From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 487822F24 for ; Wed, 12 Apr 2023 08:43:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C7D1BC433EF; Wed, 12 Apr 2023 08:43:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1681288985; bh=4NaQuf6HihVjO1mq4DCwtHKv2a9ub7UUo9YN6IkEg+s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=A994V2YkE8+fr4qld7LU9IYUpzp6zwouWi6bvrrJ7XbpHYvUlGl2ubzTeoxANb9t/ aXBCSDMt5P3AFyhipH+AjtYM0fei2av7bB86Q1N9M6QLFuz22MjQulKuVcOIgRT3wd tkJLzWDiOrLvFmiKDNWXJRBO+y5WAuZSaCHagQHI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Maxim Levitsky , Sean Christopherson , Paolo Bonzini Subject: [PATCH 6.1 093/164] KVM: nVMX: Do not report error code when synthesizing VM-Exit from Real Mode Date: Wed, 12 Apr 2023 10:33:35 +0200 Message-Id: <20230412082840.641690214@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230412082836.695875037@linuxfoundation.org> References: <20230412082836.695875037@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Sean Christopherson commit 80962ec912db56d323883154efc2297473e692cb upstream. Don't report an error code to L1 when synthesizing a nested VM-Exit and L2 is in Real Mode. Per Intel's SDM, regarding the error code valid bit: This bit is always 0 if the VM exit occurred while the logical processor was in real-address mode (CR0.PE=0). The bug was introduced by a recent fix for AMD's Paged Real Mode, which moved the error code suppression from the common "queue exception" path to the "inject exception" path, but missed VMX's "synthesize VM-Exit" path. Fixes: b97f07458373 ("KVM: x86: determine if an exception has an error code only when injecting it.") Cc: stable@vger.kernel.org Cc: Maxim Levitsky Signed-off-by: Sean Christopherson Message-Id: <20230322143300.2209476-3-seanjc@google.com> Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/vmx/nested.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -3845,7 +3845,12 @@ static void nested_vmx_inject_exception_ exit_qual = 0; } - if (ex->has_error_code) { + /* + * Unlike AMD's Paged Real Mode, which reports an error code on #PF + * VM-Exits even if the CPU is in Real Mode, Intel VMX never sets the + * "has error code" flags on VM-Exit if the CPU is in Real Mode. + */ + if (ex->has_error_code && is_protmode(vcpu)) { /* * Intel CPUs do not generate error codes with bits 31:16 set, * and more importantly VMX disallows setting bits 31:16 in the