AI Trajectory

null

{
  "EnableConfigs": null,
  "FocusSymbols": [],
  "Reasoning": "The patch refactors TDX global metadata reading in the TDX host initialization code (arch/x86/virt/vmx/tdx/tdx.c). This code requires physical Intel TDX hardware, specifically the X86_FEATURE_TDX_HOST_PLATFORM CPU feature and the SEAMCALL instruction, which are not emulated in standard virtualized environments like QEMU or GCE. Therefore, this code is impossible to reach during fuzzing.",
  "WorthFuzzing": false
}

null

{
  "PatchDiff": "commit b5039252368fec54798bd273b28f8d111c3ee338\nAuthor: syz-cluster \u003ctriage@syzkaller.com\u003e\nDate:   Tue Aug 4 12:21:12 2026 +0000\n\n    syz-cluster: applied patch under review\n\ndiff --git a/arch/x86/include/asm/tdx_global_metadata.h b/arch/x86/include/asm/tdx_global_metadata.h\nindex 41150d546589c..a86be9e5ec770 100644\n--- a/arch/x86/include/asm/tdx_global_metadata.h\n+++ b/arch/x86/include/asm/tdx_global_metadata.h\n@@ -1,10 +1,15 @@\n /* SPDX-License-Identifier: GPL-2.0 */\n-/* Automatically generated TDX global metadata structures. */\n-#ifndef _X86_VIRT_TDX_AUTO_GENERATED_TDX_GLOBAL_METADATA_H\n-#define _X86_VIRT_TDX_AUTO_GENERATED_TDX_GLOBAL_METADATA_H\n+#ifndef _ASM_X86_TDX_GLOBAL_METADATA_H\n+#define _ASM_X86_TDX_GLOBAL_METADATA_H\n \n #include \u003clinux/types.h\u003e\n \n+/*\n+ * TDX module \"Global Scope Metadata\" as documented in the Intel TDX\n+ * Module ABI spec. Each sub-structure below corresponds to one TDX\n+ * metadata \"Class\"; its members are populated via TDH.SYS.RD SEAMCALLs.\n+ */\n+\n struct tdx_sys_info_version {\n \tu16 minor_version;\n \tu16 major_version;\n@@ -52,4 +57,4 @@ struct tdx_sys_info {\n \tstruct tdx_sys_info_td_conf td_conf;\n };\n \n-#endif\n+#endif /* _ASM_X86_TDX_GLOBAL_METADATA_H */\ndiff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c\nindex 42df8ea464c47..59099cc15f7aa 100644\n--- a/arch/x86/virt/vmx/tdx/tdx.c\n+++ b/arch/x86/virt/vmx/tdx/tdx.c\n@@ -347,7 +347,221 @@ static int read_sys_metadata_field(u64 field_id, u64 *data)\n \treturn 0;\n }\n \n-#include \"tdx_global_metadata.c\"\n+/*\n+ * Mapping between a TDX global metadata field and the C member that\n+ * holds its value. Use TD_SYSINFO_MAP() to populate entries.\n+ */\n+struct tdx_sys_field {\n+\tu64 field_id;\n+\tu16 offset;\n+\tu8  size;\n+};\n+\n+/*\n+ * The size encoded in the field ID and the size of the destination C\n+ * member must agree; BUILD_BUG_ON_ZERO() enforces this at compile time.\n+ */\n+#define TD_SYSINFO_MAP(_field_id, _struct, _member)\t\t\t\t\\\n+\t{\t\t\t\t\t\t\t\t\t\\\n+\t\t.field_id = MD_FIELD_ID_##_field_id,\t\t\t\t\\\n+\t\t.offset   = offsetof(struct _struct, _member),\t\t\t\\\n+\t\t.size     = sizeof_field(struct _struct, _member) +\t\t\\\n+\t\t\t    BUILD_BUG_ON_ZERO(\t\t\t\t\t\\\n+\t\t\t\tsizeof_field(struct _struct, _member) !=\t\\\n+\t\t\t\tMD_FIELD_ID_ELE_SIZE(MD_FIELD_ID_##_field_id)),\t\\\n+\t}\n+\n+/*\n+ * Walk a table of TDX global metadata fields, read each via TDH.SYS.RD,\n+ * and store the result into the matching C member of *@base.\n+ */\n+static int read_sys_metadata_table(const struct tdx_sys_field *fields,\n+\t\t\t\t   int nr_fields, void *base)\n+{\n+\tint i, ret;\n+\tu64 val;\n+\n+\tfor (i = 0; i \u003c nr_fields; i++) {\n+\t\tconst struct tdx_sys_field *f = \u0026fields[i];\n+\n+\t\tret = read_sys_metadata_field(f-\u003efield_id, \u0026val);\n+\t\tif (ret)\n+\t\t\treturn ret;\n+\n+\t\tswitch (f-\u003esize) {\n+\t\tcase 1: *(u8  *)(base + f-\u003eoffset) = val; break;\n+\t\tcase 2: *(u16 *)(base + f-\u003eoffset) = val; break;\n+\t\tcase 4: *(u32 *)(base + f-\u003eoffset) = val; break;\n+\t\tcase 8: *(u64 *)(base + f-\u003eoffset) = val; break;\n+\t\tdefault:\n+\t\t\treturn -EINVAL;\n+\t\t}\n+\t}\n+\treturn 0;\n+}\n+\n+#define MAP_VERSION(_field_id, _member)\t\\\n+\tTD_SYSINFO_MAP(_field_id, tdx_sys_info_version, _member)\n+\n+static const struct tdx_sys_field version_fields[] = {\n+\tMAP_VERSION(MINOR_VERSION,\tminor_version),\n+\tMAP_VERSION(MAJOR_VERSION,\tmajor_version),\n+\tMAP_VERSION(UPDATE_VERSION,\tupdate_version),\n+};\n+\n+static int get_tdx_sys_info_version(struct tdx_sys_info_version *sysinfo_version)\n+{\n+\treturn read_sys_metadata_table(version_fields,\n+\t\t\t\t       ARRAY_SIZE(version_fields),\n+\t\t\t\t       sysinfo_version);\n+}\n+\n+#define MAP_FEATURES(_field_id, _member)\t\\\n+\tTD_SYSINFO_MAP(_field_id, tdx_sys_info_features, _member)\n+\n+static const struct tdx_sys_field features_fields[] __initconst = {\n+\tMAP_FEATURES(TDX_FEATURES0,\ttdx_features0),\n+};\n+\n+static __init int get_tdx_sys_info_features(struct tdx_sys_info_features *sysinfo_features)\n+{\n+\treturn read_sys_metadata_table(features_fields,\n+\t\t\t\t       ARRAY_SIZE(features_fields),\n+\t\t\t\t       sysinfo_features);\n+}\n+\n+#define MAP_TDMR(_field_id, _member)\t\\\n+\tTD_SYSINFO_MAP(_field_id, tdx_sys_info_tdmr, _member)\n+\n+static const struct tdx_sys_field tdmr_fields[] __initconst = {\n+\tMAP_TDMR(MAX_TDMRS,\t\tmax_tdmrs),\n+\tMAP_TDMR(MAX_RESERVED_PER_TDMR,\tmax_reserved_per_tdmr),\n+\tMAP_TDMR(PAMT_4K_ENTRY_SIZE,\tpamt_4k_entry_size),\n+\tMAP_TDMR(PAMT_2M_ENTRY_SIZE,\tpamt_2m_entry_size),\n+\tMAP_TDMR(PAMT_1G_ENTRY_SIZE,\tpamt_1g_entry_size),\n+};\n+\n+static __init int get_tdx_sys_info_tdmr(struct tdx_sys_info_tdmr *sysinfo_tdmr)\n+{\n+\treturn read_sys_metadata_table(tdmr_fields,\n+\t\t\t\t       ARRAY_SIZE(tdmr_fields),\n+\t\t\t\t       sysinfo_tdmr);\n+}\n+\n+#define MAP_TD_CTRL(_field_id, _member)\t\\\n+\tTD_SYSINFO_MAP(_field_id, tdx_sys_info_td_ctrl, _member)\n+\n+static const struct tdx_sys_field td_ctrl_fields[] __initconst = {\n+\tMAP_TD_CTRL(TDR_BASE_SIZE,\ttdr_base_size),\n+\tMAP_TD_CTRL(TDCS_BASE_SIZE,\ttdcs_base_size),\n+\tMAP_TD_CTRL(TDVPS_BASE_SIZE,\ttdvps_base_size),\n+};\n+\n+static __init int get_tdx_sys_info_td_ctrl(struct tdx_sys_info_td_ctrl *sysinfo_td_ctrl)\n+{\n+\treturn read_sys_metadata_table(td_ctrl_fields,\n+\t\t\t\t       ARRAY_SIZE(td_ctrl_fields),\n+\t\t\t\t       sysinfo_td_ctrl);\n+}\n+\n+#define MAP_HANDOFF(_field_id, _member)\t\\\n+\tTD_SYSINFO_MAP(_field_id, tdx_sys_info_handoff, _member)\n+\n+static const struct tdx_sys_field handoff_fields[] = {\n+\tMAP_HANDOFF(MODULE_HV,\tmodule_hv),\n+};\n+\n+static int get_tdx_sys_info_handoff(struct tdx_sys_info_handoff *sysinfo_handoff)\n+{\n+\treturn read_sys_metadata_table(handoff_fields,\n+\t\t\t\t       ARRAY_SIZE(handoff_fields),\n+\t\t\t\t       sysinfo_handoff);\n+}\n+\n+#define MAP_TD_CONF(_field_id, _member)\t\\\n+\tTD_SYSINFO_MAP(_field_id, tdx_sys_info_td_conf, _member)\n+\n+/*\n+ * Scalar fields of the \"TD Configuration\" class.  num_cpuid_config\n+ * must be present here (and must be read before the CPUID arrays\n+ * below) because it sizes them.\n+ */\n+static const struct tdx_sys_field td_conf_fields[] __initconst = {\n+\tMAP_TD_CONF(ATTRIBUTES_FIXED0,\tattributes_fixed0),\n+\tMAP_TD_CONF(ATTRIBUTES_FIXED1,\tattributes_fixed1),\n+\tMAP_TD_CONF(XFAM_FIXED0,\txfam_fixed0),\n+\tMAP_TD_CONF(XFAM_FIXED1,\txfam_fixed1),\n+\tMAP_TD_CONF(NUM_CPUID_CONFIG,\tnum_cpuid_config),\n+\tMAP_TD_CONF(MAX_VCPUS_PER_TD,\tmax_vcpus_per_td),\n+};\n+\n+static __init int get_tdx_sys_info_td_conf(struct tdx_sys_info_td_conf *td_conf)\n+{\n+\tint ret, i, j;\n+\n+\tret = read_sys_metadata_table(td_conf_fields,\n+\t\t\t\t      ARRAY_SIZE(td_conf_fields),\n+\t\t\t\t      td_conf);\n+\tif (ret)\n+\t\treturn ret;\n+\n+\t/*\n+\t * The configurable-CPUID arrays are sized at runtime by\n+\t * num_cpuid_config, so they can't be expressed in a static\n+\t * TD_SYSINFO_MAP table.  Their field IDs are contiguous from\n+\t * the bases announced by the spec.\n+\t */\n+\tif (td_conf-\u003enum_cpuid_config \u003e ARRAY_SIZE(td_conf-\u003ecpuid_config_leaves) ||\n+\t    td_conf-\u003enum_cpuid_config \u003e ARRAY_SIZE(td_conf-\u003ecpuid_config_values))\n+\t\treturn -EINVAL;\n+\n+\tfor (i = 0; i \u003c td_conf-\u003enum_cpuid_config; i++) {\n+\t\tret = read_sys_metadata_field(MD_FIELD_ID_CPUID_CONFIG_LEAVES + i,\n+\t\t\t\t\t      \u0026td_conf-\u003ecpuid_config_leaves[i]);\n+\t\tif (ret)\n+\t\t\treturn ret;\n+\n+\t\tfor (j = 0; j \u003c 2; j++) {\n+\t\t\tu64 fid = MD_FIELD_ID_CPUID_CONFIG_VALUES + i * 2 + j;\n+\n+\t\t\tret = read_sys_metadata_field(fid,\n+\t\t\t\t\t\t      \u0026td_conf-\u003ecpuid_config_values[i][j]);\n+\t\t\tif (ret)\n+\t\t\t\treturn ret;\n+\t\t}\n+\t}\n+\n+\treturn 0;\n+}\n+\n+static __init int get_tdx_sys_info(struct tdx_sys_info *sysinfo)\n+{\n+\tint ret;\n+\n+\tret = get_tdx_sys_info_version(\u0026sysinfo-\u003eversion);\n+\n+\tpr_info(\"Module version: \" TDX_VERSION_FMT \"\\n\",\n+\t\tsysinfo-\u003eversion.major_version,\n+\t\tsysinfo-\u003eversion.minor_version,\n+\t\tsysinfo-\u003eversion.update_version);\n+\n+\tif (ret)\n+\t\treturn ret;\n+\n+\tret = get_tdx_sys_info_features(\u0026sysinfo-\u003efeatures);\n+\tif (ret)\n+\t\treturn ret;\n+\n+\tret = get_tdx_sys_info_tdmr(\u0026sysinfo-\u003etdmr);\n+\tif (ret)\n+\t\treturn ret;\n+\n+\tret = get_tdx_sys_info_td_ctrl(\u0026sysinfo-\u003etd_ctrl);\n+\tif (ret)\n+\t\treturn ret;\n+\n+\treturn get_tdx_sys_info_td_conf(\u0026sysinfo-\u003etd_conf);\n+}\n \n static __init int check_features(struct tdx_sys_info *sysinfo)\n {\ndiff --git a/arch/x86/virt/vmx/tdx/tdx.h b/arch/x86/virt/vmx/tdx/tdx.h\nindex bdfd0e1e337ac..c612b1cf7c142 100644\n--- a/arch/x86/virt/vmx/tdx/tdx.h\n+++ b/arch/x86/virt/vmx/tdx/tdx.h\n@@ -58,6 +58,72 @@\n  */\n #define TDX_VERSION_SHIFT\t\t16\n \n+/*\n+ * Global Scope Metadata field IDs.