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Subject: Re: regulator: deadlock vs memory reclaim
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From:   Dmitry Osipenko <digetx@gmail.com>
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Date:   Mon, 10 Aug 2020 23:21:08 +0300
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10.08.2020 23:18, Michał Mirosław пишет:
> On Mon, Aug 10, 2020 at 11:15:28PM +0300, Dmitry Osipenko wrote:
>> 10.08.2020 23:09, Michał Mirosław пишет:
>>> At first I also thought so, but there's more. Below is a lockdep
>>> complaint with your patch applied. I did a similar patch and then two more
>>> (following) and that is still not enough (sysfs/debugfs do allocations,
>>> too).
>> Then it should be good to move the locking for init_coupling() like I
>> suggested and use GFP_NOWAIT for the two other cases. It all could be a
>> single small patch. Could you please check whether GFP_NOWAIT helps?
> 
> This would be equivalent to my patches. Problem with sysfs and debugfs
> remains as they don't have the option of GFP_NOWAIT. This needs to be
> moved outside of the locks.

Ah okay, you meant the debugfs core. I see now, thanks.