linux-kernel - Re: [RFC PATCH 2/2] mm/vmscan.c: Prevent allocating shrinker

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: <d9d14beb-ee20-7ebb-e007-fbf58fb28535@redhat.com>
Date:   Mon, 6 Dec 2021 11:45:54 +0100
From:   David Hildenbrand <david@...hat.com>
To:     Michal Hocko <mhocko@...e.com>, Nico Pache <npache@...hat.com>
Cc:     linux-kernel@...r.kernel.org, linux-mm@...ck.org,
        akpm@...ux-foundation.org, shakeelb@...gle.com,
        ktkhai@...tuozzo.com, shy828301@...il.com, guro@...com,
        vbabka@...e.cz, vdavydov.dev@...il.com, raquini@...hat.com
Subject: Re: [RFC PATCH 2/2] mm/vmscan.c: Prevent allocating shrinker_info on
 offlined nodes

> This doesn't seen complete. Slab shrinkers are used in the reclaim
> context. Previously offline nodes could be onlined later and this would
> lead to NULL ptr because there is no hook to allocate new shrinker
> infos. This would be also really impractical because this would have to
> update all existing memcgs...

Instead of going through the trouble of updating...

...  maybe just keep for_each_node() and check if the target node is
offline. If it's offline, just allocate from the first online node.
After all, we're not using __GFP_THISNODE, so there are no guarantees
either way ...

-- 
Thanks,

David / dhildenb