[PATCH 5.10 059/142] drm/nouveau/svm: fail NOUVEAU_SVM_INIT ioctl on unsupported devices

Greg Kroah-Hartman
2021-02-02T13:53:57Z

From: Karol Herbst <kherbst@redhat.com>

commit dcd602cc5fe2803bf532d407cde24ba0b7808ff3 upstream.

Fixes a crash when trying to create a channel on e.g. Turing GPUs when
NOUVEAU_SVM_INIT was called before.

Fixes: eeaf06ac1a558 ("drm/nouveau/svm: initial support for shared virtual memory")
Signed-off-by: Karol Herbst <kherbst@redhat.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/gpu/drm/nouveau/nouveau_svm.c | 4 ++++
1 file changed, 4 insertions(+)

--- a/drivers/gpu/drm/nouveau/nouveau_svm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_svm.c
@@ -315,6 +315,10 @@ nouveau_svmm_init(struct drm_device *dev
struct drm_nouveau_svm_init *args = data;
int ret;

+ /* We need to fail if svm is disabled */
+ if (!cli->drm->svm)
+ return -ENOSYS;
+
/* Allocate tracking for SVM-enabled VMM. */
if (!(svmm = kzalloc(sizeof(*svmm), GFP_KERNEL)))
return -ENOMEM;