From 195d1525797cd1630eb0faa48ba55a5fb024ca44 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 7710967a4bafa086e856613ff26cd941c7c29cbb, 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 8914eab843372..4f7cdb28bd38f 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, }; -- 2.39.5