| Message ID | 1563696502-7972-1-git-send-email-lizhengui@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] virtio-scsi: fixed virtio_scsi_ctx_check failed when detaching scsi disk | expand |
On 21/07/19 10:08, l00284672 wrote: > commit a6f230c move blockbackend back to main AioContext on unplug. It set the AioContext of > SCSIDevice to the main AioContex, but s->ctx is still the iothread AioContex（if the scsi controller > is configure with iothread）. So if there are having in-flight requests during unplug, a failing assertion > happend. The bt is below: > (gdb) bt > #0 0x0000ffff86aacbd0 in raise () from /lib64/libc.so.6 > #1 0x0000ffff86aadf7c in abort () from /lib64/libc.so.6 > #2 0x0000ffff86aa6124 in __assert_fail_base () from /lib64/libc.so.6 > #3 0x0000ffff86aa61a4 in __assert_fail () from /lib64/libc.so.6 > #4 0x0000000000529118 in virtio_scsi_ctx_check (d=<optimized out>, s=<optimized out>, s=<optimized out>) at /home/qemu-4.0.0/hw/scsi/virtio-scsi.c:246 > #5 0x0000000000529ec4 in virtio_scsi_handle_cmd_req_prepare (s=0x2779ec00, req=0xffff740397d0) at /home/qemu-4.0.0/hw/scsi/virtio-scsi.c:559 > #6 0x000000000052a228 in virtio_scsi_handle_cmd_vq (s=0x2779ec00, vq=0xffff7c6d7110) at /home/qemu-4.0.0/hw/scsi/virtio-scsi.c:603 > #7 0x000000000052afa8 in virtio_scsi_data_plane_handle_cmd (vdev=<optimized out>, vq=0xffff7c6d7110) at /home/qemu-4.0.0/hw/scsi/virtio-scsi-dataplane.c:59 > #8 0x000000000054d94c in virtio_queue_host_notifier_aio_poll (opaque=<optimized out>) at /home/qemu-4.0.0/hw/virtio/virtio.c:2452 > > assert(blk_get_aio_context(d->conf.blk) == s->ctx) failed. > > To avoid assertion failed, moving the "if" after qdev_simple_device_unplug_cb. > > In addition, to avoid another qemu crash below, add aio_disable_external before > qdev_simple_device_unplug_cb, which disable the further processing of external clients > when doing qdev_simple_device_unplug_cb. > (gdb) bt > #0 scsi_req_unref (req=0xffff6802c6f0) at hw/scsi/scsi-bus.c:1283 > #1 0x00000000005294a4 in virtio_scsi_handle_cmd_req_submit (req=<optimized out>, > s=<optimized out>) at /home/qemu-4.0.0/hw/scsi/virtio-scsi.c:589 > #2 0x000000000052a2a8 in virtio_scsi_handle_cmd_vq (s=s@entry=0x9c90e90, > vq=vq@entry=0xffff7c05f110) at /home/qemu-4.0.0/hw/scsi/virtio-scsi.c:625 > #3 0x000000000052afd8 in virtio_scsi_data_plane_handle_cmd (vdev=<optimized out>, > vq=0xffff7c05f110) at /home/qemu-4.0.0/hw/scsi/virtio-scsi-dataplane.c:60 > #4 0x000000000054d97c in virtio_queue_host_notifier_aio_poll (opaque=<optimized out>) > at /home/qemu-4.0.0/hw/virtio/virtio.c:2447 > #5 0x00000000009b204c in run_poll_handlers_once (ctx=ctx@entry=0x6efea40, > timeout=timeout@entry=0xffff7d7f7308) at util/aio-posix.c:521 > #6 0x00000000009b2b64 in run_poll_handlers (ctx=ctx@entry=0x6efea40, > max_ns=max_ns@entry=4000, timeout=timeout@entry=0xffff7d7f7308) at util/aio-posix.c:559 > #7 0x00000000009b2ca0 in try_poll_mode (ctx=ctx@entry=0x6efea40, timeout=0xffff7d7f7308, > timeout@entry=0xffff7d7f7348) at util/aio-posix.c:594 > #8 0x00000000009b31b8 in aio_poll (ctx=0x6efea40, blocking=blocking@entry=true) > at util/aio-posix.c:636 > #9 0x00000000006973cc in iothread_run (opaque=0x6ebd800) at iothread.c:75 > #10 0x00000000009b592c in qemu_thread_start (args=0x6efef60) at util/qemu-thread-posix.c:502 > #11 0x0000ffff8057f8bc in start_thread () from /lib64/libpthread.so.0 > #12 0x0000ffff804e5f8c in thread_start () from /lib64/libc.so.6 > (gdb) p bus > $1 = (SCSIBus *) 0x0 > > Signed-off-by: Zhengui li <lizhengui@huawei.com> > --- > hw/scsi/virtio-scsi.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c > index 839f120..79e555f 100644 > --- a/hw/scsi/virtio-scsi.c > +++ b/hw/scsi/virtio-scsi.c > @@ -837,13 +837,15 @@ static void virtio_scsi_hotunplug(HotplugHandler *hotplug_dev, DeviceState *dev, > virtio_scsi_release(s); > } > > + aio_disable_external(s->ctx); > + qdev_simple_device_unplug_cb(hotplug_dev, dev, errp); > + aio_enable_external(s->ctx); > + > if (s->ctx) { > virtio_scsi_acquire(s); > blk_set_aio_context(sd->conf.blk, qemu_get_aio_context()); > virtio_scsi_release(s); > } > - > - qdev_simple_device_unplug_cb(hotplug_dev, dev, errp); > } > > static struct SCSIBusInfo virtio_scsi_scsi_info = { > Queued, thanks. Paolo
diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c index 839f120..79e555f 100644 --- a/hw/scsi/virtio-scsi.c +++ b/hw/scsi/virtio-scsi.c @@ -837,13 +837,15 @@ static void virtio_scsi_hotunplug(HotplugHandler *hotplug_dev, DeviceState *dev, virtio_scsi_release(s); } + aio_disable_external(s->ctx); + qdev_simple_device_unplug_cb(hotplug_dev, dev, errp); + aio_enable_external(s->ctx); + if (s->ctx) { virtio_scsi_acquire(s); blk_set_aio_context(sd->conf.blk, qemu_get_aio_context()); virtio_scsi_release(s); } - - qdev_simple_device_unplug_cb(hotplug_dev, dev, errp); } static struct SCSIBusInfo virtio_scsi_scsi_info = {
commit a6f230c move blockbackend back to main AioContext on unplug. It set the AioContext of SCSIDevice to the main AioContex, but s->ctx is still the iothread AioContex（if the scsi controller is configure with iothread）. So if there are having in-flight requests during unplug, a failing assertion happend. The bt is below: (gdb) bt #0 0x0000ffff86aacbd0 in raise () from /lib64/libc.so.6 #1 0x0000ffff86aadf7c in abort () from /lib64/libc.so.6 #2 0x0000ffff86aa6124 in __assert_fail_base () from /lib64/libc.so.6 #3 0x0000ffff86aa61a4 in __assert_fail () from /lib64/libc.so.6 #4 0x0000000000529118 in virtio_scsi_ctx_check (d=<optimized out>, s=<optimized out>, s=<optimized out>) at /home/qemu-4.0.0/hw/scsi/virtio-scsi.c:246 #5 0x0000000000529ec4 in virtio_scsi_handle_cmd_req_prepare (s=0x2779ec00, req=0xffff740397d0) at /home/qemu-4.0.0/hw/scsi/virtio-scsi.c:559 #6 0x000000000052a228 in virtio_scsi_handle_cmd_vq (s=0x2779ec00, vq=0xffff7c6d7110) at /home/qemu-4.0.0/hw/scsi/virtio-scsi.c:603 #7 0x000000000052afa8 in virtio_scsi_data_plane_handle_cmd (vdev=<optimized out>, vq=0xffff7c6d7110) at /home/qemu-4.0.0/hw/scsi/virtio-scsi-dataplane.c:59 #8 0x000000000054d94c in virtio_queue_host_notifier_aio_poll (opaque=<optimized out>) at /home/qemu-4.0.0/hw/virtio/virtio.c:2452 assert(blk_get_aio_context(d->conf.blk) == s->ctx) failed. To avoid assertion failed, moving the "if" after qdev_simple_device_unplug_cb. In addition, to avoid another qemu crash below, add aio_disable_external before qdev_simple_device_unplug_cb, which disable the further processing of external clients when doing qdev_simple_device_unplug_cb. (gdb) bt #0 scsi_req_unref (req=0xffff6802c6f0) at hw/scsi/scsi-bus.c:1283 #1 0x00000000005294a4 in virtio_scsi_handle_cmd_req_submit (req=<optimized out>, s=<optimized out>) at /home/qemu-4.0.0/hw/scsi/virtio-scsi.c:589 #2 0x000000000052a2a8 in virtio_scsi_handle_cmd_vq (s=s@entry=0x9c90e90, vq=vq@entry=0xffff7c05f110) at /home/qemu-4.0.0/hw/scsi/virtio-scsi.c:625 #3 0x000000000052afd8 in virtio_scsi_data_plane_handle_cmd (vdev=<optimized out>, vq=0xffff7c05f110) at /home/qemu-4.0.0/hw/scsi/virtio-scsi-dataplane.c:60 #4 0x000000000054d97c in virtio_queue_host_notifier_aio_poll (opaque=<optimized out>) at /home/qemu-4.0.0/hw/virtio/virtio.c:2447 #5 0x00000000009b204c in run_poll_handlers_once (ctx=ctx@entry=0x6efea40, timeout=timeout@entry=0xffff7d7f7308) at util/aio-posix.c:521 #6 0x00000000009b2b64 in run_poll_handlers (ctx=ctx@entry=0x6efea40, max_ns=max_ns@entry=4000, timeout=timeout@entry=0xffff7d7f7308) at util/aio-posix.c:559 #7 0x00000000009b2ca0 in try_poll_mode (ctx=ctx@entry=0x6efea40, timeout=0xffff7d7f7308, timeout@entry=0xffff7d7f7348) at util/aio-posix.c:594 #8 0x00000000009b31b8 in aio_poll (ctx=0x6efea40, blocking=blocking@entry=true) at util/aio-posix.c:636 #9 0x00000000006973cc in iothread_run (opaque=0x6ebd800) at iothread.c:75 #10 0x00000000009b592c in qemu_thread_start (args=0x6efef60) at util/qemu-thread-posix.c:502 #11 0x0000ffff8057f8bc in start_thread () from /lib64/libpthread.so.0 #12 0x0000ffff804e5f8c in thread_start () from /lib64/libc.so.6 (gdb) p bus $1 = (SCSIBus *) 0x0 Signed-off-by: Zhengui li <lizhengui@huawei.com> --- hw/scsi/virtio-scsi.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)