linux-kernel - Re: [PATCH 2/5] memcg: nmi safe memcg stats for specific archs

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <e859d24a-4619-4214-a3c5-b547b430e525@suse.cz>
Date: Fri, 16 May 2025 11:43:04 +0200
From: Vlastimil Babka <vbabka@...e.cz>
To: Shakeel Butt <shakeel.butt@...ux.dev>,
 Andrew Morton <akpm@...ux-foundation.org>
Cc: Johannes Weiner <hannes@...xchg.org>, Michal Hocko <mhocko@...nel.org>,
 Roman Gushchin <roman.gushchin@...ux.dev>,
 Muchun Song <muchun.song@...ux.dev>, Alexei Starovoitov <ast@...nel.org>,
 Sebastian Andrzej Siewior <bigeasy@...utronix.de>,
 Harry Yoo <harry.yoo@...cle.com>, Yosry Ahmed <yosry.ahmed@...ux.dev>,
 Peter Zijlstra <peterz@...radead.org>,
 Mathieu Desnoyers <mathieu.desnoyers@...icios.com>, bpf@...r.kernel.org,
 linux-mm@...ck.org, cgroups@...r.kernel.org, linux-kernel@...r.kernel.org,
 Meta kernel team <kernel-team@...a.com>
Subject: Re: [PATCH 2/5] memcg: nmi safe memcg stats for specific archs

On 5/16/25 08:49, Shakeel Butt wrote:
> There are archs which have NMI but does not support this_cpu_* ops
> safely in the nmi context but they support safe atomic ops in nmi
> context. For such archs, let's add infra to use atomic ops for the memcg
> stats which can be updated in nmi.
> 
> At the moment, the memcg stats which get updated in the objcg charging
> path are MEMCG_KMEM, NR_SLAB_RECLAIMABLE_B & NR_SLAB_UNRECLAIMABLE_B.
> Rather than adding support for all memcg stats to be nmi safe, let's
> just add infra to make these three stats nmi safe which this patch is
> doing.
> 
> Signed-off-by: Shakeel Butt <shakeel.butt@...ux.dev>

Acked-by: Vlastimil Babka <vbabka@...e.cz>