| Message ID | 20210927114114.152310-1-matthew.auld@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v5,01/13] drm/ttm: stop calling tt_swapin in vm_access | expand |
Any objections that I just push patches 1-7 to drm-misc-next? Christian. Am 27.09.21 um 13:41 schrieb Matthew Auld: > In commit: > > commit 09ac4fcb3f255e9225967c75f5893325c116cdbe > Author: Felix Kuehling <Felix.Kuehling@amd.com> > Date: Thu Jul 13 17:01:16 2017 -0400 > > drm/ttm: Implement vm_operations_struct.access v2 > > we added the vm_access hook, where we also directly call tt_swapin for > some reason. If something is swapped-out then the ttm_tt must also be > unpopulated, and since access_kmap should also call tt_populate, if > needed, then swapping-in will already be handled there. > > If anything, calling tt_swapin directly here would likely always fail > since the tt->pages won't yet be populated, or worse since the tt->pages > array is never actually cleared in unpopulate this might lead to a nasty > uaf. > > Fixes: 09ac4fcb3f25 ("drm/ttm: Implement vm_operations_struct.access v2") > Signed-off-by: Matthew Auld <matthew.auld@intel.com> > Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com> > Cc: Christian König <christian.koenig@amd.com> > Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> > Reviewed-by: Christian König <christian.koenig@amd.com> > --- > drivers/gpu/drm/ttm/ttm_bo_vm.c | 5 ----- > 1 file changed, 5 deletions(-) > > diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c > index f56be5bc0861..5b9b7fd01a69 100644 > --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c > +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c > @@ -519,11 +519,6 @@ int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr, > > switch (bo->resource->mem_type) { > case TTM_PL_SYSTEM: > - if (unlikely(bo->ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) { > - ret = ttm_tt_swapin(bo->ttm); > - if (unlikely(ret != 0)) > - return ret; > - } > fallthrough; > case TTM_PL_TT: > ret = ttm_bo_vm_access_kmap(bo, offset, buf, len, write);
On Mon, 27 Sept 2021 at 12:47, Christian König <christian.koenig@amd.com> wrote: > > Any objections that I just push patches 1-7 to drm-misc-next? Please go ahead Christian. Thanks. > > Christian. > > Am 27.09.21 um 13:41 schrieb Matthew Auld: > > In commit: > > > > commit 09ac4fcb3f255e9225967c75f5893325c116cdbe > > Author: Felix Kuehling <Felix.Kuehling@amd.com> > > Date: Thu Jul 13 17:01:16 2017 -0400 > > > > drm/ttm: Implement vm_operations_struct.access v2 > > > > we added the vm_access hook, where we also directly call tt_swapin for > > some reason. If something is swapped-out then the ttm_tt must also be > > unpopulated, and since access_kmap should also call tt_populate, if > > needed, then swapping-in will already be handled there. > > > > If anything, calling tt_swapin directly here would likely always fail > > since the tt->pages won't yet be populated, or worse since the tt->pages > > array is never actually cleared in unpopulate this might lead to a nasty > > uaf. > > > > Fixes: 09ac4fcb3f25 ("drm/ttm: Implement vm_operations_struct.access v2") > > Signed-off-by: Matthew Auld <matthew.auld@intel.com> > > Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com> > > Cc: Christian König <christian.koenig@amd.com> > > Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> > > Reviewed-by: Christian König <christian.koenig@amd.com> > > --- > > drivers/gpu/drm/ttm/ttm_bo_vm.c | 5 ----- > > 1 file changed, 5 deletions(-) > > > > diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c > > index f56be5bc0861..5b9b7fd01a69 100644 > > --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c > > +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c > > @@ -519,11 +519,6 @@ int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr, > > > > switch (bo->resource->mem_type) { > > case TTM_PL_SYSTEM: > > - if (unlikely(bo->ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) { > > - ret = ttm_tt_swapin(bo->ttm); > > - if (unlikely(ret != 0)) > > - return ret; > > - } > > fallthrough; > > case TTM_PL_TT: > > ret = ttm_bo_vm_access_kmap(bo, offset, buf, len, write); >
Am 27.09.21 um 18:14 schrieb Matthew Auld: > On Mon, 27 Sept 2021 at 12:47, Christian König <christian.koenig@amd.com> wrote: >> Any objections that I just push patches 1-7 to drm-misc-next? > Please go ahead Christian. Thanks. Well I've pushed patches #1-#4 because #5 won't apply on current drm-misc-next (some conflict in i915). Could you rebase this an/or request backmerging of drm-next into drm-misc-next when potential i915 prerequisites have landed there. Thanks, Christian. > >> Christian. >> >> Am 27.09.21 um 13:41 schrieb Matthew Auld: >>> In commit: >>> >>> commit 09ac4fcb3f255e9225967c75f5893325c116cdbe >>> Author: Felix Kuehling <Felix.Kuehling@amd.com> >>> Date: Thu Jul 13 17:01:16 2017 -0400 >>> >>> drm/ttm: Implement vm_operations_struct.access v2 >>> >>> we added the vm_access hook, where we also directly call tt_swapin for >>> some reason. If something is swapped-out then the ttm_tt must also be >>> unpopulated, and since access_kmap should also call tt_populate, if >>> needed, then swapping-in will already be handled there. >>> >>> If anything, calling tt_swapin directly here would likely always fail >>> since the tt->pages won't yet be populated, or worse since the tt->pages >>> array is never actually cleared in unpopulate this might lead to a