search for: dma_max_mapping_size

On Mon, Jul 22, 2019 at 04:55:09PM +0200, Eric Auger wrote: > Do not call dma_max_mapping_size for devices that have no DMA > mask set, otherwise we can hit a NULL pointer dereference. > > This occurs when a virtio-blk-pci device is protected with > a virtual IOMMU. > > Fixes: e6d6dd6c875e ("virtio: Introduce virtio_max_dma_size()") > Signed-off-by: Eric Auge...

On Mon, Jul 22, 2019 at 04:55:09PM +0200, Eric Auger wrote: > Do not call dma_max_mapping_size for devices that have no DMA > mask set, otherwise we can hit a NULL pointer dereference. > > This occurs when a virtio-blk-pci device is protected with > a virtual IOMMU. > > Fixes: e6d6dd6c875e ("virtio: Introduce virtio_max_dma_size()") > Signed-off-by: Eric Auge...

...ev); + #ifdef CONFIG_HAS_DMA #include <asm/dma-mapping.h> @@ -460,6 +463,7 @@ int dma_supported(struct device *dev, u64 mask); int dma_set_mask(struct device *dev, u64 mask); int dma_set_coherent_mask(struct device *dev, u64 mask); u64 dma_get_required_mask(struct device *dev); +size_t dma_max_mapping_size(struct device *dev); #else /* CONFIG_HAS_DMA */ static inline dma_addr_t dma_map_page_attrs(struct device *dev, struct page *page, size_t offset, size_t size, @@ -561,6 +565,10 @@ static inline u64 dma_get_required_mask(struct device *dev) { return 0; } +static inline size_t dma_max_mappin...

When running a guest featuring a virtio-blk-pci protected with a virtual IOMMU we hit a NULL pointer dereference. This series removes the dma_max_mapping_size() call in virtio_max_dma_size when the device does not have any dma_mask set. A check is also added to early return in dma_addressing_limited() if the dma_mask is NULL. Eric Auger (2): dma-mapping: Protect dma_addressing_limited against NULL dma_mask virtio/virtio_ring: Fix the dma_max_mapping...

On Mon, Jul 22, 2019 at 11:33:35AM -0400, Michael S. Tsirkin wrote: > On Mon, Jul 22, 2019 at 04:55:09PM +0200, Eric Auger wrote: > > Do not call dma_max_mapping_size for devices that have no DMA > > mask set, otherwise we can hit a NULL pointer dereference. > > > > This occurs when a virtio-blk-pci device is protected with > > a virtual IOMMU. > > > > Fixes: e6d6dd6c875e ("virtio: Introduce virtio_max_dma_size()")...

On 22/07/2019 15:55, Eric Auger wrote: > Do not call dma_max_mapping_size for devices that have no DMA > mask set, otherwise we can hit a NULL pointer dereference. > > This occurs when a virtio-blk-pci device is protected with > a virtual IOMMU. > > Fixes: e6d6dd6c875e ("virtio: Introduce virtio_max_dma_size()") > Signed-off-by: Eric Auge...

On 22/07/2019 15:55, Eric Auger wrote: > Do not call dma_max_mapping_size for devices that have no DMA > mask set, otherwise we can hit a NULL pointer dereference. > > This occurs when a virtio-blk-pci device is protected with > a virtual IOMMU. > > Fixes: e6d6dd6c875e ("virtio: Introduce virtio_max_dma_size()") > Signed-off-by: Eric Auge...

Do not call dma_max_mapping_size for devices that have no DMA mask set, otherwise we can hit a NULL pointer dereference. This occurs when a virtio-blk-pci device is protected with a virtual IOMMU. Fixes: e6d6dd6c875e ("virtio: Introduce virtio_max_dma_size()") Signed-off-by: Eric Auger <eric.auger at redhat.com>...

On Mon, Jul 22, 2019 at 04:55:09PM +0200, Eric Auger wrote: > Do not call dma_max_mapping_size for devices that have no DMA > mask set, otherwise we can hit a NULL pointer dereference. > > This occurs when a virtio-blk-pci device is protected with > a virtual IOMMU. > > Fixes: e6d6dd6c875e ("virtio: Introduce virtio_max_dma_size()") > Signed-off-by: Eric Auge...

...struct virtio_device *vdev) return false; } -size_t virtio_max_dma_size(const struct virtio_device *vdev) +u32 virtio_max_dma_size(const struct virtio_device *vdev) { - size_t max_segment_size = SIZE_MAX; + u32 max_segment_size = U32_MAX; - if (vring_use_dma_api(vdev)) - max_segment_size = dma_max_mapping_size(vdev->dev.parent); + if (vring_use_dma_api(vdev)) { + size_t max_dma_size = dma_max_mapping_size(vdev->dev.parent); + + if (max_dma_size < max_segment_size) + max_segment_size = max_dma_size; + } return max_segment_size; } diff --git a/include/linux/virtio.h b/include/linux/virtio...

