From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [IPv6:2a01:7e0:0:424::9]) by lore.proxmox.com (Postfix) with ESMTPS id 5214B1FF186 for ; Sat, 4 Oct 2025 15:24:10 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 5D2FB12722; Sat, 4 Oct 2025 15:23:25 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; t=1759331592; x=1759936392; d=canarybit.eu; s=rsa1; h=content-transfer-encoding:mime-version:references:in-reply-to:message-id:date: subject:cc:to:from:from; bh=cN5uLwBygxn2G+RYK2RWvVrglxPIGO9ODJTa+vsWGZo=; b=42mXLmqD4/UXHQN/rtmwgVhhBRCiXpP95NWf5ZVgBWFhBZPCgRXRla61ceriO4+zhx0R1ed7HA+cy ROkQInGZa62ZNXPWhXSeKr5GUNMqLUrvgeaTnONPo4ad34M4qkIT6ymhV82/uqLUVHr3/xRdbrHv/e fMAqNzRQ9w1d1k27L/3nrXOTXeSeqGJq1gBqYI0AqNBdtff93A2RA8KzphHeZjTdSTZraeP8B5coty b515L2wgppfJtNPOyOECYOgPMY4gmTdudFhnKuHSqnPfqIFcmVVcanaypLIxBGVM4flhkRmYeUws3o Ar1imwG0r1NpWDkwFkur6iqmb03+bag== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; t=1759331592; x=1759936392; d=canarybit.eu; s=ed1; h=content-transfer-encoding:mime-version:references:in-reply-to:message-id:date: subject:cc:to:from:from; bh=cN5uLwBygxn2G+RYK2RWvVrglxPIGO9ODJTa+vsWGZo=; b=2EcLDYBZ+bU3ZiAYxTpCAJc1jdtt0O8n5x9IDdSAWsU47/F41IrLzWGEFyyfZM9T3PIRQ09DqwPxW OmwUXLuDQ== X-HalOne-ID: 24c17904-9ed9-11f0-a6e3-fb5fec76084d From: Anton Iacobaeus To: pve-devel@lists.proxmox.com Date: Wed, 1 Oct 2025 17:11:19 +0200 Message-ID: <20251001151237.50385-7-anton.iacobaeus@canarybit.eu> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20251001151237.50385-1-anton.iacobaeus@canarybit.eu> References: <20251001151237.50385-1-anton.iacobaeus@canarybit.eu> MIME-Version: 1.0 X-SPAM-LEVEL: Spam detection results: 0 BAYES_00 -1.9 Bayes spam probability is 0 to 1% DKIM_SIGNED 0.1 Message has a DKIM or DK signature, not necessarily valid DKIM_VALID -0.1 Message has at least one valid DKIM or DK signature DKIM_VALID_AU -0.1 Message has a valid DKIM or DK signature from author's domain DKIM_VALID_EF -0.1 Message has a valid DKIM or DK signature from envelope-from domain DMARC_MISSING 0.1 Missing DMARC policy RCVD_IN_DNSWL_NONE -0.0001 Sender listed at https://www.dnswl.org/, no trust SPF_HELO_PASS -0.001 SPF: HELO matches SPF record SPF_NONE 0.001 SPF: sender does not publish an SPF Record X-Mailman-Approved-At: Sat, 04 Oct 2025 15:23:21 +0200 Subject: [pve-devel] [PATCH qemu-server v2 2/3] Add check for TDX support X-BeenThere: pve-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE development discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Proxmox VE development discussion Cc: Philipp Giersfeld Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: pve-devel-bounces@lists.proxmox.com Sender: "pve-devel" From: Philipp Giersfeld Check whether TDX is enabled on this machine. Instead of using CPUID like AMD SEV, Intel TDX enablement can be verified by reading an MSR (https://cc-enabling.trustedservices.intel.com/intel-tdx-enabling-guide/05/host_os_setup/). Signed-off-by: Philipp Giersfeld Signed-off-by: Anton Iacobaeus --- .../query-machine-capabilities.c | 97 ++++++++++++++++--- src/usr/modules-load.conf | 1 + 2 files changed, 85 insertions(+), 13 deletions(-) diff --git a/src/query-machine-capabilities/query-machine-capabilities.c b/src/query-machine-capabilities/query-machine-capabilities.c index 0c522afc..5bc39450 100644 --- a/src/query-machine-capabilities/query-machine-capabilities.c +++ b/src/query-machine-capabilities/query-machine-capabilities.c @@ -4,6 +4,8 @@ #include #include #include +#include +#include #define eprintf(...) fprintf(stderr, __VA_ARGS__) @@ -18,17 +20,56 @@ typedef