This is a note to let you know that I've just added the patch titled
drm/amdgpu: fix tear down order in amdgpu_vm_pt_free
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-amdgpu-fix-tear-down-order-in-amdgpu_vm_pt_free.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From ceb9a321e7639700844aa3bf234a4e0884f13b77 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christian=20K=C3=B6nig?= <christian.koenig@xxxxxxx>
Date: Fri, 8 Dec 2023 13:43:09 +0100
Subject: drm/amdgpu: fix tear down order in amdgpu_vm_pt_free
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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From: Christian König <christian.koenig@xxxxxxx>
commit ceb9a321e7639700844aa3bf234a4e0884f13b77 upstream.
When freeing PD/PT with shadows it can happen that the shadow
destruction races with detaching the PD/PT from the VM causing a NULL
pointer dereference in the invalidation code.
Fix this by detaching the the PD/PT from the VM first and then
freeing the shadow instead.
Signed-off-by: Christian König <christian.koenig@xxxxxxx>
Fixes: https://gitlab.freedesktop.org/drm/amd/-/issues/2867
Cc: <stable@xxxxxxxxxxxxxxx>
Reviewed-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c
@@ -642,13 +642,14 @@ static void amdgpu_vm_pt_free(struct amd
if (!entry->bo)
return;
+
+ entry->bo->vm_bo = NULL;
shadow = amdgpu_bo_shadowed(entry->bo);
if (shadow) {
ttm_bo_set_bulk_move(&shadow->tbo, NULL);
amdgpu_bo_unref(&shadow);
}
ttm_bo_set_bulk_move(&entry->bo->tbo, NULL);
- entry->bo->vm_bo = NULL;
spin_lock(&entry->vm->status_lock);
list_del(&entry->vm_status);
Patches currently in stable-queue which might be from christian.koenig@xxxxxxx are
queue-6.6/drm-amdgpu-fix-tear-down-order-in-amdgpu_vm_pt_free.patch
queue-6.6/drm-amdgpu-sdma5.2-add-begin-end_use-ring-callbacks.patch
