public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
To: Borislav Petkov <bp@alien8.de>
Cc: jingbai.ma@hp.com, kexec@lists.infradead.org,
	linux-kernel@vger.kernel.org, ebiederm@xmission.com,
	akpm@linux-foundation.org, hpa@linux.intel.com,
	vgoyal@redhat.com
Subject: Re: [PATCH 2/2] x86, apic: Disable BSP if boot cpu is AP
Date: Mon, 09 Sep 2013 15:18:06 +0900	[thread overview]
Message-ID: <522D681E.1030809@jp.fujitsu.com> (raw)
In-Reply-To: <20130904061221.GA17791@x1.alien8.de>

(2013/09/04 15:12), Borislav Petkov wrote:
> On Mon, Sep 02, 2013 at 06:42:44PM +0900, HATAYAMA Daisuke wrote:
>> The reason why I don't lookup BSP flag in MSR is that it's impossible.
>> To read MSR of some CPU, we need to use rdmsr instruction on the CPU.
>> However, in case of this issue, the BSP is halting or running in
>> the kdump 1st kernel.
>
> Yes, and on the AP, that flag would be cleared which makes it not a BSP.
>
>> A whole explanation is written in the patch description.
>
> Those tend to get lost in git history when a bunch of whitespace jerk
> offs appear ontop. So a nicely written comment in the code could be very
> helpful.
>
> Thanks.
>

Yes, that's the point this patch series misses. I'll describe the explanation
in Documentation/kexec/kexec.txt and point it in the comment of boot-up code.

-- 
Thanks.
HATAYAMA, Daisuke


  reply	other threads:[~2013-09-09  6:21 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-08-29  9:27 [PATCH 0/2] x86, apic: Disable BSP if boot cpu is AP HATAYAMA Daisuke
2013-08-29  9:27 ` [PATCH 1/2] x86, apic: Add boot_cpu_is_bsp() to check if boot cpu is BSP HATAYAMA Daisuke
2013-10-09 23:15   ` [tip:x86/bsp-hotplug] " tip-bot for HATAYAMA Daisuke
2013-08-29  9:28 ` [PATCH 2/2] x86, apic: Disable BSP if boot cpu is AP HATAYAMA Daisuke
2013-08-31  5:22   ` Borislav Petkov
2013-09-02  2:32     ` HATAYAMA Daisuke
2013-09-02  7:13       ` Borislav Petkov
2013-09-02  9:42         ` HATAYAMA Daisuke
2013-09-04  6:12           ` Borislav Petkov
2013-09-09  6:18             ` HATAYAMA Daisuke [this message]
2013-10-09 23:16   ` [tip:x86/bsp-hotplug] " tip-bot for HATAYAMA Daisuke
2013-10-12 17:31     ` H. Peter Anvin
2013-10-12 17:42       ` Ingo Molnar
2013-11-11 19:54         ` H. Peter Anvin
2013-11-12 10:20           ` HATAYAMA Daisuke
2013-11-12 15:35             ` H. Peter Anvin
2013-08-29 13:54 ` [PATCH 0/2] " H. Peter Anvin
2013-08-29 23:37   ` Eric W. Biederman
2013-08-30 12:48     ` Vivek Goyal
2013-08-29 23:51   ` HATAYAMA Daisuke
2013-08-30 15:43     ` H. Peter Anvin
2013-10-09 20:20       ` Vivek Goyal
2013-10-14  9:03         ` Petr Tesarik

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=522D681E.1030809@jp.fujitsu.com \
    --to=d.hatayama@jp.fujitsu.com \
    --cc=akpm@linux-foundation.org \
    --cc=bp@alien8.de \
    --cc=ebiederm@xmission.com \
    --cc=hpa@linux.intel.com \
    --cc=jingbai.ma@hp.com \
    --cc=kexec@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=vgoyal@redhat.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox