path: root/drivers/s390/scsi
diff options
authorSteffen Maier <maier@linux.ibm.com>2019-10-01 12:49:49 +0200
committerMartin K. Petersen <martin.petersen@oracle.com>2019-10-03 21:45:53 -0400
commit2190168aaea42c31bff7b9a967e7b045f07df095 (patch)
tree967cabf75189175be824e5fd7f84989eba2612b5 /drivers/s390/scsi
parentscsi: core: save/restore command resid for error handling (diff)
scsi: zfcp: fix reaction on bit error threshold notification
On excessive bit errors for the FCP channel ingress fibre path, the channel notifies us. Previously, we only emitted a kernel message and a trace record. Since performance can become suboptimal with I/O timeouts due to bit errors, we now stop using an FCP device by default on channel notification so multipath on top can timely failover to other paths. A new module parameter zfcp.ber_stop can be used to get zfcp old behavior. User explanation of new kernel message: * Description: * The FCP channel reported that its bit error threshold has been exceeded. * These errors might result from a problem with the physical components * of the local fibre link into the FCP channel. * The problem might be damage or malfunction of the cable or * cable connection between the FCP channel and * the adjacent fabric switch port or the point-to-point peer. * Find details about the errors in the HBA trace for the FCP device. * The zfcp device driver closed down the FCP device * to limit the performance impact from possible I/O command timeouts. * User action: * Check for problems on the local fibre link, ensure that fibre optics are * clean and functional, and all cables are properly plugged. * After the repair action, you can manually recover the FCP device by * writing "0" into its "failed" sysfs attribute. * If recovery through sysfs is not possible, set the CHPID of the device * offline and back online on the service element. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: <stable@vger.kernel.org> #2.6.30+ Link: https://lore.kernel.org/r/20191001104949.42810-1-maier@linux.ibm.com Reviewed-by: Jens Remus <jremus@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Steffen Maier <maier@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/s390/scsi')
1 files changed, 13 insertions, 3 deletions
diff --git a/drivers/s390/scsi/zfcp_fsf.c b/drivers/s390/scsi/zfcp_fsf.c
index 296bbc3c4606..cf63916814cc 100644
--- a/drivers/s390/scsi/zfcp_fsf.c
+++ b/drivers/s390/scsi/zfcp_fsf.c
@@ -27,6 +27,11 @@
struct kmem_cache *zfcp_fsf_qtcb_cache;
+static bool ber_stop = true;
+module_param(ber_stop, bool, 0600);
+ "Shuts down FCP devices for FCP channels that report a bit-error count in excess of its threshold (default on)");
static void zfcp_fsf_request_timeout_handler(struct timer_list *t)
struct zfcp_fsf_req *fsf_req = from_timer(fsf_req, t, timer);
@@ -236,10 +241,15 @@ static void zfcp_fsf_status_read_handler(struct zfcp_fsf_req *req)
- dev_warn(&adapter->ccw_device->dev,
- "The error threshold for checksum statistics "
- "has been exceeded\n");
zfcp_dbf_hba_bit_err("fssrh_3", req);
+ if (ber_stop) {
+ dev_warn(&adapter->ccw_device->dev,
+ "All paths over this FCP device are disused because of excessive bit errors\n");
+ zfcp_erp_adapter_shutdown(adapter, 0, "fssrh_b");
+ } else {
+ dev_warn(&adapter->ccw_device->dev,
+ "The error threshold for checksum statistics has been exceeded\n");
+ }