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Subject: Re: [PATCH v5 10/12] x86/xen: Bypass intr mode setup in enlighten_pv
 system
To: Thomas Gleixner <tglx@linutronix.de>
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From: Dou Liyang <douly.fnst@cn.fujitsu.com>
Message-ID: <d3548720-714c-4199-b8d2-f6db29804ed9@cn.fujitsu.com>
Date: Mon, 3 Jul 2017 11:53:01 +0800
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Hi Thomas,

At 07/03/2017 03:18 AM, Thomas Gleixner wrote:
> On Fri, 30 Jun 2017, Dou Liyang wrote:
>
>> xen_smp_ops overwrites smp_prepare_cpus to xen_pv_smp_prepare_cpus
>> which initializes interrupt itself.
>>
>> Touching the intr_mode_init causes unexpected results on the system.
>>
>> Bypass it in enlighten_pv system.
>
> So that's the wrong patch order then. You broke XEN at some point with your
> changes. You need to prevent that breakage upfront not after the fact.

Yes, I have considered to prevent that breakage in the patchset.

Actually, Until the 11th patch, we put the intr_mode_init ahead of
time, which will break XEN.

Before the 11th patch, we just unify the code and do the preparation,
Kernel will do the intr_mode_init like before, which will have no
influence on XEN.

So we put the patch here before 11th patch.

Thanks,

	dou.

>
> Thanks,
>
> 	tglx
>
>
>