diff options
| author | Arvind Yadav <arvind.yadav@intel.com> | 2026-03-26 18:38:35 +0530 |
|---|---|---|
| committer | Matthew Brost <matthew.brost@intel.com> | 2026-03-26 19:59:53 -0700 |
| commit | da857c9a48874dff183a10348ab1a49ffba1ec1e (patch) | |
| tree | eed44043e019d31b9a9a513224c77417bec89dc1 /drivers/gpu/drm/xe | |
| parent | 975bc3ea4cca58deadfaf64121eb71e2da39571d (diff) | |
drm/xe/dma_buf: Block export of DONTNEED/purged BOs
Don't allow exporting BOs marked DONTNEED or PURGED as dma-bufs.
DONTNEED BOs can have their contents discarded at any time, making
the exported dma-buf unusable for external devices. PURGED BOs have
no backing store and are permanently invalid.
Return -EBUSY for DONTNEED BOs (temporary purgeable state) and
-EINVAL for purged BOs (permanent, no backing store).
The export path now checks the BO's purgeable state before creating
the dma-buf, preventing external devices from accessing memory that
may be purged at any time.
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Arvind Yadav <arvind.yadav@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patch.msgid.link/20260326130843.3545241-10-arvind.yadav@intel.com
Diffstat (limited to 'drivers/gpu/drm/xe')
| -rw-r--r-- | drivers/gpu/drm/xe/xe_dma_buf.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/drivers/gpu/drm/xe/xe_dma_buf.c b/drivers/gpu/drm/xe/xe_dma_buf.c index ea370cd373e9..7f9602b3363d 100644 --- a/drivers/gpu/drm/xe/xe_dma_buf.c +++ b/drivers/gpu/drm/xe/xe_dma_buf.c @@ -223,6 +223,26 @@ struct dma_buf *xe_gem_prime_export(struct drm_gem_object *obj, int flags) if (bo->vm) return ERR_PTR(-EPERM); + /* + * Reject exporting purgeable BOs. DONTNEED BOs can be purged + * at any time, making the exported dma-buf unusable. Purged BOs + * have no backing store and are permanently invalid. + */ + ret = xe_bo_lock(bo, true); + if (ret) + return ERR_PTR(ret); + + if (xe_bo_madv_is_dontneed(bo)) { + ret = -EBUSY; + goto out_unlock; + } + + if (xe_bo_is_purged(bo)) { + ret = -EINVAL; + goto out_unlock; + } + xe_bo_unlock(bo); + ret = ttm_bo_setup_export(&bo->ttm, &ctx); if (ret) return ERR_PTR(ret); @@ -232,6 +252,10 @@ struct dma_buf *xe_gem_prime_export(struct drm_gem_object *obj, int flags) buf->ops = &xe_dmabuf_ops; return buf; + +out_unlock: + xe_bo_unlock(bo); + return ERR_PTR(ret); } static struct drm_gem_object * |