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* [PATCH] drm/xe/madvise: Remove unreachable madvise_funcs NULL check
@ 2026-09-15  1:12 Shuicheng Lin
  2026-09-15  1:20 ` ✓ CI.KUnit: success for drm/xe/madvise: Remove unreachable madvise_funcs NULL check (rev2) Patchwork
                   ` (2 more replies)
  0 siblings, 3 replies; 8+ messages in thread
From: Shuicheng Lin @ 2026-09-15  1:12 UTC (permalink / raw)
  To: intel-xe
  Cc: Shuicheng Lin, Arvind Yadav, Matthew Brost, Himal Prasad Ghimiray,
	Thomas Hellström

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The NULL check on madvise_funcs[attr_type] in xe_vm_madvise_ioctl()
is unreachable. madvise_args_are_sane() already validates args->type
via a switch statement whose default case rejects any type not present
in madvise_funcs[]. Every type that passes the sanity check has a
corresponding entry in the table.

Beyond being dead code, the check's error path (goto err_fini) would
also skip xe_svm_notifier_unlock() if it were somehow reached with
has_svm_userptr_vmas set, since err_fini only tears down the drm_exec.
Removing the check eliminates both the redundancy and the latent
unwind hazard.

No functional change.

Assisted-by: LLM
Signed-off-by: Shuicheng Lin <shuicheng.lin@intel.com>
---
Cc: Arvind Yadav <arvind.yadav@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
---
 drivers/gpu/drm/xe/xe_vm_madvise.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_vm_madvise.c b/drivers/gpu/drm/xe/xe_vm_madvise.c
index 0474768a38aa..5c7aefc641ee 100644
--- a/drivers/gpu/drm/xe/xe_vm_madvise.c
+++ b/drivers/gpu/drm/xe/xe_vm_madvise.c
@@ -713,12 +713,6 @@ int xe_vm_madvise_ioctl(struct drm_device *dev, void *data, struct drm_file *fil
 
 	attr_type = array_index_nospec(args->type, ARRAY_SIZE(madvise_funcs));
 
-	/* Ensure the madvise function exists for this type */
-	if (!madvise_funcs[attr_type]) {
-		err = -EINVAL;
-		goto err_fini;
-	}
-
 	madvise_funcs[attr_type](xe, vm, madvise_range.vmas, madvise_range.num_vmas, args,
 				 &details);
 
-- 
2.43.0


^ permalink raw reply related	[flat|nested] 8+ messages in thread
* [PATCH] drm/xe/madvise: Remove unreachable madvise_funcs NULL check
@ 2026-07-08 18:09 Shuicheng Lin
  0 siblings, 0 replies; 8+ messages in thread
From: Shuicheng Lin @ 2026-07-08 18:09 UTC (permalink / raw)
  To: intel-xe; +Cc: Shuicheng Lin

The NULL check on madvise_funcs[attr_type] in xe_vm_madvise_ioctl()
is unreachable. madvise_args_are_sane() already validates args->type
via a switch statement whose default case rejects any type not present
in madvise_funcs[]. Every type that passes the sanity check has a
corresponding entry in the table.

Beyond being dead code, the check's error path (goto err_fini) would
also skip xe_svm_notifier_unlock() if it were somehow reached with
has_svm_userptr_vmas set, since err_fini only tears down the drm_exec.
Removing the check eliminates both the redundancy and the latent
unwind hazard.

No functional change.

Assisted-by: Claude:claude-opus-4.7
Signed-off-by: Shuicheng Lin <shuicheng.lin@intel.com>
---
 drivers/gpu/drm/xe/xe_vm_madvise.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_vm_madvise.c b/drivers/gpu/drm/xe/xe_vm_madvise.c
index 9e343f9aa44d..38f8321bda10 100644
--- a/drivers/gpu/drm/xe/xe_vm_madvise.c
+++ b/drivers/gpu/drm/xe/xe_vm_madvise.c
@@ -713,12 +713,6 @@ int xe_vm_madvise_ioctl(struct drm_device *dev, void *data, struct drm_file *fil
 
 	attr_type = array_index_nospec(args->type, ARRAY_SIZE(madvise_funcs));
 
-	/* Ensure the madvise function exists for this type */
-	if (!madvise_funcs[attr_type]) {
-		err = -EINVAL;
-		goto err_fini;
-	}
-
 	madvise_funcs[attr_type](xe, vm, madvise_range.vmas, madvise_range.num_vmas, args,
 				 &details);
 
-- 
2.43.0


^ permalink raw reply related	[flat|nested] 8+ messages in thread
end of thread, other threads:[~2026-09-25 15:43 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-09-15  1:12 [PATCH] drm/xe/madvise: Remove unreachable madvise_funcs NULL check Shuicheng Lin
2026-09-15  1:20 ` ✓ CI.KUnit: success for drm/xe/madvise: Remove unreachable madvise_funcs NULL check (rev2) Patchwork
2026-09-15  6:13 ` ✓ Xe.CI.FULL: " Patchwork
2026-09-25 15:43   ` Lin, Shuicheng
2026-09-24 18:30 ` [PATCH] drm/xe/madvise: Remove unreachable madvise_funcs NULL check Wang, X
2026-09-24 20:44   ` Lin, Shuicheng
2026-09-24 22:26     ` Wang, X
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2026-07-08 18:09 Shuicheng Lin

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