VirtIO-GPU commands may be processed outside of main-loop, from a CPU
thread. This results in GL context switch failure because context is held
by main-loop thread when GL is invoked from CPU thread. Always release GL
context after performing GL operations such that other threads could take
over the context.
0 SDL_GL_MakeCurrent() (libSDL3)
1 SDL_GL_MakeCurrent_REAL() (libSDL2)
2 sdl2_gl_make_context_current() (ui/sdl2-gl.c:201)
3 make_current() (virglrenderer.c:639)
4 vrend_finish_context_switch() (vrend_renderer.c:11630)
5 vrend_hw_switch_context() (vrend_renderer.c:11613)
6 vrend_renderer_force_ctx_0() (vrend_renderer.c:12986)
7 virgl_renderer_force_ctx_0() (virglrenderer.c:460)
8 virtio_gpu_virgl_process_cmd() (virtio-gpu-virgl.c:1013)
9 virtio_gpu_process_cmdq() (virtio-gpu.c:1050)
10 virtio_gpu_gl_handle_ctrl() (virtio-gpu-gl.c:86)
11 aio_bh_poll() (util/async.c)
12 aio_poll() (util/aio-posix.c)
13 blk_pwrite() (block/block-gen.c:1985)
14 pflash_update() (pflash_cfi01.c:396)
15 pflash_write() (pflash_cfi01.c:541)
16 memory_region_dispatch_write() (system/memory.c:1554)
17 flatview_write() (system/physmem.c:3333)
18 address_space_write() (system/physmem.c:3453)
19 kvm_cpu_exec() (accel/kvm/kall-all.c:3248)
20 kvm_vcpu_thread_fn() (accel/kvm/kaccel-ops.c:53)
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
---
hw/display/virtio-gpu-virgl.c | 22 +++++++++++++++++++---
1 file changed, 19 insertions(+), 3 deletions(-)
diff --git a/hw/display/virtio-gpu-virgl.c b/hw/display/virtio-gpu-virgl.c
index 0f754829fb71..0021df45d4b2 100644
--- a/hw/display/virtio-gpu-virgl.c
+++ b/hw/display/virtio-gpu-virgl.c
@@ -896,14 +896,20 @@ static void virgl_cmd_set_scanout_blob(VirtIOGPU *g,
}
#endif
-void virtio_gpu_virgl_process_cmd(VirtIOGPU *g,
- struct virtio_gpu_ctrl_command *cmd)
+static void virtio_gpu_virgl_unset_ctx_0(VirtIOGPU *g)
+{
+ /* Virglrender always uses first scanout for GL. */
+ dpy_gl_ctx_make_current(g->parent_obj.scanout[0].con, NULL);
+}
+
+static void
+virtio_gpu_virgl_process_cmd_with_ctx_0(VirtIOGPU *g,
+ struct virtio_gpu_ctrl_command *cmd)
{
bool cmd_suspended = false;
VIRTIO_GPU_FILL_CMD(cmd->cmd_hdr);
- virgl_renderer_force_ctx_0();
switch (cmd->cmd_hdr.type) {
case VIRTIO_GPU_CMD_CTX_CREATE:
virgl_cmd_context_create(g, cmd);
@@ -1010,6 +1016,14 @@ void virtio_gpu_virgl_process_cmd(VirtIOGPU *g,
virgl_renderer_create_fence(cmd->cmd_hdr.fence_id, cmd->cmd_hdr.type);
}
+void virtio_gpu_virgl_process_cmd(VirtIOGPU *g,
+ struct virtio_gpu_ctrl_command *cmd)
+{
+ virgl_renderer_force_ctx_0();
+ virtio_gpu_virgl_process_cmd_with_ctx_0(g, cmd);
+ virtio_gpu_virgl_unset_ctx_0(g);
+}
+
static void virgl_write_fence(void *opaque, uint32_t fence)
{
VirtIOGPU *g = opaque;
@@ -1136,8 +1150,10 @@ static void virtio_gpu_fence_poll(void *opaque)
VirtIOGPU *g = opaque;
VirtIOGPUGL *gl = VIRTIO_GPU_GL(g);
+ virgl_renderer_force_ctx_0();
virgl_renderer_poll();
virtio_gpu_process_cmdq(g);
+ virtio_gpu_virgl_unset_ctx_0(g);
if (!QTAILQ_EMPTY(&g->cmdq) || !QTAILQ_EMPTY(&g->fenceq)) {
timer_mod(gl->fence_poll, qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + 10);
}
--
2.52.0