[SCSI] mpt2sas: Fix unsafe using smp_processor_id() in preemptible

nagalakshmi.nandigama@lsi.com · James Bottomley · commit a2c658505bf5 · 2012-06-06T12:38:56.000+09:00
When CONFIG_DEBUG_PREEMPT is enabled, bug is observed in the smp_processor_id().
This is because smp_processor_id() is not called in preempt safe condition.

To fix this issue, use raw_smp_processor_id instead of smp_processor_id.

Signed-off-by: Nagalakshmi Nandigama &lt;nagalakshmi.nandigama@lsi.com&gt;
CC: stable@vger.kernel.org
Signed-off-by: James Bottomley &lt;JBottomley@Parallels.com&gt;
diff --git a/drivers/scsi/mpt2sas/mpt2sas_base.c b/drivers/scsi/mpt2sas/mpt2sas_base.c
@@ -1792,7 +1792,7 @@ static inline void _base_writeq(__u64 b, volatile void __iomem *addr,
 static inline u8
 _base_get_msix_index(struct MPT2SAS_ADAPTER *ioc)
 {
-	return ioc->cpu_msix_table[smp_processor_id()];
+	return ioc->cpu_msix_table[raw_smp_processor_id()];
 }
 
 /**

Original file line number	Diff line number	Diff line change
`@@ -1792,7 +1792,7 @@ static inline void _base_writeq(__u64 b, volatile void __iomem *addr,`
`1792`	`1792`	`static inline u8`
`1793`	`1793`	`_base_get_msix_index(struct MPT2SAS_ADAPTER *ioc)`
`1794`	`1794`	`{`
`1795`		`- return ioc->cpu_msix_table[smp_processor_id()];`
	`1795`	`+ return ioc->cpu_msix_table[raw_smp_processor_id()];`
`1796`	`1796`	`}`
`1797`	`1797`
`1798`	`1798`	`/**`