[stable-4.14 0/3] some backport for stable

[stable-4.14 0/3] some backport for stable

[Jack Wang]

Hi Greg, hi Sasha,

Please consider following backport for next stable release.

First patch for vhost_net has been tested with our in house regression tests
with VM migration with kernel 4.14.171, but should be also applied to older
stable tree.

mce patch is to fix a call trace in EPYC Rome server during boot.

EDAC one is to fix a regression backported to at least 4.14 and 4.19, should be
applied to both tree, kernel 5.4/5.5 already have the patch.

Regards,
Jack Wang from IONOS SE.

Eugenio Pérez (1):
  vhost: Check docket sk_family instead of call getname

Yazen Ghannam (2):
  x86/mce: Handle varying MCA bank counts
  EDAC/amd64: Set grain per DIMM

 arch/x86/kernel/cpu/mcheck/mce-inject.c | 14 +++++++-------
 arch/x86/kernel/cpu/mcheck/mce.c        | 22 +++++++---------------
 drivers/edac/amd64_edac.c               |  1 +
 drivers/vhost/net.c                     | 13 ++-----------
 4 files changed, 17 insertions(+), 33 deletions(-)

-- 
2.17.1

[stable-4.14 1/3] vhost: Check docket sk_family instead of call getname

[Jack Wang]

From: Eugenio Pérez <eperezma@redhat.com>

commit 42d84c8490f9f0931786f1623191fcab397c3d64 upstream.

Doing so, we save one call to get data we already have in the struct.

Also, since there is no guarantee that getname use sockaddr_ll
parameter beyond its size, we add a little bit of security here.
It should do not do beyond MAX_ADDR_LEN, but syzbot found that
ax25_getname writes more (72 bytes, the size of full_sockaddr_ax25,
versus 20 + 32 bytes of sockaddr_ll + MAX_ADDR_LEN in syzbot repro).

Fixes: 3a4d5c94e9593 ("vhost_net: a kernel-level virtio server")
Reported-by: syzbot+f2a62d07a5198c819c7b@syzkaller.appspotmail.com
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[jwang: backport to 4.14]
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
---
 drivers/vhost/net.c | 13 ++-----------
 1 file changed, 2 insertions(+), 11 deletions(-)

diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index 4d11152e60c1..8fe07622ae59 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -1025,11 +1025,7 @@ static int vhost_net_release(struct inode *inode, struct file *f)
 
 static struct socket *get_raw_socket(int fd)
 {
-	struct {
-		struct sockaddr_ll sa;
-		char  buf[MAX_ADDR_LEN];
-	} uaddr;
-	int uaddr_len = sizeof uaddr, r;
+	int r;
 	struct socket *sock = sockfd_lookup(fd, &r);
 
 	if (!sock)
@@ -1041,12 +1037,7 @@ static struct socket *get_raw_socket(int fd)
 		goto err;
 	}
 
-	r = sock->ops->getname(sock, (struct sockaddr *)&uaddr.sa,
-			       &uaddr_len, 0);
-	if (r)
-		goto err;
-
-	if (uaddr.sa.sll_family != AF_PACKET) {
+	if (sock->sk->sk_family != AF_PACKET) {
 		r = -EPFNOSUPPORT;
 		goto err;
 	}
-- 
2.17.1

[stable-4.14 2/3] x86/mce: Handle varying MCA bank counts

[Jack Wang]

From: Yazen Ghannam <yazen.ghannam@amd.com>

[ Upstream commit 006c077041dc73b9490fffc4c6af5befe0687110 ]

Linux reads MCG_CAP[Count] to find the number of MCA banks visible to a
CPU. Currently, this number is the same for all CPUs and a warning is
shown if there is a difference. The number of banks is overwritten with
the MCG_CAP[Count] value of each following CPU that boots.

According to the Intel SDM and AMD APM, the MCG_CAP[Count] value gives
the number of banks that are available to a "processor implementation".
The AMD BKDGs/PPRs further clarify that this value is per core. This
value has historically been the same for every core in the system, but
that is not an architectural requirement.

Future AMD systems may have different MCG_CAP[Count] values per core,
so the assumption that all CPUs will have the same MCG_CAP[Count] value
will no longer be valid.

