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Date: Tue, 9 Jun 2026 18:30:00 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Ruoyu Wang <ruoyuw560@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>, Johannes Weiner <hannes@cmpxchg.org>,
 Roman Gushchin <roman.gushchin@linux.dev>, Shakeel Butt
 <shakeel.butt@linux.dev>, Muchun Song <muchun.song@linux.dev>,
 cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm: memcontrol-v1: use nofail allocations for soft
 limit trees
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On Mon, 8 Jun 2026 16:34:48 +0800 Ruoyu Wang <ruoyuw560@gmail.com> wrote:

> This was found by static analysis and then checked by reading the code:
> memcg1_init() dereferences rtpn unconditionally after kzalloc_node(). I
> treated the soft-limit tree as mandatory memcg v1 init state and used
> __GFP_NOFAIL because continuing without it would not be useful.
> 
> I agree this is early boot init code, and I do not have a
> runtime failure report or fault-injection reproduction for it.

Thanks.

Please teach the static analyzer that kernel practice is to ignore
allocation failures in __init code.