Three small fixes for virtio-gpu, each independent:

1. Add resource validation to CTX_ATTACH/DETACH_RESOURCE handlers,
   resolving the long-standing "TODO add security" comments.

2. Replace three fprintf(stderr) calls with qemu_log_mask(LOG_GUEST_ERROR)
   and trace events, consistent with the rest of the virtio-gpu code.

3. Use unsigned shift (1U <<) for scanout_bitmask operations to avoid
   undefined behavior when the shift count could theoretically reach 31.

Bin Guo (3):
  virtio-gpu-virgl: validate resource existence on ctx attach/detach
  virtio-gpu-virgl: replace fprintf(stderr) with qemu_log_mask and trace
    events
  virtio-gpu: use unsigned shift for scanout bitmask operations

 hw/display/trace-events       |  2 ++
 hw/display/virtio-gpu-virgl.c | 33 +++++++++++++++++++++++----------
 hw/display/virtio-gpu.c       | 12 ++++++------
 3 files changed, 31 insertions(+), 16 deletions(-)

-- 
2.50.1 (Apple Git-155)