The removed line prevents the following cleanup function
to execute a dma_fence_put on the out_fence to free its
memory, producing the following output in kmemleak:
unreferenced object 0xffff888126d8ee00 (size 128):
comm "kwin_wayland", pid 981, jiffies 4295380296 (age 390.060s)
hex dump (first 32 bytes):
c8 a1 c2 27 81 88 ff ff e0 14 a9 c0 ff ff ff ff ...'............
30 1a e1 2e a6 00 00 00 28 fc 5b 17 81 88 ff ff 0.......(.[.....
backtrace:
[<0000000011655661>] kmalloc_trace+0x26/0xa0
[<0000000055f15b82>] virtio_gpu_fence_alloc+0x47/0xc0 [virtio_gpu]
[<00000000fa6d96f9>] virtio_gpu_execbuffer_ioctl+0x1a8/0x800 [virtio_gpu]
[<00000000e6cb5105>] drm_ioctl_kernel+0x169/0x240 [drm]
[<000000005ad33e27>] drm_ioctl+0x399/0x6b0 [drm]
[<00000000a19dbf65>] __x64_sys_ioctl+0xc5/0x100
[<0000000011fa801e>] do_syscall_64+0x5b/0xc0
[<0000000065c76d8a>] entry_SYSCALL_64_after_hwframe+0x6e/0xd8
unreferenced object 0xffff888121930500 (size 128):
comm "kwin_wayland", pid 981, jiffies 4295380313 (age 390.096s)
hex dump (first 32 bytes):
c8 a1 c2 27 81 88 ff ff e0 14 a9 c0 ff ff ff ff ...'............
f9 ec d7 2f a6 00 00 00 28 fc 5b 17 81 88 ff ff .../....(.[.....
backtrace:
[<0000000011655661>] kmalloc_trace+0x26/0xa0
[<0000000055f15b82>] virtio_gpu_fence_alloc+0x47/0xc0 [virtio_gpu]
[<00000000fa6d96f9>] virtio_gpu_execbuffer_ioctl+0x1a8/0x800 [virtio_gpu]
[<00000000e6cb5105>] drm_ioctl_kernel+0x169/0x240 [drm]
[<000000005ad33e27>] drm_ioctl+0x399/0x6b0 [drm]
[<00000000a19dbf65>] __x64_sys_ioctl+0xc5/0x100
[<0000000011fa801e>] do_syscall_64+0x5b/0xc0
[<0000000065c76d8a>] entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[...]
This memleak will grow quickly, being possible to see the
following line in dmesg after few minutes of life in the
virtual machine:
[ 706.217388] kmemleak: 10731 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
The patch will remove the line to allow the cleanup
function do its job.
Signed-off-by: José Pekkarinen <jose.pekkarinen@foxhound.fi>
Fixes: e4812ab8e6 ("drm/virtio: Refactor and optimize job submission code path")
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230912060824.5210-1-jose.pekkarinen@foxhound.fi
We don't want to create a fence for every command submission. It's
only necessary when userspace provides a waitable token for submission.
This could be:
1) bo_handles, to be used with VIRTGPU_WAIT
2) out_fence_fd, to be used with dma_fence apis
3) a ring_idx provided with VIRTGPU_CONTEXT_PARAM_POLL_RINGS_MASK
+ DRM event API
4) syncobjs in the future
The use case for just submitting a command to the host, and expecting
no response. For example, gfxstream has GFXSTREAM_CONTEXT_PING that
just wakes up the host side worker threads. There's also
CROSS_DOMAIN_CMD_SEND which just sends data to the Wayland server.
This prevents the need to signal the automatically created
virtio_gpu_fence.
In addition, VIRTGPU_EXECBUF_RING_IDX is checked when creating a
DRM event object. VIRTGPU_CONTEXT_PARAM_POLL_RINGS_MASK is
already defined in terms of per-context rings. It was theoretically
possible to create a DRM event on the global timeline (ring_idx == 0),
if the context enabled DRM event polling. However, that wouldn't
work and userspace (Sommelier). Explicitly disallow it for
clarity.
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Reviewed-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Tested-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> # edited coding style
Link: https://patchwork.freedesktop.org/patch/msgid/20230707213124.494-1-gurchetansingh@chromium.org