linux-kernel - Re: [PATCH 3/4] KVM: x86: introduce get_kvmclock

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]

Date:   Mon, 5 Sep 2016 15:59:27 +0200
From:   Paolo Bonzini <pbonzini@...hat.com>
To:     Roman Kagan <rkagan@...tuozzo.com>, linux-kernel@...r.kernel.org,
        kvm@...r.kernel.org, peterhornyack@...gle.com, rkrcmar@...hat.com,
        den@...nvz.org
Subject: Re: [PATCH 3/4] KVM: x86: introduce get_kvmclock_ns



On 02/09/2016 17:24, Roman Kagan wrote:
> On Thu, Sep 01, 2016 at 05:26:14PM +0200, Paolo Bonzini wrote:
>> Introduce a function that reads the exact nanoseconds value that is
>> provided to the guest in kvmclock.  This crystallizes the notion of
>> kvmclock as a thin veneer over a stable TSC, that the guest will
>> (hopefully) convert with NTP.  In other words, kvmclock is *not* a
>> paravirtualized host-to-guest NTP.
> 
> It might also be worth documenting this approach in a comment somewhere
> around pvclock_gtod_notify / update_pvclock_gtod or friends.  And, if
> those could be simplified due to this change, it would be great, too.

Yes, Radim or I are going to look at it next...

Paolo