Re: [PATCH] cfi: fix deadloop in cfi_cmdset_0002.c do_write_buffer

From: Boris Brezillon
Date: Sun Feb 03 2019 - 03:27:03 EST


+Przemyslaw

On Fri, 1 Feb 2019 07:30:39 +0800
Liu Jian <liujian56@xxxxxxxxxx> wrote:

> 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.

Looks like Przemyslaw reported and fixed the same problem.

>
> Fixes: dfeae1073583(mtd: cfi_cmdset_0002: Change write buffer to check
> correct value)

Can you put the Fixes tag on a single, and the format is

Fixes: <hash> ("message")

> Signed-off-by: Yi Huaijie <yihuaijie@xxxxxxxxxx>
> Signed-off-by: Liu Jian <liujian56@xxxxxxxxxx>

[1]http://patchwork.ozlabs.org/patch/1025566/

> ---
> 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);
> }