All of lore.kernel.org
 help / color / mirror / Atom feed
From: "H. Peter Anvin" <hpa@zytor.com>
To: "Ren, Qiaowei" <qiaowei.ren@intel.com>,
	"Liu, Jinsong" <jinsong.liu@intel.com>,
	Paolo Bonzini <pbonzini@redhat.com>
Cc: "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
	"x86@kernel.org" <x86@kernel.org>,
	Xudong Hao <xudong.hao@intel.com>,
	"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@kernel.org>
Subject: Re: [PATCH v2 3/3] X86, mpx: Intel MPX xstate feature definition
Date: Fri, 06 Dec 2013 17:07:12 -0800	[thread overview]
Message-ID: <52A274C0.4010509@zytor.com> (raw)
In-Reply-To: <9E0BE1322F2F2246BD820DA9FC397ADE014A6115@SHSMSX102.ccr.corp.intel.com>

On 12/06/2013 04:23 PM, Ren, Qiaowei wrote:
>>>
>>> We need to either disable these features in lazy mode, or we need to
>>> force eager mode if these features are to be supported.  The problem
>>> with the latter is that it means forcing eager mode regardless of if
>>> anything actually *uses* these features.
>>>
>>> A third option would be to require applications to use a prctl() or
>>> similar to enable eager-save features.
>>>
>>
>> The third option seems better -- how does native mpx patches work, force
>> eager?
>>
> It should be the second option, as you can see xsave.c which we remove from this patch. :)
> 

Ah yes... I missed the fact that that chunk had been dropped from this
patch.  It really shouldn't be.

I'll substitute the previous version of the patch.

	-hpa

WARNING: multiple messages have this Message-ID (diff)
From: "H. Peter Anvin" <hpa@zytor.com>
To: "Ren, Qiaowei" <qiaowei.ren@intel.com>,
	"Liu, Jinsong" <jinsong.liu@intel.com>,
	Paolo Bonzini <pbonzini@redhat.com>
Cc: "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
	"x86@kernel.org" <x86@kernel.org>,
	Xudong Hao <xudong.hao@intel.com>,
	"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Ingo Molnar <mingo@kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [Qemu-devel] [PATCH v2 3/3] X86,	mpx: Intel MPX xstate feature definition
Date: Fri, 06 Dec 2013 17:07:12 -0800	[thread overview]
Message-ID: <52A274C0.4010509@zytor.com> (raw)
In-Reply-To: <9E0BE1322F2F2246BD820DA9FC397ADE014A6115@SHSMSX102.ccr.corp.intel.com>

On 12/06/2013 04:23 PM, Ren, Qiaowei wrote:
>>>
>>> We need to either disable these features in lazy mode, or we need to
>>> force eager mode if these features are to be supported.  The problem
>>> with the latter is that it means forcing eager mode regardless of if
>>> anything actually *uses* these features.
>>>
>>> A third option would be to require applications to use a prctl() or
>>> similar to enable eager-save features.
>>>
>>
>> The third option seems better -- how does native mpx patches work, force
>> eager?
>>
> It should be the second option, as you can see xsave.c which we remove from this patch. :)
> 

Ah yes... I missed the fact that that chunk had been dropped from this
patch.  It really shouldn't be.

I'll substitute the previous version of the patch.

	-hpa


WARNING: multiple messages have this Message-ID (diff)
From: "H. Peter Anvin" <hpa@zytor.com>
To: "Ren, Qiaowei" <qiaowei.ren@intel.com>,
	"Liu, Jinsong" <jinsong.liu@intel.com>,
	Paolo Bonzini <pbonzini@redhat.com>
Cc: "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
	"x86@kernel.org" <x86@kernel.org>,
	Xudong Hao <xudong.hao@intel.com>,
	"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@kernel.org>
Subject: Re: [Qemu-devel] [PATCH v2 3/3] X86, mpx: Intel MPX xstate feature definition
Date: Fri, 06 Dec 2013 17:07:12 -0800	[thread overview]
Message-ID: <52A274C0.4010509@zytor.com> (raw)
In-Reply-To: <9E0BE1322F2F2246BD820DA9FC397ADE014A6115@SHSMSX102.ccr.corp.intel.com>

