All of lore.kernel.org
 help / color / mirror / Atom feed
From: Claire Chang <tientzu@chromium.org>
To: Rob Herring <robh+dt@kernel.org>,
	mpe@ellerman.id.au, Joerg Roedel <joro@8bytes.org>,
	Will Deacon <will@kernel.org>,
	Frank Rowand <frowand.list@gmail.com>,
	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
	boris.ostrovsky@oracle.com, jgross@suse.com,
	Christoph Hellwig <hch@lst.de>,
	Marek Szyprowski <m.szyprowski@samsung.com>
Cc: benh@kernel.crashing.org, paulus@samba.org,
	"list@263.net:IOMMU DRIVERS" <iommu@lists.linux-foundation.org>,
	sstabellini@kernel.org, Robin Murphy <robin.murphy@arm.com>,
	grant.likely@arm.com, xypron.glpk@gmx.de,
	Thierry Reding <treding@nvidia.com>,
	mingo@kernel.org, bauerman@linux.ibm.com, peterz@infradead.org,
	Greg KH <gregkh@linuxfoundation.org>,
	Saravana Kannan <saravanak@google.com>,
	"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
	heikki.krogerus@linux.intel.com,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Randy Dunlap <rdunlap@infradead.org>,
	Dan Williams <dan.j.williams@intel.com>,
	Bartosz Golaszewski <bgolaszewski@baylibre.com>,
	linux-devicetree <devicetree@vger.kernel.org>,
	lkml <linux-kernel@vger.kernel.org>,
	linuxppc-dev@lists.ozlabs.org, xen-devel@lists.xenproject.org,
	Nicolas Boichat <drinkcat@chromium.org>,
	Jim Quinlan <james.quinlan@broadcom.com>,
	tfiga@chromium.org, bskeggs@redhat.com, bhelgaas@google.com,
	chris@chris-wilson.co.uk, tientzu@chromium.org, daniel@ffwll.ch,
	airlied@linux.ie, dri-devel@lists.freedesktop.org,
	intel-gfx@lists.freedesktop.org, jani.nikula@linux.intel.com,
	jxgao@google.com, joonas.lahtinen@linux.intel.com,
	linux-pci@vger.kernel.org, maarten.lankhorst@linux.intel.com,
	matthew.auld@intel.com, rodrigo.vivi@intel.com,
	thomas.hellstrom@linux.intel.com
Subject: [PATCH v9 07/14] swiotlb: Bounce data from/to restricted DMA pool if available
Date: Fri, 11 Jun 2021 23:26:52 +0800	[thread overview]
Message-ID: <20210611152659.2142983-8-tientzu@chromium.org> (raw)
In-Reply-To: <20210611152659.2142983-1-tientzu@chromium.org>

Regardless of swiotlb setting, the restricted DMA pool is preferred if
available.

The restricted DMA pools provide a basic level of protection against the
DMA overwriting buffer contents at unexpected times. However, to protect
against general data leakage and system memory corruption, the system
needs to provide a way to lock down the memory access, e.g., MPU.

Note that is_dev_swiotlb_force doesn't check if
swiotlb_force == SWIOTLB_FORCE. Otherwise the memory allocation behavior
with default swiotlb will be changed by the following patche
("dma-direct: Allocate memory from restricted DMA pool if available").

Signed-off-by: Claire Chang <tientzu@chromium.org>
---
 include/linux/swiotlb.h | 10 +++++++++-
 kernel/dma/direct.c     |  3 ++-
 kernel/dma/direct.h     |  3 ++-
 kernel/dma/swiotlb.c    |  1 +
 4 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 06cf17a80f5c..8200c100fe10 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -85,6 +85,7 @@ extern enum swiotlb_force swiotlb_force;
  *		unmap calls.
  * @debugfs:	The dentry to debugfs.
  * @late_alloc:	%true if allocated using the page allocator
+ * @force_swiotlb: %true if swiotlb is forced
  */
 struct io_tlb_mem {
 	phys_addr_t start;
@@ -95,6 +96,7 @@ struct io_tlb_mem {
 	spinlock_t lock;
 	struct dentry *debugfs;
 	bool late_alloc;
+	bool force_swiotlb;
 	struct io_tlb_slot {
 		phys_addr_t orig_addr;
 		size_t alloc_size;
@@ -115,6 +117,11 @@ static inline void swiotlb_set_io_tlb_default_mem(struct device *dev)
 	dev->dma_io_tlb_mem = io_tlb_default_mem;
 }
 
+static inline bool is_dev_swiotlb_force(struct device *dev)
+{
+	return dev->dma_io_tlb_mem->force_swiotlb;
+}
+
 void __init swiotlb_exit(void);
 unsigned int swiotlb_max_segment(void);
 size_t swiotlb_max_mapping_size(struct device *dev);
@@ -126,8 +133,9 @@ static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
 {
 	return false;
 }
-static inline void swiotlb_set_io_tlb_default_mem(struct device *dev)
+static inline bool is_dev_swiotlb_force(struct device *dev)
 {
+	return false;
 }
 static inline void swiotlb_exit(void)
 {
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 7a88c34d0867..078f7087e466 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -496,7 +496,8 @@ size_t dma_direct_max_mapping_size(struct device *dev)
 {
 	/* If SWIOTLB is active, use its maximum mapping size */
 	if (is_swiotlb_active(dev) &&
-	    (dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE))
+	    (dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE ||
+	     is_dev_swiotlb_force(dev)))
 		return swiotlb_max_mapping_size(dev);
 	return SIZE_MAX;
 }
diff --git a/kernel/dma/direct.h b/kernel/dma/direct.h
index 13e9e7158d94..f94813674e23 100644
--- a/kernel/dma/direct.h
+++ b/kernel/dma/direct.h
@@ -87,7 +87,8 @@ static inline dma_addr_t dma_direct_map_page(struct device *dev,
 	phys_addr_t phys = page_to_phys(page) + offset;
 	dma_addr_t dma_addr = phys_to_dma(dev, phys);
 
-	if (unlikely(swiotlb_force == SWIOTLB_FORCE))
+	if (unlikely(swiotlb_force == SWIOTLB_FORCE) ||
+	    is_dev_swiotlb_force(dev))
 		return swiotlb_map(dev, phys, size, dir, attrs);
 
 	if (unlikely(!dma_capable(dev, dma_addr, size, true))) {
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 21e99907edd6..e5ccc198d0a7 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -714,6 +714,7 @@ static int rmem_swiotlb_device_init(struct reserved_mem *rmem,
 			return -ENOMEM;
 
 		swiotlb_init_io_tlb_mem(mem, rmem->base, nslabs, false, true);
+		mem->force_swiotlb = true;
 
 		rmem->priv = mem;
 
-- 
2.32.0.272.g935e593368-goog


WARNING: multiple messages have this Message-ID
From: Claire Chang <tientzu@chromium.org>
To: Rob Herring <robh+dt@kernel.org>,
	mpe@ellerman.id.au, Joerg Roedel <joro@8bytes.org>,
	Will Deacon <will@kernel.org>,
	Frank Rowand <frowand.list@gmail.com>,
	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
	boris.ostrovsky@oracle.com, jgross@suse.com,
	Christoph Hellwig <hch@lst.de>,
	Marek Szyprowski <m.szyprowski@samsung.com>
Cc: heikki.krogerus@linux.intel.com,
	thomas.hellstrom@linux.intel.com, peterz@infradead.org,
	joonas.lahtinen@linux.intel.com, dri-devel@lists.freedesktop.org,
	chris@chris-wilson.co.uk, grant.likely@arm.com, paulus@samba.org,
	mingo@kernel.org, jxgao@google.com, sstabellini@kernel.org,
	Saravana Kannan <saravanak@google.com>,
	xypron.glpk@gmx.de,
	"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
	Bartosz Golaszewski <bgolaszewski@baylibre.com>,
	bskeggs@redhat.com, linux-pci@vger.kernel.org,
	xen-devel@lists.xenproject.org,
	Thierry Reding <treding@nvidia.com>,
	intel-gfx@lists.freedesktop.org, matthew.auld@intel.com,
	linux-devicetree <devicetree@vger.kernel.org>,
	daniel@ffwll.ch, airlied@linux.ie,
	maarten.lankhorst@linux.intel.com, linuxppc-dev@lists.ozlabs.org,
	jani.nikula@linux.intel.com,
	Nicolas Boichat <drinkcat@chromium.org>,
	rodrigo.vivi@intel.com, bhelgaas@google.com,
	tientzu@chromium.org, Dan Williams <dan.j.williams@intel.com>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Greg KH <gregkh@linuxfoundation.org>,
	Randy Dunlap <rdunlap@infradead.org>,
	lkml <linux-kernel@vger.kernel.org>,
	tfiga@chromium.org,
	"list@263.net:IOMMU DRIVERS" <iommu@lists.linux-foundation.org>,
	Jim Quinlan <james.quinlan@broadcom.com>,
	Robin Murphy <robin.murphy@arm.com>,
	bauerman@linux.ibm.com
Subject: [PATCH v9 07/14] swiotlb: Bounce data from/to restricted DMA pool if available
Date: Fri, 11 Jun 2021 23:26:52 +0800	[thread overview]
Message-ID: <20210611152659.2142983-8-tientzu@chromium.org> (raw)
In-Reply-To: <20210611152659.2142983-1-tientzu@chromium.org>

Regardless of swiotlb setting, the restricted DMA pool is preferred if
available.

The restricted DMA pools provide a basic level of protection against the
DMA overwriting buffer contents at unexpected times. However, to protect
against general data leakage and system memory corruption, the system
needs to provide a way to lock down the memory access, e.g., MPU.

Note that is_dev_swiotlb_force doesn't check if
swiotlb_force == SWIOTLB_FORCE. Otherwise the memory allocation behavior
with default swiotlb will be changed by the following patche
("dma-direct: Allocate memory from restricted DMA pool if available").

