From: "Alex Bennée" <alex.bennee@linaro.org>
To: qemu-devel@nongnu.org
Cc: slp@redhat.com, mst@redhat.com, marcandre.lureau@redhat.com,
stefanha@redhat.com, mathieu.poirier@linaro.org,
viresh.kumar@linaro.org, sgarzare@redhat.com,
"Alex Bennée" <alex.bennee@linaro.org>
Subject: Re: [PATCH for 7.2-rc? v2 0/5] continuing efforts to fix vhost-user issues
Date: Fri, 25 Nov 2022 19:58:20 +0000 [thread overview]
Message-ID: <87lenyajba.fsf@linaro.org> (raw)
In-Reply-To: <20221125173043.1998075-1-alex.bennee@linaro.org>
Alex Bennée <alex.bennee@linaro.org> writes:
> Hi,
>
<snip>
> I can replicate some of the other failures I've been seeing in CI by
> running:
>
> ../../meson/meson.py test --repeat 10 --print-errorlogs qtest-arm/qos-test
>
> however this seems to run everything in parallel and maybe is better
> at exposing race conditions. Perhaps the CI system makes those races
> easier to hit? Unfortunately I've not been able to figure out exactly
> how things go wrong in the failure case.
>
<snip>
There is a circular call - we are in vu_gpio_stop which triggers a write
to vhost-user which allows us to catch a disconnect event:
#0 vhost_dev_is_started (hdev=0x557adf80d878) at /home/alex/lsrc/qemu.git/include/hw/virtio/vhost.h:199
#1 0x0000557adbe0518a in vu_gpio_stop (vdev=0x557adf80d640) at ../../hw/virtio/vhost-user-gpio.c:138
#2 0x0000557adbe04d56 in vu_gpio_disconnect (dev=0x557adf80d640) at ../../hw/virtio/vhost-user-gpio.c:255
#3 0x0000557adbe049bb in vu_gpio_event (opaque=0x557adf80d640, event=CHR_EVENT_CLOSED) at ../../hw/virtio/vhost-user-gpio.c:274
#4 0x0000557adc0539ef in chr_be_event (s=0x557adea51f10, event=CHR_EVENT_CLOSED) at ../../chardev/char.c:61
#5 0x0000557adc0506aa in qemu_chr_be_event (s=0x557adea51f10, event=CHR_EVENT_CLOSED) at ../../chardev/char.c:81
#6 0x0000557adc04f666 in tcp_chr_disconnect_locked (chr=0x557adea51f10) at ../../chardev/char-socket.c:470
#7 0x0000557adc04c81a in tcp_chr_write (chr=0x557adea51f10, buf=0x7ffe8588cce0 "\v", len=20) at ../../chardev/char-socket.c:129
#8 0x0000557adc050999 in qemu_chr_write_buffer (s=0x557adea51f10, buf=0x7ffe8588cce0 "\v", len=20, offset=0x7ffe8588cbe4, write_all=true) at ../../chardev/char.c:121
#9 0x0000557adc0507c7 in qemu_chr_write (s=0x557adea51f10, buf=0x7ffe8588cce0 "\v", len=20, write_all=true) at ../../chardev/char.c:173
#10 0x0000557adc046f3a in qemu_chr_fe_write_all (be=0x557adf80d830, buf=0x7ffe8588cce0 "\v", len=20) at ../../chardev/char-fe.c:53