\n+ *\n+ * See \"Global-Scope (TDX Module) Metadata\" in the Intel TDX Module ABI\n+ * spec.\n+ *\n+ * A field ID is a 64-bit value that encodes the metadata \"Class\"\n+ * (which Linux mirrors in 'struct tdx_sys_info' sub-structures),\n+ * the element size, and a per-class field index. Each ID below\n+ * is paired with the C member that holds its value.\n+ */\n+\n+/* Class \"TDX Module Version\" */\n+#define MD_FIELD_ID_MINOR_VERSION\t\t0x0800000100000003ULL\n+#define MD_FIELD_ID_MAJOR_VERSION\t\t0x0800000100000004ULL\n+#define MD_FIELD_ID_UPDATE_VERSION\t\t0x0800000100000005ULL\n+\n+/* Class \"TDX Features\" */\n+#define MD_FIELD_ID_TDX_FEATURES0\t\t0x0A00000300000008ULL\n+\n+/* Class \"TDMR Info\" */\n+#define MD_FIELD_ID_MAX_TDMRS\t\t\t0x9100000100000008ULL\n+#define MD_FIELD_ID_MAX_RESERVED_PER_TDMR\t0x9100000100000009ULL\n+#define MD_FIELD_ID_PAMT_4K_ENTRY_SIZE\t\t0x9100000100000010ULL\n+#define MD_FIELD_ID_PAMT_2M_ENTRY_SIZE\t\t0x9100000100000011ULL\n+#define MD_FIELD_ID_PAMT_1G_ENTRY_SIZE\t\t0x9100000100000012ULL\n+\n+/* Class \"TD Control Structures\" */\n+#define MD_FIELD_ID_TDR_BASE_SIZE\t\t0x9800000100000000ULL\n+#define MD_FIELD_ID_TDCS_BASE_SIZE\t\t0x9800000100000100ULL\n+#define MD_FIELD_ID_TDVPS_BASE_SIZE\t\t0x9800000100000200ULL\n+\n+/* Class \"TD Configuration\" */\n+#define MD_FIELD_ID_ATTRIBUTES_FIXED0\t\t0x1900000300000000ULL\n+#define MD_FIELD_ID_ATTRIBUTES_FIXED1\t\t0x1900000300000001ULL\n+#define MD_FIELD_ID_XFAM_FIXED0\t\t\t0x1900000300000002ULL\n+#define MD_FIELD_ID_XFAM_FIXED1\t\t\t0x1900000300000003ULL\n+#define MD_FIELD_ID_NUM_CPUID_CONFIG\t\t0x9900000100000004ULL\n+#define MD_FIELD_ID_MAX_VCPUS_PER_TD\t\t0x9900000100000008ULL\n+\n+/* Class \"TDX Module Handoff\" */\n+#define MD_FIELD_ID_MODULE_HV\t\t\t0x8900000100000000ULL\n+\n+/*\n+ * Base IDs for the configurable-CPUID arrays.  The field ID of leaf\n+ * index @i is BASE + i; for the values array, sub-entry @j of index\n+ * @i is BASE + i*2 + j.\n+ */\n+#define MD_FIELD_ID_CPUID_CONFIG_LEAVES\t\t0x9900000300000400ULL\n+#define MD_FIELD_ID_CPUID_CONFIG_VALUES\t\t0x9900000300000500ULL\n+\n+/*\n+ * Sub-field definitions of MD_FIELD_ID.\n+ *\n+ * See \"MD_FIELD_ID (Metadata Field Identifier / Sequence Header)\n+ * Definition\" in the Intel TDX Module ABI spec.\n+ *\n+ *  - Bit 33:32: ELEMENT_SIZE_CODE -- log2 of a single metadata\n+ *                                    element's size in bytes\n+ */\n+#define MD_FIELD_ID_ELE_SIZE_CODE(field_id)\t\\\n+\t(((field_id) \u0026 GENMASK_ULL(33, 32)) \u003e\u003e 32)\n+\n+#define MD_FIELD_ID_ELE_SIZE(field_id)\t\t\\\n+\t(1 \u003c\u003c MD_FIELD_ID_ELE_SIZE_CODE(field_id))\n+\n /* TDX page types */\n #define\tPT_NDA\t\t0x0\n #define\tPT_RSVD\t\t0x1\ndiff --git a/arch/x86/virt/vmx/tdx/tdx_global_metadata.c b/arch/x86/virt/vmx/tdx/tdx_global_metadata.c\ndeleted file mode 100644\nindex e49c300f23d43..0000000000000\n--- a/arch/x86/virt/vmx/tdx/tdx_global_metadata.c\n+++ /dev/null\n@@ -1,133 +0,0 @@\n-// SPDX-License-Identifier: GPL-2.0\n-/*\n- * Automatically generated functions to read TDX global metadata.\n- *\n- * This file doesn't compile on its own as it lacks of inclusion\n- * of SEAMCALL wrapper primitive which reads global metadata.\n- * Include this file to other C file instead.\n- */\n-\n-static int get_tdx_sys_info_version(struct tdx_sys_info_version *sysinfo_version)\n-{\n-\tint ret = 0;\n-\tu64 val;\n-\n-\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x0800000100000003, \u0026val)))\n-\t\tsysinfo_version-\u003eminor_version = val;\n-\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x0800000100000004, \u0026val)))\n-\t\tsysinfo_version-\u003emajor_version = val;\n-\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x0800000100000005, \u0026val)))\n-\t\tsysinfo_version-\u003eupdate_version = val;\n-\n-\treturn ret;\n-}\n-\n-static __init int get_tdx_sys_info_features(struct tdx_sys_info_features *sysinfo_features)\n-{\n-\tint ret = 0;\n-\tu64 val;\n-\n-\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x0A00000300000008, \u0026val)))\n-\t\tsysinfo_features-\u003etdx_features0 = val;\n-\n-\treturn ret;\n-}\n-\n-static __init int get_tdx_sys_info_tdmr(struct tdx_sys_info_tdmr *sysinfo_tdmr)\n-{\n-\tint ret = 0;\n-\tu64 val;\n-\n-\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x9100000100000008, \u0026val)))\n-\t\tsysinfo_tdmr-\u003emax_tdmrs = val;\n-\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x9100000100000009, \u0026val)))\n-\t\tsysinfo_tdmr-\u003emax_reserved_per_tdmr = val;\n-\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x9100000100000010, \u0026val)))\n-\t\tsysinfo_tdmr-\u003epamt_4k_entry_size = val;\n-\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x9100000100000011, \u0026val)))\n-\t\tsysinfo_tdmr-\u003epamt_2m_entry_size = val;\n-\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x9100000100000012, \u0026val)))\n-\t\tsysinfo_tdmr-\u003epamt_1g_entry_size = val;\n-\n-\treturn ret;\n-}\n-\n-static __init int get_tdx_sys_info_td_ctrl(struct tdx_sys_info_td_ctrl *sysinfo_td_ctrl)\n-{\n-\tint ret = 0;\n-\tu64 val;\n-\n-\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x9800000100000000, \u0026val)))\n-\t\tsysinfo_td_ctrl-\u003etdr_base_size = val;\n-\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x9800000100000100, \u0026val)))\n-\t\tsysinfo_td_ctrl-\u003etdcs_base_size = val;\n-\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x9800000100000200, \u0026val)))\n-\t\tsysinfo_td_ctrl-\u003etdvps_base_size = val;\n-\n-\treturn ret;\n-}\n-\n-static __init int get_tdx_sys_info_td_conf(struct tdx_sys_info_td_conf *sysinfo_td_conf)\n-{\n-\tint ret = 0;\n-\tu64 val;\n-\tint i, j;\n-\n-\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x1900000300000000, \u0026val)))\n-\t\tsysinfo_td_conf-\u003eattributes_fixed0 = val;\n-\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x1900000300000001, \u0026val)))\n-\t\tsysinfo_td_conf-\u003eattributes_fixed1 = val;\n-\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x1900000300000002, \u0026val)))\n-\t\tsysinfo_td_conf-\u003exfam_fixed0 = val;\n-\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x1900000300000003, \u0026val)))\n-\t\tsysinfo_td_conf-\u003exfam_fixed1 = val;\n-\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x9900000100000004, \u0026val)))\n-\t\tsysinfo_td_conf-\u003enum_cpuid_config = val;\n-\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x9900000100000008, \u0026val)))\n-\t\tsysinfo_td_conf-\u003emax_vcpus_per_td = val;\n-\tif (sysinfo_td_conf-\u003enum_cpuid_config \u003e ARRAY_SIZE(sysinfo_td_conf-\u003ecpuid_config_leaves))\n-\t\treturn -EINVAL;\n-\tfor (i = 0; i \u003c sysinfo_td_conf-\u003enum_cpuid_config; i++)\n-\t\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x9900000300000400 + i, \u0026val)))\n-\t\t\tsysinfo_td_conf-\u003ecpuid_config_leaves[i] = val;\n-\tif (sysinfo_td_conf-\u003enum_cpuid_config \u003e ARRAY_SIZE(sysinfo_td_conf-\u003ecpuid_config_values))\n-\t\treturn -EINVAL;\n-\tfor (i = 0; i \u003c sysinfo_td_conf-\u003enum_cpuid_config; i++)\n-\t\tfor (j = 0; j \u003c 2; j++)\n-\t\t\tif (!ret \u0026\u0026 !(ret = read_sys_metadata_field(0x9900000300000500 + i * 2 + j, \u0026val)))\n-\t\t\t\tsysinfo_td_conf-\u003ecpuid_config_values[i][j] = val;\n-\n-\treturn ret;\n-}\n-\n-static int get_tdx_sys_info_handoff(struct tdx_sys_info_handoff *sysinfo_handoff)\n-{\n-\tint ret;\n-\tu64 val;\n-\n-\tret = read_sys_metadata_field(0x8900000100000000, \u0026val);\n-\tif (ret)\n-\t\treturn ret;\n-\n-\tsysinfo_handoff-\u003emodule_hv = val;\n-\treturn 0;\n-}\n-\n-static __init int get_tdx_sys_info(struct tdx_sys_info *sysinfo)\n-{\n-\tint ret = 0;\n-\n-\tret = ret ?: get_tdx_sys_info_version(\u0026sysinfo-\u003eversion);\n-\n-\tpr_info(\"Module version: \" TDX_VERSION_FMT \"\\n\",\n-\t\tsysinfo-\u003eversion.major_version,\n-\t\tsysinfo-\u003eversion.minor_version,\n-\t\tsysinfo-\u003eversion.update_version);\n-\n-\tret = ret ?: get_tdx_sys_info_features(\u0026sysinfo-\u003efeatures);\n-\tret = ret ?: get_tdx_sys_info_tdmr(\u0026sysinfo-\u003etdmr);\n-\tret = ret ?: get_tdx_sys_info_td_ctrl(\u0026sysinfo-\u003etd_ctrl);\n-\tret = ret ?: get_tdx_sys_info_td_conf(\u0026sysinfo-\u003etd_conf);\n-\n-\treturn ret;\n-}\n"
}

