[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[PATCH] hw/virtio: Add a protection against duplicate vu_scmi_stop calls
From: |
Milan Zamazal |
Subject: |
[PATCH] hw/virtio: Add a protection against duplicate vu_scmi_stop calls |
Date: |
Thu, 20 Jul 2023 12:10:37 +0200 |
The QEMU CI fails in virtio-scmi test occasionally. As reported by
Thomas Huth, this happens most likely when the system is loaded and it
fails with the following error:
qemu-system-aarch64: ../../devel/qemu/hw/pci/msix.c:659:
msix_unset_vector_notifiers: Assertion `dev->msix_vector_use_notifier &&
dev->msix_vector_release_notifier' failed.
../../devel/qemu/tests/qtest/libqtest.c:200: kill_qemu() detected QEMU death
from signal 6 (Aborted) (core dumped)
As discovered by Fabiano Rosas, the cause is a duplicate invocation of
msix_unset_vector_notifiers via duplicate vu_scmi_stop calls:
msix_unset_vector_notifiers
virtio_pci_set_guest_notifiers
vu_scmi_stop
vu_scmi_disconnect
...
qemu_chr_write_buffer
msix_unset_vector_notifiers
virtio_pci_set_guest_notifiers
vu_scmi_stop
vu_scmi_set_status
...
qemu_cleanup
While vu_scmi_stop calls are protected by vhost_dev_is_started()
check, it's apparently not enough. vhost-user-blk and vhost-user-gpio
use an extra protection, see f5b22d06fb (vhost: recheck dev state in
the vhost_migration_log routine) for the motivation. Let's use the
same in vhost-user-scmi, which fixes the failure above.
Fixes: a5dab090e142 ("hw/virtio: Add boilerplate for vhost-user-scmi device")
Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
---
hw/virtio/vhost-user-scmi.c | 7 +++++++
include/hw/virtio/vhost-user-scmi.h | 1 +
2 files changed, 8 insertions(+)
diff --git a/hw/virtio/vhost-user-scmi.c b/hw/virtio/vhost-user-scmi.c
index d386fb2df9..918bb7dcf7 100644
--- a/hw/virtio/vhost-user-scmi.c
+++ b/hw/virtio/vhost-user-scmi.c
@@ -63,6 +63,7 @@ static int vu_scmi_start(VirtIODevice *vdev)
error_report("Error starting vhost-user-scmi: %d", ret);
goto err_guest_notifiers;
}
+ scmi->started_vu = true;
/*
* guest_notifier_mask/pending not used yet, so just unmask
@@ -90,6 +91,12 @@ static void vu_scmi_stop(VirtIODevice *vdev)
struct vhost_dev *vhost_dev = &scmi->vhost_dev;
int ret;
+ /* vhost_dev_is_started() check in the callers is not fully reliable. */
+ if (!scmi->started_vu) {
+ return;
+ }
+ scmi->started_vu = false;
+
if (!k->set_guest_notifiers) {
return;
}
diff --git a/include/hw/virtio/vhost-user-scmi.h
b/include/hw/virtio/vhost-user-scmi.h
index 6175a74ebd..c90db77dd5 100644
--- a/include/hw/virtio/vhost-user-scmi.h
+++ b/include/hw/virtio/vhost-user-scmi.h
@@ -25,6 +25,7 @@ struct VHostUserSCMI {
VirtQueue *cmd_vq;
VirtQueue *event_vq;
bool connected;
+ bool started_vu;
};
#endif /* _QEMU_VHOST_USER_SCMI_H */
--
2.40.1
- [PATCH] hw/virtio: Add a protection against duplicate vu_scmi_stop calls,
Milan Zamazal <=