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RCVD_TLS_ALL(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; DNSWL_BLOCKED(0.00)[2a07:de40:b281:104:10:150:64:97:from]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; RECEIVED_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:106:10:150:64:167:received]; RCVD_VIA_SMTP_AUTH(0.00)[]; TAGGED_RCPT(0.00)[etnaviv]; DKIM_TRACE(0.00)[suse.de:+]; R_RATELIMIT(0.00)[to_ip_from(RLau4tukfh38qp3nirdnk14qe9)]; DBL_BLOCKED_OPENRESOLVER(0.00)[imap1.dmz-prg2.suse.org:rdns, imap1.dmz-prg2.suse.org:helo, suse.de:dkim, suse.de:mid, suse.de:email] X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" This reverts commit f83a9b8c7fd0557b0c50784bfdc1bbe9140c9bf8. The dma_buf field in struct drm_gem_object is not stable over the object instance's lifetime. The field becomes NULL when user space releases the final GEM handle on the buffer object. This resulted in a NULL-pointer deref. Workarounds in commit 5307dce878d4 ("drm/gem: Acquire references on GEM handles for framebuffers") and commit f6bfc9afc751 ("drm/framebuffer: Acquire internal references on GEM handles") only solved the problem partially. They especially don't work for buffer objects without a DRM framebuffer associated. Hence, this revert to going back to using .import_attach->dmabuf. v3: - cc stable Signed-off-by: Thomas Zimmermann Reviewed-by: Simona Vetter Acked-by: Christian König Cc: # v6.15+ --- drivers/gpu/drm/drm_prime.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c index b703f83874e1..a23fc712a8b7 100644 --- a/drivers/gpu/drm/drm_prime.c +++ b/drivers/gpu/drm/drm_prime.c @@ -453,7 +453,13 @@ struct dma_buf *drm_gem_prime_handle_to_dmabuf(struct drm_device *dev, } mutex_lock(&dev->object_name_lock); - /* re-export the original imported/exported object */ + /* re-export the original imported object */ + if (obj->import_attach) { + dmabuf = obj->import_attach->dmabuf; + get_dma_buf(dmabuf); + goto out_have_obj; + } + if (obj->dma_buf) { get_dma_buf(obj->dma_buf); dmabuf = obj->dma_buf; -- 2.50.0