best-expensive

null

{
  "EnableConfigs": null,
  "FocusSymbols": [],
  "Reasoning": "The patch refactors TDX global metadata reading in the TDX host initialization code (arch/x86/virt/vmx/tdx/tdx.c). This code requires physical Intel TDX hardware, specifically the X86_FEATURE_TDX_HOST_PLATFORM CPU feature and the SEAMCALL instruction, which are not emulated in standard virtualized environments like QEMU or GCE. Therefore, this code is impossible to reach during fuzzing.",
  "WorthFuzzing": false
}

You are an expert Linux kernel maintainer.
Your job is to review a provided patch series and determine
if it makes functional changes to the kernel that should be fuzzed.

IMPORTANT: The changes have ALREADY been applied and committed as the HEAD commit in
your workspace. Do NOT rely on your internal knowledge of the kernel. You must actively
use your code access tools to examine the actual source code and confirm any assumptions.

Return WorthFuzzing=false if the patch only contains:
- Modifications to Documentation/, Kconfig files, or code comments.
- Purely decorative changes, such as logging (e.g., pr_err, printk) or tracepoints.
- Changes to numeric constants or macros that do not functionally alter execution flow.
- Code paths that are impossible to reach in virtualized environments like GCE or QEMU,
  even when utilizing software-emulated hardware (e.g., usb gadget, mac80211_hwsim).
- Code in vendor-specific PCIe switch, SmartNIC, or GPU drivers (e.g., mlxsw, pds_core, qed,
  ionic, amdgpu) that require physical PCIe hardware cards not emulated in standard QEMU.
- Driver .remove, .shutdown, or pci_unregister_driver teardown callbacks (e.g., igb_remove)
  that are executed only during PCI hot-unplug or sysfs driver unbind operations.

If it modifies reachable core kernel logic, drivers, or architectures, use your code search
tools to verify the code can be executed, then return WorthFuzzing=true.

When returning WorthFuzzing=true, you MUST ALSO:
1. Extract any specific kernel functions that should be heavily fuzzed into FocusSymbols.
   Avoid listing generic hot-path functions to prevent skewed test distributions.
   Prefer non-static, non-inlined API entrypoint functions over internal static helper functions
   (which are inlined by the compiler and do not have distinct symbol addresses).
2. Identify any specific CONFIG_ options required to properly test this new/modified feature.
   Go and look into the Kconfig files and check for ifdefs around the code, do not make assumptions.
   Also check "depends on" lines in Kconfig to include any non-standard parent subsystem configs
   needed for Kbuild to compile the code statically into vmlinux. List them in the EnableConfigs
   output array, and DO NOT add a 'CONFIG_' prefix (e.g., return "NET_IPV4" instead of "CONFIG_NET_IPV4").
Prefer calling several tools at the same time to save round-trips.


Use set-results tool to provide results of the analysis.
It must be called exactly once before the final reply.
Ignore results of this tool.

For your convenience, here is the diff of the changes:
commit b5039252368fec54798bd273b28f8d111c3ee338
Author: syz-cluster <triage@syzkaller.com>
Date:   Tue Aug 4 12:21:12 2026 +0000

    syz-cluster: applied patch under review

diff --git a/arch/x86/include/asm/tdx_global_metadata.h b/arch/x86/include/asm/tdx_global_metadata.h
index 41150d546589c..a86be9e5ec770 100644
--- a/arch/x86/include/asm/tdx_global_metadata.h
+++ b/arch/x86/include/asm/tdx_global_metadata.h
@@ -1,10 +1,15 @@
 /* SPDX-License-Identifier: GPL-2.0 */
-/* Automatically generated TDX global metadata structures. */
-#ifndef _X86_VIRT_TDX_AUTO_GENERATED_TDX_GLOBAL_METADATA_H
-#define _X86_VIRT_TDX_AUTO_GENERATED_TDX_GLOBAL_METADATA_H
+#ifndef _ASM_X86_TDX_GLOBAL_METADATA_H
+#define _ASM_X86_TDX_GLOBAL_METADATA_H
 
 #include <linux/types.h>
 
+/*
+ * TDX module "Global Scope Metadata" as documented in the Intel TDX
+ * Module ABI spec. Each sub-structure below corresponds to one TDX
+ * metadata "Class"; its members are populated via TDH.SYS.RD SEAMCALLs.
+ */
+
 struct tdx_sys_info_version {
 	u16 minor_version;
 	u16 major_version;
@@ -52,4 +57,4 @@ struct tdx_sys_info {
 	struct tdx_sys_info_td_conf td_conf;
 };
 
-#endif
+#endif /* _ASM_X86_TDX_GLOBAL_METADATA_H */
diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
index 42df8ea464c47..59099cc15f7aa 100644
--- a/arch/x86/virt/vmx/tdx/tdx.c
+++ b/arch/x86/virt/vmx/tdx/tdx.c
@@ -347,7 +347,221 @@ static int read_sys_metadata_field(u64 field_id, u64 *data)
 	return 0;
 }
 
-#include "tdx_global_metadata.c"
+/*
+ * Mapping between a TDX global metadata field and the C member that
+ * holds its value. Use TD_SYSINFO_MAP() to populate entries.
+ */
+struct tdx_sys_field {
+	u64 field_id;
+	u16 offset;
+	u8  size;
+};
+
+/*
+ * The size encoded in the field ID and the size of the destination C
+ * member must agree; BUILD_BUG_ON_ZERO() enforces this at compile time.
+ */
+#define TD_SYSINFO_MAP(_field_id, _struct, _member)				\
+	{									\
+		.field_id = MD_FIELD_ID_##_field_id,				\
+		.offset   = offsetof(struct _struct, _member),			\
+		.size     = sizeof_field(struct _struct, _member) +		\
+			    BUILD_BUG_ON_ZERO(					\
+				sizeof_field(struct _struct, _member) !=	\
+				MD_FIELD_ID_ELE_SIZE(MD_FIELD_ID_##_field_id)),	\
+	}
+
+/*
+ * Walk a table of TDX global metadata fields, read each via TDH.SYS.RD,
+ * and store the result into the matching C member of *@base.
+ */
+static int read_sys_metadata_table(const struct tdx_sys_field *fields,
+				   int nr_fields, void *base)
+{
+	int i, ret;
+	u64 val;
+
+	for (i = 0; i < nr_fields; i++) {
+		const struct tdx_sys_field *f = &fields[i];
+
+		ret = read_sys_metadata_field(f->field_id, &val);
+		if (ret)
+			return ret;
+
+		switch (f->size) {
+		case 1: *(u8  *)(base + f->offset) = val; break;
+		case 2: *(u16 *)(base + f->offset) = val; break;
+		case 4: *(u32 *)(base + f->offset) = val; break;
+		case 8: *(u64 *)(base + f->offset) = val; break;
+		default:
+			return -EINVAL;
+		}
+	}
+	return 0;
+}
+
+#define MAP_VERSION(_field_id, _member)	\
+	TD_SYSINFO_MAP(_field_id, tdx_sys_info_version, _member)
+
+static const struct tdx_sys_field version_fields[] = {
+	MAP_VERSION(MINOR_VERSION,	minor_version),
+	MAP_VERSION(MAJOR_VERSION,	major_version),
+	MAP_VERSION(UPDATE_VERSION,	update_version),
+};
+
+static int get_tdx_sys_info_version(struct tdx_sys_info_version *sysinfo_version)
+{
+	return read_sys_metadata_table(version_fields,
+				       ARRAY_SIZE(version_fields),
+				       sysinfo_version);
+}
+
+#define MAP_FEATURES(_field_id, _member)	\
+	TD_SYSINFO_MAP(_field_id, tdx_sys_info_features, _member)
+
+static const struct tdx_sys_field features_fields[] __initconst = {
+	MAP_FEATURES(TDX_FEATURES0,	tdx_features0),
+};
+
+static __init int get_tdx_sys_info_features(struct tdx_sys_info_features *sysinfo_features)
+{
+	return read_sys_metadata_table(features_fields,
+				       ARRAY_SIZE(features_fields),
+				       sysinfo_features);
+}
+
+#define MAP_TDMR(_field_id, _member)	\
+	TD_SYSINFO_MAP(_field_id, tdx_sys_info_tdmr, _member)
+
+static const struct tdx_sys_field tdmr_fields[] __initconst = {
+	MAP_TDMR(MAX_TDMRS,		max_tdmrs),
+	MAP_TDMR(MAX_RESERVED_PER_TDMR,	max_reserved_per_tdmr),
+	MAP_TDMR(PAMT_4K_ENTRY_SIZE,	pamt_4k_entry_size),
+	MAP_TDMR(PAMT_2M_ENTRY_SIZE,	pamt_2m_entry_size),
+	MAP_TDMR(PAMT_1G_ENTRY_SIZE,	pamt_1g_entry_size),
+};
+
+static __init int get_tdx_sys_info_tdmr(struct tdx_sys_info_tdmr *sysinfo_tdmr)
+{
+	return read_sys_metadata_table(tdmr_fields,
+				       ARRAY_SIZE(tdmr_fields),
+				       sysinfo_tdmr);
+}
+
+#define MAP_TD_CTRL(_field_id, _member)	\
+	TD_SYSINFO_MAP(_field_id, tdx_sys_info_td_ctrl, _member)
+
+static const struct tdx_sys_field td_ctrl_fields[] __initconst = {
+	MAP_TD_CTRL(TDR_BASE_SIZE,	tdr_base_size),
+	MAP_TD_CTRL(TDCS_BASE_SIZE,	tdcs_base_size),
+	MAP_TD_CTRL(TDVPS_BASE_SIZE,	tdvps_base_size),
+};
+
+static __init int get_tdx_sys_info_td_ctrl(struct tdx_sys_info_td_ctrl *sysinfo_td_ctrl)
+{
+	return read_sys_metadata_table(td_ctrl_fields,
+				       ARRAY_SIZE(td_ctrl_fields),
+				       sysinfo_td_ctrl);
+}
+
+#define MAP_HANDOFF(_field_id, _member)	\
+	TD_SYSINFO_MAP(_field_id, tdx_sys_info_handoff, _member)
+
+static const struct tdx_sys_field handoff_fields[] = {
+	MAP_HANDOFF(MODULE_HV,	module_hv),
+};
+
+static int get_tdx_sys_info_handoff(struct tdx_sys_info_handoff *sysinfo_handoff)
+{
+	return read_sys_metadata_table(handoff_fields,
+				       ARRAY_SIZE(handoff_fields),
+				       sysinfo_handoff);
+}
+
+#define MAP_TD_CONF(_field_id, _member)	\
+	TD_SYSINFO_MAP(_field_id, tdx_sys_info_td_conf, _member)
+
+/*
+ * Scalar fields of the "TD Configuration" class.  num_cpuid_config
+ * must be present here (and must be read before the CPUID arrays
+ * below) because it sizes them.
+ */
+static const struct tdx_sys_field td_conf_fields[] __initconst = {
+	MAP_TD_CONF(ATTRIBUTES_FIXED0,	attributes_fixed0),
+	MAP_TD_CONF(ATTRIBUTES_FIXED1,	attributes_fixed1),
+	MAP_TD_CONF(XFAM_FIXED0,	xfam_fixed0),
+	MAP_TD_CONF(XFAM_FIXED1,	xfam_fixed1),
+	MAP_TD_CONF(NUM_CPUID_CONFIG,	num_cpuid_config),
+	MAP_TD_CONF(MAX_VCPUS_PER_TD,	max_vcpus_per_td),
+};
+
+static __init int get_tdx_sys_info_td_conf(struct tdx_sys_info_td_conf *td_conf)
+{
+	int ret, i, j;
+
+	ret = read_sys_metadata_table(td_conf_fields,
+				      ARRAY_SIZE(td_conf_fields),
+				      td_conf);
+	if (ret)
+		return ret;
+
+	/*
+	 * The configurable-CPUID arrays are sized at runtime by
+	 * num_cpuid_config, so they can't be expressed in a static
+	 * TD_SYSINFO_MAP table.  Their field IDs are contiguous from
+	 * the bases announced by the spec.
+	 */
+	if (td_conf->num_cpuid_config > ARRAY_SIZE(td_conf->cpuid_config_leaves) ||
+	    td_conf->num_cpuid_config > ARRAY_SIZE(td_conf->cpuid_config_values))
+		return -EINVAL;
+
+	for (i = 0; i < td_conf->num_cpuid_config; i++) {
+		ret = read_sys_metadata_field(MD_FIELD_ID_CPUID_CONFIG_LEAVES + i,
+					      &td_conf->cpuid_config_leaves[i]);
+		if (ret)
+			return ret;
+
+		for (j = 0; j < 2; j++) {
+			u64 fid = MD_FIELD_ID_CPUID_CONFIG_VALUES + i * 2 + j;
+
+			ret = read_sys_metadata_field(fid,
+						      &td_conf->cpuid_config_values[i][j]);
+			if (ret)
+				return ret;
+		}
+	}
+
+	return 0;
+}
+
+static __init int get_tdx_sys_info(struct tdx_sys_info *sysinfo)
+{
+	int ret;
+
+	ret = get_tdx_sys_info_version(&sysinfo->version);
+
+	pr_info("Module version: " TDX_VERSION_FMT "\n",
+		sysinfo->version.major_version,
+		sysinfo->version.minor_version,
+		sysinfo->version.update_version);
+
+	if (ret)
+		return ret;
+
+	ret = get_tdx_sys_info_features(&sysinfo->features);
+	if (ret)
+		return ret;
+
+	ret = get_tdx_sys_info_tdmr(&sysinfo->tdmr);
+	if (ret)
+		return ret;
+
+	ret = get_tdx_sys_info_td_ctrl(&sysinfo->td_ctrl);
+	if (ret)
+		return ret;
+
+	return get_tdx_sys_info_td_conf(&sysinfo->td_conf);
+}
 
