This patch avoids a kernel warning that may occur if a virtio_scsi
controller is detached immediately following a disk detach. See the
commit message for details. The following are instructions to
produce the warning (without the proposed patch).
Timing matters--if all event work items call INIT_WORK before they are
flushed by cancel_work_sync, then the warning will not occur.
The warning will occur consistently if a sleep is added in
virtscsi_kick_event before the INIT_WORK call, like so:
#include <linux/delay.h>
static int virtscsi_kick_event(struct virtio_scsi *vscsi,
struct virtio_scsi_event_node *event_node)
{
int err;
struct scatterlist sg;
unsigned long flags;
-> msleep(1000);
INIT_WORK(&event_node->work, virtscsi_handle_event);
...
}
Then, just detach a disk and its controller in quick succession:
virsh detach-device --domain <domain> disk.xml; \
virsh detach-device --domain <domain> controller.xml
where disk.xml and controller.xml are text files containing the XML
of the disk and controller.
Or, with the libvirt python module:
domain.detachDevice(str(disk_xml))
domain.detachDevice(str(controller_xml))
Joshua Daley (1):
scsi: virtio_scsi: move INIT_WORK calls to virtscsi_init
drivers/scsi/virtio_scsi.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
--
2.34.1
