Re: [PATCH 2/2] KVM: nVMX: fix nEPT handling of guest page table accesses

2017-05-12 Thread Paolo Bonzini
On 12/05/2017 09:38, Xiao Guangrong wrote: > CC Kevin as i am not sure if Intel is aware of this issue, it > breaks other hypervisors, e.g, Xen, as swell. It's actually more complicated. When EPT A/D bits are disabled, reads of the page tables behave as described in the manual; writes have both b

Re: [PATCH 2/2] KVM: nVMX: fix nEPT handling of guest page table accesses

2017-05-12 Thread Xiao Guangrong
CC Kevin as i am not sure if Intel is aware of this issue, it breaks other hypervisors, e.g, Xen, as swell. On 05/11/2017 07:23 PM, Paolo Bonzini wrote: The new ept_access_test_paddr_read_only_ad_disabled testcase caused an infinite stream of EPT violations because KVM did not find anything bad

[PATCH 2/2] KVM: nVMX: fix nEPT handling of guest page table accesses

2017-05-11 Thread Paolo Bonzini
The new ept_access_test_paddr_read_only_ad_disabled testcase caused an infinite stream of EPT violations because KVM did not find anything bad in the page tables and kept re-executing the faulting instruction. This is because the exit qualification said we were reading from the page tables, but ac