[SRU][B][F][PATCH 0/1] zfcp: Fix panic on ERP timeout for previously dismissed ERP (LP: 1887774)

[frank.heimes at canonical.com]

Buglink: https://bugs.launchpad.net/bugs/1887774

SRU Justification:

[Impact]

* Linux kernel panics due to kernel page fault in IRQ context when running zfcp_erp_timeout_handler() calling zfcp_erp_notify().

[Fix]

* 936e6b85da0476dd2edac7c51c68072da9fb4ba2 936e6b85da04 "scsi: zfcp: Fix panic on ERP timeout for previously dismissed ERP action"

[Test Case]

* Requires an IBM z13/z13s or LinuxONE Rockhopper/Emperor system (or newer) connected to zfcp capcble storage sub-system.

* Initiate an (ERP) timeout (maybe by injection or by causing a slow recovery otherwise).

* Monitor the system log for any kernel panics.

[Regression Potential]

* The regression can be considered as medium since the modification is platform specific / limited to s390x and again limited to the zfcp layer.

* Within zfcp it's further limited to the error recovery procedure (ERP) of fcp and only touches zfcp_erp.c, means the code path is mainly active under error conditions.

[Other]

* The above fix is upstream accepted with v5.8-rc3, hence will make it's way to groovy with kernel 5.8.

* Therefore this SRU request was submitted for bionic and focal only and not for groovy.

Steffen Maier (1):
  From: Author: Steffen Maier <maier at linux.ibm.com>

 drivers/s390/scsi/zfcp_erp.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

-- 
2.25.1