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Date: Wed, 4 Mar 2015 15:45:21 +0000
From: David Vrabel <david.vrabel@citrix.com>
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To: Boris Ostrovsky <boris.ostrovsky@oracle.com>, <paulmck@linux.vnet.ibm.com>
CC: <linux-kernel@vger.kernel.org>, <mingo@kernel.org>, <laijs@cn.fujitsu.com>,
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        <x86@kernel.org>, Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
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Subject: Re: [PATCH tip/core/rcu 02/20] x86: Use common outgoing-CPU-notification
 code
References: <20150303174144.GA13139@linux.vnet.ibm.com> <1425404595-17816-1-git-send-email-paulmck@linux.vnet.ibm.com> <1425404595-17816-2-git-send-email-paulmck@linux.vnet.ibm.com> <54F608C4.40405@oracle.com> <20150303194223.GR15405@linux.vnet.ibm.com> <54F615D3.2040802@oracle.com> <20150303212647.GZ15405@linux.vnet.ibm.com> <54F6307A.8040003@oracle.com> <20150303223151.GC15405@linux.vnet.ibm.com> <20150304144336.GA8225@linux.vnet.ibm.com> <54F71CCF.9050509@oracle.com>
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On 04/03/15 14:55, Boris Ostrovsky wrote:
> 
> In the meantime, it turned out that HVM guests are broken by this patch
> (with our without changes that we've been discussing), because HVM CPUs
> die with
> 
> static void xen_hvm_cpu_die(unsigned int cpu)
> {
>         xen_cpu_die(cpu);
>         native_cpu_die(cpu);
> }
> 
> Which means that cpu_wait_death() is called twice, and second call moves
> the CPU to CPU_BROKEN.
> 
> The simple solution is to stop calling native_cpu_die() above but I'd
> like to use common code in native_cpu_die(). I'll see if I can carve it
> out without too much damage to x86.

If not really been following this thread but...

Would it be preferable to refactor xen_cpu_die() instead to factor out
its the cpu_wait_death() call?

David