> > >>> By enabling these options, my test VM now has a ~30s pause in the
> > >>> boot very soon after the nvdimm subsystem is initialised.
> > >>>
> > >>> [    1.523718] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
> > >>> [    1.550353] 00:05: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
> > >>> [    1.552175] Non-volatile memory driver v1.3
> > >>> [    2.332045] tsc: Refined TSC clocksource calibration: 2199.909 MHz
> > >>> [    2.333280] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x1fb5dcd4620, max_idle_ns: 440795264143 ns
> > >>> [   37.217453] brd: module loaded
> > >>> [   37.225423] loop: module loaded
> > >>> [   37.228441] virtio_blk virtio2: [vda] 10485760 512-byte logical blocks (5.37 GB/5.00 GiB)
> > >>> [   37.245418] virtio_blk virtio3: [vdb] 146800640 512-byte logical blocks (75.2 GB/70.0 GiB)
> > >>> [   37.255794] virtio_blk virtio4: [vdc] 1073741824000 512-byte logical blocks (550 TB/500 TiB)
> > >>> [   37.265403] nd_pmem namespace1.0: unable to guarantee persistence of writes
> > >>> [   37.265618] nd_pmem namespace0.0: unable to guarantee persistence of writes
> > >>>
> > >>> The system does not appear to be consuming CPU, but it is blocking
> > >>> NMIs so I can't get a CPU trace. For a VM that I rely on booting in
> > >>> a few seconds because I reboot it tens of times a day, this is a
> > >>> problem....
> > >>
> > >> And when I turn on KASAN, the kernel fails to boot to a login prompt
> > >> because:
> > >
> > > What's your qemu and kernel command line? I'll take look at this first
> > > thing tomorrow.
> > 
> > I was able to reproduce this crash by just turning on KASAN...
> > investigating. It would still help to have your config for our own
> > regression testing purposes it makes sense for us to prioritize
> > "Dave's test config", similar to the priority of not breaking Linus'
> > laptop.
> 
> Dave, _this_ is when you know you've arrived! ;)

Nah, this is when I know I've been a real Grouch. Someone paint
me green, hand me a garbage bin and call me Oscar. :P

I've attached the config below. At one point (probably around 3.0)
it was the barest minimum needed to boot and test XFS in a VM.  I
only tend to manually turn on the things I need for testing, but
I've never swept out stuff I don't need so who knows what crap it's
gathered over the years.

BTW, I found the init delay - it was another RNG initialisation perf
regression (this time on the fast init path) as a result of all the
OMG-THE-RNG-IS-B0RKEN changes that went into 4.17. Hint: use
/dev/urandom as the host side entropy source, not /dev/random.

That just leaves KASAN....

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com

#
# Automatically generated file; DO NOT EDIT.
# Linux/x86 4.17.0 Kernel Configuration
#
CONFIG_64BIT=y
CONFIG_X86_64=y
CONFIG_X86=y
CONFIG_INSTRUCTION_DECODER=y
CONFIG_OUTPUT_FORMAT="elf64-x86-64"
CONFIG_ARCH_DEFCONFIG="arch/x86/configs/x86_64_defconfig"
CONFIG_LOCKDEP_SUPPORT=y
CONFIG_STACKTRACE_SUPPORT=y
CONFIG_MMU=y
CONFIG_ARCH_MMAP_RND_BITS_MIN=28
CONFIG_ARCH_MMAP_RND_BITS_MAX=32
CONFIG_ARCH_MMAP_RND_COMPAT_BITS_MIN=8
CONFIG_ARCH_MMAP_RND_COMPAT_BITS_MAX=16
CONFIG_NEED_DMA_MAP_STATE=y
CONFIG_NEED_SG_DMA_LENGTH=y
CONFIG_GENERIC_ISA_DMA=y
CONFIG_GENERIC_BUG=y
CONFIG_GENERIC_BUG_RELATIVE_POINTERS=y
CONFIG_GENERIC_HWEIGHT=y
CONFIG_ARCH_MAY_HAVE_PC_FDC=y
CONFIG_RWSEM_XCHGADD_ALGORITHM=y
CONFIG_GENERIC_CALIBRATE_DELAY=y
CONFIG_ARCH_HAS_CPU_RELAX=y
CONFIG_ARCH_HAS_CACHE_LINE_SIZE=y
CONFIG_ARCH_HAS_FILTER_PGPROT=y
CONFIG_HAVE_SETUP_PER_CPU_AREA=y
CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK=y
CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK=y
CONFIG_ARCH_HIBERNATION_POSSIBLE=y
CONFIG_ARCH_SUSPEND_POSSIBLE=y
CONFIG_ARCH_WANT_HUGE_PMD_SHARE=y
CONFIG_ARCH_WANT_GENERAL_HUGETLB=y
CONFIG_ZONE_DMA32=y
CONFIG_AUDIT_ARCH=y
CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING=y
CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC=y
CONFIG_X86_64_SMP=y
CONFIG_ARCH_SUPPORTS_UPROBES=y
CONFIG_FIX_EARLYCON_MEM=y
CONFIG_PGTABLE_LEVELS=4
CONFIG_IRQ_WORK=y
CONFIG_BUILDTIME_EXTABLE_SORT=y
CONFIG_THREAD_INFO_IN_TASK=y

#
# General setup
#
CONFIG_INIT_ENV_ARG_LIMIT=32
CONFIG_CROSS_COMPILE=""
# CONFIG_COMPILE_TEST is not set
CONFIG_LOCALVERSION="-dgc"
# CONFIG_LOCALVERSION_AUTO is not set
CONFIG_HAVE_KERNEL_GZIP=y
CONFIG_HAVE_KERNEL_BZIP2=y
CONFIG_HAVE_KERNEL_LZMA=y
CONFIG_HAVE_KERNEL_XZ=y
CONFIG_HAVE_KERNEL_LZO=y
CONFIG_HAVE_KERNEL_LZ4=y
CONFIG_KERNEL_GZIP=y
# CONFIG_KERNEL_BZIP2 is not set
# CONFIG_KERNEL_LZMA is not set
# CONFIG_KERNEL_XZ is not set
# CONFIG_KERNEL_LZO is not set
# CONFIG_KERNEL_LZ4 is not set
CONFIG_DEFAULT_HOSTNAME="(none)"
CONFIG_SWAP=y
CONFIG_SYSVIPC=y
CONFIG_SYSVIPC_SYSCTL=y
CONFIG_POSIX_MQUEUE=y
CONFIG_POSIX_MQUEUE_SYSCTL=y
CONFIG_CROSS_MEMORY_ATTACH=y
CONFIG_USELIB=y
CONFIG_AUDIT=y
CONFIG_HAVE_ARCH_AUDITSYSCALL=y
CONFIG_AUDITSYSCALL=y
CONFIG_AUDIT_WATCH=y
CONFIG_AUDIT_TREE=y

#
# IRQ subsystem
#
CONFIG_GENERIC_IRQ_PROBE=y
CONFIG_GENERIC_IRQ_SHOW=y
CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK=y
CONFIG_GENERIC_PENDING_IRQ=y
CONFIG_GENERIC_IRQ_MIGRATION=y
CONFIG_IRQ_DOMAIN=y
CONFIG_IRQ_DOMAIN_HIERARCHY=y
CONFIG_GENERIC_MSI_IRQ=y
CONFIG_GENERIC_MSI_IRQ_DOMAIN=y
CONFIG_GENERIC_IRQ_MATRIX_ALLOCATOR=y
CONFIG_GENERIC_IRQ_RESERVATION_MODE=y
CONFIG_IRQ_FORCED_THREADING=y
CONFIG_SPARSE_IRQ=y
# CONFIG_GENERIC_IRQ_DEBUGFS is not set
CONFIG_CLOCKSOURCE_WATCHDOG=y
CONFIG_ARCH_CLOCKSOURCE_DATA=y
CONFIG_CLOCKSOURCE_VALIDATE_LAST_CYCLE=y
CONFIG_GENERIC_TIME_VSYSCALL=y
CONFIG_GENERIC_CLOCKEVENTS=y
CONFIG_GENERIC_CLOCKEVENTS_BROADCAST=y
CONFIG_GENERIC_CLOCKEVENTS_MIN_ADJUST=y
CONFIG_GENERIC_CMOS_UPDATE=y

#
# Timers subsystem
#
CONFIG_TICK_ONESHOT=y
CONFIG_NO_HZ_COMMON=y
# CONFIG_HZ_PERIODIC is not set
CONFIG_NO_HZ_IDLE=y
# CONFIG_NO_HZ_FULL is not set
CONFIG_NO_HZ=y
CONFIG_HIGH_RES_TIMERS=y

#
# CPU/Task time and stats accounting
#
CONFIG_VIRT_CPU_ACCOUNTING=y
# CONFIG_TICK_CPU_ACCOUNTING is not set
CONFIG_VIRT_CPU_ACCOUNTING_GEN=y
# CONFIG_IRQ_TIME_ACCOUNTING is not set
CONFIG_BSD_PROCESS_ACCT=y
# CONFIG_BSD_PROCESS_ACCT_V3 is not set
CONFIG_TASKSTATS=y
CONFIG_TASK_DELAY_ACCT=y
# CONFIG_TASK_XACCT is not set
# CONFIG_CPU_ISOLATION is not set

#
# RCU Subsystem
#
CONFIG_PREEMPT_RCU=y
# CONFIG_RCU_EXPERT is not set
CONFIG_SRCU=y
CONFIG_TREE_SRCU=y
CONFIG_TASKS_RCU=y
CONFIG_RCU_STALL_COMMON=y
CONFIG_RCU_NEED_SEGCBLIST=y
CONFIG_CONTEXT_TRACKING=y
# CONFIG_CONTEXT_TRACKING_FORCE is not set
# CONFIG_IKCONFIG is not set
CONFIG_LOG_BUF_SHIFT=23
CONFIG_LOG_CPU_MAX_BUF_SHIFT=19
CONFIG_PRINTK_SAFE_LOG_BUF_SHIFT=13
CONFIG_HAVE_UNSTABLE_SCHED_CLOCK=y
CONFIG_ARCH_SUPPORTS_NUMA_BALANCING=y
CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH=y
CONFIG_ARCH_SUPPORTS_INT128=y
CONFIG_NUMA_BALANCING=y
CONFIG_NUMA_BALANCING_DEFAULT_ENABLED=y
CONFIG_CGROUPS=y
# CONFIG_MEMCG is not set
# CONFIG_BLK_CGROUP is not set
CONFIG_CGROUP_SCHED=y
CONFIG_FAIR_GROUP_SCHED=y
# CONFIG_CFS_BANDWIDTH is not set
# CONFIG_RT_GROUP_SCHED is not set
# CONFIG_CGROUP_PIDS is not set
# CONFIG_CGROUP_RDMA is not set
CONFIG_CGROUP_FREEZER=y
# CONFIG_CGROUP_HUGETLB is not set
CONFIG_CPUSETS=y
CONFIG_PROC_PID_CPUSET=y
# CONFIG_CGROUP_DEVICE is not set
CONFIG_CGROUP_CPUACCT=y
CONFIG_CGROUP_PERF=y
# CONFIG_CGROUP_DEBUG is not set
CONFIG_NAMESPACES=y
CONFIG_UTS_NS=y
CONFIG_IPC_NS=y
CONFIG_USER_NS=y
CONFIG_PID_NS=y
CONFIG_NET_NS=y
CONFIG_SCHED_AUTOGROUP=y
CONFIG_SYSFS_DEPRECATED=y
# CONFIG_SYSFS_DEPRECATED_V2 is not set
CONFIG_RELAY=y
CONFIG_BLK_DEV_INITRD=y
CONFIG_INITRAMFS_SOURCE=""
CONFIG_RD_GZIP=y
CONFIG_RD_BZIP2=y
CONFIG_RD_LZMA=y
CONFIG_RD_XZ=y
CONFIG_RD_LZO=y
CONFIG_RD_LZ4=y
CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE=y
# CONFIG_CC_OPTIMIZE_FOR_SIZE is not set
CONFIG_SYSCTL=y
CONFIG_ANON_INODES=y
CONFIG_HAVE_UID16=y
CONFIG_SYSCTL_EXCEPTION_TRACE=y
CONFIG_HAVE_PCSPKR_PLATFORM=y
CONFIG_BPF=y
CONFIG_EXPERT=y
CONFIG_UID16=y
CONFIG_MULTIUSER=y
CONFIG_SGETMASK_SYSCALL=y
CONFIG_SYSFS_SYSCALL=y
# CONFIG_SYSCTL_SYSCALL is not set
CONFIG_FHANDLE=y
CONFIG_POSIX_TIMERS=y
CONFIG_PRINTK=y
CONFIG_PRINTK_NMI=y
CONFIG_BUG=y
CONFIG_ELF_CORE=y
CONFIG_PCSPKR_PLATFORM=y
CONFIG_BASE_FULL=y
CONFIG_FUTEX=y
CONFIG_FUTEX_PI=y
CONFIG_EPOLL=y
CONFIG_SIGNALFD=y
CONFIG_TIMERFD=y
CONFIG_EVENTFD=y
CONFIG_SHMEM=y
CONFIG_AIO=y
CONFIG_ADVISE_SYSCALLS=y
CONFIG_MEMBARRIER=y
# CONFIG_CHECKPOINT_RESTORE is not set
CONFIG_KALLSYMS=y
CONFIG_KALLSYMS_ALL=y
CONFIG_KALLSYMS_ABSOLUTE_PERCPU=y
CONFIG_KALLSYMS_BASE_RELATIVE=y
# CONFIG_BPF_SYSCALL is not set
# CONFIG_USERFAULTFD is not set
CONFIG_ARCH_HAS_MEMBARRIER_SYNC_CORE=y
# CONFIG_EMBEDDED is not set
CONFIG_HAVE_PERF_EVENTS=y
# CONFIG_PC104 is not set

#
# Kernel Performance Events And Counters
#
CONFIG_PERF_EVENTS=y
# CONFIG_DEBUG_PERF_USE_VMALLOC is not set
CONFIG_VM_EVENT_COUNTERS=y
CONFIG_COMPAT_BRK=y
CONFIG_SLAB=y
# CONFIG_SLUB is not set
# CONFIG_SLOB is not set
# CONFIG_SLAB_MERGE_DEFAULT is not set
# CONFIG_SLAB_FREELIST_RANDOM is not set
CONFIG_PROFILING=y
CONFIG_TRACEPOINTS=y
CONFIG_CRASH_CORE=y
CONFIG_KEXEC_CORE=y
CONFIG_OPROFILE=y
# CONFIG_OPROFILE_EVENT_MULTIPLEX is not set
CONFIG_HAVE_OPROFILE=y
CONFIG_OPROFILE_NMI_TIMER=y
CONFIG_JUMP_LABEL=y
# CONFIG_STATIC_KEYS_SELFTEST is not set
CONFIG_UPROBES=y
CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS=y
CONFIG_ARCH_USE_BUILTIN_BSWAP=y
CONFIG_USER_RETURN_NOTIFIER=y
CONFIG_HAVE_IOREMAP_PROT=y
CONFIG_HAVE_KPROBES=y
CONFIG_HAVE_KRETPROBES=y
CONFIG_HAVE_OPTPROBES=y
CONFIG_HAVE_KPROBES_ON_FTRACE=y
CONFIG_HAVE_FUNCTION_ERROR_INJECTION=y
CONFIG_HAVE_NMI=y
CONFIG_HAVE_ARCH_TRACEHOOK=y
CONFIG_HAVE_DMA_CONTIGUOUS=y
CONFIG_GENERIC_SMP_IDLE_THREAD=y
CONFIG_ARCH_HAS_FORTIFY_SOURCE=y
CONFIG_ARCH_HAS_SET_MEMORY=y
CONFIG_HAVE_ARCH_THREAD_STRUCT_WHITELIST=y
CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT=y
CONFIG_HAVE_REGS_AND_STACK_ACCESS_API=y
CONFIG_HAVE_CLK=y
CONFIG_HAVE_DMA_API_DEBUG=y
CONFIG_HAVE_HW_BREAKPOINT=y
CONFIG_HAVE_MIXED_BREAKPOINTS_REGS=y
CONFIG_HAVE_USER_RETURN_NOTIFIER=y
CONFIG_HAVE_PERF_EVENTS_NMI=y
CONFIG_HAVE_HARDLOCKUP_DETECTOR_PERF=y
CONFIG_HAVE_PERF_REGS=y
CONFIG_HAVE_PERF_USER_STACK_DUMP=y
CONFIG_HAVE_ARCH_JUMP_LABEL=y
CONFIG_HAVE_RCU_TABLE_FREE=y
CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG=y
CONFIG_HAVE_CMPXCHG_LOCAL=y
CONFIG_HAVE_CMPXCHG_DOUBLE=y
CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION=y
CONFIG_ARCH_WANT_OLD_COMPAT_IPC=y
CONFIG_HAVE_ARCH_SECCOMP_FILTER=y
CONFIG_SECCOMP_FILTER=y
CONFIG_HAVE_GCC_PLUGINS=y
# CONFIG_GCC_PLUGINS is not set
CONFIG_HAVE_CC_STACKPROTECTOR=y
CONFIG_CC_STACKPROTECTOR_NONE=y
# CONFIG_CC_STACKPROTECTOR_REGULAR is not set
# CONFIG_CC_STACKPROTECTOR_STRONG is not set
# CONFIG_CC_STACKPROTECTOR_AUTO is not set
CONFIG_HAVE_ARCH_WITHIN_STACK_FRAMES=y
CONFIG_HAVE_CONTEXT_TRACKING=y
CONFIG_HAVE_VIRT_CPU_ACCOUNTING_GEN=y
CONFIG_HAVE_IRQ_TIME_ACCOUNTING=y
CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE=y
CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD=y
CONFIG_HAVE_ARCH_HUGE_VMAP=y
CONFIG_HAVE_ARCH_SOFT_DIRTY=y
CONFIG_HAVE_MOD_ARCH_SPECIFIC=y
CONFIG_MODULES_USE_ELF_RELA=y
CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK=y
CONFIG_ARCH_HAS_ELF_RANDOMIZE=y
CONFIG_HAVE_ARCH_MMAP_RND_BITS=y
CONFIG_HAVE_EXIT_THREAD=y
CONFIG_ARCH_MMAP_RND_BITS=28
CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS=y
CONFIG_ARCH_MMAP_RND_COMPAT_BITS=8
CONFIG_HAVE_ARCH_COMPAT_MMAP_BASES=y
CONFIG_HAVE_COPY_THREAD_TLS=y
CONFIG_HAVE_STACK_VALIDATION=y
CONFIG_OLD_SIGSUSPEND3=y
CONFIG_COMPAT_OLD_SIGACTION=y
CONFIG_HAVE_ARCH_VMAP_STACK=y
CONFIG_VMAP_STACK=y
CONFIG_ARCH_HAS_STRICT_KERNEL_RWX=y
CONFIG_STRICT_KERNEL_RWX=y
CONFIG_ARCH_HAS_STRICT_MODULE_RWX=y
CONFIG_ARCH_HAS_REFCOUNT=y
CONFIG_REFCOUNT_FULL=y

#
# GCOV-based kernel profiling
#
# CONFIG_GCOV_KERNEL is not set
CONFIG_ARCH_HAS_GCOV_PROFILE_ALL=y
CONFIG_RT_MUTEXES=y
CONFIG_BASE_SMALL=0
# CONFIG_MODULES is not set
CONFIG_MODULES_TREE_LOOKUP=y
CONFIG_BLOCK=y
CONFIG_BLK_SCSI_REQUEST=y
CONFIG_BLK_DEV_BSG=y
CONFIG_BLK_DEV_BSGLIB=y
CONFIG_BLK_DEV_INTEGRITY=y
CONFIG_BLK_DEV_ZONED=y
# CONFIG_BLK_CMDLINE_PARSER is not set
CONFIG_BLK_WBT=y
# CONFIG_BLK_WBT_SQ is not set
CONFIG_BLK_WBT_MQ=y
CONFIG_BLK_DEBUG_FS=y
# CONFIG_BLK_SED_OPAL is not set

#
# Partition Types
#
CONFIG_PARTITION_ADVANCED=y
# CONFIG_ACORN_PARTITION is not set
# CONFIG_AIX_PARTITION is not set
# CONFIG_OSF_PARTITION is not set
# CONFIG_AMIGA_PARTITION is not set
# CONFIG_ATARI_PARTITION is not set
# CONFIG_MAC_PARTITION is not set
CONFIG_MSDOS_PARTITION=y
CONFIG_BSD_DISKLABEL=y
CONFIG_MINIX_SUBPARTITION=y
CONFIG_SOLARIS_X86_PARTITION=y
CONFIG_UNIXWARE_DISKLABEL=y
# CONFIG_LDM_PARTITION is not set
CONFIG_SGI_PARTITION=y
# CONFIG_ULTRIX_PARTITION is not set
# CONFIG_SUN_PARTITION is not set
# CONFIG_KARMA_PARTITION is not set
CONFIG_EFI_PARTITION=y
# CONFIG_SYSV68_PARTITION is not set
# CONFIG_CMDLINE_PARTITION is not set
CONFIG_BLOCK_COMPAT=y
CONFIG_BLK_MQ_PCI=y
CONFIG_BLK_MQ_VIRTIO=y

#
# IO Schedulers
#
CONFIG_IOSCHED_NOOP=y
# CONFIG_IOSCHED_DEADLINE is not set
# CONFIG_IOSCHED_CFQ is not set
CONFIG_DEFAULT_NOOP=y
CONFIG_DEFAULT_IOSCHED="noop"
CONFIG_MQ_IOSCHED_DEADLINE=y
CONFIG_MQ_IOSCHED_KYBER=y
CONFIG_IOSCHED_BFQ=y
CONFIG_PREEMPT_NOTIFIERS=y
CONFIG_UNINLINE_SPIN_UNLOCK=y
CONFIG_ARCH_SUPPORTS_ATOMIC_RMW=y
CONFIG_MUTEX_SPIN_ON_OWNER=y
CONFIG_RWSEM_SPIN_ON_OWNER=y
CONFIG_LOCK_SPIN_ON_OWNER=y
CONFIG_ARCH_USE_QUEUED_SPINLOCKS=y
CONFIG_QUEUED_SPINLOCKS=y
CONFIG_ARCH_USE_QUEUED_RWLOCKS=y
CONFIG_QUEUED_RWLOCKS=y
CONFIG_ARCH_HAS_SYNC_CORE_BEFORE_USERMODE=y
CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y
CONFIG_FREEZER=y

#
# Processor type and features
#
CONFIG_ZONE_DMA=y
CONFIG_SMP=y
CONFIG_X86_FEATURE_NAMES=y
CONFIG_X86_X2APIC=y
CONFIG_X86_MPPARSE=y
# CONFIG_GOLDFISH is not set
# CONFIG_RETPOLINE is not set
# CONFIG_INTEL_RDT is not set
# CONFIG_X86_EXTENDED_PLATFORM is not set
# CONFIG_X86_INTEL_LPSS is not set
# CONFIG_X86_AMD_PLATFORM_DEVICE is not set
CONFIG_IOSF_MBI=y
# CONFIG_IOSF_MBI_DEBUG is not set
CONFIG_X86_SUPPORTS_MEMORY_FAILURE=y
CONFIG_SCHED_OMIT_FRAME_POINTER=y
CONFIG_HYPERVISOR_GUEST=y
CONFIG_PARAVIRT=y
# CONFIG_PARAVIRT_DEBUG is not set
CONFIG_PARAVIRT_SPINLOCKS=y
# CONFIG_QUEUED_LOCK_STAT is not set
# CONFIG_XEN is not set
CONFIG_KVM_GUEST=y
# CONFIG_KVM_DEBUG_FS is not set
CONFIG_PARAVIRT_TIME_ACCOUNTING=y
CONFIG_PARAVIRT_CLOCK=y
# CONFIG_JAILHOUSE_GUEST is not set
CONFIG_NO_BOOTMEM=y
# CONFIG_MK8 is not set
# CONFIG_MPSC is not set
CONFIG_MCORE2=y
# CONFIG_MATOM is not set
# CONFIG_GENERIC_CPU is not set
CONFIG_X86_INTERNODE_CACHE_SHIFT=6
CONFIG_X86_L1_CACHE_SHIFT=6
CONFIG_X86_INTEL_USERCOPY=y
CONFIG_X86_USE_PPRO_CHECKSUM=y
CONFIG_X86_P6_NOP=y
CONFIG_X86_TSC=y
CONFIG_X86_CMPXCHG64=y
CONFIG_X86_CMOV=y
CONFIG_X86_MINIMUM_CPU_FAMILY=64
CONFIG_X86_DEBUGCTLMSR=y
# CONFIG_PROCESSOR_SELECT is not set
CONFIG_CPU_SUP_INTEL=y
CONFIG_CPU_SUP_AMD=y
CONFIG_CPU_SUP_CENTAUR=y
CONFIG_HPET_TIMER=y
CONFIG_HPET_EMULATE_RTC=y
CONFIG_DMI=y
CONFIG_GART_IOMMU=y
# CONFIG_CALGARY_IOMMU is not set
CONFIG_SWIOTLB=y
CONFIG_IOMMU_HELPER=y
CONFIG_MAXSMP=y
CONFIG_NR_CPUS_RANGE_BEGIN=8192
CONFIG_NR_CPUS_RANGE_END=8192
CONFIG_NR_CPUS_DEFAULT=8192
CONFIG_NR_CPUS=8192
CONFIG_SCHED_SMT=y
CONFIG_SCHED_MC=y
CONFIG_SCHED_MC_PRIO=y
# CONFIG_PREEMPT_NONE is not set
# CONFIG_PREEMPT_VOLUNTARY is not set
CONFIG_PREEMPT=y
CONFIG_PREEMPT_COUNT=y
CONFIG_X86_LOCAL_APIC=y
CONFIG_X86_IO_APIC=y
CONFIG_X86_REROUTE_FOR_BROKEN_BOOT_IRQS=y
CONFIG_X86_MCE=y
# CONFIG_X86_MCELOG_LEGACY is not set
CONFIG_X86_MCE_INTEL=y
CONFIG_X86_MCE_AMD=y
CONFIG_X86_MCE_THRESHOLD=y
# CONFIG_X86_MCE_INJECT is not set
CONFIG_X86_THERMAL_VECTOR=y

#
# Performance monitoring
#
CONFIG_PERF_EVENTS_INTEL_UNCORE=y
CONFIG_PERF_EVENTS_INTEL_RAPL=y
CONFIG_PERF_EVENTS_INTEL_CSTATE=y
# CONFIG_PERF_EVENTS_AMD_POWER is not set
CONFIG_X86_16BIT=y
CONFIG_X86_ESPFIX64=y
CONFIG_X86_VSYSCALL_EMULATION=y
# CONFIG_I8K is not set
CONFIG_MICROCODE=y
CONFIG_MICROCODE_INTEL=y
CONFIG_MICROCODE_AMD=y
CONFIG_MICROCODE_OLD_INTERFACE=y
CONFIG_X86_MSR=y
CONFIG_X86_CPUID=y
# CONFIG_X86_5LEVEL is not set
CONFIG_ARCH_PHYS_ADDR_T_64BIT=y
CONFIG_ARCH_DMA_ADDR_T_64BIT=y
CONFIG_X86_DIRECT_GBPAGES=y
CONFIG_ARCH_HAS_MEM_ENCRYPT=y
# CONFIG_AMD_MEM_ENCRYPT is not set
CONFIG_NUMA=y
# CONFIG_AMD_NUMA is not set
# CONFIG_X86_64_ACPI_NUMA is not set
CONFIG_NUMA_EMU=y
CONFIG_NODES_SHIFT=10
CONFIG_ARCH_SPARSEMEM_ENABLE=y
CONFIG_ARCH_SPARSEMEM_DEFAULT=y
CONFIG_ARCH_SELECT_MEMORY_MODEL=y
# CONFIG_ARCH_MEMORY_PROBE is not set
CONFIG_ARCH_PROC_KCORE_TEXT=y
CONFIG_ILLEGAL_POINTER_VALUE=0xdead000000000000
CONFIG_SELECT_MEMORY_MODEL=y
CONFIG_SPARSEMEM_MANUAL=y
CONFIG_SPARSEMEM=y
CONFIG_NEED_MULTIPLE_NODES=y
CONFIG_HAVE_MEMORY_PRESENT=y
CONFIG_SPARSEMEM_EXTREME=y
CONFIG_SPARSEMEM_VMEMMAP_ENABLE=y
CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER=y
CONFIG_SPARSEMEM_VMEMMAP=y
CONFIG_HAVE_MEMBLOCK=y
CONFIG_HAVE_MEMBLOCK_NODE_MAP=y
CONFIG_HAVE_GENERIC_GUP=y
CONFIG_ARCH_DISCARD_MEMBLOCK=y
CONFIG_MEMORY_ISOLATION=y
CONFIG_HAVE_BOOTMEM_INFO_NODE=y
CONFIG_MEMORY_HOTPLUG=y
CONFIG_MEMORY_HOTPLUG_SPARSE=y
# CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE is not set
CONFIG_MEMORY_HOTREMOVE=y
CONFIG_SPLIT_PTLOCK_CPUS=4
CONFIG_ARCH_ENABLE_SPLIT_PMD_PTLOCK=y
CONFIG_MEMORY_BALLOON=y
CONFIG_BALLOON_COMPACTION=y
CONFIG_COMPACTION=y
CONFIG_MIGRATION=y
CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION=y
CONFIG_ARCH_ENABLE_THP_MIGRATION=y
CONFIG_PHYS_ADDR_T_64BIT=y
CONFIG_BOUNCE=y
CONFIG_VIRT_TO_BUS=y
CONFIG_MMU_NOTIFIER=y
# CONFIG_KSM is not set
CONFIG_DEFAULT_MMAP_MIN_ADDR=4096
CONFIG_ARCH_SUPPORTS_MEMORY_FAILURE=y
# CONFIG_MEMORY_FAILURE is not set
CONFIG_TRANSPARENT_HUGEPAGE=y
CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS=y
# CONFIG_TRANSPARENT_HUGEPAGE_MADVISE is not set
CONFIG_ARCH_WANTS_THP_SWAP=y
CONFIG_THP_SWAP=y
CONFIG_TRANSPARENT_HUGE_PAGECACHE=y
CONFIG_CLEANCACHE=y
CONFIG_FRONTSWAP=y
# CONFIG_CMA is not set
# CONFIG_ZSWAP is not set
CONFIG_ZPOOL=y
# CONFIG_ZBUD is not set
CONFIG_Z3FOLD=y
# CONFIG_ZSMALLOC is not set
CONFIG_GENERIC_EARLY_IOREMAP=y
CONFIG_DEFERRED_STRUCT_PAGE_INIT=y
CONFIG_IDLE_PAGE_TRACKING=y
CONFIG_ARCH_HAS_ZONE_DEVICE=y
CONFIG_ZONE_DEVICE=y
CONFIG_ARCH_HAS_HMM=y
# CONFIG_HMM_MIRROR is not set
# CONFIG_DEVICE_PRIVATE is not set
# CONFIG_DEVICE_PUBLIC is not set
CONFIG_ARCH_USES_HIGH_VMA_FLAGS=y
CONFIG_ARCH_HAS_PKEYS=y
# CONFIG_PERCPU_STATS is not set
# CONFIG_GUP_BENCHMARK is not set
CONFIG_X86_PMEM_LEGACY_DEVICE=y
CONFIG_X86_PMEM_LEGACY=y
CONFIG_X86_CHECK_BIOS_CORRUPTION=y
CONFIG_X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK=y
CONFIG_X86_RESERVE_LOW=64
CONFIG_MTRR=y
# CONFIG_MTRR_SANITIZER is not set
CONFIG_X86_PAT=y
CONFIG_ARCH_USES_PG_UNCACHED=y
CONFIG_ARCH_RANDOM=y
CONFIG_X86_SMAP=y
CONFIG_X86_INTEL_UMIP=y
CONFIG_X86_INTEL_MPX=y
CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS=y
CONFIG_EFI=y
# CONFIG_EFI_STUB is not set
CONFIG_SECCOMP=y
# CONFIG_HZ_100 is not set
CONFIG_HZ_250=y
# CONFIG_HZ_300 is not set
# CONFIG_HZ_1000 is not set
CONFIG_HZ=250
CONFIG_SCHED_HRTICK=y
CONFIG_KEXEC=y
# CONFIG_KEXEC_FILE is not set
CONFIG_CRASH_DUMP=y
CONFIG_PHYSICAL_START=0x1000000
CONFIG_RELOCATABLE=y
# CONFIG_RANDOMIZE_BASE is not set
CONFIG_PHYSICAL_ALIGN=0x1000000
CONFIG_HOTPLUG_CPU=y
# CONFIG_BOOTPARAM_HOTPLUG_CPU0 is not set
# CONFIG_DEBUG_HOTPLUG_CPU0 is not set
# CONFIG_COMPAT_VDSO is not set
CONFIG_LEGACY_VSYSCALL_EMULATE=y
# CONFIG_LEGACY_VSYSCALL_NONE is not set
# CONFIG_CMDLINE_BOOL is not set
CONFIG_MODIFY_LDT_SYSCALL=y
CONFIG_HAVE_LIVEPATCH=y
CONFIG_ARCH_HAS_ADD_PAGES=y
CONFIG_ARCH_ENABLE_MEMORY_HOTPLUG=y
CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE=y
CONFIG_USE_PERCPU_NUMA_NODE_ID=y

