Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 5d218814 authored by Marcelo Tosatti's avatar Marcelo Tosatti Committed by Gleb Natapov
Browse files

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 f0f5933a),
resulting in n_used_mmu_pages > n_max_mmu_pages.

Make code robust against n_used_mmu_pages > n_max_mmu_pages.

Reviewed-by: default avatarXiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: default avatarGleb Natapov <gleb@redhat.com>
parent 57f252f2

arch/x86/kvm/mmu.h

+5 −2
Original line number Diff line number Diff line
@@ -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)

{

	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)