From: Stefan Hajnoczi <[email protected]>
Commit e24a47c5b73e ("virtio-scsi: do not use vring in dataplane") set
dataplane_started to true when virtio_scsi_dataplane_start() fails. This
is likely a typo since dataplane is not functional after failure.
The non-ioeventfd fallback is broken because dataplane_started is true
after virtio_scsi_dataplane_start() failure. As a result, the following
assertion failure occurs when a virtio-scsi device exceeds the open file
descriptor ulimit when setting up notifiers (eventfds):
$ ulimit -n 104 # exact number can vary based on QEMU version
$ qemu-system-x86_64 -M q35,accel=kvm -m 1G -cpu host -smp 14 \
--blockdev
file,node-name=drive0,filename=test.img,cache.direct=on,aio=native \
--blockdev
file,node-name=drive1,filename=data01.img,cache.direct=on,aio=native \
--device virtio-scsi-pci,id=virtio-scsi-pci0 \
--device scsi-hd,drive=drive0,bus=virtio-scsi-pci0.0 \
--device virtio-scsi-pci,id=virtio-scsi-pci1 \
--device scsi-hd,drive=drive1,bus=virtio-scsi-pci1.0
qemu: virtio-scsi: Failed to set guest notifiers (-24), ensure -accel kvm is
set.
qemu: virtio_bus_start_ioeventfd: failed. Fallback to userspace (slower).
qemu-system-x86_64: ../hw/scsi/virtio-scsi.c:1017: virtio_scsi_reset:
Assertion `!s->dataplane_started' failed.
Aborted (core dumped)
Cc: Paolo Bonzini <[email protected]>
Fixes: e24a47c5b73e ("virtio-scsi: do not use vring in dataplane")
Buglink: https://redhat.atlassian.net/browse/RHEL-193328
Signed-off-by: Stefan Hajnoczi <[email protected]>
Reviewed-by: Philippe Mathieu-Daudé <[email protected]>
Reviewed-by: Michael S. Tsirkin <[email protected]>
Signed-off-by: Michael S. Tsirkin <[email protected]>
Message-ID: <[email protected]>
(cherry picked from commit 5440b6b5de469f62787f47f2b9177cb1136a85c1)
Signed-off-by: Michael Tokarev <[email protected]>
diff --git a/hw/scsi/virtio-scsi-dataplane.c b/hw/scsi/virtio-scsi-dataplane.c
index 95f13fb7c28..bcb6e441335 100644
--- a/hw/scsi/virtio-scsi-dataplane.c
+++ b/hw/scsi/virtio-scsi-dataplane.c
@@ -230,7 +230,7 @@ fail_host_notifiers:
fail_guest_notifiers:
s->dataplane_fenced = true;
s->dataplane_starting = false;
- s->dataplane_started = true;
+ s->dataplane_started = false;
return -ENOSYS;
}
--
2.47.3