 static __init int check_features(struct tdx_sys_info *sysinfo)
 {
diff --git a/arch/x86/virt/vmx/tdx/tdx.h b/arch/x86/virt/vmx/tdx/tdx.h
index bdfd0e1e337ac..c612b1cf7c142 100644
--- a/arch/x86/virt/vmx/tdx/tdx.h
+++ b/arch/x86/virt/vmx/tdx/tdx.h
@@ -58,6 +58,72 @@
  */
 #define TDX_VERSION_SHIFT		16
 
+/*
+ * Global Scope Metadata field IDs.
+ *
+ * See "Global-Scope (TDX Module) Metadata" in the Intel TDX Module ABI
+ * spec.
+ *
+ * A field ID is a 64-bit value that encodes the metadata "Class"
+ * (which Linux mirrors in 'struct tdx_sys_info' sub-structures),
+ * the element size, and a per-class field index. Each ID below
+ * is paired with the C member that holds its value.
+ */
+
+/* Class "TDX Module Version" */
+#define MD_FIELD_ID_MINOR_VERSION		0x0800000100000003ULL
+#define MD_FIELD_ID_MAJOR_VERSION		0x0800000100000004ULL
+#define MD_FIELD_ID_UPDATE_VERSION		0x0800000100000005ULL
+
+/* Class "TDX Features" */
+#define MD_FIELD_ID_TDX_FEATURES0		0x0A00000300000008ULL
+
+/* Class "TDMR Info" */
+#define MD_FIELD_ID_MAX_TDMRS			0x9100000100000008ULL
+#define MD_FIELD_ID_MAX_RESERVED_PER_TDMR	0x9100000100000009ULL
+#define MD_FIELD_ID_PAMT_4K_ENTRY_SIZE		0x9100000100000010ULL
+#define MD_FIELD_ID_PAMT_2M_ENTRY_SIZE		0x9100000100000011ULL
+#define MD_FIELD_ID_PAMT_1G_ENTRY_SIZE		0x9100000100000012ULL
+
+/* Class "TD Control Structures" */
+#define MD_FIELD_ID_TDR_BASE_SIZE		0x9800000100000000ULL
+#define MD_FIELD_ID_TDCS_BASE_SIZE		0x9800000100000100ULL
+#define MD_FIELD_ID_TDVPS_BASE_SIZE		0x9800000100000200ULL
+
+/* Class "TD Configuration" */
+#define MD_FIELD_ID_ATTRIBUTES_FIXED0		0x1900000300000000ULL
+#define MD_FIELD_ID_ATTRIBUTES_FIXED1		0x1900000300000001ULL
+#define MD_FIELD_ID_XFAM_FIXED0			0x1900000300000002ULL
+#define MD_FIELD_ID_XFAM_FIXED1			0x1900000300000003ULL
+#define MD_FIELD_ID_NUM_CPUID_CONFIG		0x9900000100000004ULL
+#define MD_FIELD_ID_MAX_VCPUS_PER_TD		0x9900000100000008ULL
+
+/* Class "TDX Module Handoff" */
+#define MD_FIELD_ID_MODULE_HV			0x8900000100000000ULL
+
+/*
+ * Base IDs for the configurable-CPUID arrays.  The field ID of leaf
+ * index @i is BASE + i; for the values array, sub-entry @j of index
+ * @i is BASE + i*2 + j.
+ */
+#define MD_FIELD_ID_CPUID_CONFIG_LEAVES		0x9900000300000400ULL
+#define MD_FIELD_ID_CPUID_CONFIG_VALUES		0x9900000300000500ULL
+
+/*
+ * Sub-field definitions of MD_FIELD_ID.
+ *
+ * See "MD_FIELD_ID (Metadata Field Identifier / Sequence Header)
+ * Definition" in the Intel TDX Module ABI spec.
+ *
+ *  - Bit 33:32: ELEMENT_SIZE_CODE -- log2 of a single metadata
+ *                                    element's size in bytes
+ */
+#define MD_FIELD_ID_ELE_SIZE_CODE(field_id)	\
+	(((field_id) & GENMASK_ULL(33, 32)) >> 32)
+
+#define MD_FIELD_ID_ELE_SIZE(field_id)		\
+	(1 << MD_FIELD_ID_ELE_SIZE_CODE(field_id))
+
 /* TDX page types */
 #define	PT_NDA		0x0
 #define	PT_RSVD		0x1
diff --git a/arch/x86/virt/vmx/tdx/tdx_global_metadata.c b/arch/x86/virt/vmx/tdx/tdx_global_metadata.c
deleted file mode 100644
index e49c300f23d43..0000000000000
--- a/arch/x86/virt/vmx/tdx/tdx_global_metadata.c
+++ /dev/null
@@ -1,133 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Automatically generated functions to read TDX global metadata.
- *
- * This file doesn't compile on its own as it lacks of inclusion
- * of SEAMCALL wrapper primitive which reads global metadata.
- * Include this file to other C file instead.
- */
-
-static int get_tdx_sys_info_version(struct tdx_sys_info_version *sysinfo_version)
-{
-	int ret = 0;
-	u64 val;
-
-	if (!ret && !(ret = read_sys_metadata_field(0x0800000100000003, &val)))
-		sysinfo_version->minor_version = val;
-	if (!ret && !(ret = read_sys_metadata_field(0x0800000100000004, &val)))
-		sysinfo_version->major_version = val;
-	if (!ret && !(ret = read_sys_metadata_field(0x0800000100000005, &val)))
-		sysinfo_version->update_version = val;
-
-	return ret;
-}
-
-static __init int get_tdx_sys_info_features(struct tdx_sys_info_features *sysinfo_features)
-{
-	int ret = 0;
-	u64 val;
-
-	if (!ret && !(ret = read_sys_metadata_field(0x0A00000300000008, &val)))
-		sysinfo_features->tdx_features0 = val;
-
-	return ret;
-}
-
-static __init int get_tdx_sys_info_tdmr(struct tdx_sys_info_tdmr *sysinfo_tdmr)
-{
-	int ret = 0;
-	u64 val;
-
-	if (!ret && !(ret = read_sys_metadata_field(0x9100000100000008, &val)))
-		sysinfo_tdmr->max_tdmrs = val;
-	if (!ret && !(ret = read_sys_metadata_field(0x9100000100000009, &val)))
-		sysinfo_tdmr->max_reserved_per_tdmr = val;
-	if (!ret && !(ret = read_sys_metadata_field(0x9100000100000010, &val)))
-		sysinfo_tdmr->pamt_4k_entry_size = val;
-	if (!ret && !(ret = read_sys_metadata_field(0x9100000100000011, &val)))
-		sysinfo_tdmr->pamt_2m_entry_size = val;
-	if (!ret && !(ret = read_sys_metadata_field(0x9100000100000012, &val)))
-		sysinfo_tdmr->pamt_1g_entry_size = val;
-
-	return ret;
-}
-
-static __init int get_tdx_sys_info_td_ctrl(struct tdx_sys_info_td_ctrl *sysinfo_td_ctrl)
-{
-	int ret = 0;
-	u64 val;
-
-	if (!ret && !(ret = read_sys_metadata_field(0x9800000100000000, &val)))
-		sysinfo_td_ctrl->tdr_base_size = val;
-	if (!ret && !(ret = read_sys_metadata_field(0x9800000100000100, &val)))
-		sysinfo_td_ctrl->tdcs_base_size = val;
-	if (!ret && !(ret = read_sys_metadata_field(0x9800000100000200, &val)))
-		sysinfo_td_ctrl->tdvps_base_size = val;
-
-	return ret;
-}
-
-static __init int get_tdx_sys_info_td_conf(struct tdx_sys_info_td_conf *sysinfo_td_conf)
-{
-	int ret = 0;
-	u64 val;
-	int i, j;
-
-	if (!ret && !(ret = read_sys_metadata_field(0x1900000300000000, &val)))
-		sysinfo_td_conf->attributes_fixed0 = val;
-	if (!ret && !(ret = read_sys_metadata_field(0x1900000300000001, &val)))
-		sysinfo_td_conf->attributes_fixed1 = val;
-	if (!ret && !(ret = read_sys_metadata_field(0x1900000300000002, &val)))
-		sysinfo_td_conf->xfam_fixed0 = val;
-	if (!ret && !(ret = read_sys_metadata_field(0x1900000300000003, &val)))
-		sysinfo_td_conf->xfam_fixed1 = val;
-	if (!ret && !(ret = read_sys_metadata_field(0x9900000100000004, &val)))
-		sysinfo_td_conf->num_cpuid_config = val;
-	if (!ret && !(ret = read_sys_metadata_field(0x9900000100000008, &val)))
-		sysinfo_td_conf->max_vcpus_per_td = val;
-	if (sysinfo_td_conf->num_cpuid_config > ARRAY_SIZE(sysinfo_td_conf->cpuid_config_leaves))
-		return -EINVAL;
-	for (i = 0; i < sysinfo_td_conf->num_cpuid_config; i++)
-		if (!ret && !(ret = read_sys_metadata_field(0x9900000300000400 + i, &val)))
-			sysinfo_td_conf->cpuid_config_leaves[i] = val;
-	if (sysinfo_td_conf->num_cpuid_config > ARRAY_SIZE(sysinfo_td_conf->cpuid_config_values))
-		return -EINVAL;
-	for (i = 0; i < sysinfo_td_conf->num_cpuid_config; i++)
-		for (j = 0; j < 2; j++)
-			if (!ret && !(ret = read_sys_metadata_field(0x9900000300000500 + i * 2 + j, &val)))
-				sysinfo_td_conf->cpuid_config_values[i][j] = val;
-
-	return ret;
-}
-
-static int get_tdx_sys_info_handoff(struct tdx_sys_info_handoff *sysinfo_handoff)
-{
-	int ret;
-	u64 val;
-
-	ret = read_sys_metadata_field(0x8900000100000000, &val);
-	if (ret)
-		return ret;
-
-	sysinfo_handoff->module_hv = val;
-	return 0;
-}
-
-static __init int get_tdx_sys_info(struct tdx_sys_info *sysinfo)
-{
-	int ret = 0;
-
-	ret = ret ?: get_tdx_sys_info_version(&sysinfo->version);
-
-	pr_info("Module version: " TDX_VERSION_FMT "\n",
-		sysinfo->version.major_version,
-		sysinfo->version.minor_version,
-		sysinfo->version.update_version);
-
-	ret = ret ?: get_tdx_sys_info_features(&sysinfo->features);
-	ret = ret ?: get_tdx_sys_info_tdmr(&sysinfo->tdmr);
-	ret = ret ?: get_tdx_sys_info_td_ctrl(&sysinfo->td_ctrl);
-	ret = ret ?: get_tdx_sys_info_td_conf(&sysinfo->td_conf);
-
-	return ret;
-}

