[Qemu-devel] virtio-blk-test failure

[John Snow <jsnow@redhat.com>]

I've been seeing this failure pop up very occasionally and I can usually 
get the test to pass again by just re-running, but every now and again:

GTESTER check-qtest-x86_64
blkdebug: Suspended request 'A'
blkdebug: Resuming request 'A'
main-loop: WARNING: I/O thread spun for 1000 iterations
main-loop: WARNING: I/O thread spun for 1000 iterations
**
ERROR:/home/bos/jhuston/src/qemu/tests/libqos/virtio.c:91:qvirtio_wait_queue_isr: 
assertion failed: (g_get_monotonic_time() - start_time <= timeout_us)
GTester: last random seed: R02S3ba253e130ac76bbcb0bade0a2d54b2f
[vmxnet3][WR][vmxnet3_peer_has_vnet_hdr]: Peer has no virtio extension. 
Task offloads will be emulated.
make: *** [check-qtest-x86_64] Error 1


I wrote a test loop that runs virtio-blk-test over and over again in a 
loop and saw it fail after 137 runs.

It looks like the culprit is /virtio/blk/pci/msix; if you run only that 
test it could take anywhere from 20-250 runs before you see it fail.

I only did a little bit of debugging, but the QMP command that 
immediately precedes the wait_config_isr call here appears to execute 
successfully.

Any hunches, Marc?