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 C280A2E1C74; Tue, 8 Jul 2025 17:03:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751994197; cv=none; b=M3xjygsUWmEysDco7/wo9dPSKqOS7WdKczXDA5oTKJF6T4JJ1pQEV8xIkUsVeIslagzXIMgQVlGpIebHhr9v+fbOlKL0yGzYy6hhgjRG/UW4rPpoJe6MiThcBQlNc9egO/pYzfm2GlNs2JQneuKJ3dWioovjJlNHxXN2Ujzwb9E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751994197; c=relaxed/simple; bh=+A+NWHpuAhIZpmyumxbzYUcUFFjGumTfrfscF7lvt/I=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=upv4jLqx7GmZc1FaO2CBFaGxeXjq9MJAe2BKfCrl7uW0EWtKj096IGVDGbI4Qjmu3OxptFfZVBvQc9Yzgop6ZaAc8kd6ygphGtKsd+r2x/sTMBmWWqzy+JUrbnW2yYt2ApH6jvXonrD44846MruFDhiXcP8OEZplHuMT5ZcahXo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=DFjY2kiA; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="DFjY2kiA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4AA14C4CEED; Tue, 8 Jul 2025 17:03:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1751994197; bh=+A+NWHpuAhIZpmyumxbzYUcUFFjGumTfrfscF7lvt/I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DFjY2kiASbwceOlql36NWQd2xWdYlaGlcQ2cjTxTHNoS+KQ1vI/dqJVAugjOHgrwr P6Nu+caRzFz0OwlmJCMroFUrI13Tcd03TkebfSZ+t2l5mqDq+2jxmT6eQHuagadISw prhCfm4i7cs32OSiw8Rn2rPq8QTflux9jR65ZQsI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Paolo Bonzini , "Borislav Petkov (AMD)" Subject: [PATCH 5.15 158/160] KVM: x86: add support for CPUID leaf 0x80000021 Date: Tue, 8 Jul 2025 18:23:15 +0200 Message-ID: <20250708162235.671662565@linuxfoundation.org> X-Mailer: git-send-email 2.50.0 In-Reply-To: <20250708162231.503362020@linuxfoundation.org> References: <20250708162231.503362020@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Paolo Bonzini Commit 58b3d12c0a860cda34ed9d2378078ea5134e6812 upstream. CPUID leaf 0x80000021 defines some features (or lack of bugs) of AMD processors. Expose the ones that make sense via KVM_GET_SUPPORTED_CPUID. Signed-off-by: Paolo Bonzini Signed-off-by: Borislav Petkov (AMD) Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/cpuid.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -915,7 +915,7 @@ static inline int __do_cpuid_func(struct entry->edx = 0; break; case 0x80000000: - entry->eax = min(entry->eax, 0x8000001f); + entry->eax = min(entry->eax, 0x80000021); break; case 0x80000001: entry->ebx &= ~GENMASK(27, 16); @@ -995,6 +995,23 @@ static inline int __do_cpuid_func(struct entry->ebx &= ~GENMASK(11, 6); } break; + case 0x80000020: + entry->eax = entry->ebx = entry->ecx = entry->edx = 0; + break; + case 0x80000021: + entry->ebx = entry->ecx = entry->edx = 0; + /* + * Pass down these bits: + * EAX 0 NNDBP, Processor ignores nested data breakpoints + * EAX 2 LAS, LFENCE always serializing + * EAX 6 NSCB, Null selector clear base + * + * Other defined bits are for MSRs that KVM does not expose: + * EAX 3 SPCL, SMM page configuration lock + * EAX 13 PCMSR, Prefetch control MSR + */ + entry->eax &= BIT(0) | BIT(2) | BIT(6); + break; /*Add support for Centaur's CPUID instruction*/ case 0xC0000000: /*Just support up to 0xC0000004 now*/