linux-kernel - Re: [PATCH] memcg: Remove the lockdep assert from __mod_objcg

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: <c84d6962-34fa-42e5-899c-925579cbfb26@kernel.org>
Date: Tue, 28 May 2024 15:44:51 +0200
From: "Vlastimil Babka (SUSE)" <vbabka@...nel.org>
To: Sebastian Andrzej Siewior <bigeasy@...utronix.de>
Cc: Shakeel Butt <shakeel.butt@...ux.dev>,
 Andrew Morton <akpm@...ux-foundation.org>,
 Johannes Weiner <hannes@...xchg.org>, Michal Hocko <mhocko@...nel.org>,
 Roman Gushchin <roman.gushchin@...ux.dev>,
 Muchun Song <muchun.song@...ux.dev>, linux-mm@...ck.org,
 linux-kernel@...r.kernel.org, Thomas Gleixner <tglx@...utronix.de>
Subject: Re: [PATCH] memcg: Remove the lockdep assert from
 __mod_objcg_mlstate().

On 5/28/24 3:40 PM, Sebastian Andrzej Siewior wrote:
> On 2024-05-28 14:34:55 [+0200], Vlastimil Babka (SUSE) wrote:
>> > The safety of the counter update is already ensured by
>> > VM_WARN_ON_IRQS_ENABLED() which is part of memcg_stats_lock() and does
>> > not require yet another check.
>> 
>> I think here it's __mod_memcg_lruvec_state() doing the VM_WARN_ON_ as we
>> don't go through memcg_stats_lock()?
> 
> It is either VM_WARN_ON_IRQS_ENABLED() directly as in
> __mod_memcg_lruvec_state() (which is special) or memcg_stats_lock().
> 
> Do you want me to rephrase this part?

I think just s/memcg_stats_lock()/__mod_memcg_lruvec_state()/ in your
phrasing, since we are removing the lockdep assert from path that calls
__mod_memcg_lruvec_state() and not memcg_stats_lock()?
Or am I missing something?

> Sebastian