linux-kernel - Re: [PATCH 4/8] hugetlb: handle truncate racing with page faults

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: <yt9d5yhzk30d.fsf@linux.ibm.com>
Date:   Wed, 07 Sep 2022 10:22:26 +0200
From:   Sven Schnelle <svens@...ux.ibm.com>
To:     Mike Kravetz <mike.kravetz@...cle.com>
Cc:     Miaohe Lin <linmiaohe@...wei.com>, linux-mm@...ck.org,
        linux-kernel@...r.kernel.org,
        Muchun Song <songmuchun@...edance.com>,
        David Hildenbrand <david@...hat.com>,
        Michal Hocko <mhocko@...e.com>, Peter Xu <peterx@...hat.com>,
        Naoya Horiguchi <naoya.horiguchi@...ux.dev>,
        "Aneesh Kumar K . V" <aneesh.kumar@...ux.vnet.ibm.com>,
        Andrea Arcangeli <aarcange@...hat.com>,
        "Kirill A . Shutemov" <kirill.shutemov@...ux.intel.com>,
        Davidlohr Bueso <dave@...olabs.net>,
        Prakash Sangappa <prakash.sangappa@...cle.com>,
        James Houghton <jthoughton@...gle.com>,
        Mina Almasry <almasrymina@...gle.com>,
        Pasha Tatashin <pasha.tatashin@...een.com>,
        Axel Rasmussen <axelrasmussen@...gle.com>,
        Ray Fucillo <Ray.Fucillo@...ersystems.com>,
        linux-s390@...r.kernel.org, hca@...ux.ibm.com, gor@...ux.ibm.com,
        Alexander Gordeev <agordeev@...ux.ibm.com>,
        Andrew Morton <akpm@...ux-foundation.org>
Subject: Re: [PATCH 4/8] hugetlb: handle truncate racing with page faults

Mike Kravetz <mike.kravetz@...cle.com> writes:

> Would you be willing to try the patch below in your environment?
> It addresses the stall I can create with a file that has a VERY large hole.
> In addition, it passes libhugetlbfs tests and has run for a while in my
> truncate/page fault race stress test.  However, it is very early code.
> It would be nice to see if it addresses the issue in your environment.

Yes, that fixes the issue for me. I added some debugging yesterday
evening after sending the initial report, and the end value in the loop
was indeed quite large - i didn't record the exact number, but it was
something like 0xffffffffff800001. Feel free to add my Tested-by.

Thanks
Sven