From: Avi Kivity <avi@redhat.com>
To: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>,
LKML <linux-kernel@vger.kernel.org>,
KVM list <kvm@vger.kernel.org>
Subject: Re: [PATCH v5 6/9] KVM: MMU: introduce pte_prefetch_topup_memory_cache()
Date: Tue, 13 Jul 2010 09:05:18 +0300 [thread overview]
Message-ID: <4C3C021E.1000709@redhat.com> (raw)
In-Reply-To: <4C3BFE12.4060009@cn.fujitsu.com>
On 07/13/2010 08:48 AM, Xiao Guangrong wrote:
>
>> Right. We should fix those too.
>>
>> Prefetch is much more worrying though, especially with ept. If a guest
>> is using just 1/8 of the pages, it can look to migration as if it's
>> using 100% of the pages. The impact can be pretty large.
>>
> We disabled prefetch if ept is enabled since it can break access bit tracking.
>
Oh yes.
> I'll fix the dirty bit tracking before post the new version of this patchset.
>
Should be simple - disable prefetch for slots that have dirty tracking
enabled.
What about the Linux accessed and dirty bits? Need to instantiate the
speculative sptes with accessed and dirty bits clear (and later examine
them when we release the page).
--
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.
next prev parent reply other threads:[~2010-07-13 6:05 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-07-06 10:44 [PATCH v5 1/9] KVM: MMU: fix forgot reserved bits check in speculative path Xiao Guangrong
2010-07-06 10:45 ` [PATCH v5 2/9] KVM: MMU: fix race between 'walk_addr' and 'fetch' Xiao Guangrong
2010-07-06 10:46 ` [PATCH v5 3/9] export __get_user_pages_fast() function Xiao Guangrong
2010-07-11 12:52 ` [PATCH v5 2/9] KVM: MMU: fix race between 'walk_addr' and 'fetch' Avi Kivity
2010-07-11 15:40 ` Avi Kivity
2010-07-06 10:47 ` [PATCH v5 4/9] KVM: MMU: introduce gfn_to_pfn_atomic() function Xiao Guangrong
2010-07-06 11:22 ` Gleb Natapov
2010-07-06 11:28 ` Xiao Guangrong
2010-07-09 1:34 ` Xiao Guangrong
2010-07-06 10:48 ` [PATCH v5 5/9] KVM: MMU: introduce gfn_to_page_many_atomic() function Xiao Guangrong
2010-07-11 12:59 ` Avi Kivity
2010-07-12 2:55 ` Xiao Guangrong
2010-07-12 12:28 ` Avi Kivity
2010-07-13 1:17 ` Xiao Guangrong
2010-07-06 10:49 ` [PATCH v5 6/9] KVM: MMU: introduce pte_prefetch_topup_memory_cache() Xiao Guangrong
2010-07-11 13:05 ` Avi Kivity
2010-07-12 3:05 ` Xiao Guangrong
2010-07-12 12:26 ` Avi Kivity
2010-07-13 1:16 ` Xiao Guangrong
2010-07-13 4:21 ` Avi Kivity
2010-07-13 4:25 ` Xiao Guangrong
2010-07-13 5:35 ` Avi Kivity
2010-07-13 5:48 ` Xiao Guangrong
2010-07-13 6:05 ` Avi Kivity [this message]
2010-07-13 6:10 ` Xiao Guangrong
2010-07-13 6:29 ` Avi Kivity
2010-07-13 6:52 ` Xiao Guangrong
2010-07-13 7:45 ` Avi Kivity
2010-07-06 10:50 ` [PATCH v5 7/9] KVM: MMU: prefetch ptes when intercepted guest #PF Xiao Guangrong
2010-07-06 10:51 ` [PATCH v5 8/9] KVM: MMU: combine guest pte read between fetch and pte prefetch Xiao Guangrong
2010-07-06 19:52 ` Marcelo Tosatti
2010-07-07 1:23 ` Xiao Guangrong
2010-07-07 13:07 ` Marcelo Tosatti
2010-07-07 13:11 ` Xiao Guangrong
2010-07-07 13:40 ` Marcelo Tosatti
2010-07-07 14:10 ` Xiao Guangrong
2010-07-07 15:30 ` Marcelo Tosatti
2010-07-06 10:52 ` [PATCH v5 9/9] KVM: MMU: trace " Xiao Guangrong
2010-07-11 12:24 ` [PATCH v5 1/9] KVM: MMU: fix forgot reserved bits check in speculative path Avi Kivity
2010-07-12 2:37 ` Xiao Guangrong
2010-07-12 13:15 ` Avi Kivity
2010-07-13 1:57 ` Xiao Guangrong
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