#11 0x0000557adbddc02f in vhost_user_write (dev=0x557adf80d878, msg=0x7ffe8588cce0, fds=0x0, fd_num=0) at ../../hw/virtio/vhost-user.c:490
#12 0x0000557adbddd48f in vhost_user_get_vring_base (dev=0x557adf80d878, ring=0x7ffe8588d000) at ../../hw/virtio/vhost-user.c:1260
#13 0x0000557adbdd4bd6 in vhost_virtqueue_stop (dev=0x557adf80d878, vdev=0x557adf80d640, vq=0x557adf843570, idx=0) at ../../hw/virtio/vhost.c:1220
#14 0x0000557adbdd7eda in vhost_dev_stop (hdev=0x557adf80d878, vdev=0x557adf80d640, vrings=false) at ../../hw/virtio/vhost.c:1916
#15 0x0000557adbe051a6 in vu_gpio_stop (vdev=0x557adf80d640) at ../../hw/virtio/vhost-user-gpio.c:142
#16 0x0000557adbe04849 in vu_gpio_set_status (vdev=0x557adf80d640, status=15 '\017') at ../../hw/virtio/vhost-user-gpio.c:173
#17 0x0000557adbdc87ff in virtio_set_status (vdev=0x557adf80d640, val=15 '\017') at ../../hw/virtio/virtio.c:2442
#18 0x0000557adbdcbfa0 in virtio_vmstate_change (opaque=0x557adf80d640, running=false, state=RUN_STATE_SHUTDOWN) at ../../hw/virtio/virtio.c:3736
#19 0x0000557adb91ad27 in vm_state_notify (running=false, state=RUN_STATE_SHUTDOWN) at ../../softmmu/runstate.c:334
#20 0x0000557adb910e88 in do_vm_stop (state=RUN_STATE_SHUTDOWN, send_stop=false) at ../../softmmu/cpus.c:262
#21 0x0000557adb910e30 in vm_shutdown () at ../../softmmu/cpus.c:280
#22 0x0000557adb91b9c3 in qemu_cleanup () at ../../softmmu/runstate.c:827
#23 0x0000557adb522975 in qemu_default_main () at ../../softmmu/main.c:38
#24 0x0000557adb5229a8 in main (argc=27, argv=0x7ffe8588d2f8) at ../../softmmu/main.c:48
(rr) p hdev->started
$9 = true
(rr) info thread
Id Target Id Frame
* 1 Thread 2140414.2140414 (qemu-system-aar) vhost_dev_is_started (hdev=0x557adf80d878) at /home/alex/lsrc/qemu.git/include/hw/virtio/vhost.h:199
2 Thread 2140414.2140439 (qemu-system-aar) 0x0000000070000002 in syscall_traced ()
3 Thread 2140414.2140442 (qemu-system-aar) 0x0000000070000002 in syscall_traced ()
4 Thread 2140414.2140443 (qemu-system-aar) 0x0000000070000002 in syscall_traced ()
During which we eliminate the vhost_dev with a memset:
Thread 1 hit Hardware watchpoint 2: *(unsigned int *) 0x557adf80da30
Old value = 2
New value = 0
__memset_avx2_unaligned_erms () at ../sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S:220
Download failed: Invalid argument. Continuing without source file ./string/../sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S.
220 ../sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S: No such file or directory.
(rr) bt
#0 __memset_avx2_unaligned_erms () at ../sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S:220
#1 0x0000557adbdd67f8 in vhost_dev_cleanup (hdev=0x557adf80d878) at ../../hw/virtio/vhost.c:1501
#2 0x0000557adbe04d68 in vu_gpio_disconnect (dev=0x557adf80d640) at ../../hw/virtio/vhost-user-gpio.c:256
#3 0x0000557adbe049bb in vu_gpio_event (opaque=0x557adf80d640, event=CHR_EVENT_CLOSED) at ../../hw/virtio/vhost-user-gpio.c:274
#4 0x0000557adc0539ef in chr_be_event (s=0x557adea51f10, event=CHR_EVENT_CLOSED) at ../../chardev/char.c:61
#5 0x0000557adc0506aa in qemu_chr_be_event (s=0x557adea51f10, event=CHR_EVENT_CLOSED) at ../../chardev/char.c:81
#6 0x0000557adc04f666 in tcp_chr_disconnect_locked (chr=0x557adea51f10) at ../../chardev/char-socket.c:470
#7 0x0000557adc04c81a in tcp_chr_write (chr=0x557adea51f10, buf=0x7ffe8588cce0 "\v", len=20) at ../../chardev/char-socket.c:129
#8 0x0000557adc050999 in qemu_chr_write_buffer (s=0x557adea51f10, buf=0x7ffe8588cce0 "\v", len=20, offset=0x7ffe8588cbe4, write_all=true) at ../../chardev/char.c:121
#9 0x0000557adc0507c7 in qemu_chr_write (s=0x557adea51f10, buf=0x7ffe8588cce0 "\v", len=20, write_all=true) at ../../chardev/char.c:173
#10 0x0000557adc046f3a in qemu_chr_fe_write_all (be=0x557adf80d830, buf=0x7ffe8588cce0 "\v", len=20) at ../../chardev/char-fe.c:53
#11 0x0000557adbddc02f in vhost_user_write (dev=0x557adf80d878, msg=0x7ffe8588cce0, fds=0x0, fd_num=0) at ../../hw/virtio/vhost-user.c:490
#12 0x0000557adbddd48f in vhost_user_get_vring_base (dev=0x557adf80d878, ring=0x7ffe8588d000) at ../../hw/virtio/vhost-user.c:1260
#13 0x0000557adbdd4bd6 in vhost_virtqueue_stop (dev=0x557adf80d878, vdev=0x557adf80d640, vq=0x557adf843570, idx=0) at ../../hw/virtio/vhost.c:1220
#14 0x0000557adbdd7eda in vhost_dev_stop (hdev=0x557adf80d878, vdev=0x557adf80d640, vrings=false) at ../../hw/virtio/vhost.c:1916
#15 0x0000557adbe051a6 in vu_gpio_stop (vdev=0x557adf80d640) at ../../hw/virtio/vhost-user-gpio.c:142
#16 0x0000557adbe04849 in vu_gpio_set_status (vdev=0x557adf80d640, status=15 '\017') at ../../hw/virtio/vhost-user-gpio.c:173
#17 0x0000557adbdc87ff in virtio_set_status (vdev=0x557adf80d640, val=15 '\017') at ../../hw/virtio/virtio.c:2442
#18 0x0000557adbdcbfa0 in virtio_vmstate_change (opaque=0x557adf80d640, running=false, state=RUN_STATE_SHUTDOWN) at ../../hw/virtio/virtio.c:3736
#19 0x0000557adb91ad27 in vm_state_notify (running=false, state=RUN_STATE_SHUTDOWN) at ../../softmmu/runstate.c:334
#20 0x0000557adb910e88 in do_vm_stop (state=RUN_STATE_SHUTDOWN, send_stop=false) at ../../softmmu/cpus.c:262
#21 0x0000557adb910e30 in vm_shutdown () at ../../softmmu/cpus.c:280
#22 0x0000557adb91b9c3 in qemu_cleanup () at ../../softmmu/runstate.c:827
#23 0x0000557adb522975 in qemu_default_main () at ../../softmmu/main.c:38
#24 0x0000557adb5229a8 in main (argc=27, argv=0x7ffe8588d2f8) at ../../softmmu/main.c:48
Before finally:
#0 __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
#1 0x00007f24dc269537 in __GI_abort () at abort.c:79
#2 0x00007f24dc26940f in __assert_fail_base (fmt=0x7f24dc3e16a8 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=0x557adc28d8f5 "assign || nvqs == proxy->nvqs_with_notifiers", file=0x557adc28d7ab "../../hw/virtio/virtio-pci.c", line=1029, function=<optimized out>) at assert.c:92
#3 0x00007f24dc278662 in __GI___assert_fail (assertion=0x557adc28d8f5 "assign || nvqs == proxy->nvqs_with_notifiers", file=0x557adc28d7ab "../../hw/virtio/virtio-pci.c", line=1029, function=0x557adc28d922 "int virtio_pci_set_guest_notifiers(DeviceState *, int, _Bool)") at assert.c:101
#4 0x0000557adb8e97f1 in virtio_pci_set_guest_notifiers (d=0x557adf805280, nvqs=0, assign=false) at ../../hw/virtio/virtio-pci.c:1029
#5 0x0000557adbe051c7 in vu_gpio_stop (vdev=0x557adf80d640) at ../../hw/virtio/vhost-user-gpio.c:144
#6 0x0000557adbe04849 in vu_gpio_set_status (vdev=0x557adf80d640, status=15 '\017') at ../../hw/virtio/vhost-user-gpio.c:173
#7 0x0000557adbdc87ff in virtio_set_status (vdev=0x557adf80d640, val=15 '\017') at ../../hw/virtio/virtio.c:2442
#8 0x0000557adbdcbfa0 in virtio_vmstate_change (opaque=0x557adf80d640, running=false, state=RUN_STATE_SHUTDOWN) at ../../hw/virtio/virtio.c:3736
#9 0x0000557adb91ad27 in vm_state_notify (running=false, state=RUN_STATE_SHUTDOWN) at ../../softmmu/runstate.c:334
#10 0x0000557adb910e88 in do_vm_stop (state=RUN_STATE_SHUTDOWN, send_stop=false) at ../../softmmu/cpus.c:262
#11 0x0000557adb910e30 in vm_shutdown () at ../../softmmu/cpus.c:280
#12 0x0000557adb91b9c3 in qemu_cleanup () at ../../softmmu/runstate.c:827
#13 0x0000557adb522975 in qemu_default_main () at ../../softmmu/main.c:38
#14 0x0000557adb5229a8 in main (argc=27, argv=0x7ffe8588d2f8) at ../../softmmu/main.c:48
Because of course we've just done that on disconnect.
Not sure what the cleanest way to avoid that is yet. Maybe it will be
clearer on Monday morning.
--
Alex Bennée
next prev parent reply other threads:[~2022-11-25 20:09 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-11-25 17:30 [PATCH for 7.2-rc? v2 0/5] continuing efforts to fix vhost-user issues Alex Bennée
2022-11-25 17:30 ` [PATCH v2 1/5] include/hw: attempt to document VirtIO feature variables Alex Bennée
2022-11-25 17:30 ` [PATCH v2 2/5] include/hw: VM state takes precedence in virtio_device_should_start Alex Bennée
2022-11-27 10:17 ` Bernhard Beschow
2022-11-25 17:30 ` [PATCH v2 3/5] tests/qtests: override "force-legacy" for gpio virtio-mmio tests Alex Bennée
2022-11-25 17:30 ` [PATCH v2 4/5] hw/virtio: ensure a valid host_feature set for virtio-user-gpio Alex Bennée
2022-11-25 17:30 ` [PATCH v2 5/5] vhost: enable vrings in vhost_dev_start() for vhost-user devices Alex Bennée
2022-11-25 18:20 ` [PATCH for 7.2-rc? v2 0/5] continuing efforts to fix vhost-user issues Stefan Weil via
2022-11-25 20:08 ` Alex Bennée
2022-11-25 19:58 ` Alex Bennée [this message]
2022-11-26 9:42 ` Alex Bennée
2022-11-26 11:24 ` Stefan Hajnoczi
2022-11-26 14:12 ` Alex Bennée
2022-11-27 18:04 ` Stefan Hajnoczi
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=87lenyajba.fsf@linaro.org \
--to=alex.bennee@linaro.org \
--cc=marcandre.lureau@redhat.com \
--cc=mathieu.poirier@linaro.org \
--cc=mst@redhat.com \
--cc=qemu-devel@nongnu.org \
--cc=sgarzare@redhat.com \
--cc=slp@redhat.com \
--cc=stefanha@redhat.com \
--cc=viresh.kumar@linaro.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).