#
# Power management and ACPI options
#
# CONFIG_SUSPEND is not set
# CONFIG_HIBERNATION is not set
CONFIG_PM=y
CONFIG_PM_DEBUG=y
# CONFIG_PM_ADVANCED_DEBUG is not set
CONFIG_PM_CLK=y
# CONFIG_WQ_POWER_EFFICIENT_DEFAULT is not set
CONFIG_ACPI=y
CONFIG_ACPI_LEGACY_TABLES_LOOKUP=y
CONFIG_ARCH_MIGHT_HAVE_ACPI_PDC=y
CONFIG_ACPI_SYSTEM_POWER_STATES_SUPPORT=y
# CONFIG_ACPI_DEBUGGER is not set
CONFIG_ACPI_SPCR_TABLE=y
CONFIG_ACPI_LPIT=y
CONFIG_ACPI_PROCFS_POWER=y
CONFIG_ACPI_REV_OVERRIDE_POSSIBLE=y
# CONFIG_ACPI_EC_DEBUGFS is not set
CONFIG_ACPI_AC=y
CONFIG_ACPI_BATTERY=y
CONFIG_ACPI_BUTTON=y
CONFIG_ACPI_FAN=y
CONFIG_ACPI_DOCK=y
CONFIG_ACPI_CPU_FREQ_PSS=y
CONFIG_ACPI_PROCESSOR_CSTATE=y
CONFIG_ACPI_PROCESSOR_IDLE=y
CONFIG_ACPI_CPPC_LIB=y
CONFIG_ACPI_PROCESSOR=y
CONFIG_ACPI_HOTPLUG_CPU=y
CONFIG_ACPI_PROCESSOR_AGGREGATOR=y
CONFIG_ACPI_THERMAL=y
# CONFIG_ACPI_NUMA is not set
CONFIG_ARCH_HAS_ACPI_TABLE_UPGRADE=y
CONFIG_ACPI_TABLE_UPGRADE=y
# CONFIG_ACPI_DEBUG is not set
# CONFIG_ACPI_PCI_SLOT is not set
CONFIG_ACPI_CONTAINER=y
# CONFIG_ACPI_HOTPLUG_MEMORY is not set
CONFIG_ACPI_HOTPLUG_IOAPIC=y
# CONFIG_ACPI_SBS is not set
# CONFIG_ACPI_HED is not set
# CONFIG_ACPI_CUSTOM_METHOD is not set
# CONFIG_ACPI_BGRT is not set
# CONFIG_ACPI_REDUCED_HARDWARE_ONLY is not set
CONFIG_ACPI_NFIT=y
CONFIG_HAVE_ACPI_APEI=y
CONFIG_HAVE_ACPI_APEI_NMI=y
# CONFIG_ACPI_APEI is not set
# CONFIG_DPTF_POWER is not set
# CONFIG_ACPI_EXTLOG is not set
# CONFIG_PMIC_OPREGION is not set
CONFIG_ACPI_CONFIGFS=y
CONFIG_X86_PM_TIMER=y
# CONFIG_SFI is not set

#
# CPU Frequency scaling
#
CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_GOV_ATTR_SET=y
CONFIG_CPU_FREQ_GOV_COMMON=y
# CONFIG_CPU_FREQ_STAT is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE is not set
CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE=y
# CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDUTIL is not set
CONFIG_CPU_FREQ_GOV_PERFORMANCE=y
# CONFIG_CPU_FREQ_GOV_POWERSAVE is not set
CONFIG_CPU_FREQ_GOV_USERSPACE=y
CONFIG_CPU_FREQ_GOV_ONDEMAND=y
# CONFIG_CPU_FREQ_GOV_CONSERVATIVE is not set
# CONFIG_CPU_FREQ_GOV_SCHEDUTIL is not set

#
# CPU frequency scaling drivers
#
CONFIG_X86_INTEL_PSTATE=y
# CONFIG_X86_PCC_CPUFREQ is not set
CONFIG_X86_ACPI_CPUFREQ=y
CONFIG_X86_ACPI_CPUFREQ_CPB=y
CONFIG_X86_POWERNOW_K8=y
# CONFIG_X86_AMD_FREQ_SENSITIVITY is not set
# CONFIG_X86_SPEEDSTEP_CENTRINO is not set
# CONFIG_X86_P4_CLOCKMOD is not set

#
# shared options
#

#
# CPU Idle
#
CONFIG_CPU_IDLE=y
CONFIG_CPU_IDLE_GOV_LADDER=y
CONFIG_CPU_IDLE_GOV_MENU=y
# CONFIG_INTEL_IDLE is not set

#
# Bus options (PCI etc.)
#
CONFIG_PCI=y
CONFIG_PCI_DIRECT=y
CONFIG_PCI_MMCONFIG=y
CONFIG_PCI_DOMAINS=y
CONFIG_MMCONF_FAM10H=y
# CONFIG_PCI_CNB20LE_QUIRK is not set
CONFIG_PCIEPORTBUS=y
# CONFIG_HOTPLUG_PCI_PCIE is not set
CONFIG_PCIEAER=y
# CONFIG_PCIE_ECRC is not set
# CONFIG_PCIEAER_INJECT is not set
CONFIG_PCIEASPM=y
# CONFIG_PCIEASPM_DEBUG is not set
CONFIG_PCIEASPM_DEFAULT=y
# CONFIG_PCIEASPM_POWERSAVE is not set
# CONFIG_PCIEASPM_POWER_SUPERSAVE is not set
# CONFIG_PCIEASPM_PERFORMANCE is not set
CONFIG_PCIE_PME=y
# CONFIG_PCIE_DPC is not set
# CONFIG_PCIE_PTM is not set
CONFIG_PCI_BUS_ADDR_T_64BIT=y
CONFIG_PCI_MSI=y
CONFIG_PCI_MSI_IRQ_DOMAIN=y
CONFIG_PCI_QUIRKS=y
# CONFIG_PCI_DEBUG is not set
# CONFIG_PCI_REALLOC_ENABLE_AUTO is not set
# CONFIG_PCI_STUB is not set
CONFIG_PCI_ATS=y
CONFIG_PCI_LOCKLESS_CONFIG=y
CONFIG_PCI_IOV=y
CONFIG_PCI_PRI=y
CONFIG_PCI_PASID=y
CONFIG_PCI_LABEL=y
CONFIG_HOTPLUG_PCI=y
# CONFIG_HOTPLUG_PCI_ACPI is not set
# CONFIG_HOTPLUG_PCI_CPCI is not set
# CONFIG_HOTPLUG_PCI_SHPC is not set

#
# Cadence PCIe controllers support
#

#
# DesignWare PCI Core Support
#
# CONFIG_PCIE_DW_PLAT is not set

#
# PCI host controller drivers
#
# CONFIG_VMD is not set

#
# PCI Endpoint
#
# CONFIG_PCI_ENDPOINT is not set

#
# PCI switch controller drivers
#
# CONFIG_PCI_SW_SWITCHTEC is not set
# CONFIG_ISA_BUS is not set
CONFIG_ISA_DMA_API=y
CONFIG_AMD_NB=y
# CONFIG_PCCARD is not set
# CONFIG_RAPIDIO is not set
# CONFIG_X86_SYSFB is not set

#
# Executable file formats / Emulations
#
CONFIG_BINFMT_ELF=y
CONFIG_COMPAT_BINFMT_ELF=y
CONFIG_ELFCORE=y
CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS=y
CONFIG_BINFMT_SCRIPT=y
CONFIG_BINFMT_MISC=y
CONFIG_COREDUMP=y
CONFIG_IA32_EMULATION=y
# CONFIG_IA32_AOUT is not set
# CONFIG_X86_X32 is not set
CONFIG_COMPAT_32=y
CONFIG_COMPAT=y
CONFIG_COMPAT_FOR_U64_ALIGNMENT=y
CONFIG_SYSVIPC_COMPAT=y
CONFIG_X86_DEV_DMA_OPS=y
CONFIG_NET=y

#
# Networking options
#
CONFIG_PACKET=y
# CONFIG_PACKET_DIAG is not set
CONFIG_UNIX=y
# CONFIG_UNIX_DIAG is not set
# CONFIG_TLS is not set
# CONFIG_XFRM_USER is not set
# CONFIG_NET_KEY is not set
CONFIG_INET=y
CONFIG_IP_MULTICAST=y
CONFIG_IP_ADVANCED_ROUTER=y
# CONFIG_IP_FIB_TRIE_STATS is not set
CONFIG_IP_MULTIPLE_TABLES=y
CONFIG_IP_ROUTE_MULTIPATH=y
CONFIG_IP_ROUTE_VERBOSE=y
CONFIG_IP_PNP=y
CONFIG_IP_PNP_DHCP=y
CONFIG_IP_PNP_BOOTP=y
CONFIG_IP_PNP_RARP=y
# CONFIG_NET_IPIP is not set
# CONFIG_NET_IPGRE_DEMUX is not set
CONFIG_IP_MROUTE_COMMON=y
CONFIG_IP_MROUTE=y
# CONFIG_IP_MROUTE_MULTIPLE_TABLES is not set
CONFIG_IP_PIMSM_V1=y
CONFIG_IP_PIMSM_V2=y
CONFIG_SYN_COOKIES=y
# CONFIG_NET_FOU is not set
# CONFIG_INET_AH is not set
# CONFIG_INET_ESP is not set
# CONFIG_INET_IPCOMP is not set
# CONFIG_INET_XFRM_MODE_TRANSPORT is not set
# CONFIG_INET_XFRM_MODE_TUNNEL is not set
# CONFIG_INET_XFRM_MODE_BEET is not set
# CONFIG_INET_DIAG is not set
CONFIG_TCP_CONG_ADVANCED=y
# CONFIG_TCP_CONG_BIC is not set
CONFIG_TCP_CONG_CUBIC=y
# CONFIG_TCP_CONG_WESTWOOD is not set
# CONFIG_TCP_CONG_HTCP is not set
# CONFIG_TCP_CONG_HSTCP is not set
# CONFIG_TCP_CONG_HYBLA is not set
# CONFIG_TCP_CONG_VEGAS is not set
# CONFIG_TCP_CONG_NV is not set
# CONFIG_TCP_CONG_SCALABLE is not set
# CONFIG_TCP_CONG_LP is not set
# CONFIG_TCP_CONG_VENO is not set
# CONFIG_TCP_CONG_YEAH is not set
# CONFIG_TCP_CONG_ILLINOIS is not set
# CONFIG_TCP_CONG_DCTCP is not set
# CONFIG_TCP_CONG_CDG is not set
# CONFIG_TCP_CONG_BBR is not set
CONFIG_DEFAULT_CUBIC=y
# CONFIG_DEFAULT_RENO is not set
CONFIG_DEFAULT_TCP_CONG="cubic"
CONFIG_TCP_MD5SIG=y
# CONFIG_IPV6 is not set
# CONFIG_NETLABEL is not set
CONFIG_NETWORK_SECMARK=y
# CONFIG_NETWORK_PHY_TIMESTAMPING is not set
# CONFIG_NETFILTER is not set
# CONFIG_IP_DCCP is not set
CONFIG_IP_SCTP=y
# CONFIG_SCTP_DBG_OBJCNT is not set
CONFIG_SCTP_DEFAULT_COOKIE_HMAC_MD5=y
# CONFIG_SCTP_DEFAULT_COOKIE_HMAC_SHA1 is not set
# CONFIG_SCTP_DEFAULT_COOKIE_HMAC_NONE is not set
CONFIG_SCTP_COOKIE_HMAC_MD5=y
CONFIG_SCTP_COOKIE_HMAC_SHA1=y
# CONFIG_RDS is not set
# CONFIG_TIPC is not set
# CONFIG_ATM is not set
# CONFIG_L2TP is not set
# CONFIG_BRIDGE is not set
CONFIG_HAVE_NET_DSA=y
# CONFIG_NET_DSA is not set
# CONFIG_VLAN_8021Q is not set
# CONFIG_DECNET is not set
# CONFIG_LLC2 is not set
# CONFIG_ATALK is not set
# CONFIG_X25 is not set
# CONFIG_LAPB is not set
# CONFIG_PHONET is not set
# CONFIG_IEEE802154 is not set
# CONFIG_NET_SCHED is not set
# CONFIG_DCB is not set
CONFIG_DNS_RESOLVER=y
# CONFIG_BATMAN_ADV is not set
# CONFIG_OPENVSWITCH is not set
# CONFIG_VSOCKETS is not set
# CONFIG_NETLINK_DIAG is not set
# CONFIG_MPLS is not set
# CONFIG_NET_NSH is not set
# CONFIG_HSR is not set
# CONFIG_NET_SWITCHDEV is not set
# CONFIG_NET_L3_MASTER_DEV is not set
# CONFIG_NET_NCSI is not set
CONFIG_RPS=y
CONFIG_RFS_ACCEL=y
CONFIG_XPS=y
# CONFIG_CGROUP_NET_PRIO is not set
# CONFIG_CGROUP_NET_CLASSID is not set
CONFIG_NET_RX_BUSY_POLL=y
CONFIG_BQL=y
CONFIG_NET_FLOW_LIMIT=y

#
# Network testing
#
# CONFIG_NET_PKTGEN is not set
# CONFIG_NET_DROP_MONITOR is not set
# CONFIG_HAMRADIO is not set
# CONFIG_CAN is not set
# CONFIG_BT is not set
# CONFIG_AF_RXRPC is not set
# CONFIG_AF_KCM is not set
CONFIG_FIB_RULES=y
# CONFIG_WIRELESS is not set
# CONFIG_WIMAX is not set
# CONFIG_RFKILL is not set
# CONFIG_NET_9P is not set
# CONFIG_CAIF is not set
CONFIG_CEPH_LIB=y
# CONFIG_CEPH_LIB_PRETTYDEBUG is not set
# CONFIG_CEPH_LIB_USE_DNS_RESOLVER is not set
# CONFIG_NFC is not set
# CONFIG_PSAMPLE is not set
# CONFIG_NET_IFE is not set
# CONFIG_LWTUNNEL is not set
# CONFIG_NET_DEVLINK is not set
CONFIG_MAY_USE_DEVLINK=y
CONFIG_HAVE_EBPF_JIT=y

#
# Device Drivers
#

#
# Generic Driver Options
#
CONFIG_UEVENT_HELPER=y
CONFIG_UEVENT_HELPER_PATH="/sbin/hotplug"
CONFIG_DEVTMPFS=y
# CONFIG_DEVTMPFS_MOUNT is not set
CONFIG_STANDALONE=y
CONFIG_PREVENT_FIRMWARE_BUILD=y
CONFIG_FW_LOADER=y
CONFIG_EXTRA_FIRMWARE=""
# CONFIG_FW_LOADER_USER_HELPER_FALLBACK is not set
CONFIG_ALLOW_DEV_COREDUMP=y
# CONFIG_DEBUG_DRIVER is not set
CONFIG_DEBUG_DEVRES=y
# CONFIG_DEBUG_TEST_DRIVER_REMOVE is not set
CONFIG_GENERIC_CPU_AUTOPROBE=y
CONFIG_GENERIC_CPU_VULNERABILITIES=y
CONFIG_REGMAP=y
CONFIG_REGMAP_I2C=y
CONFIG_DMA_SHARED_BUFFER=y
# CONFIG_DMA_FENCE_TRACE is not set

#
# Bus devices
#
CONFIG_CONNECTOR=y
CONFIG_PROC_EVENTS=y
# CONFIG_MTD is not set
# CONFIG_OF is not set
CONFIG_ARCH_MIGHT_HAVE_PC_PARPORT=y
# CONFIG_PARPORT is not set
CONFIG_PNP=y
CONFIG_PNP_DEBUG_MESSAGES=y

#
# Protocols
#
CONFIG_PNPACPI=y
CONFIG_BLK_DEV=y
# CONFIG_BLK_DEV_NULL_BLK is not set
# CONFIG_BLK_DEV_FD is not set
CONFIG_CDROM=y
# CONFIG_BLK_DEV_PCIESSD_MTIP32XX is not set
# CONFIG_BLK_DEV_DAC960 is not set
# CONFIG_BLK_DEV_UMEM is not set
CONFIG_BLK_DEV_LOOP=y
CONFIG_BLK_DEV_LOOP_MIN_COUNT=8
CONFIG_BLK_DEV_CRYPTOLOOP=y
# CONFIG_BLK_DEV_DRBD is not set
# CONFIG_BLK_DEV_NBD is not set
# CONFIG_BLK_DEV_SKD is not set
# CONFIG_BLK_DEV_SX8 is not set
CONFIG_BLK_DEV_RAM=y
CONFIG_BLK_DEV_RAM_COUNT=4
CONFIG_BLK_DEV_RAM_SIZE=8192000
# CONFIG_CDROM_PKTCDVD is not set
# CONFIG_ATA_OVER_ETH is not set
CONFIG_VIRTIO_BLK=y
CONFIG_VIRTIO_BLK_SCSI=y
# CONFIG_BLK_DEV_RBD is not set
# CONFIG_BLK_DEV_RSXX is not set

#
# NVME Support
#
CONFIG_NVME_CORE=y
# CONFIG_BLK_DEV_NVME is not set
CONFIG_NVME_MULTIPATH=y
CONFIG_NVME_FABRICS=y
# CONFIG_NVME_FC is not set
CONFIG_NVME_TARGET=y
CONFIG_NVME_TARGET_LOOP=y
# CONFIG_NVME_TARGET_FC is not set

#
# Misc devices
#
# CONFIG_AD525X_DPOT is not set
# CONFIG_DUMMY_IRQ is not set
# CONFIG_IBM_ASM is not set
# CONFIG_PHANTOM is not set
# CONFIG_SGI_IOC4 is not set
# CONFIG_TIFM_CORE is not set
# CONFIG_ICS932S401 is not set
# CONFIG_ENCLOSURE_SERVICES is not set
# CONFIG_HP_ILO is not set
# CONFIG_APDS9802ALS is not set
# CONFIG_ISL29003 is not set
# CONFIG_ISL29020 is not set
# CONFIG_SENSORS_TSL2550 is not set
# CONFIG_SENSORS_BH1770 is not set
# CONFIG_SENSORS_APDS990X is not set
# CONFIG_HMC6352 is not set
# CONFIG_DS1682 is not set
# CONFIG_USB_SWITCH_FSA9480 is not set
# CONFIG_SRAM is not set
# CONFIG_PCI_ENDPOINT_TEST is not set
# CONFIG_C2PORT is not set

#
# EEPROM support
#
# CONFIG_EEPROM_AT24 is not set
# CONFIG_EEPROM_LEGACY is not set
# CONFIG_EEPROM_MAX6875 is not set
# CONFIG_EEPROM_93CX6 is not set
# CONFIG_EEPROM_IDT_89HPESX is not set
# CONFIG_CB710_CORE is not set

#
# Texas Instruments shared transport line discipline
#
# CONFIG_SENSORS_LIS3_I2C is not set
# CONFIG_ALTERA_STAPL is not set
# CONFIG_INTEL_MEI is not set
# CONFIG_INTEL_MEI_ME is not set
# CONFIG_INTEL_MEI_TXE is not set
# CONFIG_VMWARE_VMCI is not set

#
# Intel MIC & related support
#

#
# Intel MIC Bus Driver
#
# CONFIG_INTEL_MIC_BUS is not set

#
# SCIF Bus Driver
#
# CONFIG_SCIF_BUS is not set

#
# VOP Bus Driver
#
# CONFIG_VOP_BUS is not set

#
# Intel MIC Host Driver
#

#
# Intel MIC Card Driver
#

#
# SCIF Driver
#

#
# Intel MIC Coprocessor State Management (COSM) Drivers
#

#
# VOP Driver
#
# CONFIG_GENWQE is not set
# CONFIG_ECHO is not set
# CONFIG_MISC_RTSX_PCI is not set
CONFIG_HAVE_IDE=y
# CONFIG_IDE is not set

#
# SCSI device support
#
CONFIG_SCSI_MOD=y
# CONFIG_RAID_ATTRS is not set
CONFIG_SCSI=y
CONFIG_SCSI_DMA=y
CONFIG_SCSI_MQ_DEFAULT=y
CONFIG_SCSI_PROC_FS=y

#
# SCSI support type (disk, tape, CD-ROM)
#
CONFIG_BLK_DEV_SD=y
# CONFIG_CHR_DEV_ST is not set
# CONFIG_CHR_DEV_OSST is not set
CONFIG_BLK_DEV_SR=y
CONFIG_BLK_DEV_SR_VENDOR=y
CONFIG_CHR_DEV_SG=y
# CONFIG_CHR_DEV_SCH is not set
CONFIG_SCSI_CONSTANTS=y
# CONFIG_SCSI_LOGGING is not set
# CONFIG_SCSI_SCAN_ASYNC is not set

#
# SCSI Transports
#
CONFIG_SCSI_SPI_ATTRS=y
# CONFIG_SCSI_FC_ATTRS is not set
CONFIG_SCSI_ISCSI_ATTRS=y
# CONFIG_SCSI_SAS_ATTRS is not set
# CONFIG_SCSI_SAS_LIBSAS is not set
CONFIG_SCSI_SRP_ATTRS=y
CONFIG_SCSI_LOWLEVEL=y
CONFIG_ISCSI_TCP=y
CONFIG_ISCSI_BOOT_SYSFS=y
# CONFIG_SCSI_CXGB3_ISCSI is not set
# CONFIG_SCSI_CXGB4_ISCSI is not set
# CONFIG_SCSI_BNX2_ISCSI is not set
# CONFIG_BE2ISCSI is not set
# CONFIG_BLK_DEV_3W_XXXX_RAID is not set
# CONFIG_SCSI_HPSA is not set
# CONFIG_SCSI_3W_9XXX is not set
# CONFIG_SCSI_3W_SAS is not set
# CONFIG_SCSI_ACARD is not set
# CONFIG_SCSI_AACRAID is not set
# CONFIG_SCSI_AIC7XXX is not set
# CONFIG_SCSI_AIC79XX is not set
# CONFIG_SCSI_AIC94XX is not set
# CONFIG_SCSI_MVSAS is not set
# CONFIG_SCSI_MVUMI is not set
# CONFIG_SCSI_DPT_I2O is not set
# CONFIG_SCSI_ADVANSYS is not set
# CONFIG_SCSI_ARCMSR is not set
# CONFIG_SCSI_ESAS2R is not set
CONFIG_MEGARAID_NEWGEN=y
CONFIG_MEGARAID_MM=y
CONFIG_MEGARAID_MAILBOX=y
# CONFIG_MEGARAID_LEGACY is not set
# CONFIG_MEGARAID_SAS is not set
# CONFIG_SCSI_MPT3SAS is not set
# CONFIG_SCSI_MPT2SAS is not set
# CONFIG_SCSI_SMARTPQI is not set
# CONFIG_SCSI_UFSHCD is not set
# CONFIG_SCSI_HPTIOP is not set
# CONFIG_SCSI_BUSLOGIC is not set
# CONFIG_VMWARE_PVSCSI is not set
# CONFIG_SCSI_SNIC is not set
# CONFIG_SCSI_DMX3191D is not set
# CONFIG_SCSI_GDTH is not set
# CONFIG_SCSI_ISCI is not set
# CONFIG_SCSI_IPS is not set
# CONFIG_SCSI_INITIO is not set
# CONFIG_SCSI_INIA100 is not set
# CONFIG_SCSI_STEX is not set
# CONFIG_SCSI_SYM53C8XX_2 is not set
# CONFIG_SCSI_IPR is not set
# CONFIG_SCSI_QLOGIC_1280 is not set
# CONFIG_SCSI_QLA_ISCSI is not set
# CONFIG_SCSI_DC395x is not set
# CONFIG_SCSI_AM53C974 is not set
# CONFIG_SCSI_WD719X is not set
CONFIG_SCSI_DEBUG=y
# CONFIG_SCSI_PMCRAID is not set
# CONFIG_SCSI_PM8001 is not set
CONFIG_SCSI_VIRTIO=y
# CONFIG_SCSI_DH is not set
# CONFIG_SCSI_OSD_INITIATOR is not set
CONFIG_ATA=y
CONFIG_ATA_VERBOSE_ERROR=y
CONFIG_ATA_ACPI=y
# CONFIG_SATA_ZPODD is not set
CONFIG_SATA_PMP=y

#
# Controllers with non-SFF native interface
#
CONFIG_SATA_AHCI=y
CONFIG_SATA_MOBILE_LPM_POLICY=0
CONFIG_SATA_AHCI_PLATFORM=y
# CONFIG_SATA_INIC162X is not set
# CONFIG_SATA_ACARD_AHCI is not set
# CONFIG_SATA_SIL24 is not set
CONFIG_ATA_SFF=y

#
# SFF controllers with custom DMA interface
#
# CONFIG_PDC_ADMA is not set
# CONFIG_SATA_QSTOR is not set
# CONFIG_SATA_SX4 is not set
CONFIG_ATA_BMDMA=y

#
# SATA SFF controllers with BMDMA
#
CONFIG_ATA_PIIX=y
# CONFIG_SATA_DWC is not set
# CONFIG_SATA_MV is not set
# CONFIG_SATA_NV is not set
# CONFIG_SATA_PROMISE is not set
# CONFIG_SATA_SIL is not set
# CONFIG_SATA_SIS is not set
# CONFIG_SATA_SVW is not set
# CONFIG_SATA_ULI is not set
# CONFIG_SATA_VIA is not set
# CONFIG_SATA_VITESSE is not set

#
# PATA SFF controllers with BMDMA
#
# CONFIG_PATA_ALI is not set
CONFIG_PATA_AMD=y
# CONFIG_PATA_ARTOP is not set
# CONFIG_PATA_ATIIXP is not set
# CONFIG_PATA_ATP867X is not set
# CONFIG_PATA_CMD64X is not set
# CONFIG_PATA_CYPRESS is not set
# CONFIG_PATA_EFAR is not set
# CONFIG_PATA_HPT366 is not set
# CONFIG_PATA_HPT37X is not set
# CONFIG_PATA_HPT3X2N is not set
# CONFIG_PATA_HPT3X3 is not set
# CONFIG_PATA_IT8213 is not set
# CONFIG_PATA_IT821X is not set
# CONFIG_PATA_JMICRON is not set
# CONFIG_PATA_MARVELL is not set
# CONFIG_PATA_NETCELL is not set
# CONFIG_PATA_NINJA32 is not set
# CONFIG_PATA_NS87415 is not set
CONFIG_PATA_OLDPIIX=y
# CONFIG_PATA_OPTIDMA is not set
# CONFIG_PATA_PDC2027X is not set
# CONFIG_PATA_PDC_OLD is not set
# CONFIG_PATA_RADISYS is not set
# CONFIG_PATA_RDC is not set
CONFIG_PATA_SCH=y
# CONFIG_PATA_SERVERWORKS is not set
# CONFIG_PATA_SIL680 is not set
# CONFIG_PATA_SIS is not set
# CONFIG_PATA_TOSHIBA is not set
# CONFIG_PATA_TRIFLEX is not set
# CONFIG_PATA_VIA is not set
# CONFIG_PATA_WINBOND is not set

#
# PIO-only SFF controllers
#
# CONFIG_PATA_CMD640_PCI is not set
# CONFIG_PATA_MPIIX is not set
# CONFIG_PATA_NS87410 is not set
# CONFIG_PATA_OPTI is not set
# CONFIG_PATA_PLATFORM is not set
# CONFIG_PATA_RZ1000 is not set

