v2.6.30 commit 63caf367e1c9 ("[SCSI] zfcp: Improve reliability of SCSI eh
handlers in zfcp") added calls to zfcp_erp_wait() within
eh_abort_handler(), eh_device_reset_handler(), eh_target_reset_handler()
in order to synchronize with zfcp recovery completion before returning
from a scsi_eh callback (e.g. with SUCCESS) to prevent eh escalation.
v2.6.33 commit af4de36d911a ("[SCSI] zfcp: Block scsi_eh thread for rport
state BLOCKED") introduced the use of fc_block_scsi_eh() for
eh_abort_handler(), eh_device_reset_handler(), eh_target_reset_handler(),
and eh_host_reset_handler(), because zfcp_erp_wait() from above commit is
not sufficient.
The use in zfcp_task_mgmt_function() is correct even for a LUN reset,
as described in commit 6f2ce1c6af37 ("scsi: zfcp: fix rport unblock race
with LUN recovery").
However, the one call in zfcp_scsi_eh_host_reset_handler() waiting for
just one arbitrary port of the arbitrary scsi_cmnd seems insufficient
as the preceding adapter recovery could have recovered multiple ports
for which we all should wait to unblock (or have run into FAST_IO_FAIL).
Therefore, we now wait for all ports of the adapter with this fix.
NB: We cannot easily wait for an event because there is a time window
between zfcp_erp_wait() returned and zfcp_erp_try_rport_unblock() as part
of zfcp_erp_action_cleanup() actually scheduled rport_work which will
unblock an rport in zfcp_scsi_rport_work() asynchronously. Hence a
flush_work() could come early before queue_work() was even done.
v2.6.35 commit a1dbfddd02d2 ("[SCSI] zfcp: Pass return code from
fc_block_scsi_eh to scsi eh") fixed v2.6.33 for the FAST_IO_FAIL case.
Signed-off-by: Steffen Maier <ma...@linux.vnet.ibm.com>
Fixes: af4de36d911a ("[SCSI] zfcp: Block scsi_eh thread for rport state
BLOCKED")
Fixes: a1dbfddd02d2 ("[SCSI] zfcp: Pass return code from fc_block_scsi_eh to
scsi eh")
---
drivers/s390/scsi/zfcp_scsi.c | 25 +++++++++++++++++++------
1 file changed, 19 insertions(+), 6 deletions(-)
diff --git a/drivers/s390/scsi/zfcp_scsi.c b/drivers/s390/scsi/zfcp_scsi.c
index 8e96196fa877..11cf33ea8c14 100644
--- a/drivers/s390/scsi/zfcp_scsi.c
+++ b/drivers/s390/scsi/zfcp_scsi.c
@@ -338,16 +338,29 @@ static int zfcp_scsi_eh_host_reset_handler(struct
scsi_cmnd *scpnt)
struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(scpnt->device);
struct zfcp_adapter *adapter = zfcp_sdev->port->adapter;
struct zfcp_port *port;
- int ret;
+ int ret = SUCCESS;
zfcp_erp_adapter_reopen(adapter, 0, "schrh_1");
zfcp_erp_wait(adapter);
- port = zfcp_sdev->port;
- ret = port->rport ? fc_block_rport(port->rport) : 0;
- if (ret)
- return ret;
+ /* after internal recovery, wait for async unblock of rport(s) */
+ read_lock(&adapter->port_list_lock);
+ list_for_each_entry(port, &adapter->port_list, list) {
+ int fc_ret;
+
+ if (!port->rport)
+ continue;
+
+ fc_ret = fc_block_rport(port->rport);
+ /* Any rport ran into fast_io_fail_tmo: FAST_IO_FAIL.
+ * To let pending requests bubble up, even if too many
+ * because of other rports without this timeout.
+ */
+ if (fc_ret)
+ ret = fc_ret;
+ }
+ read_unlock(&adapter->port_list_lock);
- return SUCCESS;
+ return ret;
}
struct scsi_transport_template *zfcp_scsi_transport_template;
--
2.11.2
