linux-kernel - Re: [PATCH 0/3] Enable legacy irq mode before jump to kexec/kdump kernel

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Date:	Wed, 20 Jul 2016 08:32:01 +0200 (CEST)
From:	Thomas Gleixner <tglx@...utronix.de>
To:	"bhe@...hat.com" <bhe@...hat.com>
cc:	"Wei, Jiangang" <weijg.fnst@...fujitsu.com>,
	"fenghua.yu@...el.com" <fenghua.yu@...el.com>,
	"x86@...nel.org" <x86@...nel.org>,
	"kexec@...ts.infradead.org" <kexec@...ts.infradead.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"mingo@...hat.com" <mingo@...hat.com>,
	"ebiederm@...ssion.com" <ebiederm@...ssion.com>,
	"hpa@...or.com" <hpa@...or.com>,
	"jiang.liu@...ux.intel.com" <jiang.liu@...ux.intel.com>,
	"vgoyal@...hat.com" <vgoyal@...hat.com>
Subject: Re: [PATCH 0/3] Enable legacy irq mode before jump to kexec/kdump
 kernel

On Wed, 20 Jul 2016, bhe@...hat.com wrote:
> On 07/20/16 at 03:54am, Wei, Jiangang wrote:
>
> >  In fact, Eric and Ingo suggested that "it should be fixed in the bootup
> > path of the dump kernel, not the crash kernel reboot path", which is
> > convincing and reasonable.
> 
> Well this patch doesn't do differently with Eric's original implemention
> in kexec/kdump path.
> By taking out clear_IO_APIC from disable_IO_APIC, the left code of
> disable_IO_APIC will only do the virtual wire setting. So for
> kexec/kdump path, code basically is the same as Eric's method. But for
> poweroff/halt/reboot, it's enough to call clear_IO_APIC to disable
> IO-APIC.

You're completely ignoring what Jiangang said: 

 "it should be fixed in the bootup path of the dump kernel, not the crash
  kernel reboot path"

and that's the right way to do it. End of story.

Thanks,

	tglx