scsi: qla2xxx: do not queue commands when unloading
authorMauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Mon, 7 Nov 2016 19:53:30 +0000 (17:53 -0200)
committerMartin K. Petersen <martin.petersen@oracle.com>
Wed, 9 Nov 2016 00:13:07 +0000 (19:13 -0500)
commit04dfaa53a0b6e66b328a5bc549e3af8f8b6eac02
tree075eefbfa6adc5ebd722a052879b85f8fa1b5770
parent69e2d1e6c0af0dd7f18cfd434b008844568641a9
scsi: qla2xxx: do not queue commands when unloading

When the driver is unloading, in qla2x00_remove_one(), there is a single
call/point in time to abort ongoing commands, qla2x00_abort_all_cmds(),
which is still several steps away from the call to scsi_remove_host().

If more commands continue to arrive and be processed during that
interval, when the driver is tearing down and releasing its structures,
it might potentially hit an oops due to invalid memory access:

    Unable to handle kernel paging request for data at address 0x00000138
    <...>
    NIP [d000000004700a40] qla2xxx_queuecommand+0x80/0x3f0 [qla2xxx]
    LR [d000000004700a10] qla2xxx_queuecommand+0x50/0x3f0 [qla2xxx]

So, fail commands in qla2xxx_queuecommand() if the UNLOADING bit is set.

Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Acked-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
drivers/scsi/qla2xxx/qla_os.c