#
# Generic fallback / legacy drivers
#
# CONFIG_PATA_ACPI is not set
# CONFIG_ATA_GENERIC is not set
# CONFIG_PATA_LEGACY is not set
CONFIG_MD=y
CONFIG_BLK_DEV_MD=y
CONFIG_MD_AUTODETECT=y
CONFIG_MD_LINEAR=y
CONFIG_MD_RAID0=y
CONFIG_MD_RAID1=y
CONFIG_MD_RAID10=y
CONFIG_MD_RAID456=y
# CONFIG_MD_MULTIPATH is not set
# CONFIG_MD_FAULTY is not set
# CONFIG_MD_CLUSTER is not set
CONFIG_BCACHE=y
# CONFIG_BCACHE_DEBUG is not set
# CONFIG_BCACHE_CLOSURES_DEBUG is not set
CONFIG_BLK_DEV_DM_BUILTIN=y
CONFIG_BLK_DEV_DM=y
CONFIG_DM_MQ_DEFAULT=y
# CONFIG_DM_DEBUG is not set
CONFIG_DM_BUFIO=y
CONFIG_DM_DEBUG_BLOCK_MANAGER_LOCKING=y
# CONFIG_DM_DEBUG_BLOCK_STACK_TRACING is not set
CONFIG_DM_BIO_PRISON=y
CONFIG_DM_PERSISTENT_DATA=y
CONFIG_DM_UNSTRIPED=y
CONFIG_DM_CRYPT=y
CONFIG_DM_SNAPSHOT=y
CONFIG_DM_THIN_PROVISIONING=y
CONFIG_DM_CACHE=y
CONFIG_DM_CACHE_SMQ=y
# CONFIG_DM_ERA is not set
CONFIG_DM_MIRROR=y
# CONFIG_DM_LOG_USERSPACE is not set
CONFIG_DM_RAID=y
CONFIG_DM_ZERO=y
# CONFIG_DM_MULTIPATH is not set
CONFIG_DM_DELAY=y
# CONFIG_DM_UEVENT is not set
CONFIG_DM_FLAKEY=y
CONFIG_DM_VERITY=y
# CONFIG_DM_VERITY_FEC is not set
CONFIG_DM_SWITCH=y
CONFIG_DM_LOG_WRITES=y
CONFIG_DM_INTEGRITY=y
CONFIG_DM_ZONED=y
# CONFIG_TARGET_CORE is not set
# CONFIG_FUSION is not set

#
# IEEE 1394 (FireWire) support
#
# CONFIG_FIREWIRE is not set
# CONFIG_FIREWIRE_NOSY is not set
# CONFIG_MACINTOSH_DRIVERS is not set
CONFIG_NETDEVICES=y
CONFIG_MII=y
CONFIG_NET_CORE=y
# CONFIG_BONDING is not set
# CONFIG_DUMMY is not set
# CONFIG_EQUALIZER is not set
# CONFIG_NET_FC is not set
# CONFIG_NET_TEAM is not set
# CONFIG_MACVLAN is not set
# CONFIG_VXLAN is not set
# CONFIG_MACSEC is not set
# CONFIG_NETCONSOLE is not set
# CONFIG_TUN is not set
# CONFIG_TUN_VNET_CROSS_LE is not set
# CONFIG_VETH is not set
CONFIG_VIRTIO_NET=y
# CONFIG_NLMON is not set
# CONFIG_ARCNET is not set

#
# CAIF transport drivers
#

#
# Distributed Switch Architecture drivers
#
CONFIG_ETHERNET=y
# CONFIG_NET_VENDOR_3COM is not set
# CONFIG_NET_VENDOR_ADAPTEC is not set
CONFIG_NET_VENDOR_AGERE=y
# CONFIG_ET131X is not set
# CONFIG_NET_VENDOR_ALACRITECH is not set
# CONFIG_NET_VENDOR_ALTEON is not set
# CONFIG_ALTERA_TSE is not set
# CONFIG_NET_VENDOR_AMAZON is not set
# CONFIG_NET_VENDOR_AMD is not set
# CONFIG_NET_VENDOR_AQUANTIA is not set
CONFIG_NET_VENDOR_ARC=y
# CONFIG_NET_VENDOR_ATHEROS is not set
# CONFIG_NET_VENDOR_AURORA is not set
CONFIG_NET_CADENCE=y
# CONFIG_MACB is not set
# CONFIG_NET_VENDOR_BROADCOM is not set
# CONFIG_NET_VENDOR_BROCADE is not set
CONFIG_NET_VENDOR_CAVIUM=y
# CONFIG_THUNDER_NIC_PF is not set
# CONFIG_THUNDER_NIC_VF is not set
# CONFIG_THUNDER_NIC_BGX is not set
# CONFIG_THUNDER_NIC_RGX is not set
# CONFIG_CAVIUM_PTP is not set
# CONFIG_LIQUIDIO is not set
# CONFIG_LIQUIDIO_VF is not set
# CONFIG_NET_VENDOR_CHELSIO is not set
# CONFIG_NET_VENDOR_CISCO is not set
# CONFIG_NET_VENDOR_CORTINA is not set
# CONFIG_CX_ECAT is not set
# CONFIG_DNET is not set
# CONFIG_NET_VENDOR_DEC is not set
# CONFIG_NET_VENDOR_DLINK is not set
# CONFIG_NET_VENDOR_EMULEX is not set
# CONFIG_NET_VENDOR_EZCHIP is not set
# CONFIG_NET_VENDOR_EXAR is not set
# CONFIG_NET_VENDOR_HP is not set
# CONFIG_NET_VENDOR_HUAWEI is not set
# CONFIG_NET_VENDOR_INTEL is not set
# CONFIG_JME is not set
# CONFIG_NET_VENDOR_MARVELL is not set
# CONFIG_NET_VENDOR_MELLANOX is not set
# CONFIG_NET_VENDOR_MICREL is not set
# CONFIG_NET_VENDOR_MYRI is not set
# CONFIG_FEALNX is not set
# CONFIG_NET_VENDOR_NATSEMI is not set
# CONFIG_NET_VENDOR_NETRONOME is not set
CONFIG_NET_VENDOR_NI=y
# CONFIG_NET_VENDOR_NVIDIA is not set
# CONFIG_NET_VENDOR_OKI is not set
# CONFIG_ETHOC is not set
# CONFIG_NET_PACKET_ENGINE is not set
# CONFIG_NET_VENDOR_QLOGIC is not set
# CONFIG_NET_VENDOR_QUALCOMM is not set
CONFIG_NET_VENDOR_REALTEK=y
CONFIG_8139CP=y
CONFIG_8139TOO=y
CONFIG_8139TOO_PIO=y
# CONFIG_8139TOO_TUNE_TWISTER is not set
# CONFIG_8139TOO_8129 is not set
# CONFIG_8139_OLD_RX_RESET is not set
CONFIG_R8169=y
# CONFIG_NET_VENDOR_RENESAS is not set
# CONFIG_NET_VENDOR_RDC is not set
CONFIG_NET_VENDOR_ROCKER=y
CONFIG_NET_VENDOR_SAMSUNG=y
# CONFIG_SXGBE_ETH is not set
# CONFIG_NET_VENDOR_SEEQ is not set
# CONFIG_NET_VENDOR_SILAN is not set
# CONFIG_NET_VENDOR_SIS is not set
# CONFIG_NET_VENDOR_SOLARFLARE is not set
# CONFIG_NET_VENDOR_SMSC is not set
# CONFIG_NET_VENDOR_SOCIONEXT is not set
# CONFIG_NET_VENDOR_STMICRO is not set
# CONFIG_NET_VENDOR_SUN is not set
# CONFIG_NET_VENDOR_TEHUTI is not set
# CONFIG_NET_VENDOR_TI is not set
# CONFIG_NET_VENDOR_VIA is not set
CONFIG_NET_VENDOR_WIZNET=y
# CONFIG_WIZNET_W5100 is not set
# CONFIG_WIZNET_W5300 is not set
# CONFIG_NET_VENDOR_SYNOPSYS is not set
# CONFIG_FDDI is not set
# CONFIG_HIPPI is not set
# CONFIG_NET_SB1000 is not set
CONFIG_MDIO_DEVICE=y
CONFIG_MDIO_BUS=y
# CONFIG_MDIO_BITBANG is not set
# CONFIG_MDIO_THUNDER is not set
CONFIG_PHYLIB=y
# CONFIG_LED_TRIGGER_PHY is not set

#
# MII PHY device drivers
#
# CONFIG_AMD_PHY is not set
# CONFIG_AQUANTIA_PHY is not set
# CONFIG_AT803X_PHY is not set
# CONFIG_BCM7XXX_PHY is not set
# CONFIG_BCM87XX_PHY is not set
# CONFIG_BROADCOM_PHY is not set
# CONFIG_CICADA_PHY is not set
# CONFIG_CORTINA_PHY is not set
# CONFIG_DAVICOM_PHY is not set
# CONFIG_DP83822_PHY is not set
# CONFIG_DP83848_PHY is not set
# CONFIG_DP83867_PHY is not set
# CONFIG_FIXED_PHY is not set
# CONFIG_ICPLUS_PHY is not set
# CONFIG_INTEL_XWAY_PHY is not set
# CONFIG_LSI_ET1011C_PHY is not set
# CONFIG_LXT_PHY is not set
# CONFIG_MARVELL_PHY is not set
# CONFIG_MARVELL_10G_PHY is not set
# CONFIG_MICREL_PHY is not set
# CONFIG_MICROCHIP_PHY is not set
# CONFIG_MICROSEMI_PHY is not set
# CONFIG_NATIONAL_PHY is not set
# CONFIG_QSEMI_PHY is not set
# CONFIG_REALTEK_PHY is not set
# CONFIG_RENESAS_PHY is not set
# CONFIG_ROCKCHIP_PHY is not set
# CONFIG_SMSC_PHY is not set
# CONFIG_STE10XP is not set
# CONFIG_TERANETICS_PHY is not set
# CONFIG_VITESSE_PHY is not set
# CONFIG_XILINX_GMII2RGMII is not set
# CONFIG_PPP is not set
# CONFIG_SLIP is not set

#
# Host-side USB support is needed for USB Network Adapter support
#
# CONFIG_WLAN is not set

#
# Enable WiMAX (Networking options) to see the WiMAX drivers
#
# CONFIG_WAN is not set
# CONFIG_VMXNET3 is not set
# CONFIG_FUJITSU_ES is not set
# CONFIG_NETDEVSIM is not set
# CONFIG_ISDN is not set
# CONFIG_NVM is not set

#
# Input device support
#
CONFIG_INPUT=y
# CONFIG_INPUT_LEDS is not set
CONFIG_INPUT_FF_MEMLESS=y
CONFIG_INPUT_POLLDEV=y
CONFIG_INPUT_SPARSEKMAP=y
# CONFIG_INPUT_MATRIXKMAP is not set

#
# Userland interfaces
#
CONFIG_INPUT_MOUSEDEV=y
# CONFIG_INPUT_MOUSEDEV_PSAUX is not set
CONFIG_INPUT_MOUSEDEV_SCREEN_X=1024
CONFIG_INPUT_MOUSEDEV_SCREEN_Y=768
# CONFIG_INPUT_JOYDEV is not set
CONFIG_INPUT_EVDEV=y
# CONFIG_INPUT_EVBUG is not set

#
# Input Device Drivers
#
CONFIG_INPUT_KEYBOARD=y
# CONFIG_KEYBOARD_ADP5588 is not set
# CONFIG_KEYBOARD_ADP5589 is not set
CONFIG_KEYBOARD_ATKBD=y
# CONFIG_KEYBOARD_QT1070 is not set
# CONFIG_KEYBOARD_QT2160 is not set
# CONFIG_KEYBOARD_DLINK_DIR685 is not set
# CONFIG_KEYBOARD_LKKBD is not set
# CONFIG_KEYBOARD_TCA6416 is not set
# CONFIG_KEYBOARD_TCA8418 is not set
# CONFIG_KEYBOARD_LM8323 is not set
# CONFIG_KEYBOARD_LM8333 is not set
# CONFIG_KEYBOARD_MAX7359 is not set
# CONFIG_KEYBOARD_MCS is not set
# CONFIG_KEYBOARD_MPR121 is not set
# CONFIG_KEYBOARD_NEWTON is not set
# CONFIG_KEYBOARD_OPENCORES is not set
# CONFIG_KEYBOARD_SAMSUNG is not set
# CONFIG_KEYBOARD_STOWAWAY is not set
# CONFIG_KEYBOARD_SUNKBD is not set
# CONFIG_KEYBOARD_TM2_TOUCHKEY is not set
# CONFIG_KEYBOARD_XTKBD is not set
CONFIG_INPUT_MOUSE=y
CONFIG_MOUSE_PS2=y
CONFIG_MOUSE_PS2_ALPS=y
CONFIG_MOUSE_PS2_BYD=y
CONFIG_MOUSE_PS2_LOGIPS2PP=y
CONFIG_MOUSE_PS2_SYNAPTICS=y
CONFIG_MOUSE_PS2_SYNAPTICS_SMBUS=y
CONFIG_MOUSE_PS2_CYPRESS=y
CONFIG_MOUSE_PS2_LIFEBOOK=y
CONFIG_MOUSE_PS2_TRACKPOINT=y
# CONFIG_MOUSE_PS2_ELANTECH is not set
# CONFIG_MOUSE_PS2_SENTELIC is not set
# CONFIG_MOUSE_PS2_TOUCHKIT is not set
CONFIG_MOUSE_PS2_FOCALTECH=y
# CONFIG_MOUSE_PS2_VMMOUSE is not set
CONFIG_MOUSE_PS2_SMBUS=y
# CONFIG_MOUSE_SERIAL is not set
# CONFIG_MOUSE_CYAPA is not set
# CONFIG_MOUSE_ELAN_I2C is not set
# CONFIG_MOUSE_VSXXXAA is not set
# CONFIG_MOUSE_SYNAPTICS_I2C is not set
# CONFIG_INPUT_JOYSTICK is not set
# CONFIG_INPUT_TABLET is not set
# CONFIG_INPUT_TOUCHSCREEN is not set
# CONFIG_INPUT_MISC is not set
# CONFIG_RMI4_CORE is not set

#
# Hardware I/O ports
#
CONFIG_SERIO=y
CONFIG_ARCH_MIGHT_HAVE_PC_SERIO=y
CONFIG_SERIO_I8042=y
CONFIG_SERIO_SERPORT=y
# CONFIG_SERIO_CT82C710 is not set
# CONFIG_SERIO_PCIPS2 is not set
CONFIG_SERIO_LIBPS2=y
# CONFIG_SERIO_RAW is not set
# CONFIG_SERIO_ALTERA_PS2 is not set
# CONFIG_SERIO_PS2MULT is not set
# CONFIG_SERIO_ARC_PS2 is not set
# CONFIG_USERIO is not set
# CONFIG_GAMEPORT is not set

#
# Character devices
#
CONFIG_TTY=y
CONFIG_VT=y
CONFIG_CONSOLE_TRANSLATIONS=y
CONFIG_VT_CONSOLE=y
CONFIG_HW_CONSOLE=y
CONFIG_VT_HW_CONSOLE_BINDING=y
CONFIG_UNIX98_PTYS=y
# CONFIG_LEGACY_PTYS is not set
# CONFIG_SERIAL_NONSTANDARD is not set
# CONFIG_NOZOMI is not set
# CONFIG_N_GSM is not set
# CONFIG_TRACE_SINK is not set
CONFIG_DEVMEM=y
CONFIG_DEVKMEM=y

#
# Serial drivers
#
CONFIG_SERIAL_EARLYCON=y
CONFIG_SERIAL_8250=y
CONFIG_SERIAL_8250_DEPRECATED_OPTIONS=y
CONFIG_SERIAL_8250_PNP=y
# CONFIG_SERIAL_8250_FINTEK is not set
CONFIG_SERIAL_8250_CONSOLE=y
CONFIG_SERIAL_8250_DMA=y
CONFIG_SERIAL_8250_PCI=y
CONFIG_SERIAL_8250_EXAR=y
CONFIG_SERIAL_8250_NR_UARTS=32
CONFIG_SERIAL_8250_RUNTIME_UARTS=4
CONFIG_SERIAL_8250_EXTENDED=y
CONFIG_SERIAL_8250_MANY_PORTS=y
CONFIG_SERIAL_8250_SHARE_IRQ=y
CONFIG_SERIAL_8250_DETECT_IRQ=y
CONFIG_SERIAL_8250_RSA=y
# CONFIG_SERIAL_8250_DW is not set
# CONFIG_SERIAL_8250_RT288X is not set
# CONFIG_SERIAL_8250_LPSS is not set
# CONFIG_SERIAL_8250_MID is not set
# CONFIG_SERIAL_8250_MOXA is not set

#
# Non-8250 serial port support
#
# CONFIG_SERIAL_UARTLITE is not set
CONFIG_SERIAL_CORE=y
CONFIG_SERIAL_CORE_CONSOLE=y
# CONFIG_SERIAL_JSM is not set
# CONFIG_SERIAL_SCCNXP is not set
# CONFIG_SERIAL_SC16IS7XX is not set
# CONFIG_SERIAL_ALTERA_JTAGUART is not set
# CONFIG_SERIAL_ALTERA_UART is not set
# CONFIG_SERIAL_ARC is not set
# CONFIG_SERIAL_RP2 is not set
# CONFIG_SERIAL_FSL_LPUART is not set
# CONFIG_SERIAL_DEV_BUS is not set
# CONFIG_TTY_PRINTK is not set
CONFIG_HVC_DRIVER=y
CONFIG_VIRTIO_CONSOLE=y
# CONFIG_IPMI_HANDLER is not set
CONFIG_HW_RANDOM=y
# CONFIG_HW_RANDOM_TIMERIOMEM is not set
# CONFIG_HW_RANDOM_INTEL is not set
# CONFIG_HW_RANDOM_AMD is not set
CONFIG_HW_RANDOM_VIA=y
CONFIG_HW_RANDOM_VIRTIO=y
CONFIG_NVRAM=y
# CONFIG_R3964 is not set
# CONFIG_APPLICOM is not set
# CONFIG_MWAVE is not set
# CONFIG_RAW_DRIVER is not set
CONFIG_HPET=y
# CONFIG_HPET_MMAP is not set
# CONFIG_HANGCHECK_TIMER is not set
# CONFIG_TCG_TPM is not set
# CONFIG_TELCLOCK is not set
CONFIG_DEVPORT=y
# CONFIG_XILLYBUS is not set

#
# I2C support
#
CONFIG_I2C=y
CONFIG_ACPI_I2C_OPREGION=y
CONFIG_I2C_BOARDINFO=y
CONFIG_I2C_COMPAT=y
# CONFIG_I2C_CHARDEV is not set
# CONFIG_I2C_MUX is not set
CONFIG_I2C_HELPER_AUTO=y
CONFIG_I2C_SMBUS=y

#
# I2C Hardware Bus support
#

#
# PC SMBus host controller drivers
#
# CONFIG_I2C_ALI1535 is not set
# CONFIG_I2C_ALI1563 is not set
# CONFIG_I2C_ALI15X3 is not set
# CONFIG_I2C_AMD756 is not set
# CONFIG_I2C_AMD8111 is not set
CONFIG_I2C_I801=y
# CONFIG_I2C_ISCH is not set
# CONFIG_I2C_ISMT is not set
# CONFIG_I2C_PIIX4 is not set
# CONFIG_I2C_NFORCE2 is not set
# CONFIG_I2C_SIS5595 is not set
# CONFIG_I2C_SIS630 is not set
# CONFIG_I2C_SIS96X is not set
# CONFIG_I2C_VIA is not set
# CONFIG_I2C_VIAPRO is not set

#
# ACPI drivers
#
# CONFIG_I2C_SCMI is not set

#
# I2C system bus drivers (mostly embedded / system-on-chip)
#
# CONFIG_I2C_DESIGNWARE_PLATFORM is not set
# CONFIG_I2C_DESIGNWARE_PCI is not set
# CONFIG_I2C_EMEV2 is not set
# CONFIG_I2C_OCORES is not set
# CONFIG_I2C_PCA_PLATFORM is not set
# CONFIG_I2C_SIMTEC is not set
# CONFIG_I2C_XILINX is not set

#
# External I2C/SMBus adapter drivers
#
# CONFIG_I2C_PARPORT_LIGHT is not set
# CONFIG_I2C_TAOS_EVM is not set

#
# Other I2C/SMBus bus drivers
#
# CONFIG_I2C_MLXCPLD is not set
# CONFIG_I2C_SLAVE is not set
# CONFIG_I2C_DEBUG_CORE is not set
# CONFIG_I2C_DEBUG_ALGO is not set
# CONFIG_I2C_DEBUG_BUS is not set
# CONFIG_SPI is not set
# CONFIG_SPMI is not set
# CONFIG_HSI is not set
# CONFIG_PPS is not set

#
# PTP clock support
#
# CONFIG_PTP_1588_CLOCK is not set

#
# Enable PHYLIB and NETWORK_PHY_TIMESTAMPING to see the additional clocks.
#
# CONFIG_PINCTRL is not set
# CONFIG_GPIOLIB is not set
# CONFIG_W1 is not set
# CONFIG_POWER_AVS is not set
# CONFIG_POWER_RESET is not set
CONFIG_POWER_SUPPLY=y
# CONFIG_POWER_SUPPLY_DEBUG is not set
# CONFIG_PDA_POWER is not set
# CONFIG_TEST_POWER is not set
# CONFIG_BATTERY_DS2780 is not set
# CONFIG_BATTERY_DS2781 is not set
# CONFIG_BATTERY_DS2782 is not set
# CONFIG_BATTERY_SBS is not set
# CONFIG_CHARGER_SBS is not set
# CONFIG_BATTERY_BQ27XXX is not set
# CONFIG_BATTERY_MAX17040 is not set
# CONFIG_BATTERY_MAX17042 is not set
# CONFIG_CHARGER_MAX8903 is not set
# CONFIG_CHARGER_LP8727 is not set
# CONFIG_CHARGER_BQ2415X is not set
# CONFIG_CHARGER_SMB347 is not set
# CONFIG_BATTERY_GAUGE_LTC2941 is not set
CONFIG_HWMON=y
# CONFIG_HWMON_DEBUG_CHIP is not set

#
# Native drivers
#
# CONFIG_SENSORS_ABITUGURU is not set
# CONFIG_SENSORS_ABITUGURU3 is not set
# CONFIG_SENSORS_AD7414 is not set
# CONFIG_SENSORS_AD7418 is not set
# CONFIG_SENSORS_ADM1021 is not set
# CONFIG_SENSORS_ADM1025 is not set
# CONFIG_SENSORS_ADM1026 is not set
# CONFIG_SENSORS_ADM1029 is not set
# CONFIG_SENSORS_ADM1031 is not set
# CONFIG_SENSORS_ADM9240 is not set
# CONFIG_SENSORS_ADT7410 is not set
# CONFIG_SENSORS_ADT7411 is not set
# CONFIG_SENSORS_ADT7462 is not set
# CONFIG_SENSORS_ADT7470 is not set
# CONFIG_SENSORS_ADT7475 is not set
# CONFIG_SENSORS_ASC7621 is not set
# CONFIG_SENSORS_K8TEMP is not set
CONFIG_SENSORS_K10TEMP=y
# CONFIG_SENSORS_FAM15H_POWER is not set
# CONFIG_SENSORS_APPLESMC is not set
# CONFIG_SENSORS_ASB100 is not set
# CONFIG_SENSORS_ASPEED is not set
# CONFIG_SENSORS_ATXP1 is not set
# CONFIG_SENSORS_DS620 is not set
# CONFIG_SENSORS_DS1621 is not set
# CONFIG_SENSORS_DELL_SMM is not set
# CONFIG_SENSORS_I5K_AMB is not set
# CONFIG_SENSORS_F71805F is not set
# CONFIG_SENSORS_F71882FG is not set
# CONFIG_SENSORS_F75375S is not set
# CONFIG_SENSORS_FSCHMD is not set
# CONFIG_SENSORS_FTSTEUTATES is not set
# CONFIG_SENSORS_GL518SM is not set
# CONFIG_SENSORS_GL520SM is not set
# CONFIG_SENSORS_G760A is not set
# CONFIG_SENSORS_G762 is not set
# CONFIG_SENSORS_HIH6130 is not set
# CONFIG_SENSORS_I5500 is not set
# CONFIG_SENSORS_CORETEMP is not set
# CONFIG_SENSORS_IT87 is not set
# CONFIG_SENSORS_JC42 is not set
# CONFIG_SENSORS_POWR1220 is not set
# CONFIG_SENSORS_LINEAGE is not set
# CONFIG_SENSORS_LTC2945 is not set
# CONFIG_SENSORS_LTC2990 is not set
# CONFIG_SENSORS_LTC4151 is not set
# CONFIG_SENSORS_LTC4215 is not set
# CONFIG_SENSORS_LTC4222 is not set
# CONFIG_SENSORS_LTC4245 is not set
# CONFIG_SENSORS_LTC4260 is not set
# CONFIG_SENSORS_LTC4261 is not set
# CONFIG_SENSORS_MAX16065 is not set
# CONFIG_SENSORS_MAX1619 is not set
# CONFIG_SENSORS_MAX1668 is not set
# CONFIG_SENSORS_MAX197 is not set
# CONFIG_SENSORS_MAX6621 is not set
# CONFIG_SENSORS_MAX6639 is not set
# CONFIG_SENSORS_MAX6642 is not set
# CONFIG_SENSORS_MAX6650 is not set
# CONFIG_SENSORS_MAX6697 is not set
# CONFIG_SENSORS_MAX31790 is not set
# CONFIG_SENSORS_MCP3021 is not set
# CONFIG_SENSORS_TC654 is not set
# CONFIG_SENSORS_LM63 is not set
# CONFIG_SENSORS_LM73 is not set
# CONFIG_SENSORS_LM75 is not set
# CONFIG_SENSORS_LM77 is not set
# CONFIG_SENSORS_LM78 is not set
# CONFIG_SENSORS_LM80 is not set
# CONFIG_SENSORS_LM83 is not set
# CONFIG_SENSORS_LM85 is not set
# CONFIG_SENSORS_LM87 is not set
# CONFIG_SENSORS_LM90 is not set
# CONFIG_SENSORS_LM92 is not set
# CONFIG_SENSORS_LM93 is not set
# CONFIG_SENSORS_LM95234 is not set
# CONFIG_SENSORS_LM95241 is not set
# CONFIG_SENSORS_LM95245 is not set
# CONFIG_SENSORS_PC87360 is not set
# CONFIG_SENSORS_PC87427 is not set
# CONFIG_SENSORS_NTC_THERMISTOR is not set
# CONFIG_SENSORS_NCT6683 is not set
# CONFIG_SENSORS_NCT6775 is not set
# CONFIG_SENSORS_NCT7802 is not set
# CONFIG_SENSORS_NCT7904 is not set
# CONFIG_SENSORS_PCF8591 is not set
# CONFIG_PMBUS is not set
# CONFIG_SENSORS_SHT21 is not set
# CONFIG_SENSORS_SHT3x is not set
# CONFIG_SENSORS_SHTC1 is not set
# CONFIG_SENSORS_SIS5595 is not set
# CONFIG_SENSORS_DME1737 is not set
# CONFIG_SENSORS_EMC1403 is not set
# CONFIG_SENSORS_EMC2103 is not set
# CONFIG_SENSORS_EMC6W201 is not set
# CONFIG_SENSORS_SMSC47M1 is not set
# CONFIG_SENSORS_SMSC47M192 is not set
# CONFIG_SENSORS_SMSC47B397 is not set
# CONFIG_SENSORS_SCH5627 is not set
# CONFIG_SENSORS_SCH5636 is not set
# CONFIG_SENSORS_STTS751 is not set
# CONFIG_SENSORS_SMM665 is not set
# CONFIG_SENSORS_ADC128D818 is not set
# CONFIG_SENSORS_ADS1015 is not set
# CONFIG_SENSORS_ADS7828 is not set
# CONFIG_SENSORS_AMC6821 is not set
# CONFIG_SENSORS_INA209 is not set
# CONFIG_SENSORS_INA2XX is not set
# CONFIG_SENSORS_INA3221 is not set
# CONFIG_SENSORS_TC74 is not set
# CONFIG_SENSORS_THMC50 is not set
# CONFIG_SENSORS_TMP102 is not set
# CONFIG_SENSORS_TMP103 is not set
# CONFIG_SENSORS_TMP108 is not set
# CONFIG_SENSORS_TMP401 is not set
# CONFIG_SENSORS_TMP421 is not set
# CONFIG_SENSORS_VIA_CPUTEMP is not set
# CONFIG_SENSORS_VIA686A is not set
# CONFIG_SENSORS_VT1211 is not set
# CONFIG_SENSORS_VT8231 is not set
# CONFIG_SENSORS_W83773G is not set
# CONFIG_SENSORS_W83781D is not set
# CONFIG_SENSORS_W83791D is not set
# CONFIG_SENSORS_W83792D is not set
# CONFIG_SENSORS_W83793 is not set
# CONFIG_SENSORS_W83795 is not set
# CONFIG_SENSORS_W83L785TS is not set
# CONFIG_SENSORS_W83L786NG is not set
# CONFIG_SENSORS_W83627HF is not set
# CONFIG_SENSORS_W83627EHF is not set
# CONFIG_SENSORS_XGENE is not set

#
# ACPI drivers
#
# CONFIG_SENSORS_ACPI_POWER is not set
# CONFIG_SENSORS_ATK0110 is not set
CONFIG_THERMAL=y
# CONFIG_THERMAL_STATISTICS is not set
CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS=0
CONFIG_THERMAL_HWMON=y
CONFIG_THERMAL_WRITABLE_TRIPS=y
CONFIG_THERMAL_DEFAULT_GOV_STEP_WISE=y
# CONFIG_THERMAL_DEFAULT_GOV_FAIR_SHARE is not set
# CONFIG_THERMAL_DEFAULT_GOV_USER_SPACE is not set
# CONFIG_THERMAL_DEFAULT_GOV_POWER_ALLOCATOR is not set
# CONFIG_THERMAL_GOV_FAIR_SHARE is not set
CONFIG_THERMAL_GOV_STEP_WISE=y
# CONFIG_THERMAL_GOV_BANG_BANG is not set
CONFIG_THERMAL_GOV_USER_SPACE=y
# CONFIG_THERMAL_GOV_POWER_ALLOCATOR is not set
# CONFIG_THERMAL_EMULATION is not set
# CONFIG_INTEL_POWERCLAMP is not set
CONFIG_X86_PKG_TEMP_THERMAL=y
# CONFIG_INTEL_SOC_DTS_THERMAL is not set

