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From:   Liu Jian <liujian56@huawei.com>
To:     <dwmw2@infradead.org>, <computersforpeace@gmail.com>,
        <bbrezillon@kernel.org>, <marek.vasut@gmail.com>, <richard@nod.at>,
        <joakim.tjernlund@infinera.com>, <ikegami@allied-telesis.co.jp>,
        <keescook@chromium.org>
CC:     <liujian56@huawei.com>, <linux-mtd@lists.infradead.org>,
        <linux-kernel@vger.kernel.org>
Subject: [PATCH v2] cfi: fix deadloop in cfi_cmdset_0002.c do_write_buffer
Date:   Wed, 20 Feb 2019 04:47:14 +0800
Message-ID: <1550609234-40861-1-git-send-email-liujian56@huawei.com>
MIME-Version: 1.0
Content-Type: text/plain
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

In function do_write_buffer(), in the for loop, there is a case
chip_ready() returns 1 while chip_good() returns 0, so it never
break the loop.
To fix this, chip_good() is enough and it should timeout if it stay
bad for a while.

Fixes: dfeae1073583 ("mtd: cfi_cmdset_0002: Change write buffer to check correct value")
Signed-off-by: Yi Huaijie <yihuaijie@huawei.com>
Signed-off-by: Liu Jian <liujian56@huawei.com>
Reviewed-by: Tokunori Ikegami <ikegami_to@yahoo.co.jp>
---
v1->v2:
change git log, put the Fixes tag on a single line

 drivers/mtd/chips/cfi_cmdset_0002.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c
index 72428b6..818e94b 100644
--- a/drivers/mtd/chips/cfi_cmdset_0002.c
+++ b/drivers/mtd/chips/cfi_cmdset_0002.c
@@ -1876,14 +1876,14 @@ static int __xipram do_write_buffer(struct map_info *map, struct flchip *chip,
 			continue;
 		}
 
-		if (time_after(jiffies, timeo) && !chip_ready(map, adr))
-			break;
-
 		if (chip_good(map, adr, datum)) {
 			xip_enable(map, chip, adr);
 			goto op_done;
 		}
 
+		if (time_after(jiffies, timeo))
+			break;
+
 		/* Latency issues. Drop the lock, wait a while and retry */
 		UDELAY(map, chip, adr, 1);
 	}
-- 
2.7.4