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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<div class="moz-cite-prefix">On 11/10/13 15:11, 李德新
wrote:<br>
</div>
<blockquote
cite="mid:CAJHuRbQq0=xFhMk57jbKWmX1ahOPGeTpbUs=mWhhuVZ09PHFvQ@mail.gmail.com"
type="cite">
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<div><span style="font-family:"Times New
Roman","serif""
lang="EN-US">Hi,<br>
page->tlbflush_timestamp is used to filter and
flush the TLB whenever type change of page happens.
</span><span
style="font-family:"Times New
Roman","serif""
lang="EN-US">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. <br>
<br>
Thanks!<br>
<br>
Best regards,<br>
</span></div>
<span style="font-family:"Times New
Roman","serif""
lang="EN-US">Sam<br>
</span></div>
</blockquote>
<br>
The comment beside the code you reference explains why this is
required for safety.<br>
<br>
On a more pragmatic view however, there is no Xen can trust that
guest kernels are operating correctly.<br>
<br>
~Andrew<br>
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