#
# ACPI INT340X thermal drivers
#
# CONFIG_INT340X_THERMAL is not set
# CONFIG_INTEL_PCH_THERMAL is not set
CONFIG_WATCHDOG=y
# CONFIG_WATCHDOG_CORE is not set
# CONFIG_WATCHDOG_NOWAYOUT is not set
CONFIG_WATCHDOG_HANDLE_BOOT_ENABLED=y
# CONFIG_WATCHDOG_SYSFS is not set

#
# Watchdog Device Drivers
#
# CONFIG_SOFT_WATCHDOG is not set
# CONFIG_WDAT_WDT is not set
# CONFIG_XILINX_WATCHDOG is not set
# CONFIG_ZIIRAVE_WATCHDOG is not set
# CONFIG_CADENCE_WATCHDOG is not set
# CONFIG_DW_WATCHDOG is not set
# CONFIG_MAX63XX_WATCHDOG is not set
# CONFIG_ACQUIRE_WDT is not set
# CONFIG_ADVANTECH_WDT is not set
# CONFIG_ALIM1535_WDT is not set
# CONFIG_ALIM7101_WDT is not set
# CONFIG_EBC_C384_WDT is not set
# CONFIG_F71808E_WDT is not set
# CONFIG_SP5100_TCO is not set
# CONFIG_SBC_FITPC2_WATCHDOG is not set
# CONFIG_EUROTECH_WDT is not set
# CONFIG_IB700_WDT is not set
# CONFIG_IBMASR is not set
# CONFIG_WAFER_WDT is not set
# CONFIG_I6300ESB_WDT is not set
# CONFIG_IE6XX_WDT is not set
# CONFIG_ITCO_WDT is not set
# CONFIG_IT8712F_WDT is not set
# CONFIG_IT87_WDT is not set
# CONFIG_HP_WATCHDOG is not set
# CONFIG_SC1200_WDT is not set
# CONFIG_PC87413_WDT is not set
# CONFIG_NV_TCO is not set
# CONFIG_60XX_WDT is not set
# CONFIG_CPU5_WDT is not set
# CONFIG_SMSC_SCH311X_WDT is not set
# CONFIG_SMSC37B787_WDT is not set
# CONFIG_VIA_WDT is not set
# CONFIG_W83627HF_WDT is not set
# CONFIG_W83877F_WDT is not set
# CONFIG_W83977F_WDT is not set
# CONFIG_MACHZ_WDT is not set
# CONFIG_SBC_EPX_C3_WATCHDOG is not set
# CONFIG_NI903X_WDT is not set
# CONFIG_NIC7018_WDT is not set

#
# PCI-based Watchdog Cards
#
# CONFIG_PCIPCWATCHDOG is not set
# CONFIG_WDTPCI is not set

#
# Watchdog Pretimeout Governors
#
# CONFIG_WATCHDOG_PRETIMEOUT_GOV is not set
CONFIG_SSB_POSSIBLE=y
# CONFIG_SSB is not set
CONFIG_BCMA_POSSIBLE=y
# CONFIG_BCMA is not set

#
# Multifunction device drivers
#
# CONFIG_MFD_AS3711 is not set
# CONFIG_PMIC_ADP5520 is not set
# CONFIG_MFD_BCM590XX is not set
# CONFIG_MFD_BD9571MWV is not set
# CONFIG_MFD_AXP20X_I2C is not set
# CONFIG_MFD_CROS_EC is not set
# CONFIG_PMIC_DA903X is not set
# CONFIG_MFD_DA9052_I2C is not set
# CONFIG_MFD_DA9055 is not set
# CONFIG_MFD_DA9062 is not set
# CONFIG_MFD_DA9063 is not set
# CONFIG_MFD_DA9150 is not set
# CONFIG_MFD_MC13XXX_I2C is not set
# CONFIG_HTC_PASIC3 is not set
# CONFIG_MFD_INTEL_QUARK_I2C_GPIO is not set
# CONFIG_LPC_ICH is not set
# CONFIG_LPC_SCH is not set
# CONFIG_INTEL_SOC_PMIC_CHTWC is not set
# CONFIG_MFD_INTEL_LPSS_ACPI is not set
# CONFIG_MFD_INTEL_LPSS_PCI is not set
# CONFIG_MFD_JANZ_CMODIO is not set
# CONFIG_MFD_KEMPLD is not set
# CONFIG_MFD_88PM800 is not set
# CONFIG_MFD_88PM805 is not set
# CONFIG_MFD_88PM860X is not set
# CONFIG_MFD_MAX14577 is not set
# CONFIG_MFD_MAX77693 is not set
# CONFIG_MFD_MAX77843 is not set
# CONFIG_MFD_MAX8907 is not set
# CONFIG_MFD_MAX8925 is not set
# CONFIG_MFD_MAX8997 is not set
# CONFIG_MFD_MAX8998 is not set
# CONFIG_MFD_MT6397 is not set
# CONFIG_MFD_MENF21BMC is not set
# CONFIG_MFD_RETU is not set
# CONFIG_MFD_PCF50633 is not set
# CONFIG_MFD_RDC321X is not set
# CONFIG_MFD_RT5033 is not set
# CONFIG_MFD_RC5T583 is not set
# CONFIG_MFD_SEC_CORE is not set
# CONFIG_MFD_SI476X_CORE is not set
# CONFIG_MFD_SM501 is not set
# CONFIG_MFD_SKY81452 is not set
# CONFIG_MFD_SMSC is not set
# CONFIG_ABX500_CORE is not set
# CONFIG_MFD_SYSCON is not set
# CONFIG_MFD_TI_AM335X_TSCADC is not set
# CONFIG_MFD_LP3943 is not set
# CONFIG_MFD_LP8788 is not set
# CONFIG_MFD_TI_LMU is not set
# CONFIG_MFD_PALMAS is not set
# CONFIG_TPS6105X is not set
# CONFIG_TPS6507X is not set
# CONFIG_MFD_TPS65086 is not set
# CONFIG_MFD_TPS65090 is not set
# CONFIG_MFD_TPS68470 is not set
# CONFIG_MFD_TI_LP873X is not set
# CONFIG_MFD_TPS6586X is not set
# CONFIG_MFD_TPS65912_I2C is not set
# CONFIG_MFD_TPS80031 is not set
# CONFIG_TWL4030_CORE is not set
# CONFIG_TWL6040_CORE is not set
# CONFIG_MFD_WL1273_CORE is not set
# CONFIG_MFD_LM3533 is not set
# CONFIG_MFD_VX855 is not set
# CONFIG_MFD_ARIZONA_I2C is not set
# CONFIG_MFD_WM8400 is not set
# CONFIG_MFD_WM831X_I2C is not set
# CONFIG_MFD_WM8350_I2C is not set
# CONFIG_MFD_WM8994 is not set
# CONFIG_REGULATOR is not set
CONFIG_RC_CORE=y
# CONFIG_RC_MAP is not set
# CONFIG_LIRC is not set
# CONFIG_RC_DECODERS is not set
# CONFIG_RC_DEVICES is not set
# CONFIG_MEDIA_SUPPORT is not set

#
# Graphics support
#
# CONFIG_AGP is not set
CONFIG_VGA_ARB=y
CONFIG_VGA_ARB_MAX_GPUS=16
# CONFIG_VGA_SWITCHEROO is not set
# CONFIG_DRM is not set

#
# ACP (Audio CoProcessor) Configuration
#

#
# AMD Library routines
#
CONFIG_DRM_PANEL_ORIENTATION_QUIRKS=y

#
# Frame buffer Devices
#
CONFIG_FB=y
# CONFIG_FIRMWARE_EDID is not set
CONFIG_FB_CMDLINE=y
CONFIG_FB_NOTIFY=y
CONFIG_FB_CFB_FILLRECT=y
CONFIG_FB_CFB_COPYAREA=y
CONFIG_FB_CFB_IMAGEBLIT=y
# CONFIG_FB_FOREIGN_ENDIAN is not set
CONFIG_FB_MODE_HELPERS=y
CONFIG_FB_TILEBLITTING=y

#
# Frame buffer hardware drivers
#
# CONFIG_FB_CIRRUS is not set
# CONFIG_FB_PM2 is not set
# CONFIG_FB_CYBER2000 is not set
# CONFIG_FB_ARC is not set
# CONFIG_FB_ASILIANT is not set
# CONFIG_FB_IMSTT is not set
# CONFIG_FB_VGA16 is not set
# CONFIG_FB_UVESA is not set
# CONFIG_FB_VESA is not set
CONFIG_FB_EFI=y
# CONFIG_FB_N411 is not set
# CONFIG_FB_HGA is not set
# CONFIG_FB_OPENCORES is not set
# CONFIG_FB_S1D13XXX is not set
# CONFIG_FB_NVIDIA is not set
# CONFIG_FB_RIVA is not set
# CONFIG_FB_I740 is not set
# CONFIG_FB_LE80578 is not set
# CONFIG_FB_MATROX is not set
# CONFIG_FB_RADEON is not set
# CONFIG_FB_ATY128 is not set
# CONFIG_FB_ATY is not set
# CONFIG_FB_S3 is not set
# CONFIG_FB_SAVAGE is not set
# CONFIG_FB_SIS is not set
# CONFIG_FB_NEOMAGIC is not set
# CONFIG_FB_KYRO is not set
# CONFIG_FB_3DFX is not set
# CONFIG_FB_VOODOO1 is not set
# CONFIG_FB_VT8623 is not set
# CONFIG_FB_TRIDENT is not set
# CONFIG_FB_ARK is not set
# CONFIG_FB_PM3 is not set
# CONFIG_FB_CARMINE is not set
# CONFIG_FB_IBM_GXT4500 is not set
# CONFIG_FB_VIRTUAL is not set
# CONFIG_FB_METRONOME is not set
# CONFIG_FB_MB862XX is not set
# CONFIG_FB_BROADSHEET is not set
# CONFIG_FB_AUO_K190X is not set
# CONFIG_FB_SIMPLE is not set
# CONFIG_FB_SM712 is not set
# CONFIG_BACKLIGHT_LCD_SUPPORT is not set

#
# Console display driver support
#
CONFIG_VGA_CONSOLE=y
CONFIG_VGACON_SOFT_SCROLLBACK=y
CONFIG_VGACON_SOFT_SCROLLBACK_SIZE=64
# CONFIG_VGACON_SOFT_SCROLLBACK_PERSISTENT_ENABLE_BY_DEFAULT is not set
CONFIG_DUMMY_CONSOLE=y
CONFIG_DUMMY_CONSOLE_COLUMNS=80
CONFIG_DUMMY_CONSOLE_ROWS=25
CONFIG_FRAMEBUFFER_CONSOLE=y
CONFIG_FRAMEBUFFER_CONSOLE_DETECT_PRIMARY=y
# CONFIG_FRAMEBUFFER_CONSOLE_ROTATION is not set
# CONFIG_LOGO is not set
# CONFIG_SOUND is not set

#
# HID support
#
CONFIG_HID=y
# CONFIG_HID_BATTERY_STRENGTH is not set
CONFIG_HIDRAW=y
# CONFIG_UHID is not set
CONFIG_HID_GENERIC=y

#
# Special HID drivers
#
CONFIG_HID_A4TECH=y
# CONFIG_HID_ACRUX is not set
CONFIG_HID_APPLE=y
# CONFIG_HID_ASUS is not set
# CONFIG_HID_AUREAL is not set
CONFIG_HID_BELKIN=y
CONFIG_HID_CHERRY=y
CONFIG_HID_CHICONY=y
# CONFIG_HID_CMEDIA is not set
CONFIG_HID_CYPRESS=y
CONFIG_HID_DRAGONRISE=y
# CONFIG_DRAGONRISE_FF is not set
# CONFIG_HID_EMS_FF is not set
# CONFIG_HID_ELECOM is not set
CONFIG_HID_EZKEY=y
# CONFIG_HID_GEMBIRD is not set
# CONFIG_HID_GFRM is not set
# CONFIG_HID_KEYTOUCH is not set
CONFIG_HID_KYE=y
# CONFIG_HID_WALTOP is not set
CONFIG_HID_GYRATION=y
# CONFIG_HID_ICADE is not set
# CONFIG_HID_ITE is not set
# CONFIG_HID_JABRA is not set
CONFIG_HID_TWINHAN=y
CONFIG_HID_KENSINGTON=y
# CONFIG_HID_LCPOWER is not set
# CONFIG_HID_LED is not set
# CONFIG_HID_LENOVO is not set
CONFIG_HID_LOGITECH=y
CONFIG_HID_LOGITECH_DJ=y
CONFIG_HID_LOGITECH_HIDPP=y
CONFIG_LOGITECH_FF=y
# CONFIG_LOGIRUMBLEPAD2_FF is not set
# CONFIG_LOGIG940_FF is not set
CONFIG_LOGIWHEELS_FF=y
# CONFIG_HID_MAGICMOUSE is not set
# CONFIG_HID_MAYFLASH is not set
CONFIG_HID_MICROSOFT=y
CONFIG_HID_MONTEREY=y
# CONFIG_HID_MULTITOUCH is not set
# CONFIG_HID_NTI is not set
CONFIG_HID_ORTEK=y
CONFIG_HID_PANTHERLORD=y
CONFIG_PANTHERLORD_FF=y
CONFIG_HID_PETALYNX=y
# CONFIG_HID_PICOLCD is not set
# CONFIG_HID_PLANTRONICS is not set
# CONFIG_HID_PRIMAX is not set
# CONFIG_HID_SAITEK is not set
CONFIG_HID_SAMSUNG=y
# CONFIG_HID_SPEEDLINK is not set
# CONFIG_HID_STEELSERIES is not set
CONFIG_HID_SUNPLUS=y
# CONFIG_HID_RMI is not set
CONFIG_HID_GREENASIA=y
# CONFIG_GREENASIA_FF is not set
CONFIG_HID_SMARTJOYPLUS=y
# CONFIG_SMARTJOYPLUS_FF is not set
# CONFIG_HID_TIVO is not set
CONFIG_HID_TOPSEED=y
# CONFIG_HID_THINGM is not set
CONFIG_HID_THRUSTMASTER=y
CONFIG_THRUSTMASTER_FF=y
# CONFIG_HID_UDRAW_PS3 is not set
# CONFIG_HID_WIIMOTE is not set
# CONFIG_HID_XINMO is not set
CONFIG_HID_ZEROPLUS=y
CONFIG_ZEROPLUS_FF=y
# CONFIG_HID_ZYDACRON is not set
# CONFIG_HID_SENSOR_HUB is not set
# CONFIG_HID_ALPS is not set

#
# I2C HID support
#
# CONFIG_I2C_HID is not set

#
# Intel ISH HID support
#
# CONFIG_INTEL_ISH_HID is not set
CONFIG_USB_OHCI_LITTLE_ENDIAN=y
# CONFIG_USB_SUPPORT is not set
# CONFIG_UWB is not set
# CONFIG_MMC is not set
# CONFIG_MEMSTICK is not set
CONFIG_NEW_LEDS=y
CONFIG_LEDS_CLASS=y
# CONFIG_LEDS_CLASS_FLASH is not set
# CONFIG_LEDS_BRIGHTNESS_HW_CHANGED is not set

#
# LED drivers
#
# CONFIG_LEDS_APU is not set
# CONFIG_LEDS_LM3530 is not set
# CONFIG_LEDS_LM3642 is not set
# CONFIG_LEDS_PCA9532 is not set
# CONFIG_LEDS_LP3944 is not set
# CONFIG_LEDS_LP5521 is not set
# CONFIG_LEDS_LP5523 is not set
# CONFIG_LEDS_LP5562 is not set
# CONFIG_LEDS_LP8501 is not set
# CONFIG_LEDS_CLEVO_MAIL is not set
# CONFIG_LEDS_PCA955X is not set
# CONFIG_LEDS_PCA963X is not set
# CONFIG_LEDS_BD2802 is not set
# CONFIG_LEDS_INTEL_SS4200 is not set
# CONFIG_LEDS_TCA6507 is not set
# CONFIG_LEDS_TLC591XX is not set
# CONFIG_LEDS_LM355x is not set

#
# LED driver for blink(1) USB RGB LED is under Special HID drivers (HID_THINGM)
#
# CONFIG_LEDS_BLINKM is not set
# CONFIG_LEDS_MLXCPLD is not set
# CONFIG_LEDS_MLXREG is not set
# CONFIG_LEDS_USER is not set
# CONFIG_LEDS_NIC78BX is not set

#
# LED Triggers
#
CONFIG_LEDS_TRIGGERS=y
# CONFIG_LEDS_TRIGGER_TIMER is not set
# CONFIG_LEDS_TRIGGER_ONESHOT is not set
# CONFIG_LEDS_TRIGGER_DISK is not set
# CONFIG_LEDS_TRIGGER_HEARTBEAT is not set
# CONFIG_LEDS_TRIGGER_BACKLIGHT is not set
# CONFIG_LEDS_TRIGGER_CPU is not set
# CONFIG_LEDS_TRIGGER_ACTIVITY is not set
# CONFIG_LEDS_TRIGGER_DEFAULT_ON is not set

#
# iptables trigger is under Netfilter config (LED target)
#
# CONFIG_LEDS_TRIGGER_TRANSIENT is not set
# CONFIG_LEDS_TRIGGER_CAMERA is not set
# CONFIG_LEDS_TRIGGER_PANIC is not set
# CONFIG_LEDS_TRIGGER_NETDEV is not set
# CONFIG_ACCESSIBILITY is not set
# CONFIG_INFINIBAND is not set
CONFIG_EDAC_ATOMIC_SCRUB=y
CONFIG_EDAC_SUPPORT=y
CONFIG_EDAC=y
CONFIG_EDAC_LEGACY_SYSFS=y
# CONFIG_EDAC_DEBUG is not set
CONFIG_EDAC_DECODE_MCE=y
# CONFIG_EDAC_AMD64 is not set
# CONFIG_EDAC_E752X is not set
# CONFIG_EDAC_I82975X is not set
# CONFIG_EDAC_I3000 is not set
# CONFIG_EDAC_I3200 is not set
# CONFIG_EDAC_IE31200 is not set
# CONFIG_EDAC_X38 is not set
# CONFIG_EDAC_I5400 is not set
# CONFIG_EDAC_I7CORE is not set
# CONFIG_EDAC_I5000 is not set
# CONFIG_EDAC_I5100 is not set
# CONFIG_EDAC_I7300 is not set
# CONFIG_EDAC_SBRIDGE is not set
# CONFIG_EDAC_SKX is not set
# CONFIG_EDAC_PND2 is not set
CONFIG_RTC_LIB=y
CONFIG_RTC_MC146818_LIB=y
CONFIG_RTC_CLASS=y
CONFIG_RTC_HCTOSYS=y
CONFIG_RTC_HCTOSYS_DEVICE="rtc0"
CONFIG_RTC_SYSTOHC=y
CONFIG_RTC_SYSTOHC_DEVICE="rtc0"
# CONFIG_RTC_DEBUG is not set
# CONFIG_RTC_NVMEM is not set

#
# RTC interfaces
#
CONFIG_RTC_INTF_SYSFS=y
CONFIG_RTC_INTF_PROC=y
CONFIG_RTC_INTF_DEV=y
# CONFIG_RTC_INTF_DEV_UIE_EMUL is not set
# CONFIG_RTC_DRV_TEST is not set

#
# I2C RTC drivers
#
# CONFIG_RTC_DRV_ABB5ZES3 is not set
# CONFIG_RTC_DRV_ABX80X is not set
# CONFIG_RTC_DRV_DS1307 is not set
# CONFIG_RTC_DRV_DS1374 is not set
# CONFIG_RTC_DRV_DS1672 is not set
# CONFIG_RTC_DRV_MAX6900 is not set
# CONFIG_RTC_DRV_RS5C372 is not set
# CONFIG_RTC_DRV_ISL1208 is not set
# CONFIG_RTC_DRV_ISL12022 is not set
# CONFIG_RTC_DRV_X1205 is not set
# CONFIG_RTC_DRV_PCF8523 is not set
# CONFIG_RTC_DRV_PCF85063 is not set
# CONFIG_RTC_DRV_PCF85363 is not set
# CONFIG_RTC_DRV_PCF8563 is not set
# CONFIG_RTC_DRV_PCF8583 is not set
# CONFIG_RTC_DRV_M41T80 is not set
# CONFIG_RTC_DRV_BQ32K is not set
# CONFIG_RTC_DRV_S35390A is not set
# CONFIG_RTC_DRV_FM3130 is not set
# CONFIG_RTC_DRV_RX8010 is not set
# CONFIG_RTC_DRV_RX8581 is not set
# CONFIG_RTC_DRV_RX8025 is not set
# CONFIG_RTC_DRV_EM3027 is not set
# CONFIG_RTC_DRV_RV8803 is not set

#
# SPI RTC drivers
#
CONFIG_RTC_I2C_AND_SPI=y

#
# SPI and I2C RTC drivers
#
# CONFIG_RTC_DRV_DS3232 is not set
# CONFIG_RTC_DRV_PCF2127 is not set
# CONFIG_RTC_DRV_RV3029C2 is not set

#
# Platform RTC drivers
#
CONFIG_RTC_DRV_CMOS=y
# CONFIG_RTC_DRV_DS1286 is not set
# CONFIG_RTC_DRV_DS1511 is not set
# CONFIG_RTC_DRV_DS1553 is not set
# CONFIG_RTC_DRV_DS1685_FAMILY is not set
# CONFIG_RTC_DRV_DS1742 is not set
# CONFIG_RTC_DRV_DS2404 is not set
# CONFIG_RTC_DRV_STK17TA8 is not set
# CONFIG_RTC_DRV_M48T86 is not set
# CONFIG_RTC_DRV_M48T35 is not set
# CONFIG_RTC_DRV_M48T59 is not set
# CONFIG_RTC_DRV_MSM6242 is not set
# CONFIG_RTC_DRV_BQ4802 is not set
# CONFIG_RTC_DRV_RP5C01 is not set
# CONFIG_RTC_DRV_V3020 is not set

#
# on-CPU RTC drivers
#
# CONFIG_RTC_DRV_FTRTC010 is not set

#
# HID Sensor RTC drivers
#
CONFIG_DMADEVICES=y
# CONFIG_DMADEVICES_DEBUG is not set

#
# DMA Devices
#
CONFIG_DMA_ACPI=y
# CONFIG_ALTERA_MSGDMA is not set
# CONFIG_INTEL_IDMA64 is not set
# CONFIG_INTEL_IOATDMA is not set
# CONFIG_QCOM_HIDMA_MGMT is not set
# CONFIG_QCOM_HIDMA is not set
# CONFIG_DW_DMAC is not set
# CONFIG_DW_DMAC_PCI is not set

#
# DMABUF options
#
CONFIG_SYNC_FILE=y
# CONFIG_SW_SYNC is not set
# CONFIG_AUXDISPLAY is not set
# CONFIG_UIO is not set
CONFIG_IRQ_BYPASS_MANAGER=y
CONFIG_VIRT_DRIVERS=y
# CONFIG_VBOXGUEST is not set
CONFIG_VIRTIO=y
CONFIG_VIRTIO_MENU=y
CONFIG_VIRTIO_PCI=y
CONFIG_VIRTIO_PCI_LEGACY=y
CONFIG_VIRTIO_BALLOON=y
CONFIG_VIRTIO_INPUT=y
CONFIG_VIRTIO_MMIO=y
CONFIG_VIRTIO_MMIO_CMDLINE_DEVICES=y

#
# Microsoft Hyper-V guest support
#
# CONFIG_HYPERV is not set
# CONFIG_STAGING is not set
# CONFIG_X86_PLATFORM_DEVICES is not set
CONFIG_PMC_ATOM=y
# CONFIG_CHROME_PLATFORMS is not set
# CONFIG_MELLANOX_PLATFORM is not set
CONFIG_CLKDEV_LOOKUP=y
CONFIG_HAVE_CLK_PREPARE=y
CONFIG_COMMON_CLK=y

#
# Common Clock Framework
#
# CONFIG_COMMON_CLK_SI5351 is not set
# CONFIG_COMMON_CLK_SI544 is not set
# CONFIG_COMMON_CLK_CDCE706 is not set
# CONFIG_COMMON_CLK_CS2000_CP is not set
# CONFIG_HWSPINLOCK is not set

#
# Clock Source drivers
#
CONFIG_CLKEVT_I8253=y
CONFIG_I8253_LOCK=y
CONFIG_CLKBLD_I8253=y
CONFIG_MAILBOX=y
CONFIG_PCC=y
# CONFIG_ALTERA_MBOX is not set
CONFIG_IOMMU_SUPPORT=y

#
# Generic IOMMU Pagetable Support
#
# CONFIG_AMD_IOMMU is not set
# CONFIG_INTEL_IOMMU is not set
# CONFIG_IRQ_REMAP is not set

#
# Remoteproc drivers
#
# CONFIG_REMOTEPROC is not set

#
# Rpmsg drivers
#
# CONFIG_RPMSG_QCOM_GLINK_RPM is not set
# CONFIG_RPMSG_VIRTIO is not set
# CONFIG_SOUNDWIRE is not set

#
# SOC (System On Chip) specific Drivers
#

#
# Amlogic SoC drivers
#

#
# Broadcom SoC drivers
#

#
# i.MX SoC drivers
#

#
# Qualcomm SoC drivers
#
# CONFIG_SOC_TI is not set

#
# Xilinx SoC drivers
#
# CONFIG_XILINX_VCU is not set
# CONFIG_PM_DEVFREQ is not set
# CONFIG_EXTCON is not set
# CONFIG_MEMORY is not set
# CONFIG_IIO is not set
# CONFIG_NTB is not set
# CONFIG_VME_BUS is not set
# CONFIG_PWM is not set

#
# IRQ chip support
#
CONFIG_ARM_GIC_MAX_NR=1
# CONFIG_IPACK_BUS is not set
# CONFIG_RESET_CONTROLLER is not set
# CONFIG_FMC is not set

#
# PHY Subsystem
#
# CONFIG_GENERIC_PHY is not set
# CONFIG_BCM_KONA_USB2_PHY is not set
# CONFIG_PHY_PXA_28NM_HSIC is not set
# CONFIG_PHY_PXA_28NM_USB2 is not set
# CONFIG_POWERCAP is not set
# CONFIG_MCB is not set

#
# Performance monitor support
#
CONFIG_RAS=y
# CONFIG_THUNDERBOLT is not set

#
# Android
#
CONFIG_ANDROID=y
# CONFIG_ANDROID_BINDER_IPC is not set
CONFIG_LIBNVDIMM=y
CONFIG_BLK_DEV_PMEM=y
CONFIG_ND_BLK=y
CONFIG_ND_CLAIM=y
CONFIG_ND_BTT=y
CONFIG_BTT=y
CONFIG_ND_PFN=y
CONFIG_NVDIMM_PFN=y
CONFIG_NVDIMM_DAX=y
CONFIG_DAX_DRIVER=y
CONFIG_DAX=y
CONFIG_DEV_DAX=y
CONFIG_DEV_DAX_PMEM=y
CONFIG_NVMEM=y

#
# HW tracing support
#
# CONFIG_STM is not set
# CONFIG_INTEL_TH is not set
# CONFIG_FPGA is not set
# CONFIG_UNISYS_VISORBUS is not set
# CONFIG_SIOX is not set
# CONFIG_SLIMBUS is not set

#
# Firmware Drivers
#
# CONFIG_EDD is not set
CONFIG_FIRMWARE_MEMMAP=y
# CONFIG_DELL_RBU is not set
# CONFIG_DCDBAS is not set
CONFIG_DMIID=y
# CONFIG_DMI_SYSFS is not set
CONFIG_DMI_SCAN_MACHINE_NON_EFI_FALLBACK=y
# CONFIG_ISCSI_IBFT_FIND is not set
# CONFIG_FW_CFG_SYSFS is not set
# CONFIG_GOOGLE_FIRMWARE is not set

#
# EFI (Extensible Firmware Interface) Support
#
CONFIG_EFI_VARS=y
CONFIG_EFI_ESRT=y
CONFIG_EFI_RUNTIME_MAP=y
# CONFIG_EFI_FAKE_MEMMAP is not set
CONFIG_EFI_RUNTIME_WRAPPERS=y
# CONFIG_EFI_BOOTLOADER_CONTROL is not set
# CONFIG_EFI_CAPSULE_LOADER is not set
# CONFIG_EFI_TEST is not set

#
# Tegra firmware driver
#

#
# File systems
#
CONFIG_DCACHE_WORD_ACCESS=y
CONFIG_FS_IOMAP=y
CONFIG_EXT2_FS=y
CONFIG_EXT2_FS_XATTR=y
CONFIG_EXT2_FS_POSIX_ACL=y
CONFIG_EXT2_FS_SECURITY=y
CONFIG_EXT3_FS=y
CONFIG_EXT3_FS_POSIX_ACL=y
CONFIG_EXT3_FS_SECURITY=y
CONFIG_EXT4_FS=y
CONFIG_EXT4_FS_POSIX_ACL=y
CONFIG_EXT4_FS_SECURITY=y
CONFIG_EXT4_ENCRYPTION=y
CONFIG_EXT4_FS_ENCRYPTION=y
# CONFIG_EXT4_DEBUG is not set
CONFIG_JBD2=y
# CONFIG_JBD2_DEBUG is not set
CONFIG_FS_MBCACHE=y
# CONFIG_REISERFS_FS is not set
# CONFIG_JFS_FS is not set
CONFIG_XFS_FS=y
CONFIG_XFS_QUOTA=y
CONFIG_XFS_POSIX_ACL=y
CONFIG_XFS_RT=y
CONFIG_XFS_ONLINE_SCRUB=y
# CONFIG_XFS_ONLINE_REPAIR is not set
CONFIG_XFS_DEBUG=y
CONFIG_XFS_ASSERT_FATAL=y
# CONFIG_GFS2_FS is not set
# CONFIG_OCFS2_FS is not set
CONFIG_BTRFS_FS=y
CONFIG_BTRFS_FS_POSIX_ACL=y
# CONFIG_BTRFS_FS_CHECK_INTEGRITY is not set
# CONFIG_BTRFS_FS_RUN_SANITY_TESTS is not set
# CONFIG_BTRFS_DEBUG is not set
# CONFIG_BTRFS_ASSERT is not set
CONFIG_BTRFS_FS_REF_VERIFY=y
# CONFIG_NILFS2_FS is not set
CONFIG_F2FS_FS=y
CONFIG_F2FS_STAT_FS=y
CONFIG_F2FS_FS_XATTR=y
CONFIG_F2FS_FS_POSIX_ACL=y
CONFIG_F2FS_FS_SECURITY=y
# CONFIG_F2FS_CHECK_FS is not set
CONFIG_F2FS_FS_ENCRYPTION=y
# CONFIG_F2FS_IO_TRACE is not set
# CONFIG_F2FS_FAULT_INJECTION is not set
CONFIG_FS_DAX=y
CONFIG_FS_DAX_PMD=y
CONFIG_FS_POSIX_ACL=y
CONFIG_EXPORTFS=y
CONFIG_EXPORTFS_BLOCK_OPS=y
CONFIG_FILE_LOCKING=y
CONFIG_MANDATORY_FILE_LOCKING=y
CONFIG_FS_ENCRYPTION=y
CONFIG_FSNOTIFY=y
CONFIG_DNOTIFY=y
CONFIG_INOTIFY_USER=y
CONFIG_FANOTIFY=y
CONFIG_FANOTIFY_ACCESS_PERMISSIONS=y
CONFIG_QUOTA=y
CONFIG_QUOTA_NETLINK_INTERFACE=y
# CONFIG_PRINT_QUOTA_WARNING is not set
# CONFIG_QUOTA_DEBUG is not set
CONFIG_QUOTA_TREE=y
# CONFIG_QFMT_V1 is not set
CONFIG_QFMT_V2=y
CONFIG_QUOTACTL=y
CONFIG_QUOTACTL_COMPAT=y
CONFIG_AUTOFS4_FS=y
CONFIG_FUSE_FS=y
# CONFIG_CUSE is not set
CONFIG_OVERLAY_FS=y
CONFIG_OVERLAY_FS_REDIRECT_DIR=y
CONFIG_OVERLAY_FS_REDIRECT_ALWAYS_FOLLOW=y
CONFIG_OVERLAY_FS_INDEX=y
CONFIG_OVERLAY_FS_NFS_EXPORT=y
# CONFIG_OVERLAY_FS_XINO_AUTO is not set