struct { uint8_t cbitpos; uint8_t reduced_phys_bits; -} cpu_caps_t; +} cpu_caps_amd_sev_t; -void query_cpu_capabilities(cpu_caps_t *res) { +typedef struct { + bool tdx_support; +} cpu_caps_intel_tdx_t; + +int read_msr(uint32_t msr_index, unsigned int *value) { + int64_t data; + char* msr_file_name = "/dev/cpu/0/msr"; + int fd; + + fd = open(msr_file_name, O_RDONLY); + if (fd < 0) { + if (errno == ENXIO) { + eprintf("rdmsr: No CPU 0\n"); + return -1; + } else if (errno == EIO) { + eprintf("rdmsr: CPU doesn't support MSRs\n"); + return -1; + } else { + perror("rdmsr: failed to open MSR"); + return -1; + } + } + + if (pread(fd, &data, sizeof data, msr_index) != sizeof data) { + if (errno == EIO) { + eprintf("rdmsr: CPU cannot read MSR 0x%08x\n", msr_index); + return -1; + } else { + perror("rdmsr: pread"); + return -1; + } + } + + *value = data; + + close(fd); + return 0; +} + +void query_cpu_capabilities_sev(cpu_caps_amd_sev_t *res) { uint32_t eax, ebx, ecx, edx; // query Encrypted Memory Capabilities, see: // https://en.wikipedia.org/wiki/CPUID#EAX=8000001Fh:_Encrypted_Memory_Capabilities uint32_t query_function = 0x8000001F; asm volatile("cpuid" - : "=a"(eax), "=b"(ebx), "=c"(ecx), "=d"(edx) - : "0"(query_function) + : "=a"(eax), "=b"(ebx), "=c"(ecx), "=d"(edx) + : "0"(query_function) ); res->sev_support = (eax & (1<<1)) != 0; @@ -39,6 +80,18 @@ void query_cpu_capabilities(cpu_caps_t *res) { res->reduced_phys_bits = (ebx >> 6) & 0x3f; } +int query_cpu_capabilities_tdx(cpu_caps_intel_tdx_t *res) { + unsigned int value; + + if (read_msr(0x1401, &value) == 0) { + res->tdx_support = (value & (1<<11)); + } else { + eprintf("Error reading MSR, Intel TDX support undetermined\n"); + return -1; + } + return 0; +} + int prepare_output_directory() { // Check that the directory exists and create it if it does not. struct stat statbuf; @@ -65,8 +118,8 @@ int main() { return 1; } - cpu_caps_t caps; - query_cpu_capabilities(&caps); + cpu_caps_amd_sev_t caps_sev; + query_cpu_capabilities_sev(&caps_sev); FILE *file = fopen(OUTPUT_PATH, "w"); if (file == NULL) { @@ -82,18 +135,36 @@ int main() { " \"sev-support\": %s," " \"sev-support-es\": %s," " \"sev-support-snp\": %s" - " }" - " }\n", - caps.cbitpos, - caps.reduced_phys_bits, - caps.sev_support ? "true" : "false", - caps.sev_es_support ? "true" : "false", - caps.sev_snp_support ? "true" : "false" + " }", + caps_sev.cbitpos, + caps_sev.reduced_phys_bits, + caps_sev.sev_support ? "true" : "false", + caps_sev.sev_es_support ? "true" : "false", + caps_sev.sev_snp_support ? "true" : "false" ); if (ret < 0) { eprintf("Error writing to file '" OUTPUT_PATH "': %s\n", strerror(errno)); } + cpu_caps_intel_tdx_t caps_tdx; + if (query_cpu_capabilities_tdx(&caps_tdx) == 0) { + ret = fprintf(file, + "," + " \"intel-tdx\": {" + " \"tdx-support\": %s" + " }", + caps_tdx.tdx_support ? "true" : "false" + ); + if (ret < 0) { + eprintf("Error writing to file '" OUTPUT_PATH "': %s\n", strerror(errno)); + } + } + + ret = fprintf(file, " }\n"); + if (ret < 0) { + eprintf("Error writing to file '" OUTPUT_PATH "': %s\n", strerror(errno)); + } + ret = fclose(file); if (ret != 0) { eprintf("Error closing file '" OUTPUT_PATH "': %s\n", strerror(errno)); diff --git a/src/usr/modules-load.conf b/src/usr/modules-load.conf index aee7d42a..f45d256b 100644 --- a/src/usr/modules-load.conf +++ b/src/usr/modules-load.conf @@ -1 +1,2 @@ vhost_net +msr -- 2.43.0 _______________________________________________ pve-devel mailing list pve-devel@lists.proxmox.com https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel