linux-kernel - Re: [PATCH v4 2/3] mm: handle poisoning of pfn without struct pages

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Message-ID: <aQnXYsPR7zkV_ram@tiehlicka>
Date: Tue, 4 Nov 2025 11:37:22 +0100
From: Michal Hocko <mhocko@...e.com>
To: Andrew Morton <akpm@...ux-foundation.org>
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Subject: Re: [PATCH v4 2/3] mm: handle poisoning of pfn without struct pages

On Mon 03-11-25 18:52:26, Andrew Morton wrote:
> On Mon, 3 Nov 2025 19:22:09 +0100 Michal Hocko <mhocko@...e.com> wrote:
> 
> > > Hi Michal, I am trying to replicate what is being done today for non-PFNMAP
> > > memory failure in __add_to_kill
> > > (https://github.com/torvalds/linux/blob/master/mm/memory-failure.c#L376).
> > > For this series, I am inclined to keep it uniform.
> > 
> > Unless there is a very good reason for this code then I would rather not
> > rely on an atomic allocation. This just makes the behavior hard to
> > predict
> 
> I don't think this was addressed in the v5 series.
> 
> Yes please, anything we can do to avoid GFP_ATOMIC makes the kernel
> more reliable.

This could be done on top of the series because as such this is not a
blocker but it would be really great if we can stop copying a bad code
and rather get rid of it also in other poisoning code.

-- 
Michal Hocko
SUSE Labs