#
# Caches
#
CONFIG_FSCACHE=y
# CONFIG_FSCACHE_STATS is not set
# CONFIG_FSCACHE_HISTOGRAM is not set
# CONFIG_FSCACHE_DEBUG is not set
# CONFIG_FSCACHE_OBJECT_LIST is not set
CONFIG_CACHEFILES=y
# CONFIG_CACHEFILES_DEBUG is not set
# CONFIG_CACHEFILES_HISTOGRAM is not set

#
# CD-ROM/DVD Filesystems
#
CONFIG_ISO9660_FS=y
CONFIG_JOLIET=y
CONFIG_ZISOFS=y
CONFIG_UDF_FS=y
CONFIG_UDF_NLS=y

#
# DOS/FAT/NT Filesystems
#
CONFIG_FAT_FS=y
CONFIG_MSDOS_FS=y
CONFIG_VFAT_FS=y
CONFIG_FAT_DEFAULT_CODEPAGE=437
CONFIG_FAT_DEFAULT_IOCHARSET="iso8859-1"
# CONFIG_FAT_DEFAULT_UTF8 is not set
CONFIG_NTFS_FS=y
# CONFIG_NTFS_DEBUG is not set
CONFIG_NTFS_RW=y

#
# Pseudo filesystems
#
CONFIG_PROC_FS=y
CONFIG_PROC_KCORE=y
CONFIG_PROC_VMCORE=y
CONFIG_PROC_SYSCTL=y
CONFIG_PROC_PAGE_MONITOR=y
# CONFIG_PROC_CHILDREN is not set
CONFIG_KERNFS=y
CONFIG_SYSFS=y
CONFIG_TMPFS=y
CONFIG_TMPFS_POSIX_ACL=y
CONFIG_TMPFS_XATTR=y
CONFIG_HUGETLBFS=y
CONFIG_HUGETLB_PAGE=y
CONFIG_ARCH_HAS_GIGANTIC_PAGE=y
CONFIG_CONFIGFS_FS=y
# CONFIG_EFIVAR_FS is not set
CONFIG_MISC_FILESYSTEMS=y
# CONFIG_ORANGEFS_FS is not set
# CONFIG_ADFS_FS is not set
# CONFIG_AFFS_FS is not set
# CONFIG_ECRYPT_FS is not set
# CONFIG_HFS_FS is not set
# CONFIG_HFSPLUS_FS is not set
# CONFIG_BEFS_FS is not set
# CONFIG_BFS_FS is not set
# CONFIG_EFS_FS is not set
# CONFIG_CRAMFS is not set
CONFIG_SQUASHFS=y
CONFIG_SQUASHFS_FILE_CACHE=y
# CONFIG_SQUASHFS_FILE_DIRECT is not set
CONFIG_SQUASHFS_DECOMP_SINGLE=y
# CONFIG_SQUASHFS_DECOMP_MULTI is not set
# CONFIG_SQUASHFS_DECOMP_MULTI_PERCPU is not set
CONFIG_SQUASHFS_XATTR=y
CONFIG_SQUASHFS_ZLIB=y
# CONFIG_SQUASHFS_LZ4 is not set
CONFIG_SQUASHFS_LZO=y
# CONFIG_SQUASHFS_XZ is not set
# CONFIG_SQUASHFS_ZSTD is not set
# CONFIG_SQUASHFS_4K_DEVBLK_SIZE is not set
# CONFIG_SQUASHFS_EMBEDDED is not set
CONFIG_SQUASHFS_FRAGMENT_CACHE_SIZE=3
# CONFIG_VXFS_FS is not set
# CONFIG_MINIX_FS is not set
# CONFIG_OMFS_FS is not set
# CONFIG_HPFS_FS is not set
# CONFIG_QNX4FS_FS is not set
# CONFIG_QNX6FS_FS is not set
# CONFIG_ROMFS_FS is not set
# CONFIG_PSTORE is not set
# CONFIG_SYSV_FS is not set
# CONFIG_UFS_FS is not set
CONFIG_NETWORK_FILESYSTEMS=y
CONFIG_NFS_FS=y
CONFIG_NFS_V2=y
CONFIG_NFS_V3=y
CONFIG_NFS_V3_ACL=y
CONFIG_NFS_V4=y
# CONFIG_NFS_SWAP is not set
CONFIG_NFS_V4_1=y
# CONFIG_NFS_V4_2 is not set
CONFIG_PNFS_FILE_LAYOUT=y
CONFIG_PNFS_BLOCK=y
CONFIG_PNFS_FLEXFILE_LAYOUT=y
CONFIG_NFS_V4_1_IMPLEMENTATION_ID_DOMAIN="kernel.org"
# CONFIG_NFS_V4_1_MIGRATION is not set
CONFIG_ROOT_NFS=y
CONFIG_NFS_FSCACHE=y
# CONFIG_NFS_USE_LEGACY_DNS is not set
CONFIG_NFS_USE_KERNEL_DNS=y
CONFIG_NFSD=y
CONFIG_NFSD_V2_ACL=y
CONFIG_NFSD_V3=y
CONFIG_NFSD_V3_ACL=y
CONFIG_NFSD_V4=y
CONFIG_NFSD_PNFS=y
CONFIG_NFSD_BLOCKLAYOUT=y
CONFIG_NFSD_SCSILAYOUT=y
CONFIG_NFSD_FLEXFILELAYOUT=y
# CONFIG_NFSD_V4_SECURITY_LABEL is not set
# CONFIG_NFSD_FAULT_INJECTION is not set
CONFIG_GRACE_PERIOD=y
CONFIG_LOCKD=y
CONFIG_LOCKD_V4=y
CONFIG_NFS_ACL_SUPPORT=y
CONFIG_NFS_COMMON=y
CONFIG_SUNRPC=y
CONFIG_SUNRPC_GSS=y
CONFIG_SUNRPC_BACKCHANNEL=y
CONFIG_RPCSEC_GSS_KRB5=y
# CONFIG_SUNRPC_DEBUG is not set
# CONFIG_CEPH_FS is not set
CONFIG_CIFS=y
CONFIG_CIFS_STATS=y
CONFIG_CIFS_STATS2=y
# CONFIG_CIFS_WEAK_PW_HASH is not set
# CONFIG_CIFS_UPCALL is not set
CONFIG_CIFS_XATTR=y
CONFIG_CIFS_POSIX=y
CONFIG_CIFS_ACL=y
CONFIG_CIFS_DEBUG=y
# CONFIG_CIFS_DEBUG2 is not set
# CONFIG_CIFS_DEBUG_DUMP_KEYS is not set
# CONFIG_CIFS_DFS_UPCALL is not set
# CONFIG_CIFS_SMB311 is not set
CONFIG_CIFS_FSCACHE=y
# CONFIG_CODA_FS is not set
# CONFIG_AFS_FS is not set
CONFIG_NLS=y
CONFIG_NLS_DEFAULT="utf8"
CONFIG_NLS_CODEPAGE_437=y
# CONFIG_NLS_CODEPAGE_737 is not set
# CONFIG_NLS_CODEPAGE_775 is not set
# CONFIG_NLS_CODEPAGE_850 is not set
# CONFIG_NLS_CODEPAGE_852 is not set
# CONFIG_NLS_CODEPAGE_855 is not set
# CONFIG_NLS_CODEPAGE_857 is not set
# CONFIG_NLS_CODEPAGE_860 is not set
# CONFIG_NLS_CODEPAGE_861 is not set
# CONFIG_NLS_CODEPAGE_862 is not set
# CONFIG_NLS_CODEPAGE_863 is not set
# CONFIG_NLS_CODEPAGE_864 is not set
# CONFIG_NLS_CODEPAGE_865 is not set
# CONFIG_NLS_CODEPAGE_866 is not set
# CONFIG_NLS_CODEPAGE_869 is not set
# CONFIG_NLS_CODEPAGE_936 is not set
# CONFIG_NLS_CODEPAGE_950 is not set
# CONFIG_NLS_CODEPAGE_932 is not set
# CONFIG_NLS_CODEPAGE_949 is not set
# CONFIG_NLS_CODEPAGE_874 is not set
# CONFIG_NLS_ISO8859_8 is not set
# CONFIG_NLS_CODEPAGE_1250 is not set
# CONFIG_NLS_CODEPAGE_1251 is not set
CONFIG_NLS_ASCII=y
CONFIG_NLS_ISO8859_1=y
# CONFIG_NLS_ISO8859_2 is not set
# CONFIG_NLS_ISO8859_3 is not set
# CONFIG_NLS_ISO8859_4 is not set
# CONFIG_NLS_ISO8859_5 is not set
# CONFIG_NLS_ISO8859_6 is not set
# CONFIG_NLS_ISO8859_7 is not set
# CONFIG_NLS_ISO8859_9 is not set
# CONFIG_NLS_ISO8859_13 is not set
# CONFIG_NLS_ISO8859_14 is not set
# CONFIG_NLS_ISO8859_15 is not set
# CONFIG_NLS_KOI8_R is not set
# CONFIG_NLS_KOI8_U is not set
# CONFIG_NLS_MAC_ROMAN is not set
# CONFIG_NLS_MAC_CELTIC is not set
# CONFIG_NLS_MAC_CENTEURO is not set
# CONFIG_NLS_MAC_CROATIAN is not set
# CONFIG_NLS_MAC_CYRILLIC is not set
# CONFIG_NLS_MAC_GAELIC is not set
# CONFIG_NLS_MAC_GREEK is not set
# CONFIG_NLS_MAC_ICELAND is not set
# CONFIG_NLS_MAC_INUIT is not set
# CONFIG_NLS_MAC_ROMANIAN is not set
# CONFIG_NLS_MAC_TURKISH is not set
CONFIG_NLS_UTF8=y
CONFIG_DLM=y
# CONFIG_DLM_DEBUG is not set

#
# Kernel hacking
#
CONFIG_TRACE_IRQFLAGS_SUPPORT=y

#
# printk and dmesg options
#
CONFIG_PRINTK_TIME=y
CONFIG_CONSOLE_LOGLEVEL_DEFAULT=7
CONFIG_MESSAGE_LOGLEVEL_DEFAULT=4
# CONFIG_BOOT_PRINTK_DELAY is not set
# CONFIG_DYNAMIC_DEBUG is not set

#
# Compile-time checks and compiler options
#
CONFIG_DEBUG_INFO=y
# CONFIG_DEBUG_INFO_REDUCED is not set
# CONFIG_DEBUG_INFO_SPLIT is not set
CONFIG_DEBUG_INFO_DWARF4=y
# CONFIG_GDB_SCRIPTS is not set
# CONFIG_ENABLE_WARN_DEPRECATED is not set
CONFIG_ENABLE_MUST_CHECK=y
CONFIG_FRAME_WARN=4096
# CONFIG_STRIP_ASM_SYMS is not set
# CONFIG_READABLE_ASM is not set
# CONFIG_UNUSED_SYMBOLS is not set
# CONFIG_PAGE_OWNER is not set
CONFIG_DEBUG_FS=y
# CONFIG_HEADERS_CHECK is not set
# CONFIG_DEBUG_SECTION_MISMATCH is not set
CONFIG_SECTION_MISMATCH_WARN_ONLY=y
CONFIG_STACK_VALIDATION=y
# CONFIG_DEBUG_FORCE_WEAK_PER_CPU is not set
CONFIG_MAGIC_SYSRQ=y
CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE=0x1
CONFIG_MAGIC_SYSRQ_SERIAL=y
CONFIG_DEBUG_KERNEL=y

#
# Memory Debugging
#
# CONFIG_PAGE_EXTENSION is not set
# CONFIG_DEBUG_PAGEALLOC is not set
# CONFIG_PAGE_POISONING is not set
# CONFIG_DEBUG_PAGE_REF is not set
# CONFIG_DEBUG_RODATA_TEST is not set
# CONFIG_DEBUG_OBJECTS is not set
# CONFIG_DEBUG_SLAB is not set
CONFIG_HAVE_DEBUG_KMEMLEAK=y
# CONFIG_DEBUG_KMEMLEAK is not set
CONFIG_DEBUG_STACK_USAGE=y
# CONFIG_DEBUG_VM is not set
CONFIG_ARCH_HAS_DEBUG_VIRTUAL=y
# CONFIG_DEBUG_VIRTUAL is not set
# CONFIG_DEBUG_MEMORY_INIT is not set
# CONFIG_DEBUG_PER_CPU_MAPS is not set
CONFIG_HAVE_DEBUG_STACKOVERFLOW=y
CONFIG_DEBUG_STACKOVERFLOW=y
CONFIG_HAVE_ARCH_KASAN=y
# CONFIG_KASAN is not set
CONFIG_ARCH_HAS_KCOV=y
# CONFIG_KCOV is not set
# CONFIG_DEBUG_SHIRQ is not set

#
# Debug Lockups and Hangs
#
CONFIG_LOCKUP_DETECTOR=y
CONFIG_SOFTLOCKUP_DETECTOR=y
# CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC is not set
CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC_VALUE=0
CONFIG_HARDLOCKUP_DETECTOR_PERF=y
CONFIG_HARDLOCKUP_CHECK_TIMESTAMP=y
CONFIG_HARDLOCKUP_DETECTOR=y
# CONFIG_BOOTPARAM_HARDLOCKUP_PANIC is not set
CONFIG_BOOTPARAM_HARDLOCKUP_PANIC_VALUE=0
CONFIG_DETECT_HUNG_TASK=y
CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=120
# CONFIG_BOOTPARAM_HUNG_TASK_PANIC is not set
CONFIG_BOOTPARAM_HUNG_TASK_PANIC_VALUE=0
# CONFIG_WQ_WATCHDOG is not set
# CONFIG_PANIC_ON_OOPS is not set
CONFIG_PANIC_ON_OOPS_VALUE=0
CONFIG_PANIC_TIMEOUT=0
CONFIG_SCHED_DEBUG=y
CONFIG_SCHED_INFO=y
CONFIG_SCHEDSTATS=y
CONFIG_SCHED_STACK_END_CHECK=y
# CONFIG_DEBUG_TIMEKEEPING is not set
# CONFIG_DEBUG_PREEMPT is not set

#
# Lock Debugging (spinlocks, mutexes, etc...)
#
CONFIG_LOCK_DEBUGGING_SUPPORT=y
# CONFIG_PROVE_LOCKING is not set
# CONFIG_LOCK_STAT is not set
# CONFIG_DEBUG_RT_MUTEXES is not set
CONFIG_DEBUG_SPINLOCK=y
CONFIG_DEBUG_MUTEXES=y
# CONFIG_DEBUG_WW_MUTEX_SLOWPATH is not set
CONFIG_DEBUG_RWSEMS=y
# CONFIG_DEBUG_LOCK_ALLOC is not set
CONFIG_DEBUG_ATOMIC_SLEEP=y
# CONFIG_DEBUG_LOCKING_API_SELFTESTS is not set
# CONFIG_LOCK_TORTURE_TEST is not set
# CONFIG_WW_MUTEX_SELFTEST is not set
CONFIG_TRACE_IRQFLAGS=y
CONFIG_STACKTRACE=y
# CONFIG_WARN_ALL_UNSEEDED_RANDOM is not set
# CONFIG_DEBUG_KOBJECT is not set
CONFIG_DEBUG_BUGVERBOSE=y
CONFIG_DEBUG_LIST=y
# CONFIG_DEBUG_PI_LIST is not set
# CONFIG_DEBUG_SG is not set
# CONFIG_DEBUG_NOTIFIERS is not set
# CONFIG_DEBUG_CREDENTIALS is not set

#
# RCU Debugging
#
# CONFIG_RCU_PERF_TEST is not set
# CONFIG_RCU_TORTURE_TEST is not set
CONFIG_RCU_CPU_STALL_TIMEOUT=21
# CONFIG_RCU_TRACE is not set
# CONFIG_RCU_EQS_DEBUG is not set
# CONFIG_DEBUG_WQ_FORCE_RR_CPU is not set
# CONFIG_DEBUG_BLOCK_EXT_DEVT is not set
# CONFIG_CPU_HOTPLUG_STATE_CONTROL is not set
# CONFIG_NOTIFIER_ERROR_INJECTION is not set
CONFIG_FAULT_INJECTION=y
# CONFIG_FAILSLAB is not set
# CONFIG_FAIL_PAGE_ALLOC is not set
CONFIG_FAIL_MAKE_REQUEST=y
# CONFIG_FAIL_IO_TIMEOUT is not set
# CONFIG_FAIL_FUTEX is not set
CONFIG_FAULT_INJECTION_DEBUG_FS=y
CONFIG_LATENCYTOP=y
CONFIG_USER_STACKTRACE_SUPPORT=y
CONFIG_NOP_TRACER=y
CONFIG_HAVE_FUNCTION_TRACER=y
CONFIG_HAVE_FUNCTION_GRAPH_TRACER=y
CONFIG_HAVE_DYNAMIC_FTRACE=y
CONFIG_HAVE_DYNAMIC_FTRACE_WITH_REGS=y
CONFIG_HAVE_FTRACE_MCOUNT_RECORD=y
CONFIG_HAVE_SYSCALL_TRACEPOINTS=y
CONFIG_HAVE_FENTRY=y
CONFIG_HAVE_C_RECORDMCOUNT=y
CONFIG_TRACE_CLOCK=y
CONFIG_RING_BUFFER=y
CONFIG_EVENT_TRACING=y
CONFIG_CONTEXT_SWITCH_TRACER=y
CONFIG_RING_BUFFER_ALLOW_SWAP=y
CONFIG_TRACING=y
CONFIG_GENERIC_TRACER=y
CONFIG_TRACING_SUPPORT=y
CONFIG_FTRACE=y
CONFIG_FUNCTION_TRACER=y
CONFIG_FUNCTION_GRAPH_TRACER=y
CONFIG_PREEMPTIRQ_EVENTS=y
# CONFIG_IRQSOFF_TRACER is not set
# CONFIG_PREEMPT_TRACER is not set
# CONFIG_SCHED_TRACER is not set
# CONFIG_HWLAT_TRACER is not set
# CONFIG_FTRACE_SYSCALLS is not set
# CONFIG_TRACER_SNAPSHOT is not set
CONFIG_BRANCH_PROFILE_NONE=y
# CONFIG_PROFILE_ANNOTATED_BRANCHES is not set
# CONFIG_PROFILE_ALL_BRANCHES is not set
CONFIG_STACK_TRACER=y
CONFIG_BLK_DEV_IO_TRACE=y
CONFIG_UPROBE_EVENTS=y
CONFIG_PROBE_EVENTS=y
CONFIG_DYNAMIC_FTRACE=y
CONFIG_DYNAMIC_FTRACE_WITH_REGS=y
# CONFIG_FUNCTION_PROFILER is not set
CONFIG_FTRACE_MCOUNT_RECORD=y
# CONFIG_FTRACE_STARTUP_TEST is not set
# CONFIG_MMIOTRACE is not set
# CONFIG_HIST_TRIGGERS is not set
# CONFIG_TRACEPOINT_BENCHMARK is not set
# CONFIG_RING_BUFFER_BENCHMARK is not set
# CONFIG_RING_BUFFER_STARTUP_TEST is not set
# CONFIG_TRACE_EVAL_MAP_FILE is not set
# CONFIG_PROVIDE_OHCI1394_DMA_INIT is not set
# CONFIG_DMA_API_DEBUG is not set
# CONFIG_RUNTIME_TESTING_MENU is not set
# CONFIG_MEMTEST is not set
# CONFIG_BUG_ON_DATA_CORRUPTION is not set
# CONFIG_SAMPLES is not set
CONFIG_HAVE_ARCH_KGDB=y
# CONFIG_KGDB is not set
CONFIG_ARCH_HAS_UBSAN_SANITIZE_ALL=y
# CONFIG_UBSAN is not set
CONFIG_ARCH_HAS_DEVMEM_IS_ALLOWED=y
# CONFIG_STRICT_DEVMEM is not set
CONFIG_EARLY_PRINTK_USB=y
CONFIG_X86_VERBOSE_BOOTUP=y
CONFIG_EARLY_PRINTK=y
CONFIG_EARLY_PRINTK_DBGP=y
# CONFIG_EARLY_PRINTK_EFI is not set
# CONFIG_EARLY_PRINTK_USB_XDBC is not set
# CONFIG_X86_PTDUMP is not set
# CONFIG_EFI_PGT_DUMP is not set
# CONFIG_DEBUG_WX is not set
CONFIG_DOUBLEFAULT=y
# CONFIG_DEBUG_TLBFLUSH is not set
# CONFIG_IOMMU_DEBUG is not set
CONFIG_HAVE_MMIOTRACE_SUPPORT=y
CONFIG_IO_DELAY_TYPE_0X80=0
CONFIG_IO_DELAY_TYPE_0XED=1
CONFIG_IO_DELAY_TYPE_UDELAY=2
CONFIG_IO_DELAY_TYPE_NONE=3
CONFIG_IO_DELAY_0X80=y
# CONFIG_IO_DELAY_0XED is not set
# CONFIG_IO_DELAY_UDELAY is not set
# CONFIG_IO_DELAY_NONE is not set
CONFIG_DEFAULT_IO_DELAY_TYPE=0
CONFIG_DEBUG_BOOT_PARAMS=y
# CONFIG_CPA_DEBUG is not set
CONFIG_OPTIMIZE_INLINING=y
# CONFIG_DEBUG_ENTRY is not set
# CONFIG_DEBUG_NMI_SELFTEST is not set
# CONFIG_X86_DEBUG_FPU is not set
# CONFIG_PUNIT_ATOM_DEBUG is not set
CONFIG_UNWINDER_ORC=y
# CONFIG_UNWINDER_FRAME_POINTER is not set
# CONFIG_UNWINDER_GUESS is not set

#
# Security options
#
CONFIG_KEYS=y
CONFIG_KEYS_COMPAT=y
# CONFIG_PERSISTENT_KEYRINGS is not set
# CONFIG_BIG_KEYS is not set
CONFIG_ENCRYPTED_KEYS=y
# CONFIG_KEY_DH_OPERATIONS is not set
# CONFIG_SECURITY_DMESG_RESTRICT is not set
CONFIG_SECURITY=y
CONFIG_SECURITY_WRITABLE_HOOKS=y
CONFIG_SECURITYFS=y
CONFIG_SECURITY_NETWORK=y
# CONFIG_PAGE_TABLE_ISOLATION is not set
CONFIG_SECURITY_PATH=y
CONFIG_LSM_MMAP_MIN_ADDR=65536
CONFIG_HAVE_HARDENED_USERCOPY_ALLOCATOR=y
# CONFIG_HARDENED_USERCOPY is not set
# CONFIG_FORTIFY_SOURCE is not set
# CONFIG_STATIC_USERMODEHELPER is not set
CONFIG_SECURITY_SELINUX=y
CONFIG_SECURITY_SELINUX_BOOTPARAM=y
CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE=1
CONFIG_SECURITY_SELINUX_DISABLE=y
CONFIG_SECURITY_SELINUX_DEVELOP=y
CONFIG_SECURITY_SELINUX_AVC_STATS=y
CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE=1
# CONFIG_SECURITY_SMACK is not set
# CONFIG_SECURITY_TOMOYO is not set
# CONFIG_SECURITY_APPARMOR is not set
# CONFIG_SECURITY_LOADPIN is not set
# CONFIG_SECURITY_YAMA is not set
# CONFIG_INTEGRITY is not set
# CONFIG_DEFAULT_SECURITY_SELINUX is not set
CONFIG_DEFAULT_SECURITY_DAC=y
CONFIG_DEFAULT_SECURITY=""
CONFIG_XOR_BLOCKS=y
CONFIG_ASYNC_CORE=y
CONFIG_ASYNC_MEMCPY=y
CONFIG_ASYNC_XOR=y
CONFIG_ASYNC_PQ=y
CONFIG_ASYNC_RAID6_RECOV=y
CONFIG_CRYPTO=y

#
# Crypto core or helper
#
CONFIG_CRYPTO_ALGAPI=y
CONFIG_CRYPTO_ALGAPI2=y
CONFIG_CRYPTO_AEAD=y
CONFIG_CRYPTO_AEAD2=y
CONFIG_CRYPTO_BLKCIPHER=y
CONFIG_CRYPTO_BLKCIPHER2=y
CONFIG_CRYPTO_HASH=y
CONFIG_CRYPTO_HASH2=y
CONFIG_CRYPTO_RNG=y
CONFIG_CRYPTO_RNG2=y
CONFIG_CRYPTO_RNG_DEFAULT=y
CONFIG_CRYPTO_AKCIPHER2=y
CONFIG_CRYPTO_KPP2=y
CONFIG_CRYPTO_ACOMP2=y
# CONFIG_CRYPTO_RSA is not set
# CONFIG_CRYPTO_DH is not set
# CONFIG_CRYPTO_ECDH is not set
CONFIG_CRYPTO_MANAGER=y
CONFIG_CRYPTO_MANAGER2=y
# CONFIG_CRYPTO_USER is not set
CONFIG_CRYPTO_MANAGER_DISABLE_TESTS=y
CONFIG_CRYPTO_GF128MUL=y
CONFIG_CRYPTO_NULL=y
CONFIG_CRYPTO_NULL2=y
# CONFIG_CRYPTO_PCRYPT is not set
CONFIG_CRYPTO_WORKQUEUE=y
# CONFIG_CRYPTO_CRYPTD is not set
# CONFIG_CRYPTO_MCRYPTD is not set
CONFIG_CRYPTO_AUTHENC=y
CONFIG_CRYPTO_ENGINE=y

#
# Authenticated Encryption with Associated Data
#
CONFIG_CRYPTO_CCM=y
# CONFIG_CRYPTO_GCM is not set
# CONFIG_CRYPTO_CHACHA20POLY1305 is not set
CONFIG_CRYPTO_SEQIV=y
CONFIG_CRYPTO_ECHAINIV=y

#
# Block modes
#
CONFIG_CRYPTO_CBC=y
# CONFIG_CRYPTO_CFB is not set
CONFIG_CRYPTO_CTR=y
CONFIG_CRYPTO_CTS=y
CONFIG_CRYPTO_ECB=y
# CONFIG_CRYPTO_LRW is not set
# CONFIG_CRYPTO_PCBC is not set
CONFIG_CRYPTO_XTS=y
# CONFIG_CRYPTO_KEYWRAP is not set

#
# Hash modes
#
CONFIG_CRYPTO_CMAC=y
CONFIG_CRYPTO_HMAC=y
# CONFIG_CRYPTO_XCBC is not set
# CONFIG_CRYPTO_VMAC is not set

#
# Digest
#
CONFIG_CRYPTO_CRC32C=y
CONFIG_CRYPTO_CRC32C_INTEL=y
CONFIG_CRYPTO_CRC32=y
CONFIG_CRYPTO_CRC32_PCLMUL=y
CONFIG_CRYPTO_CRCT10DIF=y
# CONFIG_CRYPTO_CRCT10DIF_PCLMUL is not set
# CONFIG_CRYPTO_GHASH is not set
# CONFIG_CRYPTO_POLY1305 is not set
# CONFIG_CRYPTO_POLY1305_X86_64 is not set
CONFIG_CRYPTO_MD4=y
CONFIG_CRYPTO_MD5=y
# CONFIG_CRYPTO_MICHAEL_MIC is not set
# CONFIG_CRYPTO_RMD128 is not set
# CONFIG_CRYPTO_RMD160 is not set
# CONFIG_CRYPTO_RMD256 is not set
# CONFIG_CRYPTO_RMD320 is not set
CONFIG_CRYPTO_SHA1=y
# CONFIG_CRYPTO_SHA1_SSSE3 is not set
# CONFIG_CRYPTO_SHA256_SSSE3 is not set
# CONFIG_CRYPTO_SHA512_SSSE3 is not set
# CONFIG_CRYPTO_SHA1_MB is not set
# CONFIG_CRYPTO_SHA256_MB is not set
# CONFIG_CRYPTO_SHA512_MB is not set
CONFIG_CRYPTO_SHA256=y
# CONFIG_CRYPTO_SHA512 is not set
# CONFIG_CRYPTO_SHA3 is not set
# CONFIG_CRYPTO_SM3 is not set
# CONFIG_CRYPTO_TGR192 is not set
# CONFIG_CRYPTO_WP512 is not set
# CONFIG_CRYPTO_GHASH_CLMUL_NI_INTEL is not set

