[Qemu-devel] dataplane: latest rc with selected patches hangs very often

[Andrey Korolyov]

Hello,

is it worthy to re-test dp until next tag point? I am checking aio
with -rc1 and following picked commits (sorry for patchwork
references):

stefanha:
368191 New          [v3,1/4] virtio-blk: avoid dataplane
VirtIOBlockReq early free
368787 New          [v3,2/4] dataplane: do not free VirtQueueElement
in vring_push()
368360 New          [v3,3/4] virtio-blk: avoid g_slice_new0() for
VirtIOBlockReq and VirtQueueElement
368863 New          [v3,4/4] virtio-blk: embed VirtQueueElement in
VirtIOBlockReq

pbonzini:
367551 New          [1/4] block: prefer aio_poll to qemu_aio_wait
367553 New          [2/4] block: drop aio functions that operate on
the main AioContext
367552 New          [3/4] test-aio: fix GSource-based timer test
367554 New          [4/4] AioContext: speed up aio_notify

Emulator itself stop responding in approximately ninety percent of
cases, e.g. it does not react to anything except SIGKILL. Windows VM
is able to read some bits before lockup happens because it draws an
initial logo.

hangs on vl.c:
(gdb) list
2890        g_free(dummy);
2891        if (err) {
2892            qerror_report_err(err);
2893            return -1;
2894        }
2895        return 0;
2896    }
2897
2898    int main(int argc, char **argv, char **envp)
2899    {
(gdb) next
Single stepping until exit from function __lll_lock_wait,
which has no line number information.

cmdline follows:
if=none,id=drive-virtio-disk0,format=raw,cache=writeback,aio=native
... -object iothread,id=blk0 -set device.virtio-disk0.config-wce=off
-set device.virtio-disk0.scsi=off -set
device.virtio-disk0.iothread=blk0