Re: One (possible) x86 get_user_pages bug

[Avi Kivity]

On 01/27/2011 08:27 PM, Jeremy Fitzhardinge wrote:
> And even just considering virtualization, having non-IPI-based tlb
> shootdown is a measurable performance win, since a hypervisor can
> optimise away a cross-VCPU shootdown if it knows no physical TLB
> contains the target VCPU's entries.  I can imagine the KVM folks could
> get some benefit from that as well.

It's nice to avoid the IPI (and waking up a cpu if it happens to be 
asleep) but I think the risk of deviating too much from the baremetal 
arch is too large, as demonstrated by this bug.

(well, async page faults is a counterexample, I wonder if/when it will 
bite us)

--
error compiling committee.c: too many arguments to function

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