On 12/06/2013 04:23 PM, Ren, Qiaowei wrote:
>>>
>>> We need to either disable these features in lazy mode, or we need to
>>> force eager mode if these features are to be supported.  The problem
>>> with the latter is that it means forcing eager mode regardless of if
>>> anything actually *uses* these features.
>>>
>>> A third option would be to require applications to use a prctl() or
>>> similar to enable eager-save features.
>>>
>>
>> The third option seems better -- how does native mpx patches work, force
>> eager?
>>
> It should be the second option, as you can see xsave.c which we remove from this patch. :)
> 

Ah yes... I missed the fact that that chunk had been dropped from this
patch.  It really shouldn't be.

I'll substitute the previous version of the patch.

	-hpa

  reply	other threads:[~2013-12-07  1:07 UTC|newest]

Thread overview: 31+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-12-07  0:20 [PATCH v2 1/3] x86, mpx: add documentation on Intel MPX Qiaowei Ren
2013-12-07  0:20 ` [Qemu-devel] " Qiaowei Ren
2013-12-07  0:20 ` [PATCH v2 2/3] X86, mpx: Intel MPX CPU feature definition Qiaowei Ren
2013-12-07  0:20   ` [Qemu-devel] " Qiaowei Ren
2013-12-06 18:25   ` [tip:x86/cpufeature] x86, cpufeature: Define the Intel MPX feature flag tip-bot for Qiaowei Ren
2013-12-07  0:20 ` [PATCH v2 3/3] X86, mpx: Intel MPX xstate feature definition Qiaowei Ren
2013-12-07  0:20   ` [Qemu-devel] " Qiaowei Ren
2013-12-06 17:35   ` Paolo Bonzini
2013-12-06 17:35     ` [Qemu-devel] " Paolo Bonzini
2013-12-06 17:55     ` H. Peter Anvin
2013-12-06 17:55       ` [Qemu-devel] " H. Peter Anvin
2013-12-06 20:05     ` Liu, Jinsong
2013-12-06 20:05       ` [Qemu-devel] " Liu, Jinsong
2013-12-06 20:05       ` Liu, Jinsong
2013-12-06 21:33       ` H. Peter Anvin
2013-12-06 21:33         ` H. Peter Anvin
2013-12-06 22:12         ` Liu, Jinsong
2013-12-06 22:12           ` [Qemu-devel] " Liu, Jinsong
2013-12-06 22:12           ` Liu, Jinsong
2013-12-07  0:23           ` Ren, Qiaowei
2013-12-07  0:23             ` [Qemu-devel] " Ren, Qiaowei
2013-12-07  0:23             ` Ren, Qiaowei
2013-12-07  1:07             ` H. Peter Anvin [this message]
2013-12-07  1:07               ` H. Peter Anvin
2013-12-07  1:07               ` H. Peter Anvin
2013-12-07  1:16               ` Ren, Qiaowei
2013-12-07  1:16                 ` Ren, Qiaowei
2013-12-07  1:16                 ` Ren, Qiaowei
2013-12-07  1:19                 ` H. Peter Anvin
2013-12-07  1:19                   ` H. Peter Anvin
2013-12-07  1:21             ` [tip:x86/cpufeature] x86, xsave: Support eager-only xsave features, add MPX support tip-bot for Qiaowei Ren

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=52A274C0.4010509@zytor.com \
    --to=hpa@zytor.com \
    --cc=jinsong.liu@intel.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=pbonzini@redhat.com \
    --cc=qemu-devel@nongnu.org \
    --cc=qiaowei.ren@intel.com \
    --cc=tglx@linutronix.de \
    --cc=x86@kernel.org \
    --cc=xudong.hao@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.