The hpsa firmware will bypass the cache for any request larger
than 1MB, so we should cap the request size to avoid any
performance degradation in SLE12-SP2.

This degradation is caused from d2be537c3ba3568acd79cd178327b842e60d035e,
which changed max_sectors_kb to 1280k, but the hardware is able to
work fine with it, so the true fix should be from hpsa driver.

References: bsc#1025461

Signed-off-by: Yadan Fan <yd...@suse.com>
---
 drivers/scsi/hpsa.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
index 73daace478cb..b4c0bbea680c 100644
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -952,7 +952,7 @@ static struct scsi_host_template hpsa_driver_template = {
 #endif
        .sdev_attrs = hpsa_sdev_attrs,
        .shost_attrs = hpsa_shost_attrs,
-       .max_sectors = 8192,
+       .max_sectors = 1024,
        .no_write_same = 1,
 };
 
-- 
2.12.3

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