diff mbox series

[v2,1/8] KVM: arm64: Set DBM bit for writable PTEs

Message ID 20200702135556.36896-2-zhukeqian1@huawei.com (mailing list archive)
State New, archived
Headers show
Series KVM: arm64: Support HW dirty log based on DBM | expand

Commit Message

zhukeqian July 2, 2020, 1:55 p.m. UTC 
DBM bit is used by MMU to differentiate a genuinely non-writable
page from a page that is only temporarily non-writable in order
to mark dirty.

Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com>
Signed-off-by: Peng Liang <liangpeng10@huawei.com>
---
 arch/arm64/include/asm/kvm_mmu.h | 4 ++++
 1 file changed, 4 insertions(+)
diff mbox series

Patch

diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
index b12bfc1f051a..2700442b0f75 100644
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -169,6 +169,10 @@  void kvm_clear_hyp_idmap(void);
 static inline pte_t kvm_s2pte_mkwrite(pte_t pte)
 {
 	pte_val(pte) |= PTE_S2_RDWR;
+
+	if (IS_ENABLED(CONFIG_ARM64_HW_AFDBM))
+		pte_val(pte) |= PTE_DBM;
+
 	return pte;
 }