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[213.175.37.10]) by smtp.gmail.com with ESMTPSA id s5sm32248504wru.39.2020.03.03.06.33.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 03 Mar 2020 06:33:19 -0800 (PST) From: Vitaly Kuznetsov To: Paolo Bonzini , kvm@vger.kernel.org Cc: Jim Mattson , Sean Christopherson , Bandan Das , Oliver Upton , linux-kernel@vger.kernel.org Subject: [PATCH 1/2] KVM: x86: clear stale x86_emulate_ctxt->intercept value Date: Tue, 3 Mar 2020 15:33:15 +0100 Message-Id: <20200303143316.834912-2-vkuznets@redhat.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200303143316.834912-1-vkuznets@redhat.com> References: <20200303143316.834912-1-vkuznets@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit c44b4c6ab80e ("KVM: emulate: clean up initializations in init_decode_cache") reduced the number of fields cleared by init_decode_cache() claiming that they are being cleared elsewhere, 'intercept', however, seems to be left uncleared in some cases. The issue I'm observing manifests itself as following: after commit 07721feee46b ("KVM: nVMX: Don't emulate instructions in guest mode") Hyper-V guests on KVM stopped booting with: kvm_nested_vmexit: rip fffff802987d6169 reason EPT_VIOLATION info1 181 info2 0 int_info 0 int_info_err 0 kvm_page_fault: address febd0000 error_code 181 kvm_emulate_insn: 0:fffff802987d6169: f3 a5 kvm_emulate_insn: 0:fffff802987d6169: f3 a5 FAIL kvm_inj_exception: #UD (0x0) Fixes: c44b4c6ab80e ("KVM: emulate: clean up initializations in init_decode_cache") Fixes: 07721feee46b ("KVM: nVMX: Don't emulate instructions in guest mode") Cc: stable@vger.kernel.org Suggested-by: Paolo Bonzini Signed-off-by: Vitaly Kuznetsov --- arch/x86/kvm/emulate.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index dd19fb3539e0..bc00642e5d3b 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -5173,6 +5173,7 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len) ctxt->fetch.ptr = ctxt->fetch.data; ctxt->fetch.end = ctxt->fetch.data + insn_len; ctxt->opcode_len = 1; + ctxt->intercept = x86_intercept_none; if (insn_len > 0) memcpy(ctxt->fetch.data, insn, insn_len); else { -- 2.24.1