Date:   Wed, 10 Nov 2021 14:29:52 -0800
In-Reply-To: <20211110223010.1392399-1-bgardon@google.com>
Message-Id: <20211110223010.1392399-2-bgardon@google.com>
Mime-Version: 1.0
References: <20211110223010.1392399-1-bgardon@google.com>
Subject: [RFC 01/19] KVM: x86/mmu: Fix TLB flush range when handling
 disconnected pt
From:   Ben Gardon <bgardon@google.com>
To:     linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc:     Paolo Bonzini <pbonzini@redhat.com>, Peter Xu <peterx@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        Peter Shier <pshier@google.com>,
        David Matlack <dmatlack@google.com>,
        Mingwei Zhang <mizhang@google.com>,
        Yulei Zhang <yulei.kernel@gmail.com>,
        Wanpeng Li <kernellwp@gmail.com>,
        Xiao Guangrong <xiaoguangrong.eric@gmail.com>,
        Kai Huang <kai.huang@intel.com>,
        Keqian Zhu <zhukeqian1@huawei.com>,
        David Hildenbrand <david@redhat.com>,
        Ben Gardon <bgardon@google.com>, stable@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

When recursively clearing out disconnected pts, the range based TLB
flush in handle_removed_tdp_mmu_page uses the wrong starting GFN,
resulting in the flush mostly missing the affected range. Fix this by
using base_gfn for the flush.

Fixes: a066e61f13cf ("KVM: x86/mmu: Factor out handling of removed page tables")
CC: stable@vger.kernel.org

Signed-off-by: Ben Gardon <bgardon@google.com>
---
 arch/x86/kvm/mmu/tdp_mmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 7c5dd83e52de..866c2b191e1e 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -374,7 +374,7 @@ static void handle_removed_tdp_mmu_page(struct kvm *kvm, tdp_ptep_t pt,
 				    shared);
 	}
 
-	kvm_flush_remote_tlbs_with_address(kvm, gfn,
+	kvm_flush_remote_tlbs_with_address(kvm, base_gfn,
 					   KVM_PAGES_PER_HPAGE(level + 1));
 
 	call_rcu(&sp->rcu_head, tdp_mmu_free_sp_rcu_callback);
-- 
2.34.0.rc0.344.g81b53c2807-goog