[PATCH 1/1] drm/amdkfd: Handle drain retry fault race with XNACK mode change

[Philip Yang]

Application could change XNACK enabled to disabled while KFD is draining
stall retry fault, the check for whether to drain retry faults must be
before the check for whether xnack_enabled, to avoid report incorrect vm
fault after application changes XNACK mode.

Signed-off-by: Philip Yang <Philip.Yang at amd.com>
---
 drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
index d011d620dfe7..c76d29a22e9d 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
@@ -2700,11 +2700,6 @@ svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,
 		pr_debug("kfd process not founded pasid 0x%x\n", pasid);
 		return 0;
 	}
-	if (!p->xnack_enabled) {
-		pr_debug("XNACK not enabled for pasid 0x%x\n", pasid);
-		r = -EFAULT;
-		goto out;
-	}
 	svms = &p->svms;
 
 	pr_debug("restoring svms 0x%p fault address 0x%llx\n", svms, addr);
@@ -2715,6 +2710,12 @@ svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,
 		goto out;
 	}
 
+	if (!p->xnack_enabled) {
+		pr_debug("XNACK not enabled for pasid 0x%x\n", pasid);
+		r = -EFAULT;
+		goto out;
+	}
+
 	/* p->lead_thread is available as kfd_process_wq_release flush the work
 	 * before releasing task ref.
 	 */
-- 
2.35.1