Re: [Qemu-devel] [PATCH 1/4] X86: Intel MPX definiation

[H. Peter Anvin]

On 12/05/2013 08:08 AM, Paolo Bonzini wrote:
> Il 02/12/2013 17:43, Liu, Jinsong ha scritto:
>> From fbfa537f690eca139a96c6b2636ab5130bf57716 Mon Sep 17 00:00:00 2001
>> From: Liu Jinsong <address@hidden>
>> Date: Fri, 29 Nov 2013 01:27:00 +0800
>> Subject: [PATCH 1/4] X86: Intel MPX definiation
>>
>> Signed-off-by: Xudong Hao <address@hidden>
>> Signed-off-by: Liu Jinsong <address@hidden>
>> ---
>>  arch/x86/include/asm/cpufeature.h |    2 ++
>>  arch/x86/include/asm/xsave.h      |    5 ++++-
>>  2 files changed, 6 insertions(+), 1 deletions(-)
>>
> 
> hpa/Ingo/Thomas, can you give your Acked-by for this patch?
> 
> I'm not sure of the consequences of changing XCNTXT_MASK.  This series
> (which was submitted with the wrong threading) wants it so that KVM can
> use fpu_save_init and fpu_restore_checking to save and restore the MPX
> state of the guest.
> 

Hi, I'm currently reviewing internally another set of patches for MPX
support which would at least in part conflict with these.  I don't see
the rest of the series -- where was it posted?

Either way:

1. asm/cpufeatures.h patches should always be separate, as we put those
into a special branch into the -tip tree since they touch so many other
things.

2. Enabling MPX is only safe with XSTATE_EAGER, which Qiaowei's patchset
has done correctly.

        -hpa