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

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Message-ID: <aQRy4rafpvo-W-j6@tiehlicka>
Date: Fri, 31 Oct 2025 09:27:14 +0100
From: Michal Hocko <mhocko@...e.com>
To: Ankit Agrawal <ankita@...dia.com>
Cc: 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 Wed 29-10-25 03:15:08, Ankit Agrawal wrote:
> >> +static void add_to_kill_pfn(struct task_struct *tsk,
> >> +                         struct vm_area_struct *vma,
> >> +                         struct list_head *to_kill,
> >> +                         unsigned long pfn)
> >> +{
> >> +     struct to_kill *tk;
> >> +
> >> +     tk = kmalloc(sizeof(*tk), GFP_ATOMIC);
> >> +     if (!tk)
> >> +             return;
> >
> > This is unfortunate.  GFP_ATOMIC is unreliable and we silently behave
> > as if it worked OK.
> 
> Got it. I'll mark this as a failure case.

why do you need to batch all processes and kill them at once? Can you
just kill one by one?
-- 
Michal Hocko
SUSE Labs