Re: [RFC PATCH] virtio: re-order vm_running and use_started checks

[Christian Borntraeger <borntraeger@linux.ibm.com>]

Am 04.11.22 um 17:51 schrieb Christian Borntraeger:
> 
> 
> Am 04.11.22 um 17:14 schrieb Michael S. Tsirkin:
>> On Fri, Nov 04, 2022 at 04:59:35PM +0100, Christian Borntraeger wrote:
>>>
>>>
>>> Am 04.11.22 um 16:56 schrieb Michael S. Tsirkin:
>>>> On Fri, Oct 14, 2022 at 02:21:08PM +0100, Alex Bennée wrote:
>>>>> During migration the virtio device state can be restored before we
>>>>> restart the VM. As no devices can be running while the VM is paused it
>>>>> makes sense to bail out early in that case.
>>>>>
>>>>> This returns the order introduced in:
>>>>>
>>>>>    9f6bcfd99f (hw/virtio: move vm_running check to virtio_device_started)
>>>>>
>>>>> to what virtio-sock was doing longhand.
>>>>>
>>>>> Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
>>>>> Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
>>>>
>>>>
>>>> What happens now:
>>>>
>>>> with this applied I get:
>>>>
>>>> https://gitlab.com/mitsirkin/qemu/-/pipelines/685829158/failures
>>>>
>>>> ――――――――――――――――――――――――――――――――――――― ✀  ―――――――――――――――――――――――――――――――――――――
>>>> stderr:
>>>> qemu-system-arm: Failed to write msg. Wrote -1 instead of 20.
>>>> qemu-system-arm: vhost VQ 0 ring restore failed: -22: Invalid argument (22)
>>>> qemu-system-arm: Failed to set msg fds.
>>>> qemu-system-arm: vhost VQ 1 ring restore failed: -22: Invalid argument (22)
>>>> qemu-system-arm: -chardev socket,id=chr-reconnect,path=/tmp/vhost-test-QLKXU1/reconnect.sock,server=on: info: QEMU waiting for connection on: disconnected:unix:/tmp/vhost-test-QLKXU1/reconnect.sock,server=on
>>>> qemu-system-arm: Failed to write msg. Wrote -1 instead of 20.
>>>> qemu-system-arm: vhost VQ 0 ring restore failed: -22: Invalid argument (22)
>>>> qemu-system-arm: Failed to set msg fds.
>>>> qemu-system-arm: vhost VQ 1 ring restore failed: -22: Invalid argument (22)
>>>> qemu-system-arm: -chardev socket,id=chr-connect-fail,path=/tmp/vhost-test-L9Q6U1/connect-fail.sock,server=on: info: QEMU waiting for connection on: disconnected:unix:/tmp/vhost-test-L9Q6U1/connect-fail.sock,server=on
>>>> qemu-system-arm: -netdev vhost-user,id=hs0,chardev=chr-connect-fail,vhostforce=on: Failed to read msg header. Read 0 instead of 12. Original request 1.
>>>> qemu-system-arm: -netdev vhost-user,id=hs0,chardev=chr-connect-fail,vhostforce=on: vhost_backend_init failed: Protocol error
>>>> qemu-system-arm: -netdev vhost-user,id=hs0,chardev=chr-connect-fail,vhostforce=on: failed to init vhost_net for queue 0
>>>> qemu-system-arm: -netdev vhost-user,id=hs0,chardev=chr-connect-fail,vhostforce=on: info: QEMU waiting for connection on: disconnected:unix:/tmp/vhost-test-L9Q6U1/connect-fail.sock,server=on
>>>> qemu-system-arm: Failed to write msg. Wrote -1 instead of 20.
>>>> qemu-system-arm: vhost VQ 0 ring restore failed: -22: Invalid argument (22)
>>>> qemu-system-arm: Failed to set msg fds.
>>>> qemu-system-arm: vhost VQ 1 ring restore failed: -22: Invalid argument (22)
>>>> qemu-system-arm: -chardev socket,id=chr-flags-mismatch,path=/tmp/vhost-test-3MO5U1/flags-mismatch.sock,server=on: info: QEMU waiting for connection on: disconnected:unix:/tmp/vhost-test-3MO5U1/flags-mismatch.sock,server=on
>>>> qemu-system-arm: Failed to write msg. Wrote -1 instead of 52.
>>>> qemu-system-arm: vhost_set_mem_table failed: Invalid argument (22)
>>>> qemu-system-arm: unable to start vhost net: 22: falling back on userspace virtio
>>>> vhost lacks feature mask 0x40000000 for backend
>>>> qemu-system-arm: failed to init vhost_net for queue 0
>>>> qemu-system-arm: Failed to set msg fds.
>>>> qemu-system-arm: vhost VQ 0 ring restore failed: -22: Invalid argument (22)
>>>> qemu-system-arm: Failed to set msg fds.
>>>> qemu-system-arm: vhost VQ 1 ring restore failed: -22: Invalid argument (22)
>>>> qemu-system-arm: Failed to write msg. Wrote -1 instead of 20.
>>>> qemu-system-arm: vhost VQ 0 ring restore failed: -22: Invalid argument (22)
>>>> qemu-system-arm: Failed to set msg fds.
>>>> qemu-system-arm: vhost VQ 1 ring restore failed: -22: Invalid argument (22)
>>>> qemu-system-arm: Failed to set msg fds.
>>>> qemu-system-arm: vhost VQ 2 ring restore failed: -22: Invalid argument (22)
>>>> qemu-system-arm: Failed to set msg fds.
>>>> qemu-system-arm: vhost VQ 3 ring restore failed: -22: Invalid argument (22)
>>>> qemu-system-arm: Failed to write msg. Wrote -1 instead of 20.
>>>> qemu-system-arm: vhost VQ 0 ring restore failed: -22: Invalid argument (22)
>>>> qemu-system-arm: Failed to set msg fds.
>>>> qemu-system-arm: vhost VQ 1 ring restore failed: -22: Invalid argument (22)
>>>> qemu-system-arm: Failed to write msg. Wrote -1 instead of 20.
>>>> qemu-system-arm: vhost VQ 0 ring restore failed: -22: Invalid argument (22)
>>>> qemu-system-arm: Failed to set msg fds.
>>>> qemu-system-arm: vhost VQ 1 ring restore failed: -22: Invalid argument (22)
>>>> qemu-system-arm: Failed to set msg fds.
>>>> qemu-system-arm: vhost VQ 0 ring restore failed: -22: Invalid argument (22)
>>>> qemu-system-arm: Failed to set msg fds.
>>>> qemu-system-arm: vhost VQ 1 ring restore failed: -22: Invalid argument (22)
>>>> qemu-system-arm: Failed to set msg fds.
>>>> qemu-system-arm: vhost_set_vring_call failed: Invalid argument (22)
>>>> qemu-system-arm: Failed to set msg fds.
>>>> qemu-system-arm: vhost_set_vring_call failed: Invalid argument (22)
>>>> qemu-system-arm: Failed to write msg. Wrote -1 instead of 20.
>>>> qemu-system-arm: vhost VQ 0 ring restore failed: -5: Input/output error (5)
>>>> qemu-system-arm: ../hw/virtio/virtio-bus.c:211: void virtio_bus_release_ioeventfd(VirtioBusState *): Assertion `bus->ioeventfd_grabbed != 0' failed.
>>>> ../tests/qtest/libqtest.c:188: kill_qemu() detected QEMU death from signal 6 (Aborted) (core dumped)
>>>> **
>>>> ERROR:../tests/qtest/qos-test.c:191:subprocess_run_one_test: child process (/arm/virt/virtio-mmio/virtio-bus/vhost-user-gpio-device/vhost-user-gpio/vhost-user-gpio-tests/read-guest-mem/memfile/subprocess [8735]) failed unexpectedly
>>>> (test program exited with status code -6)
>>>> ――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――
>>>>
>>>>
>>>>
>>>>
>>>> without this it passes:
>>>>
>>>> https://gitlab.com/mitsirkin/qemu/-/jobs/3275949777
>>>>
>>>>
>>>> this only triggers under github, clang-system job.
>>>> trying to decide what to do now. revert just this?
>>> When we revert this save/restore for vsock is broken. Not sure, maybe we must use a more fine-grained fix as outlined in my initial mail?
>>
>>
>>
>> Could you take a look here pls?
>>
>> https://gitlab.com/mitsirkin/qemu/-/tree/testrevert1
> 
> I kicked of our regression test suite for s390.

This branch also seems to fix my original problem.
Regression is still running but looks good so far.