linux-kernel - Re: [RFC 10/26] mm, slub: do initial checks in ___slab

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: <c0a21f92-54ed-4e2f-01c5-d669fbb188bb@suse.cz>
Date:   Tue, 8 Jun 2021 14:13:20 +0200
From:   Vlastimil Babka <vbabka@...e.cz>
To:     Mel Gorman <mgorman@...hsingularity.net>
Cc:     linux-mm@...ck.org, linux-kernel@...r.kernel.org,
        Christoph Lameter <cl@...ux.com>,
        David Rientjes <rientjes@...gle.com>,
        Pekka Enberg <penberg@...nel.org>,
        Joonsoo Kim <iamjoonsoo.kim@....com>,
        Sebastian Andrzej Siewior <bigeasy@...utronix.de>,
        Thomas Gleixner <tglx@...utronix.de>,
        Jesper Dangaard Brouer <brouer@...hat.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Jann Horn <jannh@...gle.com>
Subject: Re: [RFC 10/26] mm, slub: do initial checks in ___slab_alloc() with
 irqs enabled

On 5/25/21 3:04 PM, Mel Gorman wrote:
> On Tue, May 25, 2021 at 01:39:30AM +0200, Vlastimil Babka wrote:
>> As another step of shortening irq disabled sections in ___slab_alloc(), don't
>> disable irqs until doing initial checks if there is a cached percpu slab and
>> it's suitable for our allocation.
>> 
>> Now we have to recheck c->page after actually disabling irqs as an allocation
>> in irq might have replaced it.
>> 
>> Signed-off-by: Vlastimil Babka <vbabka@...e.cz>
> 
> Minor nit only -- consider adding a comment at the new_slab label that
> IRQs must be disabled already.

Good point, will use lockdep_assert_irqs_disabled() as that's a functional comment.

> Acked-by: Mel Gorman <mgorman@...hsingularity.net>

Thanks.