linux-kernel - Re: move hyperv CHANNELMSG_UNLOAD from crashed kernel to kdump kernel

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: <87inql4g3v.fsf@vitty.brq.redhat.com>
Date:   Thu, 15 Dec 2016 11:54:44 +0100
From:   Vitaly Kuznetsov <vkuznets@...hat.com>
To:     Olaf Hering <olaf@...fle.de>
Cc:     kys@...rosoft.com, gregkh@...uxfoundation.org,
        linux-kernel@...r.kernel.org, devel@...uxdriverproject.org
Subject: Re: move hyperv CHANNELMSG_UNLOAD from crashed kernel to kdump kernel

Olaf Hering <olaf@...fle.de> writes:

> On Thu, Dec 15, Olaf Hering wrote:
>
>> On Thu, Dec 15, Vitaly Kuznetsov wrote:
>> 
>> > I see a number of minor but at least one major issue against such move:
>> > At least for some Hyper-V versions (2012R2 for example)
>> > CHANNELMSG_UNLOAD_RESPONSE is delivered to the CPU which initially sent 
>> > CHANNELMSG_REQUESTOFFERS and on kdump we may not have this CPU up as
>> > we usually do kdump with nr_cpus=1 (and on the CPU which crashed). 
>> 
>> Since the kdump or kexec kernel will send the unload during boot I would
>> expect the response to arrive where it was sent, independent from the
>> number of cpus.
>
> Wait, I just noticed that "REQUESTOFFERS" now. That might be a reason
> why my suggestion will not work.
>

Yep, that's what I meant to say.

-- 
  Vitaly