Also, the first CPU to boot will allocate the struct mce_banks[] array
using the number of banks based on its MCG_CAP[Count] value. The machine
check handler and other functions use the global number of banks to
iterate and index into the mce_banks[] array. So it's possible to use an
out-of-bounds index on an asymmetric system where a following CPU sees a
MCG_CAP[Count] value greater than its predecessors.

Thus, allocate the mce_banks[] array to the maximum number of banks.
This will avoid the potential out-of-bounds index since the value of
mca_cfg.banks is capped to MAX_NR_BANKS.

Set the value of mca_cfg.banks equal to the max of the previous value
and the value for the current CPU. This way mca_cfg.banks will always
represent the max number of banks detected on any CPU in the system.

This will ensure that all CPUs will access all the banks that are
visible to them. A CPU that can access fewer than the max number of
banks will find the registers of the extra banks to be read-as-zero.

Furthermore, print the resulting number of MCA banks in use. Do this in
mcheck_late_init() so that the final value is printed after all CPUs
have been initialized.

Finally, get bank count from target CPU when doing injection with mce-inject
module.

 [ bp: Remove out-of-bounds example, passify and cleanup commit message. ]

Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: Pu Wen <puwen@hygon.cn>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20180727214009.78289-1-Yazen.Ghannam@amd.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[jwang: cherry-pick to fix boot warning in
arch/x86/kernel/cpu/mcheck/mce.c:1549 in epyc rome server]
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
---
 arch/x86/kernel/cpu/mcheck/mce-inject.c | 14 +++++++-------
 arch/x86/kernel/cpu/mcheck/mce.c        | 22 +++++++---------------
 2 files changed, 14 insertions(+), 22 deletions(-)

diff --git a/arch/x86/kernel/cpu/mcheck/mce-inject.c b/arch/x86/kernel/cpu/mcheck/mce-inject.c
index f12141ba9a76..e57b59762f9f 100644
--- a/arch/x86/kernel/cpu/mcheck/mce-inject.c
+++ b/arch/x86/kernel/cpu/mcheck/mce-inject.c
@@ -46,8 +46,6 @@
 static struct mce i_mce;
 static struct dentry *dfs_inj;
 
-static u8 n_banks;
-
 #define MAX_FLAG_OPT_SIZE	4
 #define NBCFG			0x44
 
@@ -570,9 +568,15 @@ static void do_inject(void)
 static int inj_bank_set(void *data, u64 val)
 {
 	struct mce *m = (struct mce *)data;
+	u8 n_banks;
+	u64 cap;
+
+	/* Get bank count on target CPU so we can handle non-uniform values. */
+	rdmsrl_on_cpu(m->extcpu, MSR_IA32_MCG_CAP, &cap);
+	n_banks = cap & MCG_BANKCNT_MASK;
 
 	if (val >= n_banks) {
-		pr_err("Non-existent MCE bank: %llu\n", val);
+		pr_err("MCA bank %llu non-existent on CPU%d\n", val, m->extcpu);
 		return -EINVAL;
 	}
 
@@ -665,10 +669,6 @@ static struct dfs_node {
 static int __init debugfs_init(void)
 {
 	unsigned int i;
-	u64 cap;
-
-	rdmsrl(MSR_IA32_MCG_CAP, cap);
-	n_banks = cap & MCG_BANKCNT_MASK;
 
 	dfs_inj = debugfs_create_dir("mce-inject", NULL);
 	if (!dfs_inj)
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index 0b0e44f85393..95c09db1bba2 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -1499,13 +1499,12 @@ EXPORT_SYMBOL_GPL(mce_notify_irq);
 static int __mcheck_cpu_mce_banks_init(void)
 {
 	int i;
-	u8 num_banks = mca_cfg.banks;
 
-	mce_banks = kzalloc(num_banks * sizeof(struct mce_bank), GFP_KERNEL);
+	mce_banks = kcalloc(MAX_NR_BANKS, sizeof(struct mce_bank), GFP_KERNEL);
 	if (!mce_banks)
 		return -ENOMEM;
 