Signed-off-by: Claire Chang <tientzu@chromium.org>
---
 include/linux/swiotlb.h | 10 +++++++++-
 kernel/dma/direct.c     |  3 ++-
 kernel/dma/direct.h     |  3 ++-
 kernel/dma/swiotlb.c    |  1 +
 4 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 06cf17a80f5c..8200c100fe10 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -85,6 +85,7 @@ extern enum swiotlb_force swiotlb_force;
  *		unmap calls.
  * @debugfs:	The dentry to debugfs.
  * @late_alloc:	%true if allocated using the page allocator
+ * @force_swiotlb: %true if swiotlb is forced
  */
 struct io_tlb_mem {
 	phys_addr_t start;
@@ -95,6 +96,7 @@ struct io_tlb_mem {
 	spinlock_t lock;
 	struct dentry *debugfs;
 	bool late_alloc;
+	bool force_swiotlb;
 	struct io_tlb_slot {
 		phys_addr_t orig_addr;
 		size_t alloc_size;
@@ -115,6 +117,11 @@ static inline void swiotlb_set_io_tlb_default_mem(struct device *dev)
 	dev->dma_io_tlb_mem = io_tlb_default_mem;
 }
 
+static inline bool is_dev_swiotlb_force(struct device *dev)
+{
+	return dev->dma_io_tlb_mem->force_swiotlb;
+}
+
 void __init swiotlb_exit(void);
 unsigned int swiotlb_max_segment(void);
 size_t swiotlb_max_mapping_size(struct device *dev);
@@ -126,8 +133,9 @@ static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
 {
 	return false;
 }
-static inline void swiotlb_set_io_tlb_default_mem(struct device *dev)
+static inline bool is_dev_swiotlb_force(struct device *dev)
 {
+	return false;
 }
 static inline void swiotlb_exit(void)
 {
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 7a88c34d0867..078f7087e466 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -496,7 +496,8 @@ size_t dma_direct_max_mapping_size(struct device *dev)
 {
 	/* If SWIOTLB is active, use its maximum mapping size */
 	if (is_swiotlb_active(dev) &&
-	    (dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE))
+	    (dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE ||
+	     is_dev_swiotlb_force(dev)))
 		return swiotlb_max_mapping_size(dev);
 	return SIZE_MAX;
 }
diff --git a/kernel/dma/direct.h b/kernel/dma/direct.h
index 13e9e7158d94..f94813674e23 100644
--- a/kernel/dma/direct.h
+++ b/kernel/dma/direct.h
@@ -87,7 +87,8 @@ static inline dma_addr_t dma_direct_map_page(struct device *dev,
 	phys_addr_t phys = page_to_phys(page) + offset;
 	dma_addr_t dma_addr = phys_to_dma(dev, phys);
 
-	if (unlikely(swiotlb_force == SWIOTLB_FORCE))
+	if (unlikely(swiotlb_force == SWIOTLB_FORCE) ||
+	    is_dev_swiotlb_force(dev))
 		return swiotlb_map(dev, phys, size, dir, attrs);
 
 	if (unlikely(!dma_capable(dev, dma_addr, size, true))) {
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 21e99907edd6..e5ccc198d0a7 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -714,6 +714,7 @@ static int rmem_swiotlb_device_init(struct reserved_mem *rmem,
 			return -ENOMEM;
 
 		swiotlb_init_io_tlb_mem(mem, rmem->base, nslabs, false, true);
+		mem->force_swiotlb = true;
 
 		rmem->priv = mem;
 
-- 
2.32.0.272.g935e593368-goog


WARNING: multiple messages have this Message-ID
From: Claire Chang <tientzu@chromium.org>
To: Rob Herring <robh+dt@kernel.org>,
	mpe@ellerman.id.au, Joerg Roedel <joro@8bytes.org>,
	Will Deacon <will@kernel.org>,
	Frank Rowand <frowand.list@gmail.com>,
	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
	boris.ostrovsky@oracle.com, jgross@suse.com,
	Christoph Hellwig <hch@lst.de>,
	Marek Szyprowski <m.szyprowski@samsung.com>
Cc: heikki.krogerus@linux.intel.com,
	thomas.hellstrom@linux.intel.com, peterz@infradead.org,
	benh@kernel.crashing.org, joonas.lahtinen@linux.intel.com,
	dri-devel@lists.freedesktop.org, chris@chris-wilson.co.uk,
	grant.likely@arm.com, paulus@samba.org, mingo@kernel.org,
	jxgao@google.com, sstabellini@kernel.org,
	Saravana Kannan <saravanak@google.com>,
	xypron.glpk@gmx.de,
	"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
	Bartosz Golaszewski <bgolaszewski@baylibre.com>,
	bskeggs@redhat.com, linux-pci@vger.kernel.org,
	xen-devel@lists.xenproject.org,
	Thierry Reding <treding@nvidia.com>,
	intel-gfx@lists.freedesktop.org, matthew.auld@intel.com,
	linux-devicetree <devicetree@vger.kernel.org>,
	daniel@ffwll.ch, airlied@linux.ie,
	maarten.lankhorst@linux.intel.com, linuxppc-dev@lists.ozlabs.org,
	jani.nikula@linux.intel.com,
	Nicolas Boichat <drinkcat@chromium.org>,
	rodrigo.vivi@intel.com, bhelgaas@google.com,
	tientzu@chromium.org, Dan Williams <dan.j.williams@intel.com>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Greg KH <gregkh@linuxfoundation.org>,
	Randy Dunlap <rdunlap@infradead.org>,
	lkml <linux-kernel@vger.kernel.org>,
	"list@263.net:IOMMU DRIVERS" <iommu@lists.linux-foundation.org>,
	Jim Quinlan <james.quinlan@broadcom.com>,
	Robin Murphy <robin.murphy@arm.com>,
	bauerman@linux.ibm.com
Subject: [PATCH v9 07/14] swiotlb: Bounce data from/to restricted DMA pool if available
Date: Fri, 11 Jun 2021 23:26:52 +0800	[thread overview]
Message-ID: <20210611152659.2142983-8-tientzu@chromium.org> (raw)
In-Reply-To: <20210611152659.2142983-1-tientzu@chromium.org>

Regardless of swiotlb setting, the restricted DMA pool is preferred if
available.

