[PATCH 6.6 202/396] drm/nouveau: fix stale locked mutex in nouveau_gem_ioctl_pushbuf

Greg Kroah-Hartman
2024-04-01T16:45:53Z

From: Karol Herbst <kherbst@redhat.com>

commit daf8739c3322a762ce84f240f50e0c39181a41ab upstream.

If VM_BIND is enabled on the client the legacy submission ioctl can't be
used, however if a client tries to do so regardless it will return an
error. In this case the clients mutex remained unlocked leading to a
deadlock inside nouveau_drm_postclose or any other nouveau ioctl call.

Fixes: b88baab82871 ("drm/nouveau: implement new VM_BIND uAPI")
Cc: Danilo Krummrich <dakr@redhat.com>
Cc: <stable@vger.kernel.org> # v6.6+
Signed-off-by: Karol Herbst <kherbst@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Danilo Krummrich <dakr@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240305133853.2214268-1-kherbst@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/gpu/drm/nouveau/nouveau_gem.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/gpu/drm/nouveau/nouveau_gem.c
+++ b/drivers/gpu/drm/nouveau/nouveau_gem.c
@@ -758,7 +758,7 @@ nouveau_gem_ioctl_pushbuf(struct drm_dev
return -ENOMEM;

if (unlikely(nouveau_cli_uvmm(cli)))
- return -ENOSYS;
+ return nouveau_abi16_put(abi16, -ENOSYS);

list_for_each_entry(temp, &abi16->channels, head) {
if (temp->chan->chid == req->channel) {