linux-kernel - Re: [PATCH 17/41] mm/mmap: move VMA locking before anon_vma_lock

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: <Y8kN3stHeEyAoB+D@dhcp22.suse.cz>
Date:   Thu, 19 Jan 2023 10:31:10 +0100
From:   Michal Hocko <mhocko@...e.com>
To:     Suren Baghdasaryan <surenb@...gle.com>
Cc:     akpm@...ux-foundation.org, michel@...pinasse.org,
        jglisse@...gle.com, vbabka@...e.cz, hannes@...xchg.org,
        mgorman@...hsingularity.net, dave@...olabs.net,
        willy@...radead.org, liam.howlett@...cle.com, peterz@...radead.org,
        ldufour@...ux.ibm.com, laurent.dufour@...ibm.com,
        paulmck@...nel.org, luto@...nel.org, songliubraving@...com,
        peterx@...hat.com, david@...hat.com, dhowells@...hat.com,
        hughd@...gle.com, bigeasy@...utronix.de, kent.overstreet@...ux.dev,
        punit.agrawal@...edance.com, lstoakes@...il.com,
        peterjung1337@...il.com, rientjes@...gle.com,
        axelrasmussen@...gle.com, joelaf@...gle.com, minchan@...gle.com,
        jannh@...gle.com, shakeelb@...gle.com, tatashin@...gle.com,
        edumazet@...gle.com, gthelen@...gle.com, gurua@...gle.com,
        arjunroy@...gle.com, soheil@...gle.com, hughlynch@...gle.com,
        leewalsh@...gle.com, posk@...gle.com, linux-mm@...ck.org,
        linux-arm-kernel@...ts.infradead.org,
        linuxppc-dev@...ts.ozlabs.org, x86@...nel.org,
        linux-kernel@...r.kernel.org, kernel-team@...roid.com
Subject: Re: [PATCH 17/41] mm/mmap: move VMA locking before
 anon_vma_lock_write call

On Wed 18-01-23 13:48:13, Suren Baghdasaryan wrote:
> On Wed, Jan 18, 2023 at 1:33 PM Michal Hocko <mhocko@...e.com> wrote:
[...]
> > So it will become:
> > Move VMA flag modification (which now implies VMA locking) before
> > vma_adjust_trans_huge() to ensure the modifications are done after VMA
> > has been locked. Because vma_adjust_trans_huge() modifies the VMA and such
> > modifications should be done under VMA write-lock protection.
> >
> > which is effectivelly saying
> > vma_adjust_trans_huge() modifies the VMA and such modifications should
> > be done under VMA write-lock protection so move VMA flag modifications
> > before so all of them are covered by the same write protection.
> >
> > right?
> 
> Yes, and the wording in the latter version is simpler to understand
> IMO, so I would like to adopt it. Do you agree?

of course.
-- 
Michal Hocko
SUSE Labs