[PATCH 3.16.y-ckt 016/183] megaraid_sas: disable interrupt_mask before enabling hardware interrupts

[Luis Henriques]

3.16.7-ckt8 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: "Sumit.Saxena at avagotech.com" <Sumit.Saxena at avagotech.com>

commit c2ced1719a1b903350955a511e1666e6d05a7f5b upstream.

Update driver "mask_interrupts" before enable/disable hardware interrupt
in order to avoid missing interrupts because of "mask_interrupts" still
set to 1 and hardware interrupts are enabled.

Signed-off-by: Sumit Saxena <sumit.saxena at avagotech.com>
Signed-off-by: Chaitra Basappa <chaitra.basappa at avagotech.com>
Reviewed-by: Martin K. Petersen <martin.petersen at oracle.com>
Signed-off-by: Christoph Hellwig <hch at lst.de>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/scsi/megaraid/megaraid_sas_fusion.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/megaraid/megaraid_sas_fusion.c b/drivers/scsi/megaraid/megaraid_sas_fusion.c
index 22600419ae9f..9872ccb28f1f 100644
--- a/drivers/scsi/megaraid/megaraid_sas_fusion.c
+++ b/drivers/scsi/megaraid/megaraid_sas_fusion.c
@@ -100,6 +100,8 @@ megasas_enable_intr_fusion(struct megasas_instance *instance)
 {
 	struct megasas_register_set __iomem *regs;
 	regs = instance->reg_set;
+
+	instance->mask_interrupts = 0;
 	/* For Thunderbolt/Invader also clear intr on enable */
 	writel(~0, &regs->outbound_intr_status);
 	readl(&regs->outbound_intr_status);
@@ -108,7 +110,6 @@ megasas_enable_intr_fusion(struct megasas_instance *instance)
 
 	/* Dummy readl to force pci flush */
 	readl(&regs->outbound_intr_mask);
-	instance->mask_interrupts = 0;
 }
 
 /**