KVM: MMU: init kvm generation close to mmio wrap-around value

Then it has the chance to trigger mmio generation number wrap-around

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Reviewed-by: Gleb Natapov <gleb@redhat.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
[Change from MMIO_MAX_GEN - 13 to MMIO_MAX_GEN - 150, because 13 is
 very close to the number of calls to KVM_SET_USER_MEMORY_REGION
 before the guest is started and there is any chance to create any
 spte. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Xiao Guangrong 2013-06-07 16:51:28 +08:00 committed by Gleb Natapov
parent 089504c0d4
commit 69c9ea93ea

View File

@ -235,7 +235,12 @@ static unsigned int get_mmio_spte_generation(u64 spte)
static unsigned int kvm_current_mmio_generation(struct kvm *kvm)
{
return kvm_memslots(kvm)->generation & MMIO_GEN_MASK;
/*
* Init kvm generation close to MMIO_MAX_GEN to easily test the
* code of handling generation number wrap-around.
*/
return (kvm_memslots(kvm)->generation +
MMIO_MAX_GEN - 150) & MMIO_GEN_MASK;
}
static void mark_mmio_spte(struct kvm *kvm, u64 *sptep, u64 gfn,