Re: [Qemu-devel] master: intermittent acpi-test failures

[Michael S. Tsirkin]

On Wed, May 28, 2014 at 12:29:43PM +0100, Peter Maydell wrote:
> On 27 May 2014 22:38, Peter Maydell <address@hidden> wrote:
> > I'm seeing this test failure intermittently on 'make check':
> >
> > ERROR:/root/qemu/tests/acpi-test.c:618:test_acpi_one: assertion failed
> > (signature == SIGNATURE): (0x00000000 == 0x0000dead)
> > GTester: last random seed: R02S8d0d60963e4442ce284a81d20ce32053
> >
> > (32 bit ARM host, in case that makes a difference.)
> >
> > Any ideas? It looks from the test as if this may just be
> > that the test is coded to assume a faster machine, which
> > is a bit unfortunate.
> 
> Well, I put some diagnostic printing in, and it looks like that
> guess was wrong. Most of the time we complete well within
> the timeout limit for the test:
> 
> TEST: tests/acpi-test... (pid=10639)
>   /i386/acpi/tcg:
> ........ : looped for 8 cycles total (limit 600)
> main-loop: WARNING: I/O thread spun for 1000 iterations
> ......... : looped for 9 cycles total (limit 600)
> main-loop: WARNING: I/O thread spun for 1000 iterations
> OK
> PASS: tests/acpi-test
> 
> But occasionally we don't:
> 
> TEST: tests/acpi-test... (pid=10679)
>   /i386/acpi/tcg:
> ........ : looped for 8 cycles total (limit 600)
> main-loop: WARNING: I/O thread spun for 1000 iterations
> ........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
> : looped for 600 cycles total (limit 600)
> **
> ERROR:/root/qemu/tests/acpi-test.c:620:test_acpi_one: assertion failed
> (signature == SIGNATURE): (0x00000000 == 0x0000dead)
> FAIL
> GTester: last random seed: R02S1fd7be17c4dc962a399b016f9153e15a
> (pid=10688)
> FAIL: tests/acpi-test
> 
> thanks
> -- PMM

I suspect a memory ordering issue.
Looking at it.

-- 
MST