#
# Ciphers
#
CONFIG_CRYPTO_AES=y
# CONFIG_CRYPTO_AES_TI is not set
# CONFIG_CRYPTO_AES_X86_64 is not set
# CONFIG_CRYPTO_AES_NI_INTEL is not set
# CONFIG_CRYPTO_ANUBIS is not set
CONFIG_CRYPTO_ARC4=y
# CONFIG_CRYPTO_BLOWFISH is not set
# CONFIG_CRYPTO_BLOWFISH_X86_64 is not set
# CONFIG_CRYPTO_CAMELLIA is not set
# CONFIG_CRYPTO_CAMELLIA_X86_64 is not set
# CONFIG_CRYPTO_CAMELLIA_AESNI_AVX_X86_64 is not set
# CONFIG_CRYPTO_CAMELLIA_AESNI_AVX2_X86_64 is not set
CONFIG_CRYPTO_CAST_COMMON=y
CONFIG_CRYPTO_CAST5=y
# CONFIG_CRYPTO_CAST5_AVX_X86_64 is not set
# CONFIG_CRYPTO_CAST6 is not set
# CONFIG_CRYPTO_CAST6_AVX_X86_64 is not set
CONFIG_CRYPTO_DES=y
# CONFIG_CRYPTO_DES3_EDE_X86_64 is not set
# CONFIG_CRYPTO_FCRYPT is not set
# CONFIG_CRYPTO_KHAZAD is not set
# CONFIG_CRYPTO_SALSA20 is not set
# CONFIG_CRYPTO_SALSA20_X86_64 is not set
# CONFIG_CRYPTO_CHACHA20 is not set
# CONFIG_CRYPTO_CHACHA20_X86_64 is not set
# CONFIG_CRYPTO_SEED is not set
# CONFIG_CRYPTO_SERPENT is not set
# CONFIG_CRYPTO_SERPENT_SSE2_X86_64 is not set
# CONFIG_CRYPTO_SERPENT_AVX_X86_64 is not set
# CONFIG_CRYPTO_SERPENT_AVX2_X86_64 is not set
# CONFIG_CRYPTO_SM4 is not set
# CONFIG_CRYPTO_SPECK is not set
# CONFIG_CRYPTO_TEA is not set
# CONFIG_CRYPTO_TWOFISH is not set
# CONFIG_CRYPTO_TWOFISH_X86_64 is not set
# CONFIG_CRYPTO_TWOFISH_X86_64_3WAY is not set
# CONFIG_CRYPTO_TWOFISH_AVX_X86_64 is not set

#
# Compression
#
# CONFIG_CRYPTO_DEFLATE is not set
CONFIG_CRYPTO_LZO=y
# CONFIG_CRYPTO_842 is not set
# CONFIG_CRYPTO_LZ4 is not set
# CONFIG_CRYPTO_LZ4HC is not set

#
# Random Number Generation
#
# CONFIG_CRYPTO_ANSI_CPRNG is not set
CONFIG_CRYPTO_DRBG_MENU=y
CONFIG_CRYPTO_DRBG_HMAC=y
# CONFIG_CRYPTO_DRBG_HASH is not set
# CONFIG_CRYPTO_DRBG_CTR is not set
CONFIG_CRYPTO_DRBG=y
CONFIG_CRYPTO_JITTERENTROPY=y
# CONFIG_CRYPTO_USER_API_HASH is not set
# CONFIG_CRYPTO_USER_API_SKCIPHER is not set
# CONFIG_CRYPTO_USER_API_RNG is not set
# CONFIG_CRYPTO_USER_API_AEAD is not set
CONFIG_CRYPTO_HW=y
# CONFIG_CRYPTO_DEV_PADLOCK is not set
# CONFIG_CRYPTO_DEV_CCP is not set
# CONFIG_CRYPTO_DEV_QAT_DH895xCC is not set
# CONFIG_CRYPTO_DEV_QAT_C3XXX is not set
# CONFIG_CRYPTO_DEV_QAT_C62X is not set
# CONFIG_CRYPTO_DEV_QAT_DH895xCCVF is not set
# CONFIG_CRYPTO_DEV_QAT_C3XXXVF is not set
# CONFIG_CRYPTO_DEV_QAT_C62XVF is not set
# CONFIG_CRYPTO_DEV_NITROX_CNN55XX is not set
CONFIG_CRYPTO_DEV_VIRTIO=y
# CONFIG_ASYMMETRIC_KEY_TYPE is not set

#
# Certificates for signature checking
#
# CONFIG_SYSTEM_BLACKLIST_KEYRING is not set
CONFIG_HAVE_KVM=y
CONFIG_HAVE_KVM_IRQCHIP=y
CONFIG_HAVE_KVM_IRQFD=y
CONFIG_HAVE_KVM_IRQ_ROUTING=y
CONFIG_HAVE_KVM_EVENTFD=y
CONFIG_KVM_MMIO=y
CONFIG_KVM_ASYNC_PF=y
CONFIG_HAVE_KVM_MSI=y
CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT=y
CONFIG_KVM_VFIO=y
CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT=y
CONFIG_KVM_COMPAT=y
CONFIG_HAVE_KVM_IRQ_BYPASS=y
CONFIG_VIRTUALIZATION=y
CONFIG_KVM=y
CONFIG_KVM_INTEL=y
# CONFIG_KVM_AMD is not set
# CONFIG_KVM_MMU_AUDIT is not set
CONFIG_VHOST_NET=y
CONFIG_VHOST=y
# CONFIG_VHOST_CROSS_ENDIAN_LEGACY is not set
CONFIG_BINARY_PRINTF=y

#
# Library routines
#
CONFIG_RAID6_PQ=y
CONFIG_BITREVERSE=y
CONFIG_RATIONAL=y
CONFIG_GENERIC_STRNCPY_FROM_USER=y
CONFIG_GENERIC_STRNLEN_USER=y
CONFIG_GENERIC_NET_UTILS=y
CONFIG_GENERIC_FIND_FIRST_BIT=y
CONFIG_GENERIC_PCI_IOMAP=y
CONFIG_GENERIC_IOMAP=y
CONFIG_ARCH_USE_CMPXCHG_LOCKREF=y
CONFIG_ARCH_HAS_FAST_MULTIPLIER=y
# CONFIG_CRC_CCITT is not set
CONFIG_CRC16=y
CONFIG_CRC_T10DIF=y
CONFIG_CRC_ITU_T=y
CONFIG_CRC32=y
# CONFIG_CRC32_SELFTEST is not set
CONFIG_CRC32_SLICEBY8=y
# CONFIG_CRC32_SLICEBY4 is not set
# CONFIG_CRC32_SARWATE is not set
# CONFIG_CRC32_BIT is not set
# CONFIG_CRC4 is not set
# CONFIG_CRC7 is not set
CONFIG_LIBCRC32C=y
# CONFIG_CRC8 is not set
CONFIG_XXHASH=y
# CONFIG_RANDOM32_SELFTEST is not set
CONFIG_ZLIB_INFLATE=y
CONFIG_ZLIB_DEFLATE=y
CONFIG_LZO_COMPRESS=y
CONFIG_LZO_DECOMPRESS=y
CONFIG_LZ4_DECOMPRESS=y
CONFIG_ZSTD_COMPRESS=y
CONFIG_ZSTD_DECOMPRESS=y
CONFIG_XZ_DEC=y
CONFIG_XZ_DEC_X86=y
CONFIG_XZ_DEC_POWERPC=y
CONFIG_XZ_DEC_IA64=y
CONFIG_XZ_DEC_ARM=y
CONFIG_XZ_DEC_ARMTHUMB=y
CONFIG_XZ_DEC_SPARC=y
CONFIG_XZ_DEC_BCJ=y
# CONFIG_XZ_DEC_TEST is not set
CONFIG_DECOMPRESS_GZIP=y
CONFIG_DECOMPRESS_BZIP2=y
CONFIG_DECOMPRESS_LZMA=y
CONFIG_DECOMPRESS_XZ=y
CONFIG_DECOMPRESS_LZO=y
CONFIG_DECOMPRESS_LZ4=y
CONFIG_GENERIC_ALLOCATOR=y
CONFIG_RADIX_TREE_MULTIORDER=y
CONFIG_ASSOCIATIVE_ARRAY=y
CONFIG_HAS_IOMEM=y
CONFIG_HAS_IOPORT_MAP=y
CONFIG_HAS_DMA=y
CONFIG_SGL_ALLOC=y
CONFIG_DMA_DIRECT_OPS=y
CONFIG_CHECK_SIGNATURE=y
CONFIG_CPUMASK_OFFSTACK=y
CONFIG_CPU_RMAP=y
CONFIG_DQL=y
CONFIG_GLOB=y
# CONFIG_GLOB_SELFTEST is not set
CONFIG_NLATTR=y
# CONFIG_CORDIC is not set
# CONFIG_DDR is not set
# CONFIG_IRQ_POLL is not set
CONFIG_OID_REGISTRY=y
CONFIG_UCS2_STRING=y
CONFIG_FONT_SUPPORT=y
# CONFIG_FONTS is not set
CONFIG_FONT_8x8=y
CONFIG_FONT_8x16=y
CONFIG_SG_POOL=y
CONFIG_ARCH_HAS_SG_CHAIN=y
CONFIG_ARCH_HAS_PMEM_API=y
CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE=y
CONFIG_SBITMAP=y
# CONFIG_STRING_SELFTEST is not set

Re: [PATCH v2 2/7] dax: change bdev_dax_supported() to support boolean returns

[Dan Williams]

[ adding KASAN devs...]

On Mon, Jun 4, 2018 at 4:40 PM, Dan Williams <dan.j.williams@intel.com> wrote:
> On Sun, Jun 3, 2018 at 6:48 PM, Dan Williams <dan.j.williams@intel.com> wrote:
>> On Sun, Jun 3, 2018 at 5:25 PM, Dave Chinner <david@fromorbit.com> wrote:
>>> On Mon, Jun 04, 2018 at 08:20:38AM +1000, Dave Chinner wrote:
>>>> On Thu, May 31, 2018 at 09:02:52PM -0700, Dan Williams wrote:
>>>> > On Thu, May 31, 2018 at 7:24 PM, Dave Chinner <david@fromorbit.com> wrote:
>>>> > > On Thu, May 31, 2018 at 06:57:33PM -0700, Dan Williams wrote:
>>>> > >> > FWIW, XFS+DAX used to just work on this setup (I hadn't even
>>>> > >> > installed ndctl until this morning!) but after changing the kernel
>>>> > >> > it no longer works. That would make it a regression, yes?
>>>>
>>>> [....]
>>>>
>>>> > >> I suspect your kernel does not have CONFIG_ZONE_DEVICE enabled which
>>>> > >> has the following dependencies:
>>>> > >>
>>>> > >>         depends on MEMORY_HOTPLUG
>>>> > >>         depends on MEMORY_HOTREMOVE
>>>> > >>         depends on SPARSEMEM_VMEMMAP
>>>> > >
>>>> > > Filesystem DAX now has a dependency on memory hotplug?
>>>>
>>>> [....]
>>>>
>>>> > > OK, works now I've found the magic config incantantions to turn
>>>> > > everything I now need on.
>>>>
>>>> By enabling these options, my test VM now has a ~30s pause in the
>>>> boot very soon after the nvdimm subsystem is initialised.
>>>>
>>>> [    1.523718] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
>>>> [    1.550353] 00:05: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
>>>> [    1.552175] Non-volatile memory driver v1.3
>>>> [    2.332045] tsc: Refined TSC clocksource calibration: 2199.909 MHz
>>>> [    2.333280] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x1fb5dcd4620, max_idle_ns: 440795264143 ns
>>>> [   37.217453] brd: module loaded
>>>> [   37.225423] loop: module loaded
>>>> [   37.228441] virtio_blk virtio2: [vda] 10485760 512-byte logical blocks (5.37 GB/5.00 GiB)
>>>> [   37.245418] virtio_blk virtio3: [vdb] 146800640 512-byte logical blocks (75.2 GB/70.0 GiB)
>>>> [   37.255794] virtio_blk virtio4: [vdc] 1073741824000 512-byte logical blocks (550 TB/500 TiB)
>>>> [   37.265403] nd_pmem namespace1.0: unable to guarantee persistence of writes
>>>> [   37.265618] nd_pmem namespace0.0: unable to guarantee persistence of writes
>>>>
>>>> The system does not appear to be consuming CPU, but it is blocking
>>>> NMIs so I can't get a CPU trace. For a VM that I rely on booting in
>>>> a few seconds because I reboot it tens of times a day, this is a
>>>> problem....
>>>
>>> And when I turn on KASAN, the kernel fails to boot to a login prompt
>>> because:
>>
>> What's your qemu and kernel command line? I'll take look at this first
>> thing tomorrow.
>
> I was able to reproduce this crash by just turning on KASAN...
> investigating. It would still help to have your config for our own
> regression testing purposes it makes sense for us to prioritize
> "Dave's test config", similar to the priority of not breaking Linus'
> laptop.

I believe this is a bug in KASAN, or a bug in devm_memremap_pages(),
depends on your point of view. At the very least it is a mismatch of
assumptions. KASAN learns of hot added memory via the memory hotplug
notifier. However, the devm_memremap_pages() implementation is
intentionally limited to the "first half" of the memory hotplug
procedure. I.e. it does just enough to setup the linear map for
pfn_to_page() and initialize the "struct page" memmap, but then stops
short of onlining the pages. This is why we are getting a NULL ptr
deref and not a KASAN report, because KASAN has no shadow area setup
for the linearly mapped pmem range.

In terms of solving it we could refactor kasan_mem_notifier() so that
devm_memremap_pages() can call it outside of the notifier... I'll give
this a shot.

[PATCH v2 3/7] dm: fix test for DAX device support

[Ross Zwisler]

Currently device_supports_dax() just checks to see if the QUEUE_FLAG_DAX
flag is set on the device's request queue to decide whether or not the
device supports filesystem DAX.  This is insufficient because there are
devices like PMEM namespaces in raw mode which have QUEUE_FLAG_DAX set but
which don't actually support DAX.

This means that you could create a dm-linear device, for example, where the
first part of the dm-linear device was a PMEM namespace in fsdax mode and
the second part was a PMEM namespace in raw mode.  Both DM and the
filesystem you put on that dm-linear device would think the whole device
supports DAX, which would lead to bad behavior once your raw PMEM namespace
part using DAX needed struct page for something.

Fix this by using bdev_dax_supported() like filesystems do at mount time.
This checks for raw mode and also performs other tests like checking to
make sure the dax_direct_access() path works.

Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Fixes: commit 545ed20e6df6 ("dm: add infrastructure for DAX support")
---
 drivers/md/dm-table.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 0589a4da12bb..5bb994b012ca 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -885,9 +885,7 @@ EXPORT_SYMBOL_GPL(dm_table_set_type);
 static int device_supports_dax(struct dm_target *ti, struct dm_dev *dev,
 			       sector_t start, sector_t len, void *data)
 {
-	struct request_queue *q = bdev_get_queue(dev->bdev);
-
-	return q && blk_queue_dax(q);
+	return bdev_dax_supported(dev->bdev, PAGE_SIZE);
 }
 
 static bool dm_table_supports_dax(struct dm_table *t)
-- 
2.14.3

Re: [PATCH v2 3/7] dm: fix test for DAX device support

[Mike Snitzer]

On Tue, May 29 2018 at  3:51P -0400,
Ross Zwisler <ross.zwisler@linux.intel.com> wrote:

> Currently device_supports_dax() just checks to see if the QUEUE_FLAG_DAX
> flag is set on the device's request queue to decide whether or not the
> device supports filesystem DAX.  This is insufficient because there are
> devices like PMEM namespaces in raw mode which have QUEUE_FLAG_DAX set but
> which don't actually support DAX.

Isn't that a PMEM bug then?

What is the point of setting QUEUE_FLAG_DAX if it cannot be trusted?
 
> This means that you could create a dm-linear device, for example, where the
> first part of the dm-linear device was a PMEM namespace in fsdax mode and
> the second part was a PMEM namespace in raw mode.  Both DM and the
> filesystem you put on that dm-linear device would think the whole device
> supports DAX, which would lead to bad behavior once your raw PMEM namespace
> part using DAX needed struct page for something.

The PMEM namespace in raw mode shouldn't be setting QUEUE_FLAG_DAX, if
it didn't then the stacked-up linear DM wouldn't 

> Fix this by using bdev_dax_supported() like filesystems do at mount time.
> This checks for raw mode and also performs other tests like checking to
> make sure the dax_direct_access() path works.

Sorry "This" does those things where?

> 
> Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
> Fixes: commit 545ed20e6df6 ("dm: add infrastructure for DAX support")
> ---
>  drivers/md/dm-table.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
> index 0589a4da12bb..5bb994b012ca 100644
> --- a/drivers/md/dm-table.c
> +++ b/drivers/md/dm-table.c
> @@ -885,9 +885,7 @@ EXPORT_SYMBOL_GPL(dm_table_set_type);
>  static int device_supports_dax(struct dm_target *ti, struct dm_dev *dev,
>  			       sector_t start, sector_t len, void *data)
>  {
> -	struct request_queue *q = bdev_get_queue(dev->bdev);
> -
> -	return q && blk_queue_dax(q);
> +	return bdev_dax_supported(dev->bdev, PAGE_SIZE);
>  }
>  
>  static bool dm_table_supports_dax(struct dm_table *t)
> -- 
> 2.14.3
> 

Re: [PATCH v2 3/7] dm: fix test for DAX device support

[Mike Snitzer]

On Fri, Jun 01 2018 at  4:19P -0400,
Mike Snitzer <snitzer@redhat.com> wrote:

> On Tue, May 29 2018 at  3:51P -0400,
> Ross Zwisler <ross.zwisler@linux.intel.com> wrote:
> 
> > Currently device_supports_dax() just checks to see if the QUEUE_FLAG_DAX
> > flag is set on the device's request queue to decide whether or not the
> > device supports filesystem DAX.  This is insufficient because there are
> > devices like PMEM namespaces in raw mode which have QUEUE_FLAG_DAX set but
> > which don't actually support DAX.
> 
> Isn't that a PMEM bug then?
> 
> What is the point of setting QUEUE_FLAG_DAX if it cannot be trusted?
>  
> > This means that you could create a dm-linear device, for example, where the
> > first part of the dm-linear device was a PMEM namespace in fsdax mode and
> > the second part was a PMEM namespace in raw mode.  Both DM and the
> > filesystem you put on that dm-linear device would think the whole device
> > supports DAX, which would lead to bad behavior once your raw PMEM namespace
> > part using DAX needed struct page for something.
> 
> The PMEM namespace in raw mode shouldn't be setting QUEUE_FLAG_DAX, if
> it didn't then the stacked-up linear DM wouldn't 
> 
> > Fix this by using bdev_dax_supported() like filesystems do at mount time.
> > This checks for raw mode and also performs other tests like checking to
> > make sure the dax_direct_access() path works.
> 
> Sorry "This" does those things where?

I see you meant bdev_dax_supported() does these additional checks.

My previous question stands though.  Why is QUEUE_FLAG_DAX getting set
if the device hasn't already passed these checks?  Shouldn't setting
QUEUE_FLAG_DAX on request_queue depend on bdev_dax_supported() passing?

But looking at the drivers that do set QUEUE_FLAG_DAX: they
don't have the bdev readily available.  Anyway, just strikes me as
bizarre that a driver can set QUEUE_FLAG_DAX without having to have
ensured bdev_dax_supported() passes (even if not programatically, but
that the developer has verified the hooks, et al exist).

But I'll give up on this line of questioning..

My dilemma now is: how do I take these changes without first rebasing
linux-dm.git ontop of Darrick's xfs tree?

I probably should've reviewed faster and been the one to take the entire
set (with appropriate acks obviously).

Re: [PATCH v2 3/7] dm: fix test for DAX device support

[Ross Zwisler]

On Fri, Jun 01, 2018 at 04:46:04PM -0400, Mike Snitzer wrote:
> On Fri, Jun 01 2018 at  4:19P -0400,
> Mike Snitzer <snitzer@redhat.com> wrote:
> 
> > On Tue, May 29 2018 at  3:51P -0400,
> > Ross Zwisler <ross.zwisler@linux.intel.com> wrote:
> > 
> > > Currently device_supports_dax() just checks to see if the QUEUE_FLAG_DAX
> > > flag is set on the device's request queue to decide whether or not the
> > > device supports filesystem DAX.  This is insufficient because there are
> > > devices like PMEM namespaces in raw mode which have QUEUE_FLAG_DAX set but
> > > which don't actually support DAX.
> > 
> > Isn't that a PMEM bug then?
> > 
> > What is the point of setting QUEUE_FLAG_DAX if it cannot be trusted?

Yup, that seems like a bug.

> > > This means that you could create a dm-linear device, for example, where the
> > > first part of the dm-linear device was a PMEM namespace in fsdax mode and
> > > the second part was a PMEM namespace in raw mode.  Both DM and the
> > > filesystem you put on that dm-linear device would think the whole device
> > > supports DAX, which would lead to bad behavior once your raw PMEM namespace
> > > part using DAX needed struct page for something.
> > 
> > The PMEM namespace in raw mode shouldn't be setting QUEUE_FLAG_DAX, if
> > it didn't then the stacked-up linear DM wouldn't 
> > 
> > > Fix this by using bdev_dax_supported() like filesystems do at mount time.
> > > This checks for raw mode and also performs other tests like checking to
> > > make sure the dax_direct_access() path works.
> > 
> > Sorry "This" does those things where?
> 
> I see you meant bdev_dax_supported() does these additional checks.
> 
> My previous question stands though.  Why is QUEUE_FLAG_DAX getting set
> if the device hasn't already passed these checks?  Shouldn't setting
> QUEUE_FLAG_DAX on request_queue depend on bdev_dax_supported() passing?
> 
> But looking at the drivers that do set QUEUE_FLAG_DAX: they
> don't have the bdev readily available.  Anyway, just strikes me as
> bizarre that a driver can set QUEUE_FLAG_DAX without having to have
> ensured bdev_dax_supported() passes (even if not programatically, but
> that the developer has verified the hooks, et al exist).

I agree that it's a bug that QUEUE_FLAG_DAX is set for raw mode namespaces,
thanks for pointing that out.  I will fix that, but I still think that DM
should be using bdev_dax_supported() like the filesystems do.  Even beyond the
raw mode / fsdax mode thing, this does additional checks that are useful. So,
I think these DM patches are still correct.

> But I'll give up on this line of questioning..
> 
> My dilemma now is: how do I take these changes without first rebasing
> linux-dm.git ontop of Darrick's xfs tree?
> 
> I probably should've reviewed faster and been the one to take the entire
> set (with appropriate acks obviously).

Re: [PATCH v2 3/7] dm: fix test for DAX device support

[Dan Williams]

On Fri, Jun 1, 2018 at 1:46 PM, Mike Snitzer <snitzer@redhat.com> wrote:
> On Fri, Jun 01 2018 at  4:19P -0400,
> Mike Snitzer <snitzer@redhat.com> wrote:
>
>> On Tue, May 29 2018 at  3:51P -0400,
>> Ross Zwisler <ross.zwisler@linux.intel.com> wrote:
>>
>> > Currently device_supports_dax() just checks to see if the QUEUE_FLAG_DAX
>> > flag is set on the device's request queue to decide whether or not the
>> > device supports filesystem DAX.  This is insufficient because there are
>> > devices like PMEM namespaces in raw mode which have QUEUE_FLAG_DAX set but
>> > which don't actually support DAX.
>>
>> Isn't that a PMEM bug then?
>>
>> What is the point of setting QUEUE_FLAG_DAX if it cannot be trusted?
>>
>> > This means that you could create a dm-linear device, for example, where the
>> > first part of the dm-linear device was a PMEM namespace in fsdax mode and
>> > the second part was a PMEM namespace in raw mode.  Both DM and the
>> > filesystem you put on that dm-linear device would think the whole device
>> > supports DAX, which would lead to bad behavior once your raw PMEM namespace
>> > part using DAX needed struct page for something.
>>
>> The PMEM namespace in raw mode shouldn't be setting QUEUE_FLAG_DAX, if
>> it didn't then the stacked-up linear DM wouldn't
>>
>> > Fix this by using bdev_dax_supported() like filesystems do at mount time.
>> > This checks for raw mode and also performs other tests like checking to
>> > make sure the dax_direct_access() path works.
>>
>> Sorry "This" does those things where?
>
> I see you meant bdev_dax_supported() does these additional checks.
>
> My previous question stands though.  Why is QUEUE_FLAG_DAX getting set
> if the device hasn't already passed these checks?  Shouldn't setting
> QUEUE_FLAG_DAX on request_queue depend on bdev_dax_supported() passing?
>
> But looking at the drivers that do set QUEUE_FLAG_DAX: they
> don't have the bdev readily available.  Anyway, just strikes me as
> bizarre that a driver can set QUEUE_FLAG_DAX without having to have
> ensured bdev_dax_supported() passes (even if not programatically, but
> that the developer has verified the hooks, et al exist).
>
> But I'll give up on this line of questioning..
>
> My dilemma now is: how do I take these changes without first rebasing
> linux-dm.git ontop of Darrick's xfs tree?
>
> I probably should've reviewed faster and been the one to take the entire
> set (with appropriate acks obviously).

I'd say just make a topic branch on top of xfs and merge it... with
Darrick's permission of course. It might also mean you should wait for
the xfs pull request to go to Linus first during the window.

[PATCH v2 4/7] dm: prevent DAX mounts if not supported

[Ross Zwisler]

Currently the code in dm_dax_direct_access() only checks whether the target
type has a direct_access() operation defined, not whether the underlying
block devices all support DAX.  This latter property can be seen by looking
at whether we set the QUEUE_FLAG_DAX request queue flag when creating the
DM device.

This is problematic if we have, for example, a dm-linear device made up of
a PMEM namespace in fsdax mode followed by a ramdisk from BRD.
QUEUE_FLAG_DAX won't be set on the dm-linear device's request queue, but
we have a working direct_access() entry point and the first member of the
dm-linear set *does* support DAX.

This allows the user to create a filesystem on the dm-linear device, and
then mount it with DAX.  The filesystem's bdev_dax_supported() test will
pass because it'll operate on the first member of the dm-linear device,
which happens to be a fsdax PMEM namespace.

All DAX I/O will then fail to that dm-linear device because the lack of
QUEUE_FLAG_DAX prevents fs_dax_get_by_bdev() from working.  This means that
the struct dax_device isn't ever set in the filesystem, so
dax_direct_access() will always return -EOPNOTSUPP.

By failing out of dm_dax_direct_access() if QUEUE_FLAG_DAX isn't set we let
the filesystem know we don't support DAX at mount time.  The filesystem
will then silently fall back and remove the dax mount option, causing it to
work properly.

Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Fixes: commit 545ed20e6df6 ("dm: add infrastructure for DAX support")
---
 drivers/md/dm.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 0a7b0107ca78..9728433362d1 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1050,14 +1050,13 @@ static long dm_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
 
 	if (!ti)
 		goto out;
-	if (!ti->type->direct_access)
+	if (!blk_queue_dax(md->queue))
 		goto out;
 	len = max_io_len(sector, ti) / PAGE_SECTORS;
 	if (len < 1)
 		goto out;
 	nr_pages = min(len, nr_pages);
-	if (ti->type->direct_access)
-		ret = ti->type->direct_access(ti, pgoff, nr_pages, kaddr, pfn);
+	ret = ti->type->direct_access(ti, pgoff, nr_pages, kaddr, pfn);
 
  out:
 	dm_put_live_table(md, srcu_idx);
-- 
2.14.3

Re: [PATCH v2 4/7] dm: prevent DAX mounts if not supported

[Mike Snitzer]

On Tue, May 29 2018 at  3:51pm -0400,
Ross Zwisler <ross.zwisler@linux.intel.com> wrote:

> Currently the code in dm_dax_direct_access() only checks whether the target
> type has a direct_access() operation defined, not whether the underlying
> block devices all support DAX.  This latter property can be seen by looking
> at whether we set the QUEUE_FLAG_DAX request queue flag when creating the
> DM device.

Wait... I thought DAX support was all or nothing?

> This is problematic if we have, for example, a dm-linear device made up of
> a PMEM namespace in fsdax mode followed by a ramdisk from BRD.
> QUEUE_FLAG_DAX won't be set on the dm-linear device's request queue, but
> we have a working direct_access() entry point and the first member of the
> dm-linear set *does* support DAX.

If you don't have a uniformly capable device then it is very dangerous
to advertise that the entire device has a certain capability.  That
completely bit me in the past with discard (because for every IO I
wasn't then checking if the destination device supported discards).

It is all well and good that you're adding that check here.  But what I
don't like is how you're saying QUEUE_FLAG_DAX implies direct_access()
operation exists.. yet for raw PMEM namespaces we just discussed how
that is a lie.

SO this type of change showcases how the QUEUE_FLAG_DAX doesn't _really_
imply direct_access() exists.

> This allows the user to create a filesystem on the dm-linear device, and
> then mount it with DAX.  The filesystem's bdev_dax_supported() test will
> pass because it'll operate on the first member of the dm-linear device,
> which happens to be a fsdax PMEM namespace.
> 
> All DAX I/O will then fail to that dm-linear device because the lack of
> QUEUE_FLAG_DAX prevents fs_dax_get_by_bdev() from working.  This means that
> the struct dax_device isn't ever set in the filesystem, so
> dax_direct_access() will always return -EOPNOTSUPP.

Now you've lost me... these past 2 paragraphs.  Why can a user mount it
is DAX mode?  Because bdev_dax_supported() only accesses the first
portion (which happens to have DAX capabilities?)

Isn't this exactly why you should be checking for QUEUE_FLAG_DAX in the
caller (bdev_dax_supported)?  Why not use bdev_get_queue() and verify
QUEUE_FLAG_DAX is set in there?

> By failing out of dm_dax_direct_access() if QUEUE_FLAG_DAX isn't set we let
> the filesystem know we don't support DAX at mount time.  The filesystem
> will then silently fall back and remove the dax mount option, causing it to
> work properly.

This shouldn't be needed.  Again, QUEUE_FLAG_DAX wasn't set.. so don't
allow code to falsely try operations that should've been gated by the
fact it wasn't set.

