3.16.60-rc1 review patch. If anyone has any objections, please let me know.
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From: Stefan Haberland sth@linux.vnet.ibm.com
commit 5d27a2bf6e14f5c7d1033ad1e993fcd0eba43e83 upstream.
When a new CKD storage volume is defined at the storage server, Linux may be relying on outdated information about that volume, which leads to the following errors:
1. Command Reject Errors for minidisk on z/VM:
dasd-eckd.b3193d: 0.0.XXXX: An error occurred in the DASD device driver, reason=09 dasd(eckd): I/O status report for device 0.0.XXXX: dasd(eckd): in req: 00000000XXXXXXXX CC:00 FC:04 AC:00 SC:17 DS:02 CS:00 RC:0 dasd(eckd): device 0.0.2046: Failing CCW: 00000000XXXXXXXX dasd(eckd): Sense(hex) 0- 7: 80 00 00 00 00 00 00 00 dasd(eckd): Sense(hex) 8-15: 00 00 00 00 00 00 00 00 dasd(eckd): Sense(hex) 16-23: 00 00 00 00 e1 00 0f 00 dasd(eckd): Sense(hex) 24-31: 00 00 40 e2 00 00 00 00 dasd(eckd): 24 Byte: 0 MSG 0, no MSGb to SYSOP
2. Equipment Check errors on LPAR or for dedicated devices on z/VM:
dasd(eckd): I/O status report for device 0.0.XXXX: dasd(eckd): in req: 00000000XXXXXXXX CC:00 FC:04 AC:00 SC:17 DS:0E CS:40 fcxs:01 schxs:00 RC:0 dasd(eckd): device 0.0.9713: Failing TCW: 00000000XXXXXXXX dasd(eckd): Sense(hex) 0- 7: 10 00 00 00 13 58 4d 0f dasd(eckd): Sense(hex) 8-15: 67 00 00 00 00 00 00 04 dasd(eckd): Sense(hex) 16-23: e5 18 05 33 97 01 0f 0f dasd(eckd): Sense(hex) 24-31: 00 00 40 e2 00 04 58 0d dasd(eckd): 24 Byte: 0 MSG f, no MSGb to SYSOP
Fix this problem by using the up-to-date information provided during online processing via the device specific SNEQ to detect the case of outdated LCU data. If there is a difference, perform a re-read of that data.
Reviewed-by: Jan Hoeppner hoeppner@linux.ibm.com Signed-off-by: Stefan Haberland sth@linux.vnet.ibm.com Signed-off-by: Martin Schwidefsky schwidefsky@de.ibm.com [bwh: Backported to 3.16: - Move up assignment of "private" - Adjust context] Signed-off-by: Ben Hutchings ben@decadent.org.uk --- --- a/drivers/s390/block/dasd_alias.c +++ b/drivers/s390/block/dasd_alias.c @@ -608,18 +608,26 @@ static int _schedule_lcu_update(struct a
int dasd_alias_add_device(struct dasd_device *device) { - struct dasd_eckd_private *private; - struct alias_lcu *lcu; + struct dasd_eckd_private *private = device->private; + __u8 uaddr = private->uid.real_unit_addr; + struct alias_lcu *lcu = private->lcu; unsigned long flags; int rc;
- private = (struct dasd_eckd_private *) device->private; - lcu = private->lcu; rc = 0;
/* need to take cdev lock before lcu lock */ spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags); spin_lock(&lcu->lock); + /* + * Check if device and lcu type differ. If so, the uac data may be + * outdated and needs to be updated. + */ + if (private->uid.type != lcu->uac->unit[uaddr].ua_type) { + lcu->flags |= UPDATE_PENDING; + DBF_DEV_EVENT(DBF_WARNING, device, "%s", + "uid type mismatch - trigger rescan"); + } if (!(lcu->flags & UPDATE_PENDING)) { rc = _add_device_to_lcu(lcu, device, device); if (rc)