From e2c7b433f729cedb32514480af8cbdf2fe5cf264 Mon Sep 17 00:00:00 2001 From: Yadan Fan Date: Fri, 23 Jun 2017 17:40:05 +0800 Subject: [PATCH] scsi: hpsa: limit transfer length to 1MB 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 kernels later than v4.3 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. Signed-off-by: Yadan Fan Reviewed-by: Johannes Thumshirn Acked-by: Don Brace Signed-off-by: Martin K. Petersen --- 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 8914eab84337..4f7cdb28bd38 100644 --- a/drivers/scsi/hpsa.c +++ b/drivers/scsi/hpsa.c @@ -938,7 +938,7 @@ 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, };