From: Tom Yan <tom.ty89@gmail.com>
Date: Fri, 22 Jul 2016 18:34:08 +0000 (+0800)
Subject: libata-scsi: use u8 array to store mode page copy
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=d7372cb6290eedadcf2d191b033388df3c0c39f2;p=deliverable%2Flinux.git

libata-scsi: use u8 array to store mode page copy

ata_mselect_*() would initialize a char array for storing a copy of
the current mode page. However, char could be signed char. In that
case, bytes larger than 127 would be converted to negative number.

For example, 0xff from def_control_mpage[] would become -1. This
prevented ata_mselect_control() from working at all, since when it
did the read-only bits check, there would always be a mismatch.

Signed-off-by: Tom Yan <tom.ty89@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
---

diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index e207b33e4ce9..0bc4532bb60a 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -3610,7 +3610,7 @@ static int ata_mselect_caching(struct ata_queued_cmd *qc,
 {
 	struct ata_taskfile *tf = &qc->tf;
 	struct ata_device *dev = qc->dev;
-	char mpage[CACHE_MPAGE_LEN];
+	u8 mpage[CACHE_MPAGE_LEN];
 	u8 wce;
 	int i;
 
@@ -3666,7 +3666,7 @@ static int ata_mselect_control(struct ata_queued_cmd *qc,
 			       const u8 *buf, int len, u16 *fp)
 {
 	struct ata_device *dev = qc->dev;
-	char mpage[CONTROL_MPAGE_LEN];
+	u8 mpage[CONTROL_MPAGE_LEN];
 	u8 d_sense;
 	int i;