From: Sean Christopherson <seanjc@xxxxxxxxxx>
Tweak KVM_MMU_ROOTS_ALL to precisely cover all current+previous root
flags, and add a sanity in kvm_mmu_free_roots() to verify that the set
of roots to free doesn't stray outside KVM_MMU_ROOTS_ALL.
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Signed-off-by: Lai Jiangshan <jiangshan.ljs@xxxxxxxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 8 ++++----
arch/x86/kvm/mmu/mmu.c | 2 ++
2 files changed, 6 insertions(+), 4 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index b71b52fdb5ee..5bd91c49c8b3 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -422,6 +422,10 @@ struct kvm_mmu_root_info {
#define KVM_MMU_NUM_PREV_ROOTS 3
+#define KVM_MMU_ROOT_CURRENT BIT(0)
+#define KVM_MMU_ROOT_PREVIOUS(i) BIT(1+i)
+#define KVM_MMU_ROOTS_ALL (BIT(1 + KVM_MMU_NUM_PREV_ROOTS) - 1)
+
#define KVM_HAVE_MMU_RWLOCK
struct kvm_mmu_page;
@@ -1978,10 +1982,6 @@ static inline int __kvm_irq_line_state(unsigned long *irq_state,
return !!(*irq_state);
}
-#define KVM_MMU_ROOT_CURRENT BIT(0)
-#define KVM_MMU_ROOT_PREVIOUS(i) BIT(1+i)
-#define KVM_MMU_ROOTS_ALL (~0UL)
-
int kvm_pic_set_irq(struct kvm_pic *pic, int irq, int irq_source_id, int level);
void kvm_pic_clear_all(struct kvm_pic *pic, int irq_source_id);
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index a8231b73ad4d..a4793cb8d64a 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -3568,6 +3568,8 @@ void kvm_mmu_free_roots(struct kvm *kvm, struct kvm_mmu *mmu,
LIST_HEAD(invalid_list);
bool free_active_root;
+ WARN_ON_ONCE(roots_to_free & ~KVM_MMU_ROOTS_ALL);
+
BUILD_BUG_ON(KVM_MMU_NUM_PREV_ROOTS >= BITS_PER_LONG);
/* Before acquiring the MMU lock, see if we need to do any real work. */
--
2.19.1.6.gb485710b
