Re: [Intel-gfx] [PATCH 2/3] drm/i915: Never return 0 on timeout when retiring requests

[Das, Nirmoy]

Looks very relevant to  our recent hangcheck failures.


Acked-by: Nirmoy Das 

On 11/16/2022 12:25 PM, Janusz Krzysztofik wrote:

Users of intel_gt_retire_requests_timeout() expect 0 return value on
success.  However, we have no protection from passing back 0 potentially
returned by dma_fence_wait_timeout() on timeout.

Replace 0 with -ETIME before using timeout as return value.

Fixes: f33a8a51602c ("drm/i915: Merge wait_for_timelines with retire_request")
Signed-off-by: Janusz Krzysztofik 
Cc: sta...@vger.kernel.org # v5.5+
---
  drivers/gpu/drm/i915/gt/intel_gt_requests.c | 3 +++
  1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/i915/gt/intel_gt_requests.c 
b/drivers/gpu/drm/i915/gt/intel_gt_requests.c
index ccaf2fd80625b..ac6b2b1861397 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_requests.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt_requests.c
@@ -213,6 +213,9 @@ out_active: spin_lock(>lock);
list_for_each_entry_safe(tl, tn, , link)
__intel_timeline_free(>kref);
  
+	if (!timeout)

+   timeout = -ETIME;
+
if (flush_submission(gt, timeout)) /* Wait, there's more! */
active_count++;
  

Re: [Intel-gfx] [PATCH 2/3] drm/i915: Never return 0 on timeout when retiring requests

[Andrzej Hajda]

On 16.11.2022 12:25, Janusz Krzysztofik wrote:

Users of intel_gt_retire_requests_timeout() expect 0 return value on
success.  However, we have no protection from passing back 0 potentially
returned by dma_fence_wait_timeout() on timeout.

Replace 0 with -ETIME before using timeout as return value.

Fixes: f33a8a51602c ("drm/i915: Merge wait_for_timelines with retire_request")
Signed-off-by: Janusz Krzysztofik 
Cc: sta...@vger.kernel.org # v5.5+
---
  drivers/gpu/drm/i915/gt/intel_gt_requests.c | 3 +++
  1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/i915/gt/intel_gt_requests.c 
b/drivers/gpu/drm/i915/gt/intel_gt_requests.c
index ccaf2fd80625b..ac6b2b1861397 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_requests.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt_requests.c
@@ -213,6 +213,9 @@ out_active: spin_lock(>lock);
list_for_each_entry_safe(tl, tn, , link)
__intel_timeline_free(>kref);
  
+	if (!timeout)

+   timeout = -ETIME;
+




Reviewed-by: Andrzej Hajda 

Regards
Andrzej


if (flush_submission(gt, timeout)) /* Wait, there's more! */
active_count++;