Messages in this thread | | | Subject | Re: Populating multiple ptes at fault time | From | Benjamin Herrenschmidt <> | Date | Fri, 19 Sep 2008 10:45:03 -0700 |
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On Wed, 2008-09-17 at 15:02 -0700, Avi Kivity wrote: > Jeremy Fitzhardinge wrote: > > Minor faults are easier; if the page already exists in memory, we should > > just create mappings to it. If neighbouring pages are also already > > present, then we can can cheaply create mappings for them too. > > > > > > One problem is the accessed bit. If it's unset, the shadow code cannot > make the pte present (since it has to trap in order to set the accessed > bit); if it's set, we're lying to the vm. > > This doesn't affect Xen, only kvm.
Other archs too. On powerpc, !accessed -> not hashed (or not in the TLB for SW loaded TLB platforms).
Ben.
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