The restricted DMA pools provide a basic level of protection against the
DMA overwriting buffer contents at unexpected times. However, to protect
against general data leakage and system memory corruption, the system
needs to provide a way to lock down the memory access, e.g., MPU.

Note that is_dev_swiotlb_force doesn't check if
swiotlb_force == SWIOTLB_FORCE. Otherwise the memory allocation behavior
with default swiotlb will be changed by the following patche
("dma-direct: Allocate memory from restricted DMA pool if available").

Signed-off-by: Claire Chang <tientzu@chromium.org>
---
 include/linux/swiotlb.h | 10 +++++++++-
 kernel/dma/direct.c     |  3 ++-
 kernel/dma/direct.h     |  3 ++-
 kernel/dma/swiotlb.c    |  1 +
 4 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 06cf17a80f5c..8200c100fe10 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -85,6 +85,7 @@ extern enum swiotlb_force swiotlb_force;
  *		unmap calls.
  * @debugfs:	The dentry to debugfs.
  * @late_alloc:	%true if allocated using the page allocator
+ * @force_swiotlb: %true if swiotlb is forced
  */
 struct io_tlb_mem {
 	phys_addr_t start;
@@ -95,6 +96,7 @@ struct io_tlb_mem {
 	spinlock_t lock;
 	struct dentry *debugfs;
 	bool late_alloc;
+	bool force_swiotlb;
 	struct io_tlb_slot {
 		phys_addr_t orig_addr;
 		size_t alloc_size;
@@ -115,6 +117,11 @@ static inline void swiotlb_set_io_tlb_default_mem(struct device *dev)
 	dev->dma_io_tlb_mem = io_tlb_default_mem;
 }
 
+static inline bool is_dev_swiotlb_force(struct device *dev)
+{
+	return dev->dma_io_tlb_mem->force_swiotlb;
+}
+
 void __init swiotlb_exit(void);
 unsigned int swiotlb_max_segment(void);
 size_t swiotlb_max_mapping_size(struct device *dev);
@@ -126,8 +133,9 @@ static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
 {
 	return false;
 }
-static inline void swiotlb_set_io_tlb_default_mem(struct device *dev)
+static inline bool is_dev_swiotlb_force(struct device *dev)
 {
+	return false;
 }
 static inline void swiotlb_exit(void)
 {
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 7a88c34d0867..078f7087e466 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -496,7 +496,8 @@ size_t dma_direct_max_mapping_size(struct device *dev)
 {
 	/* If SWIOTLB is active, use its maximum mapping size */
 	if (is_swiotlb_active(dev) &&
-	    (dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE))
+	    (dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE ||
+	     is_dev_swiotlb_force(dev)))
 		return swiotlb_max_mapping_size(dev);
 	return SIZE_MAX;
 }
diff --git a/kernel/dma/direct.h b/kernel/dma/direct.h
index 13e9e7158d94..f94813674e23 100644
--- a/kernel/dma/direct.h
+++ b/kernel/dma/direct.h
@@ -87,7 +87,8 @@ static inline dma_addr_t dma_direct_map_page(struct device *dev,
 	phys_addr_t phys = page_to_phys(page) + offset;
 	dma_addr_t dma_addr = phys_to_dma(dev, phys);
 
-	if (unlikely(swiotlb_force == SWIOTLB_FORCE))
+	if (unlikely(swiotlb_force == SWIOTLB_FORCE) ||
+	    is_dev_swiotlb_force(dev))
 		return swiotlb_map(dev, phys, size, dir, attrs);
 
 	if (unlikely(!dma_capable(dev, dma_addr, size, true))) {
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 21e99907edd6..e5ccc198d0a7 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -714,6 +714,7 @@ static int rmem_swiotlb_device_init(struct reserved_mem *rmem,
 			return -ENOMEM;
 
 		swiotlb_init_io_tlb_mem(mem, rmem->base, nslabs, false, true);
+		mem->force_swiotlb = true;
 
 		rmem->priv = mem;
 
