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authorsreekanth.reddy@lsi.com <sreekanth.reddy@lsi.com>2012-07-17 15:57:05 +0530
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-09-14 10:00:25 -0700
commit7a4601c0bfde4ed50c54f30c32c5677e3daec4f9 (patch)
tree54dcd326a9b53c50fc085940ee0837c8ae36046e
parent797efad403c63c9a94a8f78e06ccb3aa5b4980a9 (diff)
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SCSI: mpt2sas: Fix for Driver oops, when loading driver with max_queue_depth command line option to a very small value
commit 338b131a3269881c7431234855c93c219b0979b6 upstream. 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 <sreekanth.reddy@lsi.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/scsi/mpt2sas/mpt2sas_base.c13
1 files changed, 8 insertions, 5 deletions
diff --git a/drivers/scsi/mpt2sas/mpt2sas_base.c b/drivers/scsi/mpt2sas/mpt2sas_base.c
index 3f03342b303..c4cef569540 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_base.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_base.c
@@ -2417,10 +2417,13 @@ _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);
@@ -2495,7 +2498,7 @@ _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));