[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Xen-devel] Re: One potential issue of shadow fault emulation

At 21:54 +0000 on 21 Dec (1198274059), Keir Fraser wrote:
> Probably gfn_to_mfn() should explicitly check for vmx_apic_access_mfn and
> return INVALID_MFN instead. That will fix all emulation routines by causing
> them to take their mmio path (or bail if they don't have them) which is the
> correct behaviour for this case.

That will disable the VMX TPR optimization too -- the p2m lookup needs
to return this magic page when the shadow propagation code looks it up
but not when other callers look it up.  Maybe the existing scheme for
mapping MMIO pages directly would do; mark the page as direct MMIO
instead of as RAM?  Otherwise at least one of the shadow propagation
code and the emulator needs to special-case the vlapic page.



Tim Deegan <Tim.Deegan@xxxxxxxxxx>
Principal Software Engineer, Citrix Systems.
[Company #5334508: XenSource UK Ltd, reg'd c/o EC2Y 5EB, UK.]

Xen-devel mailing list



Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.