UPSTREAM: drm/virtio: do NOT reuse resource ids

Bisected guest kernel changes crashing qemu.  Landed at
"6c1cd97bda drm/virtio: fix resource id handling".  Looked again, and
noticed we where not only leaking *some* ids, but *all* ids.  The old
code never ever called virtio_gpu_resource_id_put().

So, commit 6c1cd97bda effectively makes the linux kernel starting
re-using IDs after releasing them, and apparently virglrenderer can't
deal with that.  Oops.

This patch puts a temporary stopgap into place for the 5.0 release.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190208140409.15280-1-kraxel@redhat.com
(cherry picked from commit 16065fcdd19ddb9e093192914ac863884f308766)
Signed-off-by: Greg Hartman <ghartman@google.com>
BUG: 139386237
Change-Id: I606eecad29b877ad5da26dc9e4b5b71d99c8483d
This commit is contained in:
Gerd Hoffmann 2019-02-08 15:04:09 +01:00 committed by Alistair Delva
parent a62c058859
commit 67456f4233

View file

@ -28,10 +28,21 @@
static int virtio_gpu_resource_id_get(struct virtio_gpu_device *vgdev,
uint32_t *resid)
{
#if 0
int handle = ida_alloc(&vgdev->resource_ida, GFP_KERNEL);
if (handle < 0)
return handle;
#else
static int handle;
/*
* FIXME: dirty hack to avoid re-using IDs, virglrenderer
* can't deal with that. Needs fixing in virglrenderer, also
* should figure a better way to handle that in the guest.
*/
handle++;
#endif
*resid = handle + 1;
return 0;
@ -39,7 +50,9 @@ static int virtio_gpu_resource_id_get(struct virtio_gpu_device *vgdev,
static void virtio_gpu_resource_id_put(struct virtio_gpu_device *vgdev, uint32_t id)
{
#if 0
ida_free(&vgdev->resource_ida, id - 1);
#endif
}
static void virtio_gpu_ttm_bo_destroy(struct ttm_buffer_object *tbo)