@@ -215,6 +215,18 @@ static inline void kvm_set_s2pte_readonly(pte_t *ptep)
} while (pteval != old_pteval);
}
+static inline void kvm_set_s2pte_young(pte_t *ptep)
+{
+ pteval_t old_pteval, pteval;
+
+ pteval = READ_ONCE(pte_val(*ptep));
+ do {
+ old_pteval = pteval;
+ pteval |= PTE_AF;
+ pteval = cmpxchg_relaxed(&pte_val(*ptep), old_pteval, pteval);
+ } while (pteval != old_pteval);
+}
+
static inline bool kvm_s2pte_readonly(pte_t *ptep)
{
return (READ_ONCE(pte_val(*ptep)) & PTE_S2_RDWR) == PTE_S2_RDONLY;
@@ -230,6 +242,11 @@ static inline void kvm_set_s2pmd_readonly(pmd_t *pmdp)
kvm_set_s2pte_readonly((pte_t *)pmdp);
}
+static inline void kvm_set_s2pmd_young(pmd_t *pmdp)
+{
+ kvm_set_s2pte_young((pte_t *)pmdp);
+}
+
static inline bool kvm_s2pmd_readonly(pmd_t *pmdp)
{
return kvm_s2pte_readonly((pte_t *)pmdp);
@@ -245,6 +262,11 @@ static inline void kvm_set_s2pud_readonly(pud_t *pudp)
kvm_set_s2pte_readonly((pte_t *)pudp);
}
+static inline void kvm_set_s2pud_young(pud_t *pudp)
+{
+ kvm_set_s2pte_young((pte_t *)pudp);
+}
+
static inline bool kvm_s2pud_readonly(pud_t *pudp)
{
return kvm_s2pte_readonly((pte_t *)pudp);
@@ -255,16 +277,6 @@ static inline bool kvm_s2pud_exec(pud_t *pudp)
return !(READ_ONCE(pud_val(*pudp)) & PUD_S2_XN);
}
-static inline pud_t kvm_s2pud_mkyoung(pud_t pud)
-{
- return pud_mkyoung(pud);
-}
-
-static inline bool kvm_s2pud_young(pud_t pud)
-{
- return pud_young(pud);
-}
-
#ifdef CONFIG_ARM64_HW_AFDBM
static inline bool kvm_hw_dbm_enabled(void)
{
@@ -2008,8 +2008,9 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
* Resolve the access fault by making the page young again.
* Note that because the faulting entry is guaranteed not to be
* cached in the TLB, we don't need to invalidate anything.
- * Only the HW Access Flag updates are supported for Stage 2 (no DBM),
- * so there is no need for atomic (pte|pmd)_mkyoung operations.
+ *
+ * Note: Both DBM and HW AF updates are supported for Stage2, so
+ * young operations should be atomic.
*/
static void handle_access_fault(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa)
{
@@ -2027,15 +2028,15 @@ static void handle_access_fault(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa)
goto out;
if (pud) { /* HugeTLB */
- *pud = kvm_s2pud_mkyoung(*pud);
+ kvm_set_s2pud_young(pud);
pfn = kvm_pud_pfn(*pud);
pfn_valid = true;
} else if (pmd) { /* THP, HugeTLB */
- *pmd = pmd_mkyoung(*pmd);
+ kvm_set_s2pmd_young(pmd);
pfn = pmd_pfn(*pmd);
pfn_valid = true;
- } else {
- *pte = pte_mkyoung(*pte); /* Just a page... */
+ } else { /* Just a page... */
+ kvm_set_s2pte_young(pte);
pfn = pte_pfn(*pte);
pfn_valid = true;
}
@@ -2280,7 +2281,7 @@ static int kvm_test_age_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *
return 0;
if (pud)
- return kvm_s2pud_young(*pud);
+ return pud_young(*pud);
else if (pmd)
return pmd_young(*pmd);
else
Marking PTs young (set AF bit) should be atomic to avoid cover dirty status set by hardware. Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com> --- arch/arm64/include/asm/kvm_mmu.h | 32 ++++++++++++++++++++++---------- arch/arm64/kvm/mmu.c | 15 ++++++++------- 2 files changed, 30 insertions(+), 17 deletions(-)