From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.xen@gmail.com>
Subject: Re: use tasklet to handle init/sipi?
Date: Tue, 26 Mar 2013 07:00:47 +0000
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To: "Zhang, Yang Z" <yang.z.zhang@intel.com>, "xen-devel@lists.xen.org" <xen-devel@lists.xen.org>
Cc: "Qiu, Shuang" <shuang.qiu@intel.com>, "Zhang,
	Xiantao" <xiantao.zhang@intel.com>, Jan Beulich <jbeulich@suse.com>
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On 26/03/2013 06:14, "Zhang, Yang Z" <yang.z.zhang@intel.com> wrote:

>> You'll have t elaborate on the problem *you* are trying to solve, and why
>> such a change would do the trick. If there's good reason, I'm not against a
>> change such as this. But the code is subtle and I don't want to mess with it
>> if there are simpler solutions.
> The problem is:
> With apicv support, the apic write is trap like vmexit. We cannot fallback to
> guest to retry the instruction. So it will break current logic.

Oh, I see. Well I think it is fine to have
vlapic_schedule_init_sipi_tasklet() return X86EMUL_OKAY rather than
X86EMUL_RETRY. We used to need to return RETRY, but the code got simplified
and now it is actually unnecessary.

That should make your patch a lot simpler eh? ;)

 -- Keir