gemini-3.1-pro-preview

null

null

							input: 8765
							output: 42
							thoughts: 270
						

**Analyzing the TDX Metadata Patch**

Okay, so I'm looking at this patch that refactors the TDX global metadata reading logic. It seems they're ditching the auto-generated `tdx_global_metadata.c` in favor of a table-driven approach using `TD_SYSINFO_MAP` and `read_sys_metadata_table`. This is a pretty significant change, essentially a refactoring of the TDX initialization code. My immediate thought is, "is this even *reachable* in a typical virtualized environment?" TDX, after all, hinges on specific Intel TDX hardware. And I need to clarify, are we talking TDX guest or host here?

Wait, the path, `arch/x86/virt/vmx/tdx/tdx.c`, that's the TDX host support code, right? It's the KVM/TDX module initialization. Okay, so now the question becomes, can this be fuzzed or tested in a standard QEMU or GCE environment? I'm betting no, because TDX host support fundamentally requires that TDX hardware to be present. That's a huge hurdle.

Now, let's explore if this is possible without hardware. I know that TDX host initialization usually checks for the hardware support early on and bails out if it's not detected. I need to dig into `arch/x86/virt/vmx/tdx/tdx.c` to confirm that's happening. I need to determine how robust this check is, and what happens if it's bypassed somehow, deliberately or accidentally. I'm going to look for any logic that might allow execution to continue even without the expected hardware, or any vulnerabilities in the hardware checks.

{
  "Expression": "tdx_init",
  "PathPrefix": "arch/x86/virt/vmx/tdx/tdx.c"
}

{
  "Output": "arch/x86/virt/vmx/tdx/tdx.c=1718=static void __init check_tdx_erratum(void)\n--\narch/x86/virt/vmx/tdx/tdx.c-1742-\narch/x86/virt/vmx/tdx/tdx.c:1743:void __init tdx_init(void)\narch/x86/virt/vmx/tdx/tdx.c-1744-{\n"
}

gemini-3.1-pro-preview

null

null

							input: 9591
							output: 47
							thoughts: 13
						

Here's my attempt at summarizing the thought process, tailored for an expert audience:

**Diving into `tdx_init`**

Alright, let's get down to brass tacks. I need to understand what `tdx_init` is actually *doing*. I'm immediately interested in the initialization process for this particular module or subsystem. What's the context? What are the dependencies? Is this a standard initialization pattern or something custom-built? I need to quickly identify the key tasks `tdx_init` is responsible for, the resources it manages, and any external interactions it triggers. I'm going to want to check for error handling too. Knowing where the initialization is occurring will help me. I should be able to quickly grasp the implications for the overall system behavior. This will likely involve looking at the functions this function calls as well. Time to start digging!

{
  "File": "arch/x86/virt/vmx/tdx/tdx.c",
  "FirstLine": 1743,
  "LineCount": 50
}

{
  "Contents": "1743:\tvoid __init tdx_init(void)\n1744:\t{\n1745:\t\tu32 tdx_keyid_start, nr_tdx_keyids;\n1746:\t\tint err;\n1747:\t\n1748:\t\terr = record_keyid_partitioning(\u0026tdx_keyid_start, \u0026nr_tdx_keyids);\n1749:\t\tif (err)\n1750:\t\t\treturn;\n1751:\t\n1752:\t\tpr_info(\"BIOS enabled: private KeyID range [%u, %u)\\n\",\n1753:\t\t\t\ttdx_keyid_start, tdx_keyid_start + nr_tdx_keyids);\n1754:\t\n1755:\t\t/*\n1756:\t\t * The TDX module itself requires one 'global KeyID' to protect\n1757:\t\t * its metadata.  If there's only one TDX KeyID, there won't be\n1758:\t\t * any left for TDX guests thus there's no point to enable TDX\n1759:\t\t * at all.\n1760:\t\t */\n1761:\t\tif (nr_tdx_keyids \u003c 2) {\n1762:\t\t\tpr_err(\"initialization failed: too few private KeyIDs available.\\n\");\n1763:\t\t\treturn;\n1764:\t\t}\n1765:\t\n1766:\t\t/*\n1767:\t\t * At this point, hibernation_available() indicates whether or\n1768:\t\t * not hibernation support has been permanently disabled.\n1769:\t\t */\n1770:\t\tif (hibernation_available()) {\n1771:\t\t\tpr_err(\"initialization failed: Hibernation support is enabled\\n\");\n1772:\t\t\treturn;\n1773:\t\t}\n1774:\t\n1775:\t\terr = register_memory_notifier(\u0026tdx_memory_nb);\n1776:\t\tif (err) {\n1777:\t\t\tpr_err(\"initialization failed: register_memory_notifier() failed (%d)\\n\",\n1778:\t\t\t\t\terr);\n1779:\t\t\treturn;\n1780:\t\t}\n1781:\t\n1782:\t#if defined(CONFIG_ACPI) \u0026\u0026 defined(CONFIG_SUSPEND)\n1783:\t\tpr_info(\"Disable ACPI S3. Turn off TDX in the BIOS to use ACPI S3.\\n\");\n1784:\t\tacpi_suspend_lowlevel = NULL;\n1785:\t#endif\n1786:\t\n1787:\t\t/*\n1788:\t\t * Just use the first TDX KeyID as the 'global KeyID' and\n1789:\t\t * leave the rest for TDX guests.\n1790:\t\t */\n1791:\t\ttdx_global_keyid = tdx_keyid_start;\n1792:\t\ttdx_guest_keyid_start = tdx_keyid_start + 1;\n"
}

gemini-3.1-pro-preview

null

null

							input: 10617
							output: 46
							thoughts: 28
						

Here's my thought process, as if I were considering this myself:

**Tracing the TDX Initialization**

Okay, so `tdx_init`... that's a key function in the TDX (Trust Domain Extensions) setup, and it's being invoked early, during the boot process. That makes sense, establishes the secure environment foundation. But now I need to follow the data and control flow more carefully. The real question is: where is the information that `tdx_init` depends on coming from? Specifically, I need to know where `get_tdx_sys_info` is being called from. Is it called early as well, or is it getting information later on? Knowing the call sites for that function will tell me how the relevant system information is being acquired and used in the TDX lifecycle. This trace is important for understanding the security context.

{
  "Expression": "get_tdx_sys_info",
  "PathPrefix": "arch/x86/virt/vmx/tdx/tdx.c"
}

