linux-ext4 - Re: [PATCH 1/5] ext4: fix race with setting free_inode/clusters

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Date:   Sun, 29 Jul 2018 21:30:09 -0400
From:   "Theodore Y. Ts'o" <tytso@....edu>
To:     Wang Shilong <wangshilong1991@...il.com>
Cc:     linux-ext4@...r.kernel.org, andreas.dilger@...el.com,
        sihara@....com, wshilong@....com
Subject: Re: [PATCH 1/5] ext4: fix race with setting
 free_inode/clusters_counter

On Tue, May 29, 2018 at 08:45:13PM +0900, Wang Shilong wrote:
> From: Wang Shilong <wshilong@....com>
> 
> Whenever we hit block or inode bitmap corruptions we set
> bit and then reduce this block group free inode/clusters
> counter to expose right available space.
> 
> However some of ext4_mark_group_bitmap_corrupted() is called
> inside group spinlock, some are not, this could make it happen
> that we double reduce one block group free counters from system.
> 
> Always hold group spinlock for it could fix it, but it looks
> a little heavy, we could use test_and_set_bit() to fix race
> problems here.
> 
> Signed-off-by: Wang Shilong <wshilong@....com>

Applied, thanks.

						- Ted