6.6-stable review patch. If anyone has any objections, please let me know.
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From: Christian König christian.koenig@amd.com
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@amd.com Fixes: https://gitlab.freedesktop.org/drm/amd/-/issues/2867 Cc: stable@vger.kernel.org Reviewed-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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);