SO Nack on this patch.. until/unless I'm corrected ;)

Thanks,
Mike


> Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
> Fixes: commit 545ed20e6df6 ("dm: add infrastructure for DAX support")
> ---
>  drivers/md/dm.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/md/dm.c b/drivers/md/dm.c
> index 0a7b0107ca78..9728433362d1 100644
> --- a/drivers/md/dm.c
> +++ b/drivers/md/dm.c
> @@ -1050,14 +1050,13 @@ static long dm_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
>  
>  	if (!ti)
>  		goto out;
> -	if (!ti->type->direct_access)
> +	if (!blk_queue_dax(md->queue))
>  		goto out;
>  	len = max_io_len(sector, ti) / PAGE_SECTORS;
>  	if (len < 1)
>  		goto out;
>  	nr_pages = min(len, nr_pages);
> -	if (ti->type->direct_access)
> -		ret = ti->type->direct_access(ti, pgoff, nr_pages, kaddr, pfn);
> +	ret = ti->type->direct_access(ti, pgoff, nr_pages, kaddr, pfn);
>  
>   out:
>  	dm_put_live_table(md, srcu_idx);
> -- 
> 2.14.3
> 

Re: [PATCH v2 4/7] dm: prevent DAX mounts if not supported

[Ross Zwisler]

On Fri, Jun 01, 2018 at 05:55:13PM -0400, Mike Snitzer wrote:
> On Tue, May 29 2018 at  3:51pm -0400,
> Ross Zwisler <ross.zwisler@linux.intel.com> wrote:
> 
> > Currently the code in dm_dax_direct_access() only checks whether the target
> > type has a direct_access() operation defined, not whether the underlying
> > block devices all support DAX.  This latter property can be seen by looking
> > at whether we set the QUEUE_FLAG_DAX request queue flag when creating the
> > DM device.
> 
> Wait... I thought DAX support was all or nothing?

Right, it is, and that's what I'm trying to capture.  The point of this series
is to make sure that we don't use DAX thru DM if one of the DM members doesn't
support DAX.

This is a bit tricky, though, because as you've pointed out there are a lot of
elements that go into a block device actually supporting DAX.  

First, the block device has to have a direct_access() operation defined in its
struct dax_operations table.  This is a static definition in the drivers,
though, so it's necessary but not sufficient.  For example, the PMEM driver
always defines a direct_access() operation, but depending on the mode of the
namespace (raw, fsdax or sector) it may or may not support DAX.

The next step is that a driver needs to say that he block queue supports
QUEUE_FLAG_DAX.  This again is necessary but not sufficient.  The PMEM driver
currently sets this for all namespace modes, but I agree that this should be
restricted to modes that support DAX.  Even once we do that, though, for the
block driver this isn't fully sufficient.  We'd really like users to call
bdev_dax_supported() so it can run some additional tests to make sure that DAX
will work.

So, the real test that filesystems rely on is bdev_dax_suppported().

The trick is that with DM we need to verify each block device via
bdev_dax_supported() just like a filesystem would, and then have some way of
communicating the result of all those checks to the filesystem which is
eventually mounted on the DM device.  At DAX mount time the filesystem will
call bdev_dax_supported() on the DM device, but it'll really only check the
first device.  

So, the strategy is to have DM manually check each member device via
bdev_dax_supported() then if they all pass set QUEUE_FLAG_DAX.  This then
becomes our one source of truth on whether or not a DM device supports DAX.
When the filesystem mounts with DAX support it'll also run
bdev_dax_supported(), but if we have QUEUE_FLAG_DAX set on the DM device, we
know that this check will pass.

> > This is problematic if we have, for example, a dm-linear device made up of
> > a PMEM namespace in fsdax mode followed by a ramdisk from BRD.
> > QUEUE_FLAG_DAX won't be set on the dm-linear device's request queue, but
> > we have a working direct_access() entry point and the first member of the
> > dm-linear set *does* support DAX.
> 
> If you don't have a uniformly capable device then it is very dangerous
> to advertise that the entire device has a certain capability.  That
> completely bit me in the past with discard (because for every IO I
> wasn't then checking if the destination device supported discards).
>
> It is all well and good that you're adding that check here.  But what I
> don't like is how you're saying QUEUE_FLAG_DAX implies direct_access()
> operation exists.. yet for raw PMEM namespaces we just discussed how
> that is a lie.

QUEUE_FLAG_DAX does imply that direct_access() exits.  However, as discussed
above for a given bdev we really do need to check bdev_dax_supported().

> SO this type of change showcases how the QUEUE_FLAG_DAX doesn't _really_
> imply direct_access() exists.
> 
> > This allows the user to create a filesystem on the dm-linear device, and
> > then mount it with DAX.  The filesystem's bdev_dax_supported() test will
> > pass because it'll operate on the first member of the dm-linear device,
> > which happens to be a fsdax PMEM namespace.
> > 
> > All DAX I/O will then fail to that dm-linear device because the lack of
> > QUEUE_FLAG_DAX prevents fs_dax_get_by_bdev() from working.  This means that
> > the struct dax_device isn't ever set in the filesystem, so
> > dax_direct_access() will always return -EOPNOTSUPP.
> 
> Now you've lost me... these past 2 paragraphs.  Why can a user mount it
> is DAX mode?  Because bdev_dax_supported() only accesses the first
> portion (which happens to have DAX capabilities?)

Right.  bdev_dax_supported() runs all of its checks, and because they are
running against the first block device in the dm set, they all pass.  But the
overall DM device does not actually support DAX.

> Isn't this exactly why you should be checking for QUEUE_FLAG_DAX in the
> caller (bdev_dax_supported)?  Why not use bdev_get_queue() and verify
> QUEUE_FLAG_DAX is set in there?

I'll look into that for the next revision, thanks.

> > By failing out of dm_dax_direct_access() if QUEUE_FLAG_DAX isn't set we let
> > the filesystem know we don't support DAX at mount time.  The filesystem
> > will then silently fall back and remove the dax mount option, causing it to
> > work properly.
> 
> This shouldn't be needed.  Again, QUEUE_FLAG_DAX wasn't set.. so don't
> allow code to falsely try operations that should've been gated by the
> fact it wasn't set.

Right, the goal is to make QUEUE_FLAG_DAX our one source of truth for whether
DM devices support DAX, and not have it half defined by that and half by the
DM_TYPE_DAX_BIO_BASED.

Re: [PATCH v2 4/7] dm: prevent DAX mounts if not supported

[Mike Snitzer]

On Mon, Jun 04 2018 at  7:15pm -0400,
Ross Zwisler <ross.zwisler@linux.intel.com> wrote:

> On Fri, Jun 01, 2018 at 05:55:13PM -0400, Mike Snitzer wrote:
> > On Tue, May 29 2018 at  3:51pm -0400,
> > Ross Zwisler <ross.zwisler@linux.intel.com> wrote:
> > 
> > > Currently the code in dm_dax_direct_access() only checks whether the target
> > > type has a direct_access() operation defined, not whether the underlying
> > > block devices all support DAX.  This latter property can be seen by looking
> > > at whether we set the QUEUE_FLAG_DAX request queue flag when creating the
> > > DM device.
> > 
> > Wait... I thought DAX support was all or nothing?
> 
> Right, it is, and that's what I'm trying to capture.  The point of this series
> is to make sure that we don't use DAX thru DM if one of the DM members doesn't
> support DAX.
> 
> This is a bit tricky, though, because as you've pointed out there are a lot of
> elements that go into a block device actually supporting DAX.  
> 
> First, the block device has to have a direct_access() operation defined in its
> struct dax_operations table.  This is a static definition in the drivers,
> though, so it's necessary but not sufficient.  For example, the PMEM driver
> always defines a direct_access() operation, but depending on the mode of the
> namespace (raw, fsdax or sector) it may or may not support DAX.
> 
> The next step is that a driver needs to say that he block queue supports
> QUEUE_FLAG_DAX.  This again is necessary but not sufficient.  The PMEM driver
> currently sets this for all namespace modes, but I agree that this should be
> restricted to modes that support DAX.  Even once we do that, though, for the
> block driver this isn't fully sufficient.  We'd really like users to call
> bdev_dax_supported() so it can run some additional tests to make sure that DAX
> will work.
> 
> So, the real test that filesystems rely on is bdev_dax_suppported().
> 
> The trick is that with DM we need to verify each block device via
> bdev_dax_supported() just like a filesystem would, and then have some way of
> communicating the result of all those checks to the filesystem which is
> eventually mounted on the DM device.  At DAX mount time the filesystem will
> call bdev_dax_supported() on the DM device, but it'll really only check the
> first device.  
> 
> So, the strategy is to have DM manually check each member device via
> bdev_dax_supported() then if they all pass set QUEUE_FLAG_DAX.  This then
> becomes our one source of truth on whether or not a DM device supports DAX.
> When the filesystem mounts with DAX support it'll also run
> bdev_dax_supported(), but if we have QUEUE_FLAG_DAX set on the DM device, we
> know that this check will pass.
> 
> > > This is problematic if we have, for example, a dm-linear device made up of
> > > a PMEM namespace in fsdax mode followed by a ramdisk from BRD.
> > > QUEUE_FLAG_DAX won't be set on the dm-linear device's request queue, but
> > > we have a working direct_access() entry point and the first member of the
> > > dm-linear set *does* support DAX.
> > 
> > If you don't have a uniformly capable device then it is very dangerous
> > to advertise that the entire device has a certain capability.  That
> > completely bit me in the past with discard (because for every IO I
> > wasn't then checking if the destination device supported discards).
> >
> > It is all well and good that you're adding that check here.  But what I
> > don't like is how you're saying QUEUE_FLAG_DAX implies direct_access()
> > operation exists.. yet for raw PMEM namespaces we just discussed how
> > that is a lie.
> 
> QUEUE_FLAG_DAX does imply that direct_access() exits.  However, as discussed
> above for a given bdev we really do need to check bdev_dax_supported().
> 
> > SO this type of change showcases how the QUEUE_FLAG_DAX doesn't _really_
> > imply direct_access() exists.
> > 
> > > This allows the user to create a filesystem on the dm-linear device, and
> > > then mount it with DAX.  The filesystem's bdev_dax_supported() test will
> > > pass because it'll operate on the first member of the dm-linear device,
> > > which happens to be a fsdax PMEM namespace.
> > > 
> > > All DAX I/O will then fail to that dm-linear device because the lack of
> > > QUEUE_FLAG_DAX prevents fs_dax_get_by_bdev() from working.  This means that
> > > the struct dax_device isn't ever set in the filesystem, so
> > > dax_direct_access() will always return -EOPNOTSUPP.
> > 
> > Now you've lost me... these past 2 paragraphs.  Why can a user mount it
> > is DAX mode?  Because bdev_dax_supported() only accesses the first
> > portion (which happens to have DAX capabilities?)
> 
> Right.  bdev_dax_supported() runs all of its checks, and because they are
> running against the first block device in the dm set, they all pass.  But the
> overall DM device does not actually support DAX.
> 
> > Isn't this exactly why you should be checking for QUEUE_FLAG_DAX in the
> > caller (bdev_dax_supported)?  Why not use bdev_get_queue() and verify
> > QUEUE_FLAG_DAX is set in there?
> 
> I'll look into that for the next revision, thanks.

Have you made any progress on a new revision?

> > > By failing out of dm_dax_direct_access() if QUEUE_FLAG_DAX isn't set we let
> > > the filesystem know we don't support DAX at mount time.  The filesystem
> > > will then silently fall back and remove the dax mount option, causing it to
> > > work properly.
> > 
> > This shouldn't be needed.  Again, QUEUE_FLAG_DAX wasn't set.. so don't
> > allow code to falsely try operations that should've been gated by the
> > fact it wasn't set.
> 
> Right, the goal is to make QUEUE_FLAG_DAX our one source of truth for whether
> DM devices support DAX, and not have it half defined by that and half by the
> DM_TYPE_DAX_BIO_BASED.

My hope is that you can ignore the DM-internal book-keeping
(DM_TYPE_DAX_BIO_BASED) for now and just focus on fixing the real issue
of needing proper checking (as well as properly _not_ setting
QUEUE_FLAG_DAX in the case of pmem "raw").

Please advise, thanks Ross!

Mike

Re: [PATCH v2 4/7] dm: prevent DAX mounts if not supported

[Ross Zwisler]

On Wed, Jun 20, 2018 at 11:17:49AM -0400, Mike Snitzer wrote:
> On Mon, Jun 04 2018 at  7:15pm -0400,
> Ross Zwisler <ross.zwisler@linux.intel.com> wrote:
> 
> > On Fri, Jun 01, 2018 at 05:55:13PM -0400, Mike Snitzer wrote:
> > > On Tue, May 29 2018 at  3:51pm -0400,
> > > Ross Zwisler <ross.zwisler@linux.intel.com> wrote:
> > > 
> > > > Currently the code in dm_dax_direct_access() only checks whether the target
> > > > type has a direct_access() operation defined, not whether the underlying
> > > > block devices all support DAX.  This latter property can be seen by looking
> > > > at whether we set the QUEUE_FLAG_DAX request queue flag when creating the
> > > > DM device.
> > > 
> > > Wait... I thought DAX support was all or nothing?
> > 
> > Right, it is, and that's what I'm trying to capture.  The point of this series
> > is to make sure that we don't use DAX thru DM if one of the DM members doesn't
> > support DAX.
> > 
> > This is a bit tricky, though, because as you've pointed out there are a lot of
> > elements that go into a block device actually supporting DAX.  
> > 
> > First, the block device has to have a direct_access() operation defined in its
> > struct dax_operations table.  This is a static definition in the drivers,
> > though, so it's necessary but not sufficient.  For example, the PMEM driver
> > always defines a direct_access() operation, but depending on the mode of the
> > namespace (raw, fsdax or sector) it may or may not support DAX.
> > 
> > The next step is that a driver needs to say that he block queue supports
> > QUEUE_FLAG_DAX.  This again is necessary but not sufficient.  The PMEM driver
> > currently sets this for all namespace modes, but I agree that this should be
> > restricted to modes that support DAX.  Even once we do that, though, for the
> > block driver this isn't fully sufficient.  We'd really like users to call
> > bdev_dax_supported() so it can run some additional tests to make sure that DAX
> > will work.
> > 
> > So, the real test that filesystems rely on is bdev_dax_suppported().
> > 
> > The trick is that with DM we need to verify each block device via
> > bdev_dax_supported() just like a filesystem would, and then have some way of
> > communicating the result of all those checks to the filesystem which is
> > eventually mounted on the DM device.  At DAX mount time the filesystem will
> > call bdev_dax_supported() on the DM device, but it'll really only check the
> > first device.  
> > 
> > So, the strategy is to have DM manually check each member device via
> > bdev_dax_supported() then if they all pass set QUEUE_FLAG_DAX.  This then
> > becomes our one source of truth on whether or not a DM device supports DAX.
> > When the filesystem mounts with DAX support it'll also run
> > bdev_dax_supported(), but if we have QUEUE_FLAG_DAX set on the DM device, we
> > know that this check will pass.
> > 
> > > > This is problematic if we have, for example, a dm-linear device made up of
> > > > a PMEM namespace in fsdax mode followed by a ramdisk from BRD.
> > > > QUEUE_FLAG_DAX won't be set on the dm-linear device's request queue, but
> > > > we have a working direct_access() entry point and the first member of the
> > > > dm-linear set *does* support DAX.
> > > 
> > > If you don't have a uniformly capable device then it is very dangerous
> > > to advertise that the entire device has a certain capability.  That
> > > completely bit me in the past with discard (because for every IO I
> > > wasn't then checking if the destination device supported discards).
> > >
> > > It is all well and good that you're adding that check here.  But what I
> > > don't like is how you're saying QUEUE_FLAG_DAX implies direct_access()
> > > operation exists.. yet for raw PMEM namespaces we just discussed how
> > > that is a lie.
> > 
> > QUEUE_FLAG_DAX does imply that direct_access() exits.  However, as discussed
> > above for a given bdev we really do need to check bdev_dax_supported().
> > 
> > > SO this type of change showcases how the QUEUE_FLAG_DAX doesn't _really_
> > > imply direct_access() exists.
> > > 
> > > > This allows the user to create a filesystem on the dm-linear device, and
> > > > then mount it with DAX.  The filesystem's bdev_dax_supported() test will
> > > > pass because it'll operate on the first member of the dm-linear device,
> > > > which happens to be a fsdax PMEM namespace.
> > > > 
> > > > All DAX I/O will then fail to that dm-linear device because the lack of
> > > > QUEUE_FLAG_DAX prevents fs_dax_get_by_bdev() from working.  This means that
> > > > the struct dax_device isn't ever set in the filesystem, so
> > > > dax_direct_access() will always return -EOPNOTSUPP.
> > > 
> > > Now you've lost me... these past 2 paragraphs.  Why can a user mount it
> > > is DAX mode?  Because bdev_dax_supported() only accesses the first
> > > portion (which happens to have DAX capabilities?)
> > 
> > Right.  bdev_dax_supported() runs all of its checks, and because they are
> > running against the first block device in the dm set, they all pass.  But the
> > overall DM device does not actually support DAX.
> > 
> > > Isn't this exactly why you should be checking for QUEUE_FLAG_DAX in the
> > > caller (bdev_dax_supported)?  Why not use bdev_get_queue() and verify
> > > QUEUE_FLAG_DAX is set in there?
> > 
> > I'll look into that for the next revision, thanks.
> 
> Have you made any progress on a new revision?
> 
> > > > By failing out of dm_dax_direct_access() if QUEUE_FLAG_DAX isn't set we let
> > > > the filesystem know we don't support DAX at mount time.  The filesystem
> > > > will then silently fall back and remove the dax mount option, causing it to
> > > > work properly.
> > > 
> > > This shouldn't be needed.  Again, QUEUE_FLAG_DAX wasn't set.. so don't
> > > allow code to falsely try operations that should've been gated by the
> > > fact it wasn't set.
> > 
> > Right, the goal is to make QUEUE_FLAG_DAX our one source of truth for whether
> > DM devices support DAX, and not have it half defined by that and half by the
> > DM_TYPE_DAX_BIO_BASED.
> 
> My hope is that you can ignore the DM-internal book-keeping
> (DM_TYPE_DAX_BIO_BASED) for now and just focus on fixing the real issue
> of needing proper checking (as well as properly _not_ setting
> QUEUE_FLAG_DAX in the case of pmem "raw").
> 
> Please advise, thanks Ross!

I'm back working on this, and will send out another revision in the next day
or so.

[PATCH v2 5/7] dm: remove DM_TYPE_DAX_BIO_BASED dm_queue_mode

[Ross Zwisler]

The DM_TYPE_DAX_BIO_BASED dm_queue_mode was introduced to prevent DM
devices that could possibly support DAX from transitioning into DM devices
that cannot support DAX.

For example, the following transition will currently fail:

 dm-linear: [fsdax pmem][fsdax pmem] => [fsdax pmem][fsdax raw]
	      DM_TYPE_DAX_BIO_BASED       DM_TYPE_BIO_BASED

but these will both succeed:

 dm-linear: [fsdax pmem][brd ramdisk] => [fsdax pmem][fsdax raw]
 		DM_TYPE_DAX_BASED        DM_TYPE_BIO_BASED

 dm-linear: [fsdax pmem][fsdax raw] => [fsdax pmem][fsdax pmem]
 		DM_TYPE_BIO_BASED        DM_TYPE_DAX_BIO_BASED

This seems arbitrary, as really the choice on whether to use DAX happens at
filesystem mount time.  There's no guarantee that the in the first case
(double fsdax pmem) we were using the dax mount option with our file
system.

Instead, get rid of DM_TYPE_DAX_BIO_BASED and all the special casing around
it, and instead make the request queue's QUEUE_FLAG_DAX be our one source
of truth.  If this is set, we can use DAX, and if not, not.  We keep this
up to date in table_load() as the table changes.  As with regular block
devices the filesystem will then know at mount time whether DAX is a
supported mount option or not.

Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
---
 drivers/md/dm-ioctl.c         | 16 ++++++----------
 drivers/md/dm-table.c         | 25 ++++++++++---------------
 drivers/md/dm.c               |  2 --
 include/linux/device-mapper.h |  8 ++++++--
 4 files changed, 22 insertions(+), 29 deletions(-)

diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 5acf77de5945..d1f86d0bb2d0 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -1292,15 +1292,6 @@ static int populate_table(struct dm_table *table,
 	return dm_table_complete(table);
 }
 
-static bool is_valid_type(enum dm_queue_mode cur, enum dm_queue_mode new)
-{
-	if (cur == new ||
-	    (cur == DM_TYPE_BIO_BASED && new == DM_TYPE_DAX_BIO_BASED))
-		return true;
-
-	return false;
-}
-
 static int table_load(struct file *filp, struct dm_ioctl *param, size_t param_size)
 {
 	int r;
@@ -1343,12 +1334,17 @@ static int table_load(struct file *filp, struct dm_ioctl *param, size_t param_si
 			DMWARN("unable to set up device queue for new table.");
 			goto err_unlock_md_type;
 		}
-	} else if (!is_valid_type(dm_get_md_type(md), dm_table_get_type(t))) {
+	} else if (dm_get_md_type(md) != dm_table_get_type(t)) {
 		DMWARN("can't change device type after initial table load.");
 		r = -EINVAL;
 		goto err_unlock_md_type;
 	}
 
+	if (dm_table_supports_dax(t))
+		blk_queue_flag_set(QUEUE_FLAG_DAX, md->queue);
+	else
+		blk_queue_flag_clear(QUEUE_FLAG_DAX, md->queue);
+
 	dm_unlock_md_type(md);
 
 	/* stage inactive table */
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 5bb994b012ca..ea5c4a1e6f5b 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -866,7 +866,6 @@ EXPORT_SYMBOL(dm_consume_args);
 static bool __table_type_bio_based(enum dm_queue_mode table_type)
 {
 	return (table_type == DM_TYPE_BIO_BASED ||
-		table_type == DM_TYPE_DAX_BIO_BASED ||
 		table_type == DM_TYPE_NVME_BIO_BASED);
 }
 
@@ -888,7 +887,7 @@ static int device_supports_dax(struct dm_target *ti, struct dm_dev *dev,
 	return bdev_dax_supported(dev->bdev, PAGE_SIZE);
 }
 
-static bool dm_table_supports_dax(struct dm_table *t)
+bool dm_table_supports_dax(struct dm_table *t)
 {
 	struct dm_target *ti;
 	unsigned i;
@@ -907,6 +906,7 @@ static bool dm_table_supports_dax(struct dm_table *t)
 
 	return true;
 }
+EXPORT_SYMBOL_GPL(dm_table_supports_dax);
 
 static bool dm_table_does_not_support_partial_completion(struct dm_table *t);
 
@@ -944,7 +944,6 @@ static int dm_table_determine_type(struct dm_table *t)
 			/* possibly upgrade to a variant of bio-based */
 			goto verify_bio_based;
 		}
-		BUG_ON(t->type == DM_TYPE_DAX_BIO_BASED);
 		BUG_ON(t->type == DM_TYPE_NVME_BIO_BASED);
 		goto verify_rq_based;
 	}
@@ -981,18 +980,14 @@ static int dm_table_determine_type(struct dm_table *t)
 verify_bio_based:
 		/* We must use this table as bio-based */
 		t->type = DM_TYPE_BIO_BASED;
-		if (dm_table_supports_dax(t) ||
-		    (list_empty(devices) && live_md_type == DM_TYPE_DAX_BIO_BASED)) {
-			t->type = DM_TYPE_DAX_BIO_BASED;
-		} else {
-			/* Check if upgrading to NVMe bio-based is valid or required */
-			tgt = dm_table_get_immutable_target(t);
-			if (tgt && !tgt->max_io_len && dm_table_does_not_support_partial_completion(t)) {
-				t->type = DM_TYPE_NVME_BIO_BASED;
-				goto verify_rq_based; /* must be stacked directly on NVMe (blk-mq) */
-			} else if (list_empty(devices) && live_md_type == DM_TYPE_NVME_BIO_BASED) {
-				t->type = DM_TYPE_NVME_BIO_BASED;
-			}
+
+		/* Check if upgrading to NVMe bio-based is valid or required */
+		tgt = dm_table_get_immutable_target(t);
+		if (tgt && !tgt->max_io_len && dm_table_does_not_support_partial_completion(t)) {
+			t->type = DM_TYPE_NVME_BIO_BASED;
+			goto verify_rq_based; /* must be stacked directly on NVMe (blk-mq) */
+		} else if (list_empty(devices) && live_md_type == DM_TYPE_NVME_BIO_BASED) {
+			t->type = DM_TYPE_NVME_BIO_BASED;
 		}
 		return 0;
 	}
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 9728433362d1..0ce06fa292fd 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -2192,7 +2192,6 @@ int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t)
 		}
 		break;
 	case DM_TYPE_BIO_BASED:
-	case DM_TYPE_DAX_BIO_BASED:
 		dm_init_normal_md_queue(md);
 		blk_queue_make_request(md->queue, dm_make_request);
 		break;
@@ -2910,7 +2909,6 @@ struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, enum dm_qu
 
 	switch (type) {
 	case DM_TYPE_BIO_BASED:
-	case DM_TYPE_DAX_BIO_BASED:
 	case DM_TYPE_NVME_BIO_BASED:
 		pool_size = max(dm_get_reserved_bio_based_ios(), min_pool_size);
 		front_pad = roundup(per_io_data_size, __alignof__(struct dm_target_io)) + offsetof(struct dm_target_io, clone);
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index 31fef7c34185..cbf3d7e7ed33 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -27,8 +27,7 @@ enum dm_queue_mode {
 	DM_TYPE_BIO_BASED	 = 1,
 	DM_TYPE_REQUEST_BASED	 = 2,
 	DM_TYPE_MQ_REQUEST_BASED = 3,
-	DM_TYPE_DAX_BIO_BASED	 = 4,
-	DM_TYPE_NVME_BIO_BASED	 = 5,
+	DM_TYPE_NVME_BIO_BASED	 = 4,
 };
 
 typedef enum { STATUSTYPE_INFO, STATUSTYPE_TABLE } status_type_t;
@@ -460,6 +459,11 @@ void dm_table_add_target_callbacks(struct dm_table *t, struct dm_target_callback
  */
 void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type);
 
+/*
+ * Check to see if this target type and all table devices support DAX.
+ */
+bool dm_table_supports_dax(struct dm_table *t);
+
 /*
  * Finally call this to make the table ready for use.
  */
-- 
2.14.3

Re: [PATCH v2 5/7] dm: remove DM_TYPE_DAX_BIO_BASED dm_queue_mode

[Mike Snitzer]

On Tue, May 29 2018 at  3:51pm -0400,
Ross Zwisler <ross.zwisler@linux.intel.com> wrote:

> The DM_TYPE_DAX_BIO_BASED dm_queue_mode was introduced to prevent DM
> devices that could possibly support DAX from transitioning into DM devices
> that cannot support DAX.
> 
> For example, the following transition will currently fail:
> 
>  dm-linear: [fsdax pmem][fsdax pmem] => [fsdax pmem][fsdax raw]
> 	      DM_TYPE_DAX_BIO_BASED       DM_TYPE_BIO_BASED
> 
> but these will both succeed:
> 
>  dm-linear: [fsdax pmem][brd ramdisk] => [fsdax pmem][fsdax raw]
>  	      DM_TYPE_DAX_BIO_BASED        DM_TYPE_BIO_BASED
> 

I fail to see how this succeeds given
drivers/md/dm-ioctl.c:is_valid_type() only allows transitions from:

DM_TYPE_BIO_BASED => DM_TYPE_DAX_BIO_BASED

>  dm-linear: [fsdax pmem][fsdax raw] => [fsdax pmem][fsdax pmem]
>  		DM_TYPE_BIO_BASED        DM_TYPE_DAX_BIO_BASED
> 
> This seems arbitrary, as really the choice on whether to use DAX happens at
> filesystem mount time.  There's no guarantee that the in the first case
> (double fsdax pmem) we were using the dax mount option with our file
> system.
> 
> Instead, get rid of DM_TYPE_DAX_BIO_BASED and all the special casing around
> it, and instead make the request queue's QUEUE_FLAG_DAX be our one source
> of truth.  If this is set, we can use DAX, and if not, not.  We keep this
> up to date in table_load() as the table changes.  As with regular block
> devices the filesystem will then know at mount time whether DAX is a
> supported mount option or not.

If you don't think you need this specialization that is fine.. but DM
devices supporting suspending (as part of table reloads) so is there any
risk that there will be inflight IO (say if someone did 'dmsetup suspend
--noflush').. and then upon reload the device type changed out from
under us.. anyway, I don't have all the PMEM DAX stuff paged back into
my head yet.