On Mon, Jul 22, 2019 at 04:36:09PM +0100, Robin Murphy wrote: >> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c >> index c8be1c4f5b55..37c143971211 100644 >> --- a/drivers/virtio/virtio_ring.c >> +++ b/drivers/virtio/virtio_ring.c >> @@ -262,7 +262,7 @@ size_t virtio_max_dma_size(struct virtio_device *vdev) >> { >> size_t

On Tue, Jul 23, 2019 at 05:38:51PM +0200, Christoph Hellwig wrote: > On Mon, Jul 22, 2019 at 04:36:09PM +0100, Robin Murphy wrote: > >> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > >> index c8be1c4f5b55..37c143971211 100644 > >> --- a/drivers/virtio/virtio_ring.c > >> +++ b/drivers/virtio/virtio_ring.c > >> @@ -262,7

On Thu, Jul 25, 2019 at 01:53:49PM +0200, Auger Eric wrote: > I am confused: if vring_use_dma_api() returns false if the dma_mask is > unset (ie. vring_use_dma_api() returns false), the virtio-blk-pci device > will not be able to get translated addresses and won't work properly. > > The patch above allows the dma api to be used and only influences the > max_segment_size and

On Mon, Sep 07, 2020 at 03:53:02PM +0200, Daniel Vetter wrote: > On Mon, Sep 7, 2020 at 1:24 PM Gerd Hoffmann <kraxel at redhat.com> wrote: > > > > Add drm_device argument to drm_prime_pages_to_sg(), so we can > > call dma_max_mapping_size() to figure the segment size limit > > and call into __sg_alloc_table_from_pages() with the correct > > limit. > > > > This fixes virtio-gpu with sev. Possibly it'll fix other bugs > > too given that drm seems to totaly ignore segment size limits > > so far...

Hi, On 7/23/19 5:38 PM, Christoph Hellwig wrote: > On Mon, Jul 22, 2019 at 04:36:09PM +0100, Robin Murphy wrote: >>> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c >>> index c8be1c4f5b55..37c143971211 100644 >>> --- a/drivers/virtio/virtio_ring.c >>> +++ b/drivers/virtio/virtio_ring.c >>> @@ -262,7 +262,7 @@ size_t

Hi, On 7/23/19 5:38 PM, Christoph Hellwig wrote: > On Mon, Jul 22, 2019 at 04:36:09PM +0100, Robin Murphy wrote: >>> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c >>> index c8be1c4f5b55..37c143971211 100644 >>> --- a/drivers/virtio/virtio_ring.c >>> +++ b/drivers/virtio/virtio_ring.c >>> @@ -262,7 +262,7 @@ size_t

...io_max_dma_size(const struct virtio_device *vdev) LGTM But, should we change the parameter to vq, then use the dma_dev? @Jason Thanks. > { > - size_t max_segment_size = SIZE_MAX; > + u32 max_segment_size = U32_MAX; > > - if (vring_use_dma_api(vdev)) > - max_segment_size = dma_max_mapping_size(vdev->dev.parent); > + if (vring_use_dma_api(vdev)) { > + size_t max_dma_size = dma_max_mapping_size(vdev->dev.parent); > + > + if (max_dma_size < max_segment_size) > + max_segment_size = max_dma_size; > + } > > return max_segment_size; > } > diff --git...

...n that, the allocation of the dma-handle fails and an IO error is reported. Changes to v6 are: - Fix build errors with CONFIG_SWIOTLB=n Please review. Thanks, Joerg Joerg Roedel (5): swiotlb: Introduce swiotlb_max_mapping_size() swiotlb: Add is_swiotlb_active() function dma: Introduce dma_max_mapping_size() virtio: Introduce virtio_max_dma_size() virtio-blk: Consider virtio_max_dma_size() for maximum segment size Documentation/DMA-API.txt | 8 ++++++++ drivers/block/virtio_blk.c | 10 ++++++---- drivers/virtio/virtio_ring.c | 11 +++++++++++ include/linux/dma-mapping.h | 8 ++++++++ in...

...} > > -size_t virtio_max_dma_size(const struct virtio_device *vdev) > +u32 virtio_max_dma_size(const struct virtio_device *vdev) > { > - size_t max_segment_size = SIZE_MAX; > + u32 max_segment_size = U32_MAX; > > - if (vring_use_dma_api(vdev)) > - max_segment_size = dma_max_mapping_size(vdev->dev.parent); > + if (vring_use_dma_api(vdev)) { > + size_t max_dma_size = dma_max_mapping_size(vdev->dev.parent); > + > + if (max_dma_size < max_segment_size) > + max_segment_size = max_dma_size; > + } > > return max_segment_size; > } > diff --g...

...} > > -size_t virtio_max_dma_size(const struct virtio_device *vdev) > +u32 virtio_max_dma_size(const struct virtio_device *vdev) > { > - size_t max_segment_size = SIZE_MAX; > + u32 max_segment_size = U32_MAX; > > - if (vring_use_dma_api(vdev)) > - max_segment_size = dma_max_mapping_size(vdev->dev.parent); > + if (vring_use_dma_api(vdev)) { > + size_t max_dma_size = dma_max_mapping_size(vdev->dev.parent); > + > + if (max_dma_size < max_segment_size) > + max_segment_size = max_dma_size; > + } > > return max_segment_size; > } Took a while...