Re: [PULL 00/18] migration queue

[Peter Maydell]

On Mon, 14 Mar 2022 at 18:58, Peter Maydell <peter.maydell@linaro.org> wrote:
>
> On Mon, 14 Mar 2022 at 17:15, Peter Maydell <peter.maydell@linaro.org> wrote:
> >
> > On Mon, 14 Mar 2022 at 17:07, Daniel P. Berrangé <berrange@redhat.com> 
> > wrote:
> > > So the test harness is waiting for a reply to 'query-migrate'.
> > >
> > > This should be fast unless QEMU has hung in the main event
> > > loop servicing monitor commands, or stopped.
> >
> > I was kind of loose with the terminology -- I don't remember whether
> > it was actually hung in the sense of stopped entirely, or just
> > "sat in a loop waiting for a migration state that never arrives".
> > I'll try to look more closely if I can catch it in the act again.
>
> I just hit the abort case, narrowing it down to the
> /i386/migration/multifd/tcp/zlib case, which can hit this without
> any other tests being run:

> This test seems to fail fairly frequently. I'll try a bisect...

On this s390 machine, this test has been intermittent since
it was first added in commit 7ec2c2b3c1 ("multifd: Add zlib compression
multifd support") in 2019. On that commit (after 31 successful
runs):

# random seed: R02S17937f515046216afcc72143266b3e1f
# Start of i386 tests
# Start of migration tests
# Start of multifd tests
# Start of tcp tests
# starting QEMU: exec ./build/i386/i386-softmmu/qemu-system-i386
-qtest unix:/tmp/qtest-861747.sock -qtest-log /dev/null -chardev
socket,path=/tmp/qtest-861747.qmp,id=char0 -mon
chardev=char0,mode=control -display none -accel kvm -accel tcg -name
source,debug-threads=on -m 150M -serial
file:/tmp/migration-test-7qODSs/src_serial -drive
file=/tmp/migration-test-7qODSs/bootsect,format=raw    -accel qtest
qemu-system-i386: -accel kvm: invalid accelerator kvm
qemu-system-i386: falling back to tcg
# starting QEMU: exec ./build/i386/i386-softmmu/qemu-system-i386
-qtest unix:/tmp/qtest-861747.sock -qtest-log /dev/null -chardev
socket,path=/tmp/qtest-861747.qmp,id=char0 -mon
chardev=char0,mode=control -display none -accel kvm -accel tcg -name
target,debug-threads=on -m 150M -serial
file:/tmp/migration-test-7qODSs/dest_serial -incoming defer -drive
file=/tmp/migration-test-7qODSs/bootsect,format=raw    -accel qtest
qemu-system-i386: -accel kvm: invalid accelerator kvm
qemu-system-i386: falling back to tcg
Memory content inconsistency at 5cff000 first_byte = 2 last_byte = 1
current = 0 hit_edge = 1
Memory content inconsistency at 5d00000 first_byte = 2 last_byte = 1
current = 0 hit_edge = 1
Memory content inconsistency at 5d01000 first_byte = 2 last_byte = 1
current = 0 hit_edge = 1
Memory content inconsistency at 5d02000 first_byte = 2 last_byte = 1
current = 0 hit_edge = 1
Memory content inconsistency at 5d03000 first_byte = 2 last_byte = 1
current = 0 hit_edge = 1
Memory content inconsistency at 5d04000 first_byte = 2 last_byte = 1
current = 0 hit_edge = 1
Memory content inconsistency at 5d05000 first_byte = 2 last_byte = 1
current = 0 hit_edge = 1
Memory content inconsistency at 5d06000 first_byte = 2 last_byte = 1
current = 0 hit_edge = 1
Memory content inconsistency at 5d07000 first_byte = 2 last_byte = 1
current = 0 hit_edge = 1
Memory content inconsistency at 5d08000 first_byte = 2 last_byte = 1
current = 0 hit_edge = 1
and in another 118 pages**
ERROR:/home/linux1/qemu/tests/qtest/migration-test.c:268:check_guests_ram:
assertion failed: (bad == 0)
Bail out! 
ERROR:/home/linux1/qemu/tests/qtest/migration-test.c:268:check_guests_ram:
assertion failed: (bad == 0)
Aborted (core dumped)

-- PMM