But this just seems like we really shouldn't be allowing the
transition from what was DM_TYPE_DAX_BIO_BASED back to DM_TYPE_BIO_BASED

Mike

> Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
> ---
>  drivers/md/dm-ioctl.c         | 16 ++++++----------
>  drivers/md/dm-table.c         | 25 ++++++++++---------------
>  drivers/md/dm.c               |  2 --
>  include/linux/device-mapper.h |  8 ++++++--
>  4 files changed, 22 insertions(+), 29 deletions(-)
> 
> diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
> index 5acf77de5945..d1f86d0bb2d0 100644
> --- a/drivers/md/dm-ioctl.c
> +++ b/drivers/md/dm-ioctl.c
> @@ -1292,15 +1292,6 @@ static int populate_table(struct dm_table *table,
>  	return dm_table_complete(table);
>  }
>  
> -static bool is_valid_type(enum dm_queue_mode cur, enum dm_queue_mode new)
> -{
> -	if (cur == new ||
> -	    (cur == DM_TYPE_BIO_BASED && new == DM_TYPE_DAX_BIO_BASED))
> -		return true;
> -
> -	return false;
> -}
> -
>  static int table_load(struct file *filp, struct dm_ioctl *param, size_t param_size)
>  {
>  	int r;
> @@ -1343,12 +1334,17 @@ static int table_load(struct file *filp, struct dm_ioctl *param, size_t param_si
>  			DMWARN("unable to set up device queue for new table.");
>  			goto err_unlock_md_type;
>  		}
> -	} else if (!is_valid_type(dm_get_md_type(md), dm_table_get_type(t))) {
> +	} else if (dm_get_md_type(md) != dm_table_get_type(t)) {
>  		DMWARN("can't change device type after initial table load.");
>  		r = -EINVAL;
>  		goto err_unlock_md_type;
>  	}
>  
> +	if (dm_table_supports_dax(t))
> +		blk_queue_flag_set(QUEUE_FLAG_DAX, md->queue);
> +	else
> +		blk_queue_flag_clear(QUEUE_FLAG_DAX, md->queue);
> +
>  	dm_unlock_md_type(md);
>  
>  	/* stage inactive table */
> diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
> index 5bb994b012ca..ea5c4a1e6f5b 100644
> --- a/drivers/md/dm-table.c
> +++ b/drivers/md/dm-table.c
> @@ -866,7 +866,6 @@ EXPORT_SYMBOL(dm_consume_args);
>  static bool __table_type_bio_based(enum dm_queue_mode table_type)
>  {
>  	return (table_type == DM_TYPE_BIO_BASED ||
> -		table_type == DM_TYPE_DAX_BIO_BASED ||
>  		table_type == DM_TYPE_NVME_BIO_BASED);
>  }
>  
> @@ -888,7 +887,7 @@ static int device_supports_dax(struct dm_target *ti, struct dm_dev *dev,
>  	return bdev_dax_supported(dev->bdev, PAGE_SIZE);
>  }
>  
> -static bool dm_table_supports_dax(struct dm_table *t)
> +bool dm_table_supports_dax(struct dm_table *t)
>  {
>  	struct dm_target *ti;
>  	unsigned i;
> @@ -907,6 +906,7 @@ static bool dm_table_supports_dax(struct dm_table *t)
>  
>  	return true;
>  }
> +EXPORT_SYMBOL_GPL(dm_table_supports_dax);
>  
>  static bool dm_table_does_not_support_partial_completion(struct dm_table *t);
>  
> @@ -944,7 +944,6 @@ static int dm_table_determine_type(struct dm_table *t)
>  			/* possibly upgrade to a variant of bio-based */
>  			goto verify_bio_based;
>  		}
> -		BUG_ON(t->type == DM_TYPE_DAX_BIO_BASED);
>  		BUG_ON(t->type == DM_TYPE_NVME_BIO_BASED);
>  		goto verify_rq_based;
>  	}
> @@ -981,18 +980,14 @@ static int dm_table_determine_type(struct dm_table *t)
>  verify_bio_based:
>  		/* We must use this table as bio-based */
>  		t->type = DM_TYPE_BIO_BASED;
> -		if (dm_table_supports_dax(t) ||
> -		    (list_empty(devices) && live_md_type == DM_TYPE_DAX_BIO_BASED)) {
> -			t->type = DM_TYPE_DAX_BIO_BASED;
> -		} else {
> -			/* Check if upgrading to NVMe bio-based is valid or required */
> -			tgt = dm_table_get_immutable_target(t);
> -			if (tgt && !tgt->max_io_len && dm_table_does_not_support_partial_completion(t)) {
> -				t->type = DM_TYPE_NVME_BIO_BASED;
> -				goto verify_rq_based; /* must be stacked directly on NVMe (blk-mq) */
> -			} else if (list_empty(devices) && live_md_type == DM_TYPE_NVME_BIO_BASED) {
> -				t->type = DM_TYPE_NVME_BIO_BASED;
> -			}
> +
> +		/* Check if upgrading to NVMe bio-based is valid or required */
> +		tgt = dm_table_get_immutable_target(t);
> +		if (tgt && !tgt->max_io_len && dm_table_does_not_support_partial_completion(t)) {
> +			t->type = DM_TYPE_NVME_BIO_BASED;
> +			goto verify_rq_based; /* must be stacked directly on NVMe (blk-mq) */
> +		} else if (list_empty(devices) && live_md_type == DM_TYPE_NVME_BIO_BASED) {
> +			t->type = DM_TYPE_NVME_BIO_BASED;
>  		}
>  		return 0;
>  	}
> diff --git a/drivers/md/dm.c b/drivers/md/dm.c
> index 9728433362d1..0ce06fa292fd 100644
> --- a/drivers/md/dm.c
> +++ b/drivers/md/dm.c
> @@ -2192,7 +2192,6 @@ int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t)
>  		}
>  		break;
>  	case DM_TYPE_BIO_BASED:
> -	case DM_TYPE_DAX_BIO_BASED:
>  		dm_init_normal_md_queue(md);
>  		blk_queue_make_request(md->queue, dm_make_request);
>  		break;
> @@ -2910,7 +2909,6 @@ struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, enum dm_qu
>  
>  	switch (type) {
>  	case DM_TYPE_BIO_BASED:
> -	case DM_TYPE_DAX_BIO_BASED:
>  	case DM_TYPE_NVME_BIO_BASED:
>  		pool_size = max(dm_get_reserved_bio_based_ios(), min_pool_size);
>  		front_pad = roundup(per_io_data_size, __alignof__(struct dm_target_io)) + offsetof(struct dm_target_io, clone);
> diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
> index 31fef7c34185..cbf3d7e7ed33 100644
> --- a/include/linux/device-mapper.h
> +++ b/include/linux/device-mapper.h
> @@ -27,8 +27,7 @@ enum dm_queue_mode {
>  	DM_TYPE_BIO_BASED	 = 1,
>  	DM_TYPE_REQUEST_BASED	 = 2,
>  	DM_TYPE_MQ_REQUEST_BASED = 3,
> -	DM_TYPE_DAX_BIO_BASED	 = 4,
> -	DM_TYPE_NVME_BIO_BASED	 = 5,
> +	DM_TYPE_NVME_BIO_BASED	 = 4,
>  };
>  
>  typedef enum { STATUSTYPE_INFO, STATUSTYPE_TABLE } status_type_t;
> @@ -460,6 +459,11 @@ void dm_table_add_target_callbacks(struct dm_table *t, struct dm_target_callback
>   */
>  void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type);
>  
> +/*
> + * Check to see if this target type and all table devices support DAX.
> + */
> +bool dm_table_supports_dax(struct dm_table *t);
> +
>  /*
>   * Finally call this to make the table ready for use.
>   */
> -- 
> 2.14.3
> 

Re: [PATCH v2 5/7] dm: remove DM_TYPE_DAX_BIO_BASED dm_queue_mode

[Ross Zwisler]

On Fri, Jun 01, 2018 at 06:04:43PM -0400, Mike Snitzer wrote:
> On Tue, May 29 2018 at  3:51pm -0400,
> Ross Zwisler <ross.zwisler@linux.intel.com> wrote:
> 
> > The DM_TYPE_DAX_BIO_BASED dm_queue_mode was introduced to prevent DM
> > devices that could possibly support DAX from transitioning into DM devices
> > that cannot support DAX.
> > 
> > For example, the following transition will currently fail:
> > 
> >  dm-linear: [fsdax pmem][fsdax pmem] => [fsdax pmem][fsdax raw]
> > 	      DM_TYPE_DAX_BIO_BASED       DM_TYPE_BIO_BASED
> > 
> > but these will both succeed:
> > 
> >  dm-linear: [fsdax pmem][brd ramdisk] => [fsdax pmem][fsdax raw]
> >  	      DM_TYPE_DAX_BIO_BASED        DM_TYPE_BIO_BASED
> > 
> 
> I fail to see how this succeeds given
> drivers/md/dm-ioctl.c:is_valid_type() only allows transitions from:
> 
> DM_TYPE_BIO_BASED => DM_TYPE_DAX_BIO_BASED

Right, sorry, that was a typo.  What I meant was:

> For example, the following transition will currently fail:
> 
>  dm-linear: [fsdax pmem][fsdax pmem] => [fsdax pmem][fsdax raw]
>               DM_TYPE_DAX_BIO_BASED       DM_TYPE_BIO_BASED
> 
> but these will both succeed:
> 
>  dm-linear: [fsdax pmem][brd ramdisk] => [fsdax pmem][fsdax raw]
>                 DM_TYPE_BIO_BASED        DM_TYPE_BIO_BASED
> 
>  dm-linear: [fsdax pmem][fsdax raw] => [fsdax pmem][fsdax pmem]
>                 DM_TYPE_BIO_BASED        DM_TYPE_DAX_BIO_BASED

So we allow 2 of the 3 transitions, but the reason that we disallow the third
isn't fully clear to me.

> >  dm-linear: [fsdax pmem][fsdax raw] => [fsdax pmem][fsdax pmem]
> >  		DM_TYPE_BIO_BASED        DM_TYPE_DAX_BIO_BASED
> > 
> > This seems arbitrary, as really the choice on whether to use DAX happens at
> > filesystem mount time.  There's no guarantee that the in the first case
> > (double fsdax pmem) we were using the dax mount option with our file
> > system.
> > 
> > Instead, get rid of DM_TYPE_DAX_BIO_BASED and all the special casing around
> > it, and instead make the request queue's QUEUE_FLAG_DAX be our one source
> > of truth.  If this is set, we can use DAX, and if not, not.  We keep this
> > up to date in table_load() as the table changes.  As with regular block
> > devices the filesystem will then know at mount time whether DAX is a
> > supported mount option or not.
> 
> If you don't think you need this specialization that is fine.. but DM
> devices supporting suspending (as part of table reloads) so is there any
> risk that there will be inflight IO (say if someone did 'dmsetup suspend
> --noflush').. and then upon reload the device type changed out from
> under us.. anyway, I don't have all the PMEM DAX stuff paged back into
> my head yet.
> 
> But this just seems like we really shouldn't be allowing the
> transition from what was DM_TYPE_DAX_BIO_BASED back to DM_TYPE_BIO_BASED

I admit I don't fully understand all the ways that DM supports suspending and
resuming devices.  Is there actually a case where we can change out the DM
devices while I/O is running, and somehow end up trying to issue a DAX I/O to
a device that doesn't support DAX?

Toshi, do you have a test case that shows this somehow?

Re: [PATCH v2 5/7] dm: remove DM_TYPE_DAX_BIO_BASED dm_queue_mode

[Kani, Toshi]

On Mon, 2018-06-04 at 17:24 -0600, Ross Zwisler wrote:
> On Fri, Jun 01, 2018 at 06:04:43PM -0400, Mike Snitzer wrote:
> > On Tue, May 29 2018 at  3:51pm -0400,
> > Ross Zwisler <ross.zwisler@linux.intel.com> wrote:
 :
> > For example, the following transition will currently fail:
> > 
> >  dm-linear: [fsdax pmem][fsdax pmem] => [fsdax pmem][fsdax raw]
> >               DM_TYPE_DAX_BIO_BASED       DM_TYPE_BIO_BASED
> > 
> > but these will both succeed:
> > 
> >  dm-linear: [fsdax pmem][brd ramdisk] => [fsdax pmem][fsdax raw]
> >                 DM_TYPE_BIO_BASED        DM_TYPE_BIO_BASED
> > 
> >  dm-linear: [fsdax pmem][fsdax raw] => [fsdax pmem][fsdax pmem]
> >                 DM_TYPE_BIO_BASED        DM_TYPE_DAX_BIO_BASED
> 
> So we allow 2 of the 3 transitions, but the reason that we disallow the third
> isn't fully clear to me.

I need to refresh my memory for the code, but here is the intent.
https://lkml.org/lkml/2016/6/22/1000
https://lkml.org/lkml/2016/6/22/999


> > >  dm-linear: [fsdax pmem][fsdax raw] => [fsdax pmem][fsdax pmem]
> > >  		DM_TYPE_BIO_BASED        DM_TYPE_DAX_BIO_BASED
> > > 
> > > This seems arbitrary, as really the choice on whether to use DAX happens at
> > > filesystem mount time.  There's no guarantee that the in the first case
> > > (double fsdax pmem) we were using the dax mount option with our file
> > > system.
> > > 
> > > Instead, get rid of DM_TYPE_DAX_BIO_BASED and all the special casing around
> > > it, and instead make the request queue's QUEUE_FLAG_DAX be our one source
> > > of truth.  If this is set, we can use DAX, and if not, not.  We keep this
> > > up to date in table_load() as the table changes.  As with regular block
> > > devices the filesystem will then know at mount time whether DAX is a
> > > supported mount option or not.
> > 
> > If you don't think you need this specialization that is fine.. but DM
> > devices supporting suspending (as part of table reloads) so is there any
> > risk that there will be inflight IO (say if someone did 'dmsetup suspend
> > --noflush').. and then upon reload the device type changed out from
> > under us.. anyway, I don't have all the PMEM DAX stuff paged back into
> > my head yet.
> > 
> > But this just seems like we really shouldn't be allowing the
> > transition from what was DM_TYPE_DAX_BIO_BASED back to DM_TYPE_BIO_BASED
> 
> I admit I don't fully understand all the ways that DM supports suspending and
> resuming devices.  Is there actually a case where we can change out the DM
> devices while I/O is running, and somehow end up trying to issue a DAX I/O to
> a device that doesn't support DAX?
> 
> Toshi, do you have a test case that shows this somehow?

No, I did not test suspend/resume since HPE servers do not support it.

Thanks,
-Toshi

Re: [PATCH v2 5/7] dm: remove DM_TYPE_DAX_BIO_BASED dm_queue_mode

[Mike Snitzer]

On Mon, Jun 04 2018 at  7:24pm -0400,
Ross Zwisler <ross.zwisler@linux.intel.com> wrote:

> On Fri, Jun 01, 2018 at 06:04:43PM -0400, Mike Snitzer wrote:
> > On Tue, May 29 2018 at  3:51pm -0400,
> > Ross Zwisler <ross.zwisler@linux.intel.com> wrote:
> > 
> > > The DM_TYPE_DAX_BIO_BASED dm_queue_mode was introduced to prevent DM
> > > devices that could possibly support DAX from transitioning into DM devices
> > > that cannot support DAX.
> > > 
> > > For example, the following transition will currently fail:
> > > 
> > >  dm-linear: [fsdax pmem][fsdax pmem] => [fsdax pmem][fsdax raw]
> > > 	      DM_TYPE_DAX_BIO_BASED       DM_TYPE_BIO_BASED
> > > 
> > > but these will both succeed:
> > > 
> > >  dm-linear: [fsdax pmem][brd ramdisk] => [fsdax pmem][fsdax raw]
> > >  	      DM_TYPE_DAX_BIO_BASED        DM_TYPE_BIO_BASED
> > > 
> > 
> > I fail to see how this succeeds given
> > drivers/md/dm-ioctl.c:is_valid_type() only allows transitions from:
> > 
> > DM_TYPE_BIO_BASED => DM_TYPE_DAX_BIO_BASED
> 
> Right, sorry, that was a typo.  What I meant was:
> 
> > For example, the following transition will currently fail:
> > 
> >  dm-linear: [fsdax pmem][fsdax pmem] => [fsdax pmem][fsdax raw]
> >               DM_TYPE_DAX_BIO_BASED       DM_TYPE_BIO_BASED
> > 
> > but these will both succeed:
> > 
> >  dm-linear: [fsdax pmem][brd ramdisk] => [fsdax pmem][fsdax raw]
> >                 DM_TYPE_BIO_BASED        DM_TYPE_BIO_BASED
> > 
> >  dm-linear: [fsdax pmem][fsdax raw] => [fsdax pmem][fsdax pmem]
> >                 DM_TYPE_BIO_BASED        DM_TYPE_DAX_BIO_BASED
> 
> So we allow 2 of the 3 transitions, but the reason that we disallow the third
> isn't fully clear to me.
> 
> > >  dm-linear: [fsdax pmem][fsdax raw] => [fsdax pmem][fsdax pmem]
> > >  		DM_TYPE_BIO_BASED        DM_TYPE_DAX_BIO_BASED
> > > 
> > > This seems arbitrary, as really the choice on whether to use DAX happens at
> > > filesystem mount time.  There's no guarantee that the in the first case
> > > (double fsdax pmem) we were using the dax mount option with our file
> > > system.
> > > 
> > > Instead, get rid of DM_TYPE_DAX_BIO_BASED and all the special casing around
> > > it, and instead make the request queue's QUEUE_FLAG_DAX be our one source
> > > of truth.  If this is set, we can use DAX, and if not, not.  We keep this
> > > up to date in table_load() as the table changes.  As with regular block
> > > devices the filesystem will then know at mount time whether DAX is a
> > > supported mount option or not.
> > 
> > If you don't think you need this specialization that is fine.. but DM
> > devices supporting suspending (as part of table reloads) so is there any
> > risk that there will be inflight IO (say if someone did 'dmsetup suspend
> > --noflush').. and then upon reload the device type changed out from
> > under us.. anyway, I don't have all the PMEM DAX stuff paged back into
> > my head yet.
> > 
> > But this just seems like we really shouldn't be allowing the
> > transition from what was DM_TYPE_DAX_BIO_BASED back to DM_TYPE_BIO_BASED
> 
> I admit I don't fully understand all the ways that DM supports suspending and
> resuming devices.  Is there actually a case where we can change out the DM
> devices while I/O is running, and somehow end up trying to issue a DAX I/O to
> a device that doesn't support DAX?

Yes, provided root permissions, it's very easy to dmsetup suspend/load/resume
to replace any portion of the DM device's logical address space to map to an
entirely different DM target (with a different backing store).  It's
pretty intrusive to do such things, but easily done and powerful.

Mike

Re: [PATCH v2 5/7] dm: remove DM_TYPE_DAX_BIO_BASED dm_queue_mode

[Ross Zwisler]

On Mon, Jun 04, 2018 at 08:46:28PM -0400, Mike Snitzer wrote:
> On Mon, Jun 04 2018 at  7:24pm -0400,
> Ross Zwisler <ross.zwisler@linux.intel.com> wrote:
> 
> > On Fri, Jun 01, 2018 at 06:04:43PM -0400, Mike Snitzer wrote:
> > > On Tue, May 29 2018 at  3:51pm -0400,
> > > Ross Zwisler <ross.zwisler@linux.intel.com> wrote:
> > > 
> > > > The DM_TYPE_DAX_BIO_BASED dm_queue_mode was introduced to prevent DM
> > > > devices that could possibly support DAX from transitioning into DM devices
> > > > that cannot support DAX.
> > > > 
> > > > For example, the following transition will currently fail:
> > > > 
> > > >  dm-linear: [fsdax pmem][fsdax pmem] => [fsdax pmem][fsdax raw]
> > > > 	      DM_TYPE_DAX_BIO_BASED       DM_TYPE_BIO_BASED
> > > > 
> > > > but these will both succeed:
> > > > 
> > > >  dm-linear: [fsdax pmem][brd ramdisk] => [fsdax pmem][fsdax raw]
> > > >  	      DM_TYPE_DAX_BIO_BASED        DM_TYPE_BIO_BASED
> > > > 
> > > 
> > > I fail to see how this succeeds given
> > > drivers/md/dm-ioctl.c:is_valid_type() only allows transitions from:
> > > 
> > > DM_TYPE_BIO_BASED => DM_TYPE_DAX_BIO_BASED
> > 
> > Right, sorry, that was a typo.  What I meant was:
> > 
> > > For example, the following transition will currently fail:
> > > 
> > >  dm-linear: [fsdax pmem][fsdax pmem] => [fsdax pmem][fsdax raw]
> > >               DM_TYPE_DAX_BIO_BASED       DM_TYPE_BIO_BASED
> > > 
> > > but these will both succeed:
> > > 
> > >  dm-linear: [fsdax pmem][brd ramdisk] => [fsdax pmem][fsdax raw]
> > >                 DM_TYPE_BIO_BASED        DM_TYPE_BIO_BASED
> > > 
> > >  dm-linear: [fsdax pmem][fsdax raw] => [fsdax pmem][fsdax pmem]
> > >                 DM_TYPE_BIO_BASED        DM_TYPE_DAX_BIO_BASED
> > 
> > So we allow 2 of the 3 transitions, but the reason that we disallow the third
> > isn't fully clear to me.
> > 
> > > >  dm-linear: [fsdax pmem][fsdax raw] => [fsdax pmem][fsdax pmem]
> > > >  		DM_TYPE_BIO_BASED        DM_TYPE_DAX_BIO_BASED
> > > > 
> > > > This seems arbitrary, as really the choice on whether to use DAX happens at
> > > > filesystem mount time.  There's no guarantee that the in the first case
> > > > (double fsdax pmem) we were using the dax mount option with our file
> > > > system.
> > > > 
> > > > Instead, get rid of DM_TYPE_DAX_BIO_BASED and all the special casing around
> > > > it, and instead make the request queue's QUEUE_FLAG_DAX be our one source
> > > > of truth.  If this is set, we can use DAX, and if not, not.  We keep this
> > > > up to date in table_load() as the table changes.  As with regular block
> > > > devices the filesystem will then know at mount time whether DAX is a
> > > > supported mount option or not.
> > > 
> > > If you don't think you need this specialization that is fine.. but DM
> > > devices supporting suspending (as part of table reloads) so is there any
> > > risk that there will be inflight IO (say if someone did 'dmsetup suspend
> > > --noflush').. and then upon reload the device type changed out from
> > > under us.. anyway, I don't have all the PMEM DAX stuff paged back into
> > > my head yet.
> > > 
> > > But this just seems like we really shouldn't be allowing the
> > > transition from what was DM_TYPE_DAX_BIO_BASED back to DM_TYPE_BIO_BASED
> > 
> > I admit I don't fully understand all the ways that DM supports suspending and
> > resuming devices.  Is there actually a case where we can change out the DM
> > devices while I/O is running, and somehow end up trying to issue a DAX I/O to
> > a device that doesn't support DAX?
> 
> Yes, provided root permissions, it's very easy to dmsetup suspend/load/resume
> to replace any portion of the DM device's logical address space to map to an
> entirely different DM target (with a different backing store).  It's
> pretty intrusive to do such things, but easily done and powerful.
> 
> Mike

Hmmm, I don't understand how you can do this if there is a filesystem built on
your DM device?  Say you have a DM device, either striped or linear, that is
made up of 2 devices, and then you use dmsetup to replace one of the DM member
devices with something else.  You've just swapped out half of your LBA space
with new data, right? 

I don't understand how you can expect a filesystem built on the old DM device
to still work?  You especially can't do this while the filesystem is mounted -
all the in-core filesystem metadata would be garbage because the on-media data
would have totally changed.

So, when dealing with a filesystem, the flow must be:

unmount your filesystem
redo your DM device, changing out devices
reformat your filesystem on the new DM device
remount your filesystem

Right?  If so, then I don't see how a transition of the DM device from
supporting DAX to not supporting DAX or vice versa could harm us, as we can't
be doing filesystem I/O at the time when we change the composition of the DM
device.

Re: [PATCH v2 5/7] dm: remove DM_TYPE_DAX_BIO_BASED dm_queue_mode

[Mike Snitzer]

On Wed, Jun 06 2018 at  1:24P -0400,
Ross Zwisler <ross.zwisler@linux.intel.com> wrote:

> On Mon, Jun 04, 2018 at 08:46:28PM -0400, Mike Snitzer wrote:
> > On Mon, Jun 04 2018 at  7:24pm -0400,
> > Ross Zwisler <ross.zwisler@linux.intel.com> wrote:
> > 
> > > On Fri, Jun 01, 2018 at 06:04:43PM -0400, Mike Snitzer wrote:
> > > > On Tue, May 29 2018 at  3:51pm -0400,
> > > > Ross Zwisler <ross.zwisler@linux.intel.com> wrote:
> > > > 
> > > > > The DM_TYPE_DAX_BIO_BASED dm_queue_mode was introduced to prevent DM
> > > > > devices that could possibly support DAX from transitioning into DM devices
> > > > > that cannot support DAX.
> > > > > 
> > > > > For example, the following transition will currently fail:
> > > > > 
> > > > >  dm-linear: [fsdax pmem][fsdax pmem] => [fsdax pmem][fsdax raw]
> > > > > 	      DM_TYPE_DAX_BIO_BASED       DM_TYPE_BIO_BASED
> > > > > 
> > > > > but these will both succeed:
> > > > > 
> > > > >  dm-linear: [fsdax pmem][brd ramdisk] => [fsdax pmem][fsdax raw]
> > > > >  	      DM_TYPE_DAX_BIO_BASED        DM_TYPE_BIO_BASED
> > > > > 
> > > > 
> > > > I fail to see how this succeeds given
> > > > drivers/md/dm-ioctl.c:is_valid_type() only allows transitions from:
> > > > 
> > > > DM_TYPE_BIO_BASED => DM_TYPE_DAX_BIO_BASED
> > > 
> > > Right, sorry, that was a typo.  What I meant was:
> > > 
> > > > For example, the following transition will currently fail:
> > > > 
> > > >  dm-linear: [fsdax pmem][fsdax pmem] => [fsdax pmem][fsdax raw]
> > > >               DM_TYPE_DAX_BIO_BASED       DM_TYPE_BIO_BASED
> > > > 
> > > > but these will both succeed:
> > > > 
> > > >  dm-linear: [fsdax pmem][brd ramdisk] => [fsdax pmem][fsdax raw]
> > > >                 DM_TYPE_BIO_BASED        DM_TYPE_BIO_BASED
> > > > 
> > > >  dm-linear: [fsdax pmem][fsdax raw] => [fsdax pmem][fsdax pmem]
> > > >                 DM_TYPE_BIO_BASED        DM_TYPE_DAX_BIO_BASED
> > > 
> > > So we allow 2 of the 3 transitions, but the reason that we disallow the third
> > > isn't fully clear to me.
> > > 
> > > > >  dm-linear: [fsdax pmem][fsdax raw] => [fsdax pmem][fsdax pmem]
> > > > >  		DM_TYPE_BIO_BASED        DM_TYPE_DAX_BIO_BASED
> > > > > 
> > > > > This seems arbitrary, as really the choice on whether to use DAX happens at
> > > > > filesystem mount time.  There's no guarantee that the in the first case
> > > > > (double fsdax pmem) we were using the dax mount option with our file
> > > > > system.
> > > > > 
> > > > > Instead, get rid of DM_TYPE_DAX_BIO_BASED and all the special casing around
> > > > > it, and instead make the request queue's QUEUE_FLAG_DAX be our one source
> > > > > of truth.  If this is set, we can use DAX, and if not, not.  We keep this
> > > > > up to date in table_load() as the table changes.  As with regular block
> > > > > devices the filesystem will then know at mount time whether DAX is a
> > > > > supported mount option or not.
> > > > 
> > > > If you don't think you need this specialization that is fine.. but DM
> > > > devices supporting suspending (as part of table reloads) so is there any
> > > > risk that there will be inflight IO (say if someone did 'dmsetup suspend
> > > > --noflush').. and then upon reload the device type changed out from
> > > > under us.. anyway, I don't have all the PMEM DAX stuff paged back into
> > > > my head yet.
> > > > 
> > > > But this just seems like we really shouldn't be allowing the
> > > > transition from what was DM_TYPE_DAX_BIO_BASED back to DM_TYPE_BIO_BASED
> > > 
> > > I admit I don't fully understand all the ways that DM supports suspending and
> > > resuming devices.  Is there actually a case where we can change out the DM
> > > devices while I/O is running, and somehow end up trying to issue a DAX I/O to
> > > a device that doesn't support DAX?
> > 
> > Yes, provided root permissions, it's very easy to dmsetup suspend/load/resume
> > to replace any portion of the DM device's logical address space to map to an
> > entirely different DM target (with a different backing store).  It's
> > pretty intrusive to do such things, but easily done and powerful.
> > 
> > Mike
> 
> Hmmm, I don't understand how you can do this if there is a filesystem built on
> your DM device?  Say you have a DM device, either striped or linear, that is
> made up of 2 devices, and then you use dmsetup to replace one of the DM member
> devices with something else.  You've just swapped out half of your LBA space
> with new data, right? 
> 
> I don't understand how you can expect a filesystem built on the old DM device
> to still work?  You especially can't do this while the filesystem is mounted -
> all the in-core filesystem metadata would be garbage because the on-media data
> would have totally changed.

Sure it can cause you to no longer have access to the original backing
store (e.g. swapping in an "error" target instead of linear).

But this ability to suspend a DM device with a table that is using
"linear", load a new table (that uses a different target) into the
inactive table slot, and then resume to make the device active is how
things like snapshot support are achieved.  The "linear" target gets
replaced with "snapshot-origin', etc.
 
> So, when dealing with a filesystem, the flow must be:
> 
> unmount your filesystem
> redo your DM device, changing out devices
> reformat your filesystem on the new DM device
> remount your filesystem
> 
> Right?

No.

> If so, then I don't see how a transition of the DM device from
> supporting DAX to not supporting DAX or vice versa could harm us, as we can't
> be doing filesystem I/O at the time when we change the composition of the DM
> device.

Yes you can.  That is the entire point.

BTW, I'm not saying you have to change the backing store.  I'm saying
you _can_ if you would like.  Obviously if you remove the backing store
with the filesystem then you'll not be able to access the filesystem.

The point of all this is to say, DM table swaps can be good and
powerful.  But they can also be harmful.  The goal of preventing
transitions from DM_TYPE_DAX_BIO_BASED to DM_TYPE_BIO_BASED was to
shield users from doing obviously wrong things... things they might not
realize are problematic because of the relatively opaque nature of "DAX"
support.

Mike

[PATCH v2 6/7] dm-snap: remove unnecessary direct_access() stub

[Ross Zwisler]

This stub was added so that we could use dm-snap with DM_TYPE_DAX_BIO_BASED
mode devices.  That mode and the transition issues associated with it no
longer exist, so we can remove this dead code.

Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
---
 drivers/md/dm-snap.c | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index 216035be5661..0143b158d52d 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -2305,13 +2305,6 @@ static int origin_map(struct dm_target *ti, struct bio *bio)
 	return do_origin(o->dev, bio);
 }
 
-static long origin_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
-		long nr_pages, void **kaddr, pfn_t *pfn)
-{
-	DMWARN("device does not support dax.");
-	return -EIO;
-}
-
 /*
  * Set the target "max_io_len" field to the minimum of all the snapshots'
  * chunk sizes.
@@ -2371,7 +2364,6 @@ static struct target_type origin_target = {
 	.postsuspend = origin_postsuspend,
 	.status  = origin_status,
 	.iterate_devices = origin_iterate_devices,
-	.direct_access = origin_dax_direct_access,
 };
 
 static struct target_type snapshot_target = {
-- 
2.14.3

[PATCH v2 7/7] dm-error: remove unnecessary direct_access() stub

[Ross Zwisler]

This stub was added so that we could use dm-error with
DM_TYPE_DAX_BIO_BASED mode devices.  That mode and the transition issues
associated with it no longer exist, so we can remove this dead code.

Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
---
 drivers/md/dm-target.c | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/drivers/md/dm-target.c b/drivers/md/dm-target.c
index 314d17ca6466..c4dbc15f7862 100644
--- a/drivers/md/dm-target.c
+++ b/drivers/md/dm-target.c
@@ -140,12 +140,6 @@ static void io_err_release_clone_rq(struct request *clone)
 {
 }
 
-static long io_err_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
-		long nr_pages, void **kaddr, pfn_t *pfn)
-{
-	return -EIO;
-}
-
 static struct target_type error_target = {
 	.name = "error",
 	.version = {1, 5, 0},
@@ -155,7 +149,6 @@ static struct target_type error_target = {
 	.map  = io_err_map,
 	.clone_and_map_rq = io_err_clone_and_map_rq,
 	.release_clone_rq = io_err_release_clone_rq,
-	.direct_access = io_err_dax_direct_access,
 };
 
 int __init dm_target_init(void)
-- 
2.14.3