nasty >>> uaf. >>> >>> Fixes: 09ac4fcb3f25 ("drm/ttm: Implement vm_operations_struct.access v2") >>> Signed-off-by: Matthew Auld <matthew.auld@intel.com> >>> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com> >>> Cc: Christian König <christian.koenig@amd.com> >>> Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> >>> Reviewed-by: Christian König <christian.koenig@amd.com> >>> --- >>> drivers/gpu/drm/ttm/ttm_bo_vm.c | 5 ----- >>> 1 file changed, 5 deletions(-) >>> >>> diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c >>> index f56be5bc0861..5b9b7fd01a69 100644 >>> --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c >>> +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c >>> @@ -519,11 +519,6 @@ int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr, >>> >>> switch (bo->resource->mem_type) { >>> case TTM_PL_SYSTEM: >>> - if (unlikely(bo->ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) { >>> - ret = ttm_tt_swapin(bo->ttm); >>> - if (unlikely(ret != 0)) >>> - return ret; >>> - } >>> fallthrough; >>> case TTM_PL_TT: >>> ret = ttm_bo_vm_access_kmap(bo, offset, buf, len, write);
On Wed, 29 Sept 2021 at 13:01, Christian König <christian.koenig@amd.com> wrote: > > Am 27.09.21 um 18:14 schrieb Matthew Auld: > > On Mon, 27 Sept 2021 at 12:47, Christian König <christian.koenig@amd.com> wrote: > >> Any objections that I just push patches 1-7 to drm-misc-next? > > Please go ahead Christian. Thanks. > > Well I've pushed patches #1-#4 because #5 won't apply on current > drm-misc-next (some conflict in i915). > > Could you rebase this an/or request backmerging of drm-next into > drm-misc-next when potential i915 prerequisites have landed there. Version which should apply to drm-misc-next: https://patchwork.freedesktop.org/series/95219/ > > Thanks, > Christian. > > > > >> Christian. > >> > >> Am 27.09.21 um 13:41 schrieb Matthew Auld: > >>> In commit: > >>> > >>> commit 09ac4fcb3f255e9225967c75f5893325c116cdbe > >>> Author: Felix Kuehling <Felix.Kuehling@amd.com> > >>> Date: Thu Jul 13 17:01:16 2017 -0400 > >>> > >>> drm/ttm: Implement vm_operations_struct.access v2 > >>> > >>> we added the vm_access hook, where we also directly call tt_swapin for > >>> some reason. If something is swapped-out then the ttm_tt must also be > >>> unpopulated, and since access_kmap should also call tt_populate, if > >>> needed, then swapping-in will already be handled there. > >>> > >>> If anything, calling tt_swapin directly here would likely always fail > >>> since the tt->pages won't yet be populated, or worse since the tt->pages > >>> array is never actually cleared in unpopulate this might lead to a nasty > >>> uaf. > >>> > >>> Fixes: 09ac4fcb3f25 ("drm/ttm: Implement vm_operations_struct.access v2") > >>> Signed-off-by: Matthew Auld <matthew.auld@intel.com> > >>> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com> > >>> Cc: Christian König <christian.koenig@amd.com> > >>> Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> > >>> Reviewed-by: Christian König <christian.koenig@amd.com> > >>> --- > >>> drivers/gpu/drm/ttm/ttm_bo_vm.c | 5 ----- > >>> 1 file changed, 5 deletions(-) > >>> > >>> diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c > >>> index f56be5bc0861..5b9b7fd01a69 100644 > >>> --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c > >>> +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c > >>> @@ -519,11 +519,6 @@ int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr, > >>> > >>> switch (bo->resource->mem_type) { > >>> case TTM_PL_SYSTEM: > >>> - if (unlikely(bo->ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) { > >>> - ret = ttm_tt_swapin(bo->ttm); > >>> - if (unlikely(ret != 0)) > >>> - return ret; > >>> - } > >>> fallthrough; > >>> case TTM_PL_TT: > >>> ret = ttm_bo_vm_access_kmap(bo, offset, buf, len, write); >
diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c index f56be5bc0861..5b9b7fd01a69 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c @@ -519,11 +519,6 @@ int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr, switch (bo->resource->mem_type) { case TTM_PL_SYSTEM: - if (unlikely(bo->ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) { - ret = ttm_tt_swapin(bo->ttm); - if (unlikely(ret != 0)) - return ret; - } fallthrough; case TTM_PL_TT: ret = ttm_bo_vm_access_kmap(bo, offset, buf, len, write);
In commit: commit 09ac4fcb3f255e9225967c75f5893325c116cdbe Author: Felix Kuehling <Felix.Kuehling@amd.com> Date: Thu Jul 13 17:01:16 2017 -0400 drm/ttm: Implement vm_operations_struct.access v2 we added the vm_access hook, where we also directly call tt_swapin for some reason. If something is swapped-out then the ttm_tt must also be unpopulated, and since access_kmap should also call tt_populate, if needed, then swapping-in will already be handled there. If anything, calling tt_swapin directly here would likely always fail since the tt->pages won't yet be populated, or worse since the tt->pages array is never actually cleared in unpopulate this might lead to a nasty uaf. Fixes: 09ac4fcb3f25 ("drm/ttm: Implement vm_operations_struct.access v2") Signed-off-by: Matthew Auld <matthew.auld@intel.com> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com> Cc: Christian König <christian.koenig@amd.com> Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Reviewed-by: Christian König <christian.koenig@amd.com> --- drivers/gpu/drm/ttm/ttm_bo_vm.c | 5 ----- 1 file changed, 5 deletions(-)