On 9/21/26 10:40 AM, Shahyan Soltani wrote:
On 9/18/26 3:57 AM, Christian König wrote:


On 9/17/26 21:58, Shahyan Soltani wrote:
From: Pierre-Eric Pelloux-Prayer <[email protected]>

For now use the same logic as the existing one, but it's not 100%
correct since:
1) most operations don't need the GPUs
2) some operations that need it are actually deferred

Signed-off-by: Pierre-Eric Pelloux-Prayer <[email protected]>
Signed-off-by: Shahyan Soltani <[email protected]>
---
  drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c | 10 ++++++++++
  1 file changed, 10 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
index 4e4814caf61a..6edd03647c2d 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
@@ -978,6 +978,14 @@ int amdgpu_gem_va_ioctl(struct drm_device *dev, void *data,
      if (r)
          goto error;
  +    /* FIXME: only PRT operations use the GPU to update mapping, but
+     * some operations are deferred to fences callbacks so it's not
+     * trivial to fix.
+     */
That comment is not correct, just drop it.

+    r = pm_runtime_resume_and_get(adev->dev);
+    if (r < 0)
+        return r;
+
      switch (args->operation) {
      case AMDGPU_VA_OP_MAP:
          r = amdgpu_vm_bo_map(adev, bo_va, args->va_address,
@@ -1031,6 +1039,8 @@ int amdgpu_gem_va_ioctl(struct drm_device *dev, void *data,
        }
  +    pm_runtime_put_autosuspend(adev->dev);
That error handling is not correct, after the switch there are a bunch of returns and gotos for cleanup.

I strongly suggest to use the guard approach here as well.

Regards,
Christian.

Thanks for the feedback, you caught something I completely missed. However I have a few concerns
on what approaches I could take.

Attempting to use a guard in this situation would require the guard to be moved to the top of the function,
resuming the system much early in the stack.

As far as I understand this is due to the guard not being able to succeed any gotos as the "lock" variable
in the guard must be initialized before any subsequent goto.

For example:

goto error;
PM_RUNTIME_ACQUIRE_IF_ENABLED_AUTOSUSPEND(dev->dev, lock);

Is invalid as "lock" is initialized after the goto.
Trying to initialize lock beforehand doesn't work as it would count as a redefinition of lock instead.

Would that still be preferred over creating a new label and trying something like this instead?

replace

+    r = pm_runtime_resume_and_get(adev->dev);
+    if (r < 0)
+        return r;

with

+    r = pm_runtime_resume_and_get(adev->dev);
+    if (r < 0)
+        goto newlabel;

    }

...

+ newlabel:
+    pm_runtime_put_autosuspend(adev->dev);
error:
    dma_fence_chain_free(timeline_chain);
    if (timeline_syncobj)
        drm_syncobj_put(timeline_syncobj);
    drm_exec_fini(&exec);
error_put_gobj:
    drm_gem_object_put(gobj);
    return r;
}

Another approach I could try is wrap the entirePM_RUNTIME_ACQUIRE_IF_ENABLED_AUTOSUSPEND(dev->dev, lock); and the subsequent switch cases before the error handling into its own scope with {} However, I feel this method is a lot more hacky then necessary. int amdgpu_gem_va_ioctl(struct drm_device *dev, void *data, struct drm_file *filp) { ... + { + PM_RUNTIME_ACQUIRE_IF_ENABLED_AUTOSUSPEND(dev->dev, lock); + + r = PM_RUNTIME_ACQUIRE_ERR(&lock); + if (r) + goto error; switch (args->operation) { case AMDGPU_VA_OP_MAP: ... case AMDGPU_VA_OP_UNMAP: .. case AMDGPU_VA_OP_CLEAR: ... case AMDGPU_VA_OP_REPLACE: ... default: ... } if (!r && !(args->flags & AMDGPU_VM_DELAY_UPDATE) && (!adev->debug_vm || timeline_syncobj)) { ... } + } error: ... error_put_gobj: ... } If you have any ideas on what approach I should/could take it would be very much appreciated. Thanks, Shahyan

I'm not entirely sure what happened here...

But I meant to say wrapping the guard and the subsequent case handling into its own scope.

For example:

int amdgpu_gem_va_ioctl() {
...
    goto error;

+    {
+        PM_RUNTIME_ACQUIRE_IF_ENABLED_AUTOSUSPEND(dev->dev, lock);
+        r = PM_RUNTIME_ACQUIRE_ERR(&lock);
+        if (r)
+            goto error;

...
+    }
error:
...
error_put_gobj:
...
}

Thanks,
Shahyan

+
  error:
      dma_fence_chain_free(timeline_chain);
      if (timeline_syncobj)

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