-- 
2.32.0.272.g935e593368-goog

_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

WARNING: multiple messages have this Message-ID
From: Claire Chang <tientzu@chromium.org>
To: Rob Herring <robh+dt@kernel.org>,
	mpe@ellerman.id.au, Joerg Roedel <joro@8bytes.org>,
	Will Deacon <will@kernel.org>,
	Frank Rowand <frowand.list@gmail.com>,
	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
	boris.ostrovsky@oracle.com, jgross@suse.com,
	Christoph Hellwig <hch@lst.de>,
	Marek Szyprowski <m.szyprowski@samsung.com>
Cc: heikki.krogerus@linux.intel.com,
	thomas.hellstrom@linux.intel.com, peterz@infradead.org,
	dri-devel@lists.freedesktop.org, chris@chris-wilson.co.uk,
	grant.likely@arm.com, paulus@samba.org, mingo@kernel.org,
	jxgao@google.com, sstabellini@kernel.org,
	Saravana Kannan <saravanak@google.com>,
	xypron.glpk@gmx.de,
	"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
	Bartosz Golaszewski <bgolaszewski@baylibre.com>,
	bskeggs@redhat.com, linux-pci@vger.kernel.org,
	xen-devel@lists.xenproject.org,
	Thierry Reding <treding@nvidia.com>,
	intel-gfx@lists.freedesktop.org, matthew.auld@intel.com,
	linux-devicetree <devicetree@vger.kernel.org>,
	airlied@linux.ie, Robin Murphy <robin.murphy@arm.com>,
	Nicolas Boichat <drinkcat@chromium.org>,
	rodrigo.vivi@intel.com, bhelgaas@google.com,
	tientzu@chromium.org, Dan Williams <dan.j.williams@intel.com>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Greg KH <gregkh@linuxfoundation.org>,
	Randy Dunlap <rdunlap@infradead.org>,
	lkml <linux-kernel@vger.kernel.org>,
	tfiga@chromium.org,
	"list@263.net:IOMMU DRIVERS" <iommu@lists.linux-foundation.org>,
	Jim Quinlan <james.quinlan@broadcom.com>,
	linuxppc-dev@lists.ozlabs.org, bauerman@linux.ibm.com
Subject: [PATCH v9 07/14] swiotlb: Bounce data from/to restricted DMA pool if available
Date: Fri, 11 Jun 2021 23:26:52 +0800	[thread overview]
Message-ID: <20210611152659.2142983-8-tientzu@chromium.org> (raw)
In-Reply-To: <20210611152659.2142983-1-tientzu@chromium.org>

Regardless of swiotlb setting, the restricted DMA pool is preferred if
available.

The restricted DMA pools provide a basic level of protection against the
DMA overwriting buffer contents at unexpected times. However, to protect
against general data leakage and system memory corruption, the system
needs to provide a way to lock down the memory access, e.g., MPU.

Note that is_dev_swiotlb_force doesn't check if
swiotlb_force == SWIOTLB_FORCE. Otherwise the memory allocation behavior
with default swiotlb will be changed by the following patche
("dma-direct: Allocate memory from restricted DMA pool if available").

Signed-off-by: Claire Chang <tientzu@chromium.org>
---
 include/linux/swiotlb.h | 10 +++++++++-
 kernel/dma/direct.c     |  3 ++-
 kernel/dma/direct.h     |  3 ++-
 kernel/dma/swiotlb.c    |  1 +
 4 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 06cf17a80f5c..8200c100fe10 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -85,6 +85,7 @@ extern enum swiotlb_force swiotlb_force;
  *		unmap calls.
  * @debugfs:	The dentry to debugfs.
  * @late_alloc:	%true if allocated using the page allocator
+ * @force_swiotlb: %true if swiotlb is forced
  */
 struct io_tlb_mem {
 	phys_addr_t start;
@@ -95,6 +96,7 @@ struct io_tlb_mem {
 	spinlock_t lock;
 	struct dentry *debugfs;
 	bool late_alloc;
+	bool force_swiotlb;
 	struct io_tlb_slot {
 		phys_addr_t orig_addr;
 		size_t alloc_size;
@@ -115,6 +117,11 @@ static inline void swiotlb_set_io_tlb_default_mem(struct device *dev)
 	dev->dma_io_tlb_mem = io_tlb_default_mem;
 }
 
+static inline bool is_dev_swiotlb_force(struct device *dev)
+{
+	return dev->dma_io_tlb_mem->force_swiotlb;
+}
+
 void __init swiotlb_exit(void);
 unsigned int swiotlb_max_segment(void);
 size_t swiotlb_max_mapping_size(struct device *dev);
@@ -126,8 +133,9 @@ static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
 {
 	return false;
 }
-static inline void swiotlb_set_io_tlb_default_mem(struct device *dev)
+static inline bool is_dev_swiotlb_force(struct device *dev)
 {
+	return false;
 }
 static inline void swiotlb_exit(void)
 {
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 7a88c34d0867..078f7087e466 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -496,7 +496,8 @@ size_t dma_direct_max_mapping_size(struct device *dev)
 {
 	/* If SWIOTLB is active, use its maximum mapping size */
 	if (is_swiotlb_active(dev) &&
-	    (dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE))
+	    (dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE ||
+	     is_dev_swiotlb_force(dev)))
 		return swiotlb_max_mapping_size(dev);
 	return SIZE_MAX;
 }
diff --git a/kernel/dma/direct.h b/kernel/dma/direct.h
index 13e9e7158d94..f94813674e23 100644
--- a/kernel/dma/direct.h
+++ b/kernel/dma/direct.h
@@ -87,7 +87,8 @@ static inline dma_addr_t dma_direct_map_page(struct device *dev,
 	phys_addr_t phys = page_to_phys(page) + offset;
 	dma_addr_t dma_addr = phys_to_dma(dev, phys);
 
-	if (unlikely(swiotlb_force == SWIOTLB_FORCE))
+	if (unlikely(swiotlb_force == SWIOTLB_FORCE) ||
+	    is_dev_swiotlb_force(dev))
 		return swiotlb_map(dev, phys, size, dir, attrs);
 
 	if (unlikely(!dma_capable(dev, dma_addr, size, true))) {
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 21e99907edd6..e5ccc198d0a7 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -714,6 +714,7 @@ static int rmem_swiotlb_device_init(struct reserved_mem *rmem,
 			return -ENOMEM;
 
 		swiotlb_init_io_tlb_mem(mem, rmem->base, nslabs, false, true);
+		mem->force_swiotlb = true;
 
 		rmem->priv = mem;
 