-	for (i = 0; i < num_banks; i++) {
+	for (i = 0; i < MAX_NR_BANKS; i++) {
 		struct mce_bank *b = &mce_banks[i];
 
 		b->ctl = -1ULL;
@@ -1519,28 +1518,19 @@ static int __mcheck_cpu_mce_banks_init(void)
  */
 static int __mcheck_cpu_cap_init(void)
 {
-	unsigned b;
 	u64 cap;
+	u8 b;
 
 	rdmsrl(MSR_IA32_MCG_CAP, cap);
 
 	b = cap & MCG_BANKCNT_MASK;
-	if (!mca_cfg.banks)
-		pr_info("CPU supports %d MCE banks\n", b);
-
-	if (b > MAX_NR_BANKS) {
-		pr_warn("Using only %u machine check banks out of %u\n",
-			MAX_NR_BANKS, b);
+	if (WARN_ON_ONCE(b > MAX_NR_BANKS))
 		b = MAX_NR_BANKS;
-	}
 
-	/* Don't support asymmetric configurations today */
-	WARN_ON(mca_cfg.banks != 0 && b != mca_cfg.banks);
-	mca_cfg.banks = b;
+	mca_cfg.banks = max(mca_cfg.banks, b);
 
 	if (!mce_banks) {
 		int err = __mcheck_cpu_mce_banks_init();
-
 		if (err)
 			return err;
 	}
@@ -2470,6 +2460,8 @@ EXPORT_SYMBOL_GPL(mcsafe_key);
 
 static int __init mcheck_late_init(void)
 {
+	pr_info("Using %d MCE banks\n", mca_cfg.banks);
+
 	if (mca_cfg.recovery)
 		static_branch_inc(&mcsafe_key);
 
-- 
2.17.1

[stable-4.14 3/3] EDAC/amd64: Set grain per DIMM

[Jack Wang]

From: Yazen Ghannam <yazen.ghannam@amd.com>

[ Upstream commit 466503d6b1b33be46ab87c6090f0ade6c6011cbc ]

The following commit introduced a warning on error reports without a
non-zero grain value.

  3724ace582d9 ("EDAC/mc: Fix grain_bits calculation")

The amd64_edac_mod module does not provide a value, so the warning will
be given on the first reported memory error.

Set the grain per DIMM to cacheline size (64 bytes). This is the current
recommendation.

Fixes: 3724ace582d9 ("EDAC/mc: Fix grain_bits calculation")
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "linux-edac@vger.kernel.org" <linux-edac@vger.kernel.org>
Cc: James Morse <james.morse@arm.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Robert Richter <rrichter@marvell.com>
Cc: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20191022203448.13962-7-Yazen.Ghannam@amd.com
[jwang: backport to 4.14 for fix warning during memory error. ]
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
---
 drivers/edac/amd64_edac.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c
index 40fb0e7ff8fd..b36abd253786 100644
--- a/drivers/edac/amd64_edac.c
+++ b/drivers/edac/amd64_edac.c
@@ -2863,6 +2863,7 @@ static int init_csrows(struct mem_ctl_info *mci)
 			dimm = csrow->channels[j]->dimm;
 			dimm->mtype = pvt->dram_type;
 			dimm->edac_mode = edac_mode;
+			dimm->grain = 64;
 		}
 	}
 
-- 
2.17.1

Re: [stable-4.14 0/3] some backport for stable

[Sasha Levin]

On Thu, Mar 05, 2020 at 05:30:04PM +0100, Jack Wang wrote:
>Hi Greg, hi Sasha,
>
>Please consider following backport for next stable release.
>
>First patch for vhost_net has been tested with our in house regression tests
>with VM migration with kernel 4.14.171, but should be also applied to older
>stable tree.
>
>mce patch is to fix a call trace in EPYC Rome server during boot.
>
>EDAC one is to fix a regression backported to at least 4.14 and 4.19, should be
>applied to both tree, kernel 5.4/5.5 already have the patch.
>
>Regards,
>Jack Wang from IONOS SE.
>
>Eugenio Pérez (1):
>  vhost: Check docket sk_family instead of call getname
>
>Yazen Ghannam (2):
>  x86/mce: Handle varying MCA bank counts
>  EDAC/amd64: Set grain per DIMM
>
> arch/x86/kernel/cpu/mcheck/mce-inject.c | 14 +++++++-------
> arch/x86/kernel/cpu/mcheck/mce.c        | 22 +++++++---------------
> drivers/edac/amd64_edac.c               |  1 +
> drivers/vhost/net.c                     | 13 ++-----------
> 4 files changed, 17 insertions(+), 33 deletions(-)

Queued up. I took the EDAC commit to 4.19 as well.

-- 
Thanks,
Sasha