linux-kernel - Re: [PATCH 2/8] x86/head: Refactor 32-bit pgtable setup

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: <db52b9c5-d829-64f9-62ae-0ef589568225@oracle.com>
Date:   Fri, 2 Dec 2016 09:04:41 -0500
From:   Boris Ostrovsky <boris.ostrovsky@...cle.com>
To:     Ingo Molnar <mingo@...nel.org>
Cc:     Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>,
        "H. Peter Anvin" <hpa@...or.com>, david.vrabel@...rix.com,
        JGross@...e.com, roger.pau@...rix.com,
        linux-kernel@...r.kernel.org, xen-devel@...ts.xenproject.org,
        x86@...nel.org, Matt Fleming <matt@...eblueprint.co.uk>
Subject: Re: [PATCH 2/8] x86/head: Refactor 32-bit pgtable setup

On 12/02/2016 04:45 AM, Ingo Molnar wrote:
> * Boris Ostrovsky <boris.ostrovsky@...cle.com> wrote:
>
>> On 10/31/2016 08:33 AM, Boris Ostrovsky wrote:
>>>
>>> On 10/14/2016 02:05 PM, Boris Ostrovsky wrote:
>>>> From: Matt Fleming <matt@...eblueprint.co.uk>
>>>>
>>>> The new Xen PVH entry point requires page tables to be setup by the
>>>> kernel since it is entered with paging disabled.
>>>>
>>>> Pull the common code out of head_32.S and into pgtable_32.S so that
>>>> setup_pgtable_32 can be invoked from both the new Xen entry point and
>>>> the existing startup_32 code.
>>>
>>> Ping to x86 maintainers.
>> Pinging again.
>>
>> I will be re-sending this series at some point (it has been delayed by
>> some hypervisor changes that will be needed) but I'd like to hear from
>> x86 maintainers whether this will be acceptable before I post this again.
> Could this be done in C?

I suppose it could be, I haven't thought about it.

The goal here was to simply make existing startup code available to
others (Xen guest) without changes. Are you suggesting to build page
tables in C for the Xen guest only or to make startup_32 call new C code
as well?

-boris