-- 
2.32.0.272.g935e593368-goog


WARNING: multiple messages have this Message-ID
From: Claire Chang <tientzu@chromium.org>
To: Rob Herring <robh+dt@kernel.org>,
	mpe@ellerman.id.au, Joerg Roedel <joro@8bytes.org>,
	Will Deacon <will@kernel.org>,
	Frank Rowand <frowand.list@gmail.com>,
	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
	boris.ostrovsky@oracle.com, jgross@suse.com,
	Christoph Hellwig <hch@lst.de>,
	Marek Szyprowski <m.szyprowski@samsung.com>
Cc: heikki.krogerus@linux.intel.com,
	thomas.hellstrom@linux.intel.com, peterz@infradead.org,
	benh@kernel.crashing.org, dri-devel@lists.freedesktop.org,
	chris@chris-wilson.co.uk, grant.likely@arm.com, paulus@samba.org,
	mingo@kernel.org, jxgao@google.com, sstabellini@kernel.org,
	Saravana Kannan <saravanak@google.com>,
	xypron.glpk@gmx.de,
	"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
	Bartosz Golaszewski <bgolaszewski@baylibre.com>,
	bskeggs@redhat.com, linux-pci@vger.kernel.org,
	xen-devel@lists.xenproject.org,
	Thierry Reding <treding@nvidia.com>,
	intel-gfx@lists.freedesktop.org, matthew.auld@intel.com,
	linux-devicetree <devicetree@vger.kernel.org>,
	airlied@linux.ie, Robin Murphy <robin.murphy@arm.com>,
	Nicolas Boichat <drinkcat@chromium.org>,
	bhelgaas@google.com, tientzu@chromium.org,
	Dan Williams <dan.j.williams@intel.com>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Greg KH <gregkh@linuxfoundation.org>,
	Randy Dunlap <rdunlap@infradead.org>,
	lkml <linux-kernel@vger.kernel.org>,
	tfiga@chromium.org,
	"list@263.net:IOMMU DRIVERS" <iommu@lists.linux-foundation.org>,
	Jim Quinlan <james.quinlan@broadcom.com>,
	linuxppc-dev@lists.ozlabs.org, bauerman@linux.ibm.com
Subject: [Intel-gfx] [PATCH v9 07/14] swiotlb: Bounce data from/to restricted DMA pool if available
Date: Fri, 11 Jun 2021 23:26:52 +0800	[thread overview]
Message-ID: <20210611152659.2142983-8-tientzu@chromium.org> (raw)
In-Reply-To: <20210611152659.2142983-1-tientzu@chromium.org>

Regardless of swiotlb setting, the restricted DMA pool is preferred if
available.

The restricted DMA pools provide a basic level of protection against the
DMA overwriting buffer contents at unexpected times. However, to protect
against general data leakage and system memory corruption, the system
needs to provide a way to lock down the memory access, e.g., MPU.

Note that is_dev_swiotlb_force doesn't check if
swiotlb_force == SWIOTLB_FORCE. Otherwise the memory allocation behavior
with default swiotlb will be changed by the following patche
("dma-direct: Allocate memory from restricted DMA pool if available").

Signed-off-by: Claire Chang <tientzu@chromium.org>
---
 include/linux/swiotlb.h | 10 +++++++++-
 kernel/dma/direct.c     |  3 ++-
 kernel/dma/direct.h     |  3 ++-
 kernel/dma/swiotlb.c    |  1 +
 4 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 06cf17a80f5c..8200c100fe10 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -85,6 +85,7 @@ extern enum swiotlb_force swiotlb_force;
  *		unmap calls.
  * @debugfs:	The dentry to debugfs.
  * @late_alloc:	%true if allocated using the page allocator
+ * @force_swiotlb: %true if swiotlb is forced
  */
 struct io_tlb_mem {
 	phys_addr_t start;
@@ -95,6 +96,7 @@ struct io_tlb_mem {
 	spinlock_t lock;
 	struct dentry *debugfs;
 	bool late_alloc;
+	bool force_swiotlb;
 	struct io_tlb_slot {
 		phys_addr_t orig_addr;
 		size_t alloc_size;
@@ -115,6 +117,11 @@ static inline void swiotlb_set_io_tlb_default_mem(struct device *dev)
 	dev->dma_io_tlb_mem = io_tlb_default_mem;
 }
 
+static inline bool is_dev_swiotlb_force(struct device *dev)
+{
+	return dev->dma_io_tlb_mem->force_swiotlb;
+}
+
 void __init swiotlb_exit(void);
 unsigned int swiotlb_max_segment(void);
 size_t swiotlb_max_mapping_size(struct device *dev);
@@ -126,8 +133,9 @@ static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
 {
 	return false;
 }
-static inline void swiotlb_set_io_tlb_default_mem(struct device *dev)
+static inline bool is_dev_swiotlb_force(struct device *dev)
 {
+	return false;
 }
 static inline void swiotlb_exit(void)
 {
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 7a88c34d0867..078f7087e466 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -496,7 +496,8 @@ size_t dma_direct_max_mapping_size(struct device *dev)
 {
 	/* If SWIOTLB is active, use its maximum mapping size */
 	if (is_swiotlb_active(dev) &&
-	    (dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE))
+	    (dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE ||
+	     is_dev_swiotlb_force(dev)))
 		return swiotlb_max_mapping_size(dev);
 	return SIZE_MAX;
 }
diff --git a/kernel/dma/direct.h b/kernel/dma/direct.h
index 13e9e7158d94..f94813674e23 100644
--- a/kernel/dma/direct.h
+++ b/kernel/dma/direct.h
@@ -87,7 +87,8 @@ static inline dma_addr_t dma_direct_map_page(struct device *dev,
 	phys_addr_t phys = page_to_phys(page) + offset;
 	dma_addr_t dma_addr = phys_to_dma(dev, phys);
 