{
  "Output": "arch/x86/virt/vmx/tdx/tdx.c=406=static const struct tdx_sys_field version_fields[] = {\n--\narch/x86/virt/vmx/tdx/tdx.c-411-\narch/x86/virt/vmx/tdx/tdx.c:412:static int get_tdx_sys_info_version(struct tdx_sys_info_version *sysinfo_version)\narch/x86/virt/vmx/tdx/tdx.c-413-{\n--\narch/x86/virt/vmx/tdx/tdx.c=422=static const struct tdx_sys_field features_fields[] __initconst = {\n--\narch/x86/virt/vmx/tdx/tdx.c-425-\narch/x86/virt/vmx/tdx/tdx.c:426:static __init int get_tdx_sys_info_features(struct tdx_sys_info_features *sysinfo_features)\narch/x86/virt/vmx/tdx/tdx.c-427-{\n--\narch/x86/virt/vmx/tdx/tdx.c=436=static const struct tdx_sys_field tdmr_fields[] __initconst = {\n--\narch/x86/virt/vmx/tdx/tdx.c-443-\narch/x86/virt/vmx/tdx/tdx.c:444:static __init int get_tdx_sys_info_tdmr(struct tdx_sys_info_tdmr *sysinfo_tdmr)\narch/x86/virt/vmx/tdx/tdx.c-445-{\n--\narch/x86/virt/vmx/tdx/tdx.c=454=static const struct tdx_sys_field td_ctrl_fields[] __initconst = {\n--\narch/x86/virt/vmx/tdx/tdx.c-459-\narch/x86/virt/vmx/tdx/tdx.c:460:static __init int get_tdx_sys_info_td_ctrl(struct tdx_sys_info_td_ctrl *sysinfo_td_ctrl)\narch/x86/virt/vmx/tdx/tdx.c-461-{\n--\narch/x86/virt/vmx/tdx/tdx.c=470=static const struct tdx_sys_field handoff_fields[] = {\n--\narch/x86/virt/vmx/tdx/tdx.c-473-\narch/x86/virt/vmx/tdx/tdx.c:474:static int get_tdx_sys_info_handoff(struct tdx_sys_info_handoff *sysinfo_handoff)\narch/x86/virt/vmx/tdx/tdx.c-475-{\n--\narch/x86/virt/vmx/tdx/tdx.c=489=static const struct tdx_sys_field td_conf_fields[] __initconst = {\n--\narch/x86/virt/vmx/tdx/tdx.c-497-\narch/x86/virt/vmx/tdx/tdx.c:498:static __init int get_tdx_sys_info_td_conf(struct tdx_sys_info_td_conf *td_conf)\narch/x86/virt/vmx/tdx/tdx.c-499-{\n--\narch/x86/virt/vmx/tdx/tdx.c-536-\narch/x86/virt/vmx/tdx/tdx.c:537:static __init int get_tdx_sys_info(struct tdx_sys_info *sysinfo)\narch/x86/virt/vmx/tdx/tdx.c-538-{\n--\narch/x86/virt/vmx/tdx/tdx.c-540-\narch/x86/virt/vmx/tdx/tdx.c:541:\tret = get_tdx_sys_info_version(\u0026sysinfo-\u003eversion);\narch/x86/virt/vmx/tdx/tdx.c-542-\n--\narch/x86/virt/vmx/tdx/tdx.c-550-\narch/x86/virt/vmx/tdx/tdx.c:551:\tret = get_tdx_sys_info_features(\u0026sysinfo-\u003efeatures);\narch/x86/virt/vmx/tdx/tdx.c-552-\tif (ret)\n--\narch/x86/virt/vmx/tdx/tdx.c-554-\narch/x86/virt/vmx/tdx/tdx.c:555:\tret = get_tdx_sys_info_tdmr(\u0026sysinfo-\u003etdmr);\narch/x86/virt/vmx/tdx/tdx.c-556-\tif (ret)\n--\narch/x86/virt/vmx/tdx/tdx.c-558-\narch/x86/virt/vmx/tdx/tdx.c:559:\tret = get_tdx_sys_info_td_ctrl(\u0026sysinfo-\u003etd_ctrl);\narch/x86/virt/vmx/tdx/tdx.c-560-\tif (ret)\n--\narch/x86/virt/vmx/tdx/tdx.c-562-\narch/x86/virt/vmx/tdx/tdx.c:563:\treturn get_tdx_sys_info_td_conf(\u0026sysinfo-\u003etd_conf);\narch/x86/virt/vmx/tdx/tdx.c-564-}\n--\narch/x86/virt/vmx/tdx/tdx.c=1359=static __init int init_tdx_module(void)\n--\narch/x86/virt/vmx/tdx/tdx.c-1362-\narch/x86/virt/vmx/tdx/tdx.c:1363:\tret = get_tdx_sys_info(\u0026tdx_sysinfo);\narch/x86/virt/vmx/tdx/tdx.c-1364-\tif (ret)\n--\narch/x86/virt/vmx/tdx/tdx.c=1485=int tdx_module_shutdown(void)\n--\narch/x86/virt/vmx/tdx/tdx.c-1491-\narch/x86/virt/vmx/tdx/tdx.c:1492:\tret = get_tdx_sys_info_handoff(\u0026handoff);\narch/x86/virt/vmx/tdx/tdx.c-1493-\t/*\n--\narch/x86/virt/vmx/tdx/tdx.c=1523=int tdx_module_run_update(void)\n--\narch/x86/virt/vmx/tdx/tdx.c-1531-\narch/x86/virt/vmx/tdx/tdx.c:1532:\tret = get_tdx_sys_info_version(\u0026tdx_sysinfo.version);\narch/x86/virt/vmx/tdx/tdx.c-1533-\t/*\n"
}

gemini-3.1-pro-preview

null

null

							input: 12785
							output: 44
							thoughts: 32
						

Okay, here's my interpretation of that thought process, from an expert's perspective:

**Investigating TDX Module Initialization**

Alright, so I see `init_tdx_module` is calling `get_tdx_sys_info`. That's standard practice, initializing the Trusted Domain Extensions (TDX) module usually involves gathering some system-level information. My immediate question, though, is where exactly is `init_tdx_module` being invoked? Understanding the call stack around the initialization routine is critical. Is it being triggered at boot, on-demand by another service, or in response to some external event? Knowing the calling context gives a huge amount of insight into its purpose and potential failure modes. I need to trace back from that call to understand the module's integration into the overall system architecture. Context is key here.

{
  "Expression": "init_tdx_module",
  "PathPrefix": "arch/x86/virt/vmx/tdx/tdx.c"
}

{
  "Output": "arch/x86/virt/vmx/tdx/tdx.c=1340=static __init int init_tdmrs(struct tdmr_info_list *tdmr_list)\n--\narch/x86/virt/vmx/tdx/tdx.c-1358-\narch/x86/virt/vmx/tdx/tdx.c:1359:static __init int init_tdx_module(void)\narch/x86/virt/vmx/tdx/tdx.c-1360-{\n--\narch/x86/virt/vmx/tdx/tdx.c=1440=static __init int tdx_enable(void)\n--\narch/x86/virt/vmx/tdx/tdx.c-1469-\narch/x86/virt/vmx/tdx/tdx.c:1470:\tret = init_tdx_module();\narch/x86/virt/vmx/tdx/tdx.c-1471-\tif (ret) {\n"
}

gemini-3.1-pro-preview

null

null

							input: 13321
							output: 42
							thoughts: 26
						

Okay, here's my summary, framed as my internal thought process:

**Tracing the TDX Initialization**

Alright, let's break this down. My initial point of entry is `tdx_enable`. I know that function is the key to, well, enabling TDX. The question now becomes: how does it do that? Aha, the text points out `tdx_enable` calls `init_tdx_module`. That's the core initialization function then, the place where all the necessary setup probably happens. But I need to understand the *why* and the *when*. So, my next question is paramount: where the heck is `tdx_enable` actually *called*? Finding the call site is crucial for understanding the overall TDX enablement flow, the preconditions for it, and what triggers it in the first place. That's the next critical piece of this puzzle I need to investigate.

{
  "Expression": "tdx_enable",
  "PathPrefix": "arch/x86/virt/vmx/tdx/tdx.c"
}

{
  "Output": "arch/x86/virt/vmx/tdx/tdx.c=1359=static __init int init_tdx_module(void)\n--\narch/x86/virt/vmx/tdx/tdx.c-1439-\narch/x86/virt/vmx/tdx/tdx.c:1440:static __init int tdx_enable(void)\narch/x86/virt/vmx/tdx/tdx.c-1441-{\n--\narch/x86/virt/vmx/tdx/tdx.c-1482-}\narch/x86/virt/vmx/tdx/tdx.c:1483:subsys_initcall(tdx_enable);\narch/x86/virt/vmx/tdx/tdx.c-1484-\n"
}

gemini-3.1-pro-preview

null

null

							input: 13808
							output: 47
							thoughts: 27
						

Here's a summary of my thought process:

**Diving into the TDX Initialization**

Okay, so `tdx_enable` is declared as a `subsys_initcall`. That immediately tells me this is a core component that's initialized pretty early during the system boot process, likely before most drivers are up and running. It means it's crucial for the Trusted Domain Extensions (TDX) to be active. I need to understand what this function does. My next step is to examine the `tdx_enable` function itself. I need to get a clear picture of its role in setting up the TDX environment. This is where the real work begins.

{
  "File": "arch/x86/virt/vmx/tdx/tdx.c",
  "FirstLine": 1440,
  "LineCount": 45
}

{
  "Contents": "1440:\tstatic __init int tdx_enable(void)\n1441:\t{\n1442:\t\tenum cpuhp_state state;\n1443:\t\tint ret;\n1444:\t\n1445:\t\tif (!cpu_feature_enabled(X86_FEATURE_TDX_HOST_PLATFORM)) {\n1446:\t\t\tpr_err(\"TDX not supported by the host platform\\n\");\n1447:\t\t\treturn -ENODEV;\n1448:\t\t}\n1449:\t\n1450:\t\tif (!cpu_feature_enabled(X86_FEATURE_XSAVE)) {\n1451:\t\t\tpr_err(\"XSAVE is required for TDX\\n\");\n1452:\t\t\treturn -EINVAL;\n1453:\t\t}\n1454:\t\n1455:\t\tif (!cpu_feature_enabled(X86_FEATURE_MOVDIR64B)) {\n1456:\t\t\tpr_err(\"MOVDIR64B is required for TDX\\n\");\n1457:\t\t\treturn -EINVAL;\n1458:\t\t}\n1459:\t\n1460:\t\tif (!cpu_feature_enabled(X86_FEATURE_SELFSNOOP)) {\n1461:\t\t\tpr_err(\"Self-snoop is required for TDX\\n\");\n1462:\t\t\treturn -ENODEV;\n1463:\t\t}\n1464:\t\n1465:\t\tstate = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, \"virt/tdx:online\",\n1466:\t\t\t\t\t  tdx_online_cpu, tdx_offline_cpu);\n1467:\t\tif (state \u003c 0)\n1468:\t\t\treturn state;\n1469:\t\n1470:\t\tret = init_tdx_module();\n1471:\t\tif (ret) {\n1472:\t\t\tpr_err(\"TDX-Module initialization failed (%d)\\n\", ret);\n1473:\t\t\tcpuhp_remove_state(state);\n1474:\t\t\treturn ret;\n1475:\t\t}\n1476:\t\n1477:\t\tregister_syscore(\u0026tdx_syscore);\n1478:\t\n1479:\t\ttdx_module_state.initialized = true;\n1480:\t\tpr_info(\"TDX-Module initialized\\n\");\n1481:\t\treturn 0;\n1482:\t}\n1483:\tsubsys_initcall(tdx_enable);\n1484:\t\n"
}

gemini-3.1-pro-preview

null

null

							input: 14693
							output: 39
							thoughts: 194
						

**Investigating TDX Host Platform Support in Kernel Initialization**

Okay, so I'm looking at this `tdx_enable` function, and the first thing it does is check if the host platform supports TDX through `cpu_feature_enabled(X86_FEATURE_TDX_HOST_PLATFORM)`. Makes sense. If the host doesn't support TDX, which I'd expect given this environment, it immediately returns an error, specifically `-ENODEV`. I start wondering, can QEMU emulate the `X86_FEATURE_TDX_HOST_PLATFORM` bit? Usually, that kind of TDX host support demands actual TDX hardware, or at least a very specific QEMU configuration that's far from the norm. Wait a minute... this is Syzkaller, so this is unlikely to be running on TDX hardware! That clicks.

So, if that `X86_FEATURE_TDX_HOST_PLATFORM` feature isn't present, `tdx_enable` bails out early. Meaning, `init_tdx_module`, which subsequently calls `get_tdx_sys_info`, is never even reached. That explains the behavior I'm seeing. So, the next logical step is to pinpoint where this `X86_FEATURE_TDX_HOST_PLATFORM` is actually set. Time to go hunting in the source.

