From: Andrew Cooper <andrew.cooper3@citrix.com>
To: 李德新 <topcoder9@gmail.com>
Cc: xen-devel@lists.xen.org
Subject: Re: page->tlbflush_timestamp
Date: Fri, 11 Oct 2013 15:17:29 +0100 [thread overview]
Message-ID: <52580879.9090106@citrix.com> (raw)
In-Reply-To: <CAJHuRbQq0=xFhMk57jbKWmX1ahOPGeTpbUs=mWhhuVZ09PHFvQ@mail.gmail.com>
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On 11/10/13 15:11, 李德新 wrote:
> Hi,
> page->tlbflush_timestamp is used to filter and flush the TLB
> whenever type change of page happens. But why does xen flush TLB upon
> the type change? And we already know that guest kernel will flush the
> TLB in order to make the page table modifications take effect.
>
> Thanks!
>
> Best regards,
> Sam
The comment beside the code you reference explains why this is required
for safety.
On a more pragmatic view however, there is no Xen can trust that guest
kernels are operating correctly.
~Andrew
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prev parent reply other threads:[~2013-10-11 14:17 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-10-11 14:11 page->tlbflush_timestamp 李德新
2013-10-11 14:16 ` page->tlbflush_timestamp Jan Beulich
2013-10-11 14:17 ` Andrew Cooper [this message]
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