diff options
| author | Jesse Zhang <Jesse.Zhang@amd.com> | 2026-09-30 14:21:19 +0800 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2026-10-07 11:56:04 -0400 |
| commit | f7497bbc19db4821c62b9d97b31c9086feb2d917 (patch) | |
| tree | b7a2cd163fcf68d601b3ee9bfb44c73d49dd35ee | |
| parent | 0bef0a6c2cb3b128af313c8c30a8a9385b64f944 (diff) | |
drm/amdgpu/userq: only accept doorbell BOs as queue doorbell
amdgpu_userq_get_doorbell_index() pins any BO passed as doorbell_handle
into the doorbell domain. For a regular BO, TTM moves it with
ttm_bo_move_null() and its contents are lost. Since an importer on the
same device gets the exporter's GEM object, a client can do this to a
buffer another client shared with it.
Reject BOs that were not created in the doorbell domain.
v2: drop the error message, use a local abo variable (Christian)
Fixes: f09c1e6077ab ("drm/amdgpu: generate doorbell index for userqueue")
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Jesse Zhang <Jesse.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
| -rw-r--r-- | drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c index 63875761dfac..e29823ae8672 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c @@ -469,6 +469,7 @@ amdgpu_userq_get_doorbell_index(struct amdgpu_userq_mgr *uq_mgr, u64 doorbell_index; struct drm_gem_object *gobj; struct amdgpu_userq_obj *db_obj = db_info->db_obj; + struct amdgpu_bo *abo; int r, db_size; gobj = drm_gem_object_lookup(filp, db_info->doorbell_handle); @@ -477,7 +478,17 @@ amdgpu_userq_get_doorbell_index(struct amdgpu_userq_mgr *uq_mgr, return -EINVAL; } - db_obj->obj = amdgpu_bo_ref(gem_to_amdgpu_bo(gobj)); + /* + * Pinning a regular BO into the doorbell domain would discard its + * contents, possibly those of a buffer shared by another client. + */ + abo = gem_to_amdgpu_bo(gobj); + if (!(abo->preferred_domains & AMDGPU_GEM_DOMAIN_DOORBELL)) { + drm_gem_object_put(gobj); + return -EINVAL; + } + + db_obj->obj = amdgpu_bo_ref(abo); drm_gem_object_put(gobj); r = amdgpu_bo_reserve(db_obj->obj, true); |