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From: Keir Fraser <keir@xen.org>
To: Jan Beulich <JBeulich@novell.com>, Gang Wei <gang.wei@intel.com>
Cc: "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>
Subject: Re: [PATCH] Allow dom0 to write MSR IA32_ENERGY_PERF_BIAS
Date: Wed, 05 Jan 2011 08:22:46 +0000	[thread overview]
Message-ID: <C949DAD6.1102B%keir@xen.org> (raw)
In-Reply-To: <4D24371B020000780002A62B@vpn.id2.novell.com>

On 05/01/2011 08:17, "Jan Beulich" <JBeulich@novell.com> wrote:

>>>> On 05.01.11 at 09:13, Keir Fraser <keir.fraser@eu.citrix.com> wrote:
>> On 05/01/2011 07:59, "Jan Beulich" <JBeulich@novell.com> wrote:
>> 
>>>>> Why would you allow this only if Dom0 has its vcpus pinned?
>>>> 
>>>> It is meaningless if dom0 can't control all pcpus exactly. Only in case of
>>>> dom0 vcpus pinned, it makes sense.
>>> 
>>> Disagree. The user mode tool could set its own affinity (virtual and
>>> physical) and then issue the MSR write. Please don't enforce
>>> restrictions where not really needed (I actually suppose that the
>>> restriction should be removed for MSR_IA32_THERM_CONTROL too).
>> 
>> If so, it deserves a separate patch to strip out *all* the is_pinned checks
>> at the same time.
> 
> You certainly don't mean *all*, but yes, I'm intending to submit such
> a patch.

The ones in x86/traps.c (WRMSR emulation) and x86/domain.c
(VCPUOP_get_physid) are both unnecessary, at least.

 -- Keir

> Jan
> 
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel

  reply	other threads:[~2011-01-05  8:22 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-01-04  3:04 [PATCH] Allow dom0 to write MSR IA32_ENERGY_PERF_BIAS Wei, Gang
2011-01-04  9:58 ` Jan Beulich
2011-01-05  2:08   ` Wei, Gang
2011-01-05  7:59     ` Jan Beulich
2011-01-05  8:13       ` Keir Fraser
2011-01-05  8:17         ` Jan Beulich
2011-01-05  8:22           ` Keir Fraser [this message]
2011-01-05  8:31             ` Jan Beulich
2011-01-05  8:55               ` Wei, Gang
2011-01-05  9:03                 ` Jan Beulich

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