-	if (unlikely(swiotlb_force == SWIOTLB_FORCE))
+	if (unlikely(swiotlb_force == SWIOTLB_FORCE) ||
+	    is_dev_swiotlb_force(dev))
 		return swiotlb_map(dev, phys, size, dir, attrs);
 
 	if (unlikely(!dma_capable(dev, dma_addr, size, true))) {
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 21e99907edd6..e5ccc198d0a7 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -714,6 +714,7 @@ static int rmem_swiotlb_device_init(struct reserved_mem *rmem,
 			return -ENOMEM;
 
 		swiotlb_init_io_tlb_mem(mem, rmem->base, nslabs, false, true);
+		mem->force_swiotlb = true;
 
 		rmem->priv = mem;
 
-- 
2.32.0.272.g935e593368-goog

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

  parent reply	other threads:[~2021-06-11 15:29 UTC|newest]

Thread overview: 144+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-11 15:26 [PATCH v9 00/14] Restricted DMA Claire Chang
2021-06-11 15:26 ` [Intel-gfx] " Claire Chang
2021-06-11 15:26 ` Claire Chang
2021-06-11 15:26 ` Claire Chang
2021-06-11 15:26 ` Claire Chang
2021-06-11 15:26 ` [PATCH v9 01/14] swiotlb: Refactor swiotlb init functions Claire Chang
2021-06-11 15:26   ` [Intel-gfx] " Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-14  6:16   ` Christoph Hellwig
2021-06-14  6:16     ` [Intel-gfx] " Christoph Hellwig
2021-06-14  6:16     ` Christoph Hellwig
2021-06-14  6:16     ` Christoph Hellwig
2021-06-15  4:06     ` Claire Chang
2021-06-15  4:06       ` Claire Chang
2021-06-15  4:06       ` [Intel-gfx] " Claire Chang
2021-06-15  4:06       ` Claire Chang
2021-06-15  4:06       ` Claire Chang
2021-06-15  4:06       ` Claire Chang
2021-06-11 15:26 ` [PATCH v9 02/14] swiotlb: Refactor swiotlb_create_debugfs Claire Chang
2021-06-11 15:26   ` [Intel-gfx] " Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-14  6:17   ` Christoph Hellwig
2021-06-14  6:17     ` [Intel-gfx] " Christoph Hellwig
2021-06-14  6:17     ` Christoph Hellwig
2021-06-14  6:17     ` Christoph Hellwig
2021-06-11 15:26 ` [PATCH v9 03/14] swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used Claire Chang
2021-06-11 15:26   ` [Intel-gfx] " Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:33   ` Claire Chang
2021-06-11 15:33     ` Claire Chang
2021-06-11 15:33     ` [Intel-gfx] " Claire Chang
2021-06-11 15:33     ` Claire Chang
2021-06-11 15:33     ` Claire Chang
2021-06-11 15:33     ` Claire Chang
2021-06-14  6:20     ` Christoph Hellwig
2021-06-14  6:20       ` [Intel-gfx] " Christoph Hellwig
2021-06-14  6:20       ` Christoph Hellwig
2021-06-14  6:20       ` Christoph Hellwig
2021-06-11 15:26 ` [PATCH v9 04/14] swiotlb: Add restricted DMA pool initialization Claire Chang
2021-06-11 15:26   ` [Intel-gfx] " Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-14  6:21   ` Christoph Hellwig
2021-06-14  6:21     ` [Intel-gfx] " Christoph Hellwig
2021-06-14  6:21     ` Christoph Hellwig
2021-06-14  6:21     ` Christoph Hellwig
2021-06-11 15:26 ` [PATCH v9 05/14] swiotlb: Update is_swiotlb_buffer to add a struct device argument Claire Chang
2021-06-11 15:26   ` [Intel-gfx] " Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-14  6:21   ` Christoph Hellwig
2021-06-14  6:21     ` [Intel-gfx] " Christoph Hellwig
2021-06-14  6:21     ` Christoph Hellwig
2021-06-14  6:21     ` Christoph Hellwig
2021-06-11 15:26 ` [PATCH v9 06/14] swiotlb: Update is_swiotlb_active " Claire Chang
2021-06-11 15:26   ` [Intel-gfx] " Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:34   ` Claire Chang
2021-06-11 15:34     ` Claire Chang
2021-06-11 15:34     ` [Intel-gfx] " Claire Chang
2021-06-11 15:34     ` Claire Chang
2021-06-11 15:34     ` Claire Chang
2021-06-11 15:34     ` Claire Chang
2021-06-14  6:23   ` Christoph Hellwig
2021-06-14  6:23     ` [Intel-gfx] " Christoph Hellwig
2021-06-14  6:23     ` Christoph Hellwig
2021-06-14  6:23     ` Christoph Hellwig
2021-06-11 15:26 ` Claire Chang [this message]
2021-06-11 15:26   ` [Intel-gfx] [PATCH v9 07/14] swiotlb: Bounce data from/to restricted DMA pool if available Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-14  6:25   ` Christoph Hellwig
2021-06-14  6:25     ` [Intel-gfx] " Christoph Hellwig
2021-06-14  6:25     ` Christoph Hellwig
2021-06-14  6:25     ` Christoph Hellwig
2021-06-11 15:26 ` [PATCH v9 08/14] swiotlb: Move alloc_size to find_slots Claire Chang
2021-06-11 15:26   ` [Intel-gfx] " Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-14  6:25   ` Christoph Hellwig
2021-06-14  6:25     ` [Intel-gfx] " Christoph Hellwig
2021-06-14  6:25     ` Christoph Hellwig
2021-06-14  6:25     ` Christoph Hellwig
2021-06-11 15:26 ` [PATCH v9 09/14] swiotlb: Refactor swiotlb_tbl_unmap_single Claire Chang
2021-06-11 15:26   ` [Intel-gfx] " Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-14  6:26   ` Christoph Hellwig
2021-06-14  6:26     ` [Intel-gfx] " Christoph Hellwig
2021-06-14  6:26     ` Christoph Hellwig
2021-06-14  6:26     ` Christoph Hellwig
2021-06-11 15:26 ` [PATCH v9 10/14] dma-direct: Add a new wrapper __dma_direct_free_pages() Claire Chang
2021-06-11 15:26   ` [Intel-gfx] " Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26 ` [PATCH v9 11/14] swiotlb: Add restricted DMA alloc/free support Claire Chang
2021-06-11 15:26   ` [Intel-gfx] " Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-14  6:28   ` Christoph Hellwig
2021-06-14  6:28     ` [Intel-gfx] " Christoph Hellwig
2021-06-14  6:28     ` Christoph Hellwig
2021-06-14  6:28     ` Christoph Hellwig
2021-06-14  6:28     ` Christoph Hellwig
2021-06-14  6:28       ` [Intel-gfx] " Christoph Hellwig
2021-06-14  6:28       ` Christoph Hellwig
2021-06-14  6:28       ` Christoph Hellwig
2021-06-11 15:26 ` [PATCH v9 12/14] dma-direct: Allocate memory from restricted DMA pool if available Claire Chang
2021-06-11 15:26   ` [Intel-gfx] " Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26 ` [PATCH v9 13/14] dt-bindings: of: Add restricted DMA pool Claire Chang
2021-06-11 15:26   ` [Intel-gfx] " Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26 ` [PATCH v9 14/14] of: Add plumbing for " Claire Chang
2021-06-11 15:26   ` [Intel-gfx] " Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 15:26   ` Claire Chang
2021-06-11 17:37 ` [Intel-gfx] ✗ Fi.CI.BUILD: failure for Restricted DMA Patchwork
2021-06-15 13:30 ` [PATCH v9 00/14] " Claire Chang
2021-06-15 13:30   ` Claire Chang
2021-06-15 13:30   ` [Intel-gfx] " Claire Chang
2021-06-15 13:30   ` Claire Chang
2021-06-15 13:30   ` Claire Chang
2021-06-15 13:30   ` Claire Chang

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210611152659.2142983-8-tientzu@chromium.org \
    --to=tientzu@chromium.org \
    --cc=airlied@linux.ie \
    --cc=andriy.shevchenko@linux.intel.com \
    --cc=bauerman@linux.ibm.com \
    --cc=benh@kernel.crashing.org \
    --cc=bgolaszewski@baylibre.com \
    --cc=bhelgaas@google.com \
    --cc=boris.ostrovsky@oracle.com \
    --cc=bskeggs@redhat.com \
    --cc=chris@chris-wilson.co.uk \
    --cc=dan.j.williams@intel.com \
    --cc=daniel@ffwll.ch \
    --cc=devicetree@vger.kernel.org \
    --cc=dri-devel@lists.freedesktop.org \
    --cc=drinkcat@chromium.org \
    --cc=frowand.list@gmail.com \
    --cc=grant.likely@arm.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=hch@lst.de \
    --cc=heikki.krogerus@linux.intel.com \
    --cc=intel-gfx@lists.freedesktop.org \
    --cc=iommu@lists.linux-foundation.org \
    --cc=james.quinlan@broadcom.com \
    --cc=jani.nikula@linux.intel.com \
    --cc=jgross@suse.com \
    --cc=joonas.lahtinen@linux.intel.com \
    --cc=joro@8bytes.org \
    --cc=jxgao@google.com \
    --cc=konrad.wilk@oracle.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=m.szyprowski@samsung.com \
    --cc=maarten.lankhorst@linux.intel.com \
    --cc=matthew.auld@intel.com \
    --cc=mingo@kernel.org \
    --cc=mpe@ellerman.id.au \
    --cc=paulus@samba.org \
    --cc=peterz@infradead.org \
    --cc=rafael.j.wysocki@intel.com \
    --cc=rdunlap@infradead.org \
    --cc=robh+dt@kernel.org \
    --cc=robin.murphy@arm.com \
    --cc=rodrigo.vivi@intel.com \
    --cc=saravanak@google.com \
    --cc=sstabellini@kernel.org \
    --cc=tfiga@chromium.org \
    --cc=thomas.hellstrom@linux.intel.com \
    --cc=treding@nvidia.com \
    --cc=will@kernel.org \
    --cc=xen-devel@lists.xenproject.org \
    --cc=xypron.glpk@gmx.de \
    --subject='Re: [PATCH v9 07/14] swiotlb: Bounce data from/to restricted DMA pool if available' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.