2013-10-28 12:24:51

by Rashika Kheria

Subject: [PATCH v6 3/3] Staging: zram: Fix decrement of variable by calling bdput()

As suggested by Jerome Marchand "The code in reset_store get the block device
(bdget_disk()) but it does not put it (bdput()) when it's done using it.
The usage count is therefor incremented but never decremented."

Hence, this patch introduces a call to bdput() to decrement the variable after usage.

Signed-off-by: Rashika Kheria <[email protected]>
---
drivers/staging/zram/zram_drv.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/staging/zram/zram_drv.c b/drivers/staging/zram/zram_drv.c
index 9027975..98dac15 100644
--- a/drivers/staging/zram/zram_drv.c
+++ b/drivers/staging/zram/zram_drv.c
@@ -664,6 +664,7 @@ static ssize_t reset_store(struct device *dev,

/* Make sure all pending I/O is finished */
fsync_bdev(bdev);
+ bdput(bdev);

zram_reset_device(zram, true);
return len;
--
1.7.9.5

2013-10-29 00:47:19

by Minchan Kim

Subject: Re: [PATCH v6 3/3] Staging: zram: Fix decrement of variable by calling bdput()

On Mon, Oct 28, 2013 at 05:54:39PM +0530, Rashika Kheria wrote:
> As suggested by Jerome Marchand "The code in reset_store get the block device
> (bdget_disk()) but it does not put it (bdput()) when it's done using it.
> The usage count is therefor incremented but never decremented."
>
> Hence, this patch introduces a call to bdput() to decrement the variable after usage.
>
> Signed-off-by: Rashika Kheria <[email protected]>

I think this patch is for stable, too.
So, please read my previous reply.

And please relocate this with [2/3] and do bdput in all of error cases
in reset_store.

> ---
> drivers/staging/zram/zram_drv.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/staging/zram/zram_drv.c b/drivers/staging/zram/zram_drv.c
> index 9027975..98dac15 100644
> --- a/drivers/staging/zram/zram_drv.c
> +++ b/drivers/staging/zram/zram_drv.c
> @@ -664,6 +664,7 @@ static ssize_t reset_store(struct device *dev,
>
> /* Make sure all pending I/O is finished */
> fsync_bdev(bdev);
> + bdput(bdev);
>
> zram_reset_device(zram, true);
> return len;
> --
> 1.7.9.5
>
> --
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--
Kind regards,
Minchan Kim