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Date: Sat, 20 May 2017 00:09:43 -0400
From: "Theodore Ts'o" <tytso@mit.edu>
To: Tahsin Erdogan <tahsin@google.com>
Cc: Michal Hocko <mhocko@suse.com>, Jan Kara <jack@suse.com>,
        linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3] jbd2: preserve original nofs flag during journal
 restart
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References: <20170518093939.GD9084@quack2.suse.cz>
 <20170518162850.7618-1-tahsin@google.com>
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On Thu, May 18, 2017 at 09:28:50AM -0700, Tahsin Erdogan wrote:
> When a transaction starts, start_this_handle() saves current
> PF_MEMALLOC_NOFS value so that it can be restored at journal stop time.
> Journal restart is a special case that calls start_this_handle() without
> stopping the transaction. start_this_handle() isn't aware that the
> original value is already stored so it overwrites it with current value.
> 
> For instance, a call sequence like below leaves PF_MEMALLOC_NOFS flag set
> at the end:
> 
>   jbd2_journal_start()
>   jbd2__journal_restart()
>   jbd2_journal_stop()
> 
> Make jbd2__journal_restart() restore the original value before calling
> start_this_handle().
> 
> Fixes: 81378da64de6 ("jbd2: mark the transaction context with the scope GFP_NOFS context")
> Signed-off-by: Tahsin Erdogan <tahsin@google.com>
> Reviewed-by: Jan Kara <jack@suse.cz>

Thanks, applied.

						- Ted