linux-kernel - Re: [PATCH 0/4] mmu_notifier semantic update

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] [day] [month] [year] [list]

Message-ID: <20170829201555.GG7546@redhat.com>
Date:   Tue, 29 Aug 2017 16:15:56 -0400
From:   Jerome Glisse <jglisse@...hat.com>
To:     linux-kernel@...r.kernel.org, linux-mm@...ck.org
Cc:     Linus Torvalds <torvalds@...ux-foundation.org>,
        Bernhard Held <berny156@....de>,
        Adam Borowski <kilobyte@...band.pl>,
        Andrea Arcangeli <aarcange@...hat.com>,
        Radim Krčmář <rkrcmar@...hat.com>,
        Wanpeng Li <kernellwp@...il.com>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Takashi Iwai <tiwai@...e.de>,
        Nadav Amit <nadav.amit@...il.com>,
        Mike Galbraith <efault@....de>,
        "Kirill A . Shutemov" <kirill.shutemov@...ux.intel.com>,
        axie <axie@....com>, Andrew Morton <akpm@...ux-foundation.org>,
        Dan Williams <dan.j.williams@...el.com>,
        Ross Zwisler <ross.zwisler@...ux.intel.com>
Subject: Re: [PATCH 0/4] mmu_notifier semantic update

On Tue, Aug 29, 2017 at 04:11:28PM -0400, Jérôme Glisse wrote:
> So we do not want to allow sleep during call to mmu_notifier_invalidate_page()
> but some code do not have surrounding mmu_notifier_invalidate_range_start()/
> mmu_notifier_invalidate_range_end() or mmu_notifier_invalidate_range()
> 
> This patch serie just make sure that there is at least a call (outside spinlock
> section) to mmu_notifier_invalidate_range() after mmu_notifier_invalidate_page()
> 
> This fix issue with AMD IOMMU v2 while avoiding to introduce issue for others
> user of the mmu_notifier API. For releavent threads see:
> 
> https://lkml.kernel.org/r/20170809204333.27485-1-jglisse@redhat.com
> https://lkml.kernel.org/r/20170804134928.l4klfcnqatni7vsc@black.fi.intel.com
> https://marc.info/?l=kvm&m=150327081325160&w=2

Please ignore this. Instead plan is to kill invalidate_page() switch
it to invalidate_range() and make sure there is always range_start/
range_end happening around.

Jérôme