redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

KVM: MMU: make kvm_mmu_available_pages robust against n_used_mmu_pages > n_max_mmu_pages 

As noticed by Ulrich Obergfell <uobergfe@redhat.com>, the mmu
counters are for beancounting purposes only - so n_used_mmu_pages and
n_max_mmu_pages could be relaxed (example: before f0f5933a16),
resulting in n_used_mmu_pages > n_max_mmu_pages.

Make code robust against n_used_mmu_pages > n_max_mmu_pages.

Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
hifive-unleashed-5.1
Marcelo Tosatti 2013-03-12 22:36:43 -03:00 committed by Gleb Natapov
parent 57f252f229
commit 5d21881432
1 changed files with 5 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
arch/x86/kvm/mmu.h
View File

@ -57,8 +57,11 @@ int kvm_init_shadow_mmu(struct kvm_vcpu *vcpu, struct kvm_mmu *context);
static inline unsigned int kvm_mmu_available_pages(struct kvm *kvm)
{
return kvm->arch.n_max_mmu_pages -
kvm->arch.n_used_mmu_pages;
if (kvm->arch.n_max_mmu_pages > kvm->arch.n_used_mmu_pages)
return kvm->arch.n_max_mmu_pages -
kvm->arch.n_used_mmu_pages;
return 0;
}
static inline void kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu)