From dfcc47a1fe36d5508f502676ae387086c0e490e3 Mon Sep 17 00:00:00 2001
From: Chenyi Qiang <chenyi.qiang@intel.com>
Date: Thu, 21 Oct 2021 15:10:22 +0800
Subject: [PATCH] KVM: MMU: Reset mmu->pkru_mask to avoid stale data
Git-commit: a3ca5281bb771d8103ea16f0a6a8a5df9a7fb4f3
Patch-mainline: v5.15-rc7
References: stable-5.14.15
commit a3ca5281bb771d8103ea16f0a6a8a5df9a7fb4f3 upstream.
When updating mmu->pkru_mask, the value can only be added but it isn't
reset in advance. This will make mmu->pkru_mask keep the stale data.
Fix this issue.
Fixes: 2d344105f57c ("KVM, pkeys: introduce pkru_mask to cache conditions")
Signed-off-by: Chenyi Qiang <chenyi.qiang@intel.com>
Message-id: <20211021071022.1140-1-chenyi.qiang@intel.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
arch/x86/kvm/mmu/mmu.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index c268fb59f779..6719a8041f59 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4465,10 +4465,10 @@ static void update_pkru_bitmask(struct kvm_mmu *mmu)
unsigned bit;
bool wp;
- if (!is_cr4_pke(mmu)) {
- mmu->pkru_mask = 0;
+ mmu->pkru_mask = 0;
+
+ if (!is_cr4_pke(mmu))
return;
- }
wp = is_cr0_wp(mmu);
--
2.26.2