[PATCH v4 2/2] scsi: qla2xxx: check UNLOADING before posting async work

[mwilck@suse.com]

From: Martin Wilck <mwilck@suse.com>

qlt_free_session_done() tries to post async PRLO / LOGO, and
waits for the completion of these async commands. If UNLOADING
is set, this is doomed to timeout, because the async logout
command will never complete.

The only way to avoid waiting pointlessly is to fail posting
these commands in the first place if the driver is in UNLOADING state.
In general, posting any command should be avoided when the driver
is UNLOADING.

With this patch, "rmmod qla2xxx" completes without noticeable delay.

Fixes: 45235022da99 ("scsi: qla2xxx: Fix driver unload by shutting down chip")
Signed-off-by: Martin Wilck <mwilck@suse.com>
---
 drivers/scsi/qla2xxx/qla_os.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index ce0dabb..8cce3e2 100644
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -4862,6 +4862,9 @@ qla2x00_alloc_work(struct scsi_qla_host *vha, enum qla_work_type type)
 	struct qla_work_evt *e;
 	uint8_t bail;
 
+	if (test_bit(UNLOADING, &vha->dpc_flags))
+		return NULL;
+
 	QLA_VHA_MARK_BUSY(vha, bail);
 	if (bail)
 		return NULL;
-- 
2.26.0