Re: [PATCH 2/2] zram: avoid NULL pointer access when reading mem_used_total

[Minchan Kim]

On Sat, Oct 25, 2014 at 05:26:31PM +0800, Weijie Yang wrote:
> There is a rare NULL pointer bug in mem_used_total_show() in concurrent
> situation, like this:
> zram is not initialized, process A is a mem_used_total reader which runs
> periodicity, while process B try to init zram.
> 
> 	process A 				process B
> access meta, get a NULL value
> 						init zram, done
> init_done() is true
> access meta->mem_pool, get a NULL pointer BUG
> 
> This patch fixes this issue.
> 	
> Signed-off-by: Weijie Yang <weijie.yang@xxxxxxxxxxx>
Acked-by: Minchan Kim <minchan@xxxxxxxxxx>

Thanks!

-- 
Kind regards,
Minchan Kim
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