{
  "Expression": "X86_FEATURE_TDX_HOST_PLATFORM",
  "PathPrefix": "arch/x86/"
}

{
  "Output": "arch/x86/include/asm/cpufeatures.h-190-#define X86_FEATURE_CDP_L3\t\t( 7*32+ 6) /* \"cdp_l3\" Code and Data Prioritization L3 */\narch/x86/include/asm/cpufeatures.h:191:#define X86_FEATURE_TDX_HOST_PLATFORM\t( 7*32+ 7) /* \"tdx_host_platform\" Platform supports being a TDX host */\narch/x86/include/asm/cpufeatures.h-192-#define X86_FEATURE_HW_PSTATE\t\t( 7*32+ 8) /* \"hw_pstate\" AMD HW-PState */\n--\narch/x86/kvm/vmx/tdx.c=3436=int __init tdx_hardware_setup(void)\n--\narch/x86/kvm/vmx/tdx.c-3466-\narch/x86/kvm/vmx/tdx.c:3467:\tif (!cpu_feature_enabled(X86_FEATURE_TDX_HOST_PLATFORM)) {\narch/x86/kvm/vmx/tdx.c-3468-\t\tpr_err(\"TDX not supported by the host platform\\n\");\n--\narch/x86/virt/vmx/tdx/tdx.c=1440=static __init int tdx_enable(void)\n--\narch/x86/virt/vmx/tdx/tdx.c-1444-\narch/x86/virt/vmx/tdx/tdx.c:1445:\tif (!cpu_feature_enabled(X86_FEATURE_TDX_HOST_PLATFORM)) {\narch/x86/virt/vmx/tdx/tdx.c-1446-\t\tpr_err(\"TDX not supported by the host platform\\n\");\n--\narch/x86/virt/vmx/tdx/tdx.c=1582=static bool paddr_is_tdx_private(unsigned long phys)\n--\narch/x86/virt/vmx/tdx/tdx.c-1588-\narch/x86/virt/vmx/tdx/tdx.c:1589:\tif (!boot_cpu_has(X86_FEATURE_TDX_HOST_PLATFORM))\narch/x86/virt/vmx/tdx/tdx.c-1590-\t\treturn false;\n--\narch/x86/virt/vmx/tdx/tdx.c=1743=void __init tdx_init(void)\n--\narch/x86/virt/vmx/tdx/tdx.c-1794-\narch/x86/virt/vmx/tdx/tdx.c:1795:\tsetup_force_cpu_cap(X86_FEATURE_TDX_HOST_PLATFORM);\narch/x86/virt/vmx/tdx/tdx.c-1796-\n"
}

gemini-3.1-pro-preview

null

null

							input: 16001
							output: 47
							thoughts: 47
						

Okay, here's my interpretation of that thought process, assuming I'm an expert in this area:

**Deconstructing `tdx_init`'s CPU Feature Setup**

Right, that's it! `tdx_init` is calling `setup_force_cpu_cap(X86_FEATURE_TDX_HOST_PLATFORM);`. Good, that's the obvious initial step. I need to refresh my memory about `tdx_init`'s overall purpose, and this function call confirms that it is setting up the CPU features required for the TDX host platform. It's pushing that crucial `X86_FEATURE_TDX_HOST_PLATFORM` bit. I'm going to quickly refresh the bigger picture here and see where we are. Let's delve back into `tdx_init` to fully understand what's happening within the system to accommodate TDX. I need to see what else it does, what dependencies it sets up, and what potential interactions it has.

{
  "File": "arch/x86/virt/vmx/tdx/tdx.c",
  "FirstLine": 1743,
  "LineCount": 60
}

{
  "Contents": "1743:\tvoid __init tdx_init(void)\n1744:\t{\n1745:\t\tu32 tdx_keyid_start, nr_tdx_keyids;\n1746:\t\tint err;\n1747:\t\n1748:\t\terr = record_keyid_partitioning(\u0026tdx_keyid_start, \u0026nr_tdx_keyids);\n1749:\t\tif (err)\n1750:\t\t\treturn;\n1751:\t\n1752:\t\tpr_info(\"BIOS enabled: private KeyID range [%u, %u)\\n\",\n1753:\t\t\t\ttdx_keyid_start, tdx_keyid_start + nr_tdx_keyids);\n1754:\t\n1755:\t\t/*\n1756:\t\t * The TDX module itself requires one 'global KeyID' to protect\n1757:\t\t * its metadata.  If there's only one TDX KeyID, there won't be\n1758:\t\t * any left for TDX guests thus there's no point to enable TDX\n1759:\t\t * at all.\n1760:\t\t */\n1761:\t\tif (nr_tdx_keyids \u003c 2) {\n1762:\t\t\tpr_err(\"initialization failed: too few private KeyIDs available.\\n\");\n1763:\t\t\treturn;\n1764:\t\t}\n1765:\t\n1766:\t\t/*\n1767:\t\t * At this point, hibernation_available() indicates whether or\n1768:\t\t * not hibernation support has been permanently disabled.\n1769:\t\t */\n1770:\t\tif (hibernation_available()) {\n1771:\t\t\tpr_err(\"initialization failed: Hibernation support is enabled\\n\");\n1772:\t\t\treturn;\n1773:\t\t}\n1774:\t\n1775:\t\terr = register_memory_notifier(\u0026tdx_memory_nb);\n1776:\t\tif (err) {\n1777:\t\t\tpr_err(\"initialization failed: register_memory_notifier() failed (%d)\\n\",\n1778:\t\t\t\t\terr);\n1779:\t\t\treturn;\n1780:\t\t}\n1781:\t\n1782:\t#if defined(CONFIG_ACPI) \u0026\u0026 defined(CONFIG_SUSPEND)\n1783:\t\tpr_info(\"Disable ACPI S3. Turn off TDX in the BIOS to use ACPI S3.\\n\");\n1784:\t\tacpi_suspend_lowlevel = NULL;\n1785:\t#endif\n1786:\t\n1787:\t\t/*\n1788:\t\t * Just use the first TDX KeyID as the 'global KeyID' and\n1789:\t\t * leave the rest for TDX guests.\n1790:\t\t */\n1791:\t\ttdx_global_keyid = tdx_keyid_start;\n1792:\t\ttdx_guest_keyid_start = tdx_keyid_start + 1;\n1793:\t\ttdx_nr_guest_keyids = nr_tdx_keyids - 1;\n1794:\t\n1795:\t\tsetup_force_cpu_cap(X86_FEATURE_TDX_HOST_PLATFORM);\n1796:\t\n1797:\t\tcheck_tdx_erratum();\n1798:\t}\n1799:\t\n1800:\tconst struct tdx_sys_info *tdx_get_sysinfo(void)\n1801:\t{\n1802:\t\tif (!tdx_module_state.initialized)\n"
}

gemini-3.1-pro-preview

null

null

							input: 17246
							output: 45
							thoughts: 62
						

**Analyzing the TDX Initialization Process**

Okay, so I'm looking at how `tdx_init` works here. It seems that its key role, at least in this specific scenario, is to set the `X86_FEATURE_TDX_HOST_PLATFORM` bit. The condition for this is pretty straightforward: `record_keyid_partitioning` needs to be successful, and crucially, it needs to return a value, `nr_tdx_keyids`, that's greater than or equal to 2. This is interesting – it seems that the presence of *at least* two TDX key IDs is a prerequisite for enabling the TDX host platform features. The crucial piece of the puzzle, then, is understanding the inner workings of `record_keyid_partitioning`. I need to dig into that function to understand how it determines success and how it calculates this `nr_tdx_keyids` value. That's where the real logic lies, and where I can gain a deeper understanding of the platform's TDX capabilities and limitations.

{
  "Expression": "record_keyid_partitioning",
  "PathPrefix": "arch/x86/virt/vmx/tdx/tdx.c"
}

{
  "Output": "arch/x86/virt/vmx/tdx/tdx.c=1632=const char *tdx_dump_mce_info(struct mce *m)\n--\narch/x86/virt/vmx/tdx/tdx.c-1642-\narch/x86/virt/vmx/tdx/tdx.c:1643:static __init int record_keyid_partitioning(u32 *tdx_keyid_start,\narch/x86/virt/vmx/tdx/tdx.c-1644-\t\t\t\t\t    u32 *nr_tdx_keyids)\n--\narch/x86/virt/vmx/tdx/tdx.c=1743=void __init tdx_init(void)\n--\narch/x86/virt/vmx/tdx/tdx.c-1747-\narch/x86/virt/vmx/tdx/tdx.c:1748:\terr = record_keyid_partitioning(\u0026tdx_keyid_start, \u0026nr_tdx_keyids);\narch/x86/virt/vmx/tdx/tdx.c-1749-\tif (err)\n"
}

gemini-3.1-pro-preview

null

null

							input: 17897
							output: 47
							thoughts: 13
						

Okay, here's my interpretation of that thought process, tailored for an expert audience, and written in the first person:

**Initial Assessment: Navigating the Landscape of Partitioning**

Alright, I'm diving in. The first thought is clear: I'm going to take a look at `record_keyid_partitioning`. This likely means I'm about to assess a specific approach or design related to how we're breaking down and organizing data, specifically focusing on how we assign and use record keys within a partitioned structure. Given my background, I'm expecting this is either an existing system I'm familiar with, or something new that's presented itself as a potential solution or a point of interest. The naming convention "record_keyid" immediately triggers my mental database of possible applications: data warehousing, distributed databases, event streaming systems, possibly even something more niche like a specialized key-value store. I'm already formulating some initial questions: Is this a sharding strategy? Is it based on hashing, range partitioning, or something more sophisticated? What's the anticipated data volume and write/read patterns that this partitioning scheme is designed to handle? The term "partitioning" itself implies a desire for scalability, performance optimization, and potential parallel processing. I'm keen to understand how this `record_keyid_partitioning` implementation achieves those goals (or attempts to).

{
  "File": "arch/x86/virt/vmx/tdx/tdx.c",
  "FirstLine": 1643,
  "LineCount": 50
}

{
  "Contents": "1643:\tstatic __init int record_keyid_partitioning(u32 *tdx_keyid_start,\n1644:\t\t\t\t\t\t    u32 *nr_tdx_keyids)\n1645:\t{\n1646:\t\tu32 _nr_mktme_keyids, _tdx_keyid_start, _nr_tdx_keyids;\n1647:\t\tint ret;\n1648:\t\n1649:\t\t/*\n1650:\t\t * IA32_MKTME_KEYID_PARTIONING:\n1651:\t\t *   Bit [31:0]:\tNumber of MKTME KeyIDs.\n1652:\t\t *   Bit [63:32]:\tNumber of TDX private KeyIDs.\n1653:\t\t */\n1654:\t\tret = rdmsr_safe(MSR_IA32_MKTME_KEYID_PARTITIONING, \u0026_nr_mktme_keyids,\n1655:\t\t\t\t\u0026_nr_tdx_keyids);\n1656:\t\tif (ret || !_nr_tdx_keyids)\n1657:\t\t\treturn -EINVAL;\n1658:\t\n1659:\t\t/* TDX KeyIDs start after the last MKTME KeyID. */\n1660:\t\t_tdx_keyid_start = _nr_mktme_keyids + 1;\n1661:\t\n1662:\t\t*tdx_keyid_start = _tdx_keyid_start;\n1663:\t\t*nr_tdx_keyids = _nr_tdx_keyids;\n1664:\t\n1665:\t\treturn 0;\n1666:\t}\n1667:\t\n1668:\tstatic bool is_tdx_memory(unsigned long start_pfn, unsigned long end_pfn)\n1669:\t{\n1670:\t\tstruct tdx_memblock *tmb;\n1671:\t\n1672:\t\t/*\n1673:\t\t * This check assumes that the start_pfn\u003c-\u003eend_pfn range does not\n1674:\t\t * cross multiple @tdx_memlist entries.  A single memory online\n1675:\t\t * event across multiple memblocks (from which @tdx_memlist\n1676:\t\t * entries are derived at the time of module initialization) is\n1677:\t\t * not possible.  This is because memory offline/online is done\n1678:\t\t * on granularity of 'struct memory_block', and the hotpluggable\n1679:\t\t * memory region (one memblock) must be multiple of memory_block.\n1680:\t\t */\n1681:\t\tlist_for_each_entry(tmb, \u0026tdx_memlist, list) {\n1682:\t\t\tif (start_pfn \u003e= tmb-\u003estart_pfn \u0026\u0026 end_pfn \u003c= tmb-\u003eend_pfn)\n1683:\t\t\t\treturn true;\n1684:\t\t}\n1685:\t\treturn false;\n1686:\t}\n1687:\t\n1688:\tstatic int tdx_memory_notifier(struct notifier_block *nb, unsigned long action,\n1689:\t\t\t\t       void *v)\n1690:\t{\n1691:\t\tstruct memory_notify *mn = v;\n1692:\t\n"
}

gemini-3.1-pro-preview

null

null

							input: 19116
							output: 45
							thoughts: 183
						

**Investigating MKTME Key ID Partitioning in a TDX Context**

Okay, so I'm diving into this `record_keyid_partitioning` function, and it's starting by reading the `MSR_IA32_MKTME_KEYID_PARTITIONING` MSR. Now, if that MSR isn't present or if the number of TDX key IDs comes back as zero, it's throwing an `-EINVAL` error. That's straightforward enough. The next question is: can QEMU even *emulate* that MSR? My experience tells me that's generally tied to specific CPU models or certain feature flags. I need to keep that in mind.

Even if QEMU *does* emulate it, it's not the end of the line. The `tdx_enable` call triggers `init_tdx_module`, and *that* calls `get_tdx_sys_info`. Then, `get_tdx_sys_info` calls `read_sys_metadata_field`, which seems to be the crucial part. Specifically, `read_sys_metadata_field` is executing a `TDH.SYS.RD` SEAMCALL. So, *that* is the entry point to the TDX system metadata read. Alright, let's drill down into `read_sys_metadata_field` and see what it is up to.

{
  "Expression": "read_sys_metadata_field",
  "PathPrefix": "arch/x86/virt/vmx/tdx/tdx.c"
}

{
  "Output": "arch/x86/virt/vmx/tdx/tdx.c=298=static __init int build_tdx_memlist(struct list_head *tmb_list)\n--\narch/x86/virt/vmx/tdx/tdx.c-329-\narch/x86/virt/vmx/tdx/tdx.c:330:static int read_sys_metadata_field(u64 field_id, u64 *data)\narch/x86/virt/vmx/tdx/tdx.c-331-{\n--\narch/x86/virt/vmx/tdx/tdx.c=378=static int read_sys_metadata_table(const struct tdx_sys_field *fields,\n--\narch/x86/virt/vmx/tdx/tdx.c-386-\narch/x86/virt/vmx/tdx/tdx.c:387:\t\tret = read_sys_metadata_field(f-\u003efield_id, \u0026val);\narch/x86/virt/vmx/tdx/tdx.c-388-\t\tif (ret)\n--\narch/x86/virt/vmx/tdx/tdx.c=498=static __init int get_tdx_sys_info_td_conf(struct tdx_sys_info_td_conf *td_conf)\n--\narch/x86/virt/vmx/tdx/tdx.c-518-\tfor (i = 0; i \u003c td_conf-\u003enum_cpuid_config; i++) {\narch/x86/virt/vmx/tdx/tdx.c:519:\t\tret = read_sys_metadata_field(MD_FIELD_ID_CPUID_CONFIG_LEAVES + i,\narch/x86/virt/vmx/tdx/tdx.c-520-\t\t\t\t\t      \u0026td_conf-\u003ecpuid_config_leaves[i]);\n--\narch/x86/virt/vmx/tdx/tdx.c-526-\narch/x86/virt/vmx/tdx/tdx.c:527:\t\t\tret = read_sys_metadata_field(fid,\narch/x86/virt/vmx/tdx/tdx.c-528-\t\t\t\t\t\t      \u0026td_conf-\u003ecpuid_config_values[i][j]);\n"
}

gemini-3.1-pro-preview

null

null

							input: 20255
							output: 46
							thoughts: 13
						

Okay, here's my interpretation of that thought process, assuming I'm deep in my domain expertise:

**Diving into the `read_sys_metadata_field` Function**

Alright, let's pull up the documentation and the source code for `read_sys_metadata_field`. I need to understand how this function operates. My first thought is to quickly ascertain its inputs: what does it expect to receive? Is it a key, a path, some sort of identifier? And just as importantly, what's its output? Does it return the metadata directly, or some sort of handle or object that I then need to interact with? Is it raw data or is it already parsed to JSON or some other format? Knowing the input and output is *critical* for this exploration, so let's start there.

From there, I'll need to think about the underlying system. What's the storage mechanism for this system metadata? Is it a key-value store, a database, a file system? Understanding the data model is going to influence my interpretation. Are there any assumptions or pre-conditions about the structure of the metadata? Does it handle potential errors gracefully? Does it offer any type of caching to speed up the metadata retrieval, and if so, what are the implications on data consistency?

I will pay particular attention to error handling. What happens if the metadata field doesn't exist? Does it raise an exception, return a null value, or something else? Understanding the potential failure modes is key to writing robust code that interacts with it. And even more importantly, I'll assess the security implications, if any. Does this function have access to sensitive information? Are there potential vulnerabilities related to injection or unauthorized access? Finally, I need to know how this function interacts with concurrency if the environment is multithreaded. Will there be any race conditions, or is this thread-safe? Ok, let's begin.

{
  "File": "arch/x86/virt/vmx/tdx/tdx.c",
  "FirstLine": 330,
  "LineCount": 20
}

{
  "Contents": " 330:\tstatic int read_sys_metadata_field(u64 field_id, u64 *data)\n 331:\t{\n 332:\t\tstruct tdx_module_args args = {};\n 333:\t\tint ret;\n 334:\t\n 335:\t\t/*\n 336:\t\t * TDH.SYS.RD -- reads one global metadata field\n 337:\t\t *  - RDX (in): the field to read\n 338:\t\t *  - R8 (out): the field data\n 339:\t\t */\n 340:\t\targs.rdx = field_id;\n 341:\t\tret = seamcall_prerr_ret(TDH_SYS_RD, \u0026args);\n 342:\t\tif (ret)\n 343:\t\t\treturn ret;\n 344:\t\n 345:\t\t*data = args.r8;\n 346:\t\n 347:\t\treturn 0;\n 348:\t}\n 349:\t\n"
}

gemini-3.1-pro-preview

null

null

							input: 20993
							output: 34
							thoughts: 230
						

**Analyzing the Impossibility of Reaching `seamcall_prerr_ret`**

Okay, so `seamcall_prerr_ret` involves a `SEAMCALL` instruction, which is pretty niche. It's a VMX instruction, meaning it needs VMX root operation, and critically, specific hardware support – namely, an Intel TDX module loaded within the SEAM range. My immediate thought is, can this even be triggered in QEMU? And, of course, the answer is no. QEMU doesn't emulate the TDX module or `SEAMCALL`. Even if it did, the environment I work in, syzkaller, isn't set up to run with TDX emulation, at least not that I'm aware of.

That makes me wonder, does syzkaller actually *run* on real TDX hardware anywhere? The context mentions that this code path is unreachable in virtualized environments like GCE or QEMU, even with software emulated hardware. That hits home. TDX host code demands *actual* physical TDX hardware, with the TDX module loaded by the BIOS/firmware. So, this effectively means this code is inherently impossible to reach in my typical QEMU/GCE development setup.

Now, a kernel bug is a kernel bug, and I can't just throw up my hands. Is there *any* trick to try and "fake" `seamcall` so I can test around it? Okay, time to go back to basics, and check `seamcall_prerr_ret` itself and see if there are any opportunities.

{
  "Expression": "seamcall_prerr_ret",
  "PathPrefix": "arch/x86/"
}

{
  "Output": "arch/x86/virt/vmx/tdx/seamcall_internal.h=81=static __always_inline int sc_retry_prerr(sc_func_t func,\n--\narch/x86/virt/vmx/tdx/seamcall_internal.h-105-\narch/x86/virt/vmx/tdx/seamcall_internal.h:106:#define seamcall_prerr_ret(__fn, __args)\t\t\t\t\t\\\narch/x86/virt/vmx/tdx/seamcall_internal.h-107-\tsc_retry_prerr(__seamcall_ret, seamcall_err_ret, (__fn), (__args))\n--\narch/x86/virt/vmx/tdx/tdx.c=330=static int read_sys_metadata_field(u64 field_id, u64 *data)\n--\narch/x86/virt/vmx/tdx/tdx.c-340-\targs.rdx = field_id;\narch/x86/virt/vmx/tdx/tdx.c:341:\tret = seamcall_prerr_ret(TDH_SYS_RD, \u0026args);\narch/x86/virt/vmx/tdx/tdx.c-342-\tif (ret)\n--\narch/x86/virt/vmx/tdx/tdx.c=1309=static __init int init_tdmr(struct tdmr_info *tdmr)\n--\narch/x86/virt/vmx/tdx/tdx.c-1323-\narch/x86/virt/vmx/tdx/tdx.c:1324:\t\tret = seamcall_prerr_ret(TDH_SYS_TDMR_INIT, \u0026args);\narch/x86/virt/vmx/tdx/tdx.c-1325-\t\tif (ret)\n"
}

gemini-3.1-pro-preview

null

null

							input: 22096
							output: 32
							thoughts: 12
						

Okay, here's my attempt at summarizing that thought process, keeping in mind I'm speaking to a fellow expert:

**Investigating `__seamcall_ret`**

Alright, I'm diving in. Seems like we're looking at a return value, specifically `__seamcall_ret`. My initial thought is to figure out *why* we're examining this. Is it a suspected issue? Are we tracing a bug? Or are we simply trying to understand control flow more deeply in this part of the code? Given the naming convention with the double underscores, `__seamcall_ret` is likely a seam call return value, probably related to the kernel. Immediately, the question becomes: what context are we in? What's the surrounding code doing? I need to quickly recall the relevant architecture and understand the calling conventions. Let's start by checking its value, as it could point toward a number of issues.

{
  "Expression": "__seamcall_ret",
  "PathPrefix": "arch/x86/"
}

{
  "Output": "arch/x86/virt/vmx/tdx/seamcall.S=23=SYM_FUNC_END(__seamcall)\n--\narch/x86/virt/vmx/tdx/seamcall.S-25-/*\narch/x86/virt/vmx/tdx/seamcall.S:26: * __seamcall_ret() - Host-side interface functions to SEAM software\narch/x86/virt/vmx/tdx/seamcall.S-27- * (the P-SEAMLDR or the TDX module), with saving output registers to\n--\narch/x86/virt/vmx/tdx/seamcall.S-29- *\narch/x86/virt/vmx/tdx/seamcall.S:30: * __seamcall_ret() function ABI:\narch/x86/virt/vmx/tdx/seamcall.S-31- *\n--\narch/x86/virt/vmx/tdx/seamcall.S-39- */\narch/x86/virt/vmx/tdx/seamcall.S:40:SYM_FUNC_START(__seamcall_ret)\narch/x86/virt/vmx/tdx/seamcall.S-41-\tTDX_MODULE_CALL host=1 ret=1\narch/x86/virt/vmx/tdx/seamcall.S:42:SYM_FUNC_END(__seamcall_ret)\narch/x86/virt/vmx/tdx/seamcall.S-43-\n--\narch/x86/virt/vmx/tdx/seamcall_internal.h=20=u64 __seamcall(u64 fn, struct tdx_module_args *args);\narch/x86/virt/vmx/tdx/seamcall_internal.h:21:u64 __seamcall_ret(u64 fn, struct tdx_module_args *args);\narch/x86/virt/vmx/tdx/seamcall_internal.h-22-u