FAILED: patch "[PATCH] drm/amdgpu: avoid force-completing uninitialized UVD rings" failed to apply to 6.6-stable tree

The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 6760f5cb12d2366ddd58a2d8637f7583d73f596b
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026090944-uranium-paramedic-0401@gregkh' --subject-prefix 'PATCH 6.6.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 6760f5cb12d2366ddd58a2d8637f7583d73f596b Mon Sep 17 00:00:00 2001
From: Bob Zhou <[email protected]>
Date: Wed, 19 Aug 2026 14:23:49 +0800
Subject: [PATCH] drm/amdgpu: avoid force-completing uninitialized UVD rings

uvd_v7_0_sw_init() does not initialize the UVD decode ring for an SR-IOV VF. However, amdgpu_uvd_resume() unconditionally force-completes the decode ring when restoring its fence sequence.

Skip fence completion when the fence driver is not initialized.

index 228a405a94c4..ecd7caa95d4b 100644
@@ -517,7 +517,8 @@ int amdgpu_uvd_resume(struct amdgpu_device *adev)
 			}
 			memset_io(ptr, 0, size);
 			/* to restore uvd fence seq */
-			amdgpu_fence_driver_force_completion(&adev->uvd.inst[i].ring, NULL);
+			if (adev->uvd.inst[i].ring.fence_drv.initialized)
+				amdgpu_fence_driver_force_completion(&adev->uvd.inst[i].ring, NULL);
 		}
 	}
 	return 0;

From: Srinivasan Shanmugam <[email protected]>

[ Upstream commit ba038065655c45728be346d0b174a6da08d8a5c5 ]

amdgpu_ib_schedule() returns early after calling amdgpu_ring_undo(). This skips the common free_fence cleanup path. Other error paths were already changed to use goto free_fence, but this one was missed.

Change the early return to goto free_fence so all error paths clean up the same way.

Fixes the below:
drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c:232 amdgpu_ib_schedule()
warn: missing unwind goto?

drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c

    124 int amdgpu_ib_schedule(struct amdgpu_ring *ring, unsigned int num_ibs,
    125                        struct amdgpu_ib *ibs, struct amdgpu_job *job,
    126                        struct dma_fence **f)
    127 {

    ...

    224
    225         if (ring->funcs->insert_start)
    226                 ring->funcs->insert_start(ring);
    227
    228         if (job) {
    229                 r = amdgpu_vm_flush(ring, job, need_pipe_sync);
    230                 if (r) {
    231                         amdgpu_ring_undo(ring);

--> 232 return r;

	The patch changed the other error paths to goto free_fence but
	this one was accidentally skipped.

    233                 }
    234         }
    235
    236         amdgpu_ring_ib_begin(ring);

    ...

    338
    339 free_fence:
    340         if (!job)
    341                 kfree(af);
    342         return r;
    343 }

Stable-dep-of: 6760f5cb12d2 ("drm/amdgpu: avoid force-completing uninitialized UVD rings")

---
 drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index 806ec5d021995..2cce0a378ecb3 100644
@@ -217,7 +217,7 @@ int amdgpu_ib_schedule(struct amdgpu_ring *ring, unsigned int num_ibs,
 		r = amdgpu_vm_flush(ring, job, need_pipe_sync);
 		if (r) {
 			amdgpu_ring_undo(ring);
-			return r;
+			goto free_fence;
 		}
 	}
 

2.53.0

From: Alex Deucher <[email protected]>

[ Upstream commit c184df870db1e328691ea0fbb7d0e59efd9d3f9f ]

When we do a full adapter reset, if we know the timedout fence mark the fence with -ETIME rather than -ECANCELED so it gets properly handled by userspace.

v2: rebase

Stable backport notes:
- Keep the two-argument force-completion API and its existing callers so 6760f5cb12d2 can add the UVD fence-driver initialization check unchanged.
- Use &job->hw_fence.base for 6.6's embedded hardware fence. Preserve the existing scheduler reset and job-fence clearing flow used for resubmission.
- Drop SDMA, VCN and JPEG reset hunks whose functions do not exist here; vcn_v5_0_1.c is also absent. Do not import newer queue-reset helpers or their declarations. No functions are added by this backport.
- Restore the direct return after amdgpu_ring_undo() on VM-flush failure. The earlier ccea36c819df backport introduced a goto free_fence without the label or the newer fence-allocation model it depends on. In 6.6, amdgpu_ib_schedule() has no locally allocated fence to free on this path. This restores the original 6.6 error handling and fixes the build without importing the unrelated fence-lifetime conversion.

[ sashal: Reduced backport -- upstream c184df870db1e touches 9 file(s), this
backport carries 6. Not backported here:
drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c drivers/gpu/drm/amd/amdgpu/vcn_v4_0_3.c drivers/gpu/drm/amd/amdgpu/vcn_v5_0_1.c
This note is generated from the file lists only; see the resolution record for the reasoning. ]

Stable-dep-of: 6760f5cb12d2 ("drm/amdgpu: avoid force-completing uninitialized UVD rings")

---
 drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c |  2 +-
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c  |  6 ++++-
 drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c   | 25 ++++++++++++++++++---
 drivers/gpu/drm/amd/amdgpu/amdgpu_ib.c      |  2 +-
 drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h    |  3 ++-
 drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c     |  2 +-
 6 files changed, 32 insertions(+), 8 deletions(-)

index 256cc15fc9b5a..2044f5cca3514 100644
@@ -1947,7 +1947,7 @@ static int amdgpu_debugfs_ib_preempt(void *data, u64 val)
 		/* swap out the old fences */
 		amdgpu_ib_preempt_fences_swap(ring, fences);
 
-		amdgpu_fence_driver_force_completion(ring);
+		amdgpu_fence_driver_force_completion(ring, NULL);
 
 		/* resubmit unfinished jobs */
 		amdgpu_ib_preempt_job_recovery(&ring->sched);

index 892a40c439637..60e1d9cda3a8b 100644
@@ -4894,6 +4894,7 @@ int amdgpu_device_pre_asic_reset(struct amdgpu_device *adev,
 {
 	int i, r = 0;
 	struct amdgpu_job *job = NULL;
+	struct dma_fence *fence = NULL;
 	bool need_full_reset =
 		test_bit(AMDGPU_NEED_FULL_RESET, &reset_context->flags);
 

@@ -4907,6 +4908,9 @@ int amdgpu_device_pre_asic_reset(struct amdgpu_device *adev,
 
 	amdgpu_fence_driver_isr_toggle(adev, true);
 
+	if (job)
+		fence = &job->hw_fence.base;
+
 	/* block all schedulers and reset given job's ring */
 	for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
 		struct amdgpu_ring *ring = adev->rings[i];

@@ -4920,7 +4924,7 @@ int amdgpu_device_pre_asic_reset(struct amdgpu_device *adev,
 		amdgpu_fence_driver_clear_job_fences(ring);
 
 		/* after all hw jobs are reset, hw fence is meaningless, so force_completion */
-		amdgpu_fence_driver_force_completion(ring);
+		amdgpu_fence_driver_force_completion(ring, fence);
 	}
 
 	amdgpu_fence_driver_isr_toggle(adev, false);

index 017dd494d0a2f..93208bd5631af 100644
@@ -595,7 +595,7 @@ void amdgpu_fence_driver_hw_fini(struct amdgpu_device *adev)
 			r = -ENODEV;
 		/* no need to trigger GPU reset as we are unloading */
 		if (r)
-			amdgpu_fence_driver_force_completion(ring);
+			amdgpu_fence_driver_force_completion(ring, NULL);
 
 		if (!drm_dev_is_unplugged(adev_to_drm(adev)) &&
 		    ring->fence_drv.irq_src &&

@@ -740,11 +740,30 @@ void amdgpu_fence_driver_set_error(struct amdgpu_ring *ring, int error)
  * amdgpu_fence_driver_force_completion - force signal latest fence of ring
  *
  * @ring: fence of the ring to signal
+ * @timedout_fence: fence of the timedout job
  *
  */
-void amdgpu_fence_driver_force_completion(struct amdgpu_ring *ring)
+void amdgpu_fence_driver_force_completion(struct amdgpu_ring *ring,
+					  struct dma_fence *timedout_fence)
 {
-	amdgpu_fence_driver_set_error(ring, -ECANCELED);
+	struct amdgpu_fence_driver *drv = &ring->fence_drv;
+	unsigned long flags;
+
+	spin_lock_irqsave(&drv->lock, flags);
+	for (unsigned int i = 0; i <= drv->num_fences_mask; ++i) {
+		struct dma_fence *fence;
+
+		fence = rcu_dereference_protected(drv->fences[i],
+						  lockdep_is_held(&drv->lock));
+		if (fence && !dma_fence_is_signaled_locked(fence)) {
+			if (fence == timedout_fence)
+				dma_fence_set_error(fence, -ETIME);
+			else
+				dma_fence_set_error(fence, -ECANCELED);
+		}
+	}
+	spin_unlock_irqrestore(&drv->lock, flags);
+
 	amdgpu_fence_write(ring, ring->fence_drv.sync_seq);
 	amdgpu_fence_process(ring);
 }

index 2cce0a378ecb3..806ec5d021995 100644
@@ -217,7 +217,7 @@ int amdgpu_ib_schedule(struct amdgpu_ring *ring, unsigned int num_ibs,
 		r = amdgpu_vm_flush(ring, job, need_pipe_sync);
 		if (r) {
 			amdgpu_ring_undo(ring);
-			goto free_fence;
+			return r;
 		}
 	}
 

index dc17e2ce84d07..b40dbe2f4fc25 100644
@@ -143,7 +143,8 @@ extern const struct drm_sched_backend_ops amdgpu_sched_ops;
 
 void amdgpu_fence_driver_clear_job_fences(struct amdgpu_ring *ring);
 void amdgpu_fence_driver_set_error(struct amdgpu_ring *ring, int error);
-void amdgpu_fence_driver_force_completion(struct amdgpu_ring *ring);
+void amdgpu_fence_driver_force_completion(struct amdgpu_ring *ring,
+					  struct dma_fence *timedout_fence);
 
 int amdgpu_fence_driver_init_ring(struct amdgpu_ring *ring);
 int amdgpu_fence_driver_start_ring(struct amdgpu_ring *ring,

index aab293ec3417e..b6047dea0a1c6 100644
@@ -511,7 +511,7 @@ int amdgpu_uvd_resume(struct amdgpu_device *adev)
 			}
 			memset_io(ptr, 0, size);
 			/* to restore uvd fence seq */
-			amdgpu_fence_driver_force_completion(&adev->uvd.inst[i].ring);
+			amdgpu_fence_driver_force_completion(&adev->uvd.inst[i].ring, NULL);
 		}
 	}
 	return 0;

2.53.0

From: Bob Zhou <[email protected]>

[ Upstream commit 6760f5cb12d2366ddd58a2d8637f7583d73f596b ]

uvd_v7_0_sw_init() does not initialize the UVD decode ring for an SR-IOV VF. However, amdgpu_uvd_resume() unconditionally force-completes the decode ring when restoring its fence sequence.

Skip fence completion when the fence driver is not initialized.

---
 drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

index b6047dea0a1c6..48d7a5b514151 100644
@@ -511,7 +511,8 @@ int amdgpu_uvd_resume(struct amdgpu_device *adev)
 			}
 			memset_io(ptr, 0, size);
 			/* to restore uvd fence seq */
-			amdgpu_fence_driver_force_completion(&adev->uvd.inst[i].ring, NULL);
+			if (adev->uvd.inst[i].ring.fence_drv.initialized)
+				amdgpu_fence_driver_force_completion(&adev->uvd.inst[i].ring, NULL);
 		}
 	}
 	return 0;

2.53.0