linux/drivers/scsi/mpt3sas
Mauricio Faria de Oliveira 9ff549ffb4 scsi: mpt3sas: fix oops in error handlers after shutdown/unload
This patch adds checks for 'ioc->remove_host' in the SCSI error handlers, so
not to access pointers/resources potentially freed in the PCI shutdown/module
unload path.  The error handlers may be invoked after shutdown/unload,
depending on other components.

This problem was observed with kexec on a system with a mpt3sas based adapter
and an infiniband adapter which takes long enough to shutdown:

The mpt3sas driver finished shutting down / disabled interrupt handling, thus
some commands have not finished and timed out.

Since the system was still running (waiting for the infiniband adapter to
shutdown), the scsi error handler for task abort of mpt3sas was invoked, and
hit an oops -- either in scsih_abort() because 'ioc->scsi_lookup' was NULL
without commit dbec4c9040 ("scsi: mpt3sas: lockless command submission"), or
later up in scsih_host_reset() (with or without that commit), because it
eventually called mpt3sas_base_get_iocstate().

After the above commit, the oops in scsih_abort() does not occur anymore
(_scsih_scsi_lookup_find_by_scmd() is no longer called), but that commit is
too big and out of the scope of linux-stable, where this patch might help, so
still go for the changes.

Also, this might help to prevent similar errors in the future, in case code
changes and possibly tries to access freed stuff.

Note the fix in scsih_host_reset() is still important anyway.

Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Acked-by: Sreekanth Reddy <Sreekanth.Reddy@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-02-21 22:45:45 -05:00
..
mpi SCSI misc on 20171114 2017-11-14 16:23:44 -08:00
Kconfig mpt3sas: fix Kconfig dependency problem for mpt2sas back compatibility 2015-12-03 09:31:23 -08:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mpt3sas_base.c scsi: mpt3sas: fix an out of bound write 2018-01-30 21:10:44 -05:00
mpt3sas_base.h scsi: mpt3sas: lockless command submission 2018-01-10 23:25:04 -05:00
mpt3sas_config.c scsi: mpt3sas: API 's to support NVMe drive addition to SML 2017-11-03 12:20:52 -04:00
mpt3sas_ctl.c scsi: mpt3sas: lockless command submission 2018-01-10 23:25:04 -05:00
mpt3sas_ctl.h scripts/spelling.txt: add "overwritting" pattern and fix typo instances 2017-02-27 18:43:47 -08:00
mpt3sas_debug.h mpt2sas, mpt3sas: Remove SCSI_MPTXSAS_LOGGING entry from Kconfig 2015-11-11 18:31:14 -05:00
mpt3sas_scsih.c scsi: mpt3sas: fix oops in error handlers after shutdown/unload 2018-02-21 22:45:45 -05:00
mpt3sas_transport.c scsi: scsi_transport_sas: switch to bsg-lib for SMP passthrough 2017-08-29 21:51:45 -04:00
mpt3sas_trigger_diag.c mpt2sas, mpt3sas: Update attribution language to Avago 2015-01-13 16:27:27 +01:00
mpt3sas_trigger_diag.h mpt2sas, mpt3sas: Update attribution language to Avago 2015-01-13 16:27:27 +01:00
mpt3sas_warpdrive.c scsi: mpt3sas: lockless command submission 2018-01-10 23:25:04 -05:00