From 338b131a3269881c7431234855c93c219b0979b6 Mon Sep 17 00:00:00 2001 From: "sreekanth.reddy@lsi.com" Date: Tue, 17 Jul 2012 15:57:05 +0530 Subject: [SCSI] mpt2sas: Fix for Driver oops, when loading driver with max_queue_depth command line option to a very small value If the specified max_queue_depth setting is less than the expected number of internal commands, then driver will calculate the queue depth size to a negitive number. This negitive number is actually a very large number because variable is unsigned 16bit integer. So, the driver will ask for a very large amount of memory for message frames and resulting into oops as memory allocation routines will not able to handle such a large request. So, in order to limit this kind of oops, The driver need to set the max_queue_depth to a scsi mid layer's can_queue value. Then the overall message frames required for IO is minimum of either (max_queue_depth plus internal commands) or the IOC global credits. Signed-off-by: Sreekanth Reddy Cc: Signed-off-by: James Bottomley --- drivers/scsi/mpt2sas/mpt2sas_base.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) (limited to 'drivers/scsi/mpt2sas') diff --git a/drivers/scsi/mpt2sas/mpt2sas_base.c b/drivers/scsi/mpt2sas/mpt2sas_base.c index 9d46fcbe7755..b25757d1e91b 100644 --- a/drivers/scsi/mpt2sas/mpt2sas_base.c +++ b/drivers/scsi/mpt2sas/mpt2sas_base.c @@ -2424,10 +2424,13 @@ _base_allocate_memory_pools(struct MPT2SAS_ADAPTER *ioc, int sleep_flag) } /* command line tunables for max controller queue depth */ - if (max_queue_depth != -1) - max_request_credit = (max_queue_depth < facts->RequestCredit) - ? max_queue_depth : facts->RequestCredit; - else + if (max_queue_depth != -1 && max_queue_depth != 0) { + max_request_credit = min_t(u16, max_queue_depth + + ioc->hi_priority_depth + ioc->internal_depth, + facts->RequestCredit); + if (max_request_credit > MAX_HBA_QUEUE_DEPTH) + max_request_credit = MAX_HBA_QUEUE_DEPTH; + } else max_request_credit = min_t(u16, facts->RequestCredit, MAX_HBA_QUEUE_DEPTH); @@ -2502,7 +2505,7 @@ _base_allocate_memory_pools(struct MPT2SAS_ADAPTER *ioc, int sleep_flag) /* set the scsi host can_queue depth * with some internal commands that could be outstanding */ - ioc->shost->can_queue = ioc->scsiio_depth - (2); + ioc->shost->can_queue = ioc->scsiio_depth; dinitprintk(ioc, printk(MPT2SAS_INFO_FMT "scsi host: " "can_queue depth (%d)\n", ioc->name, ioc->shost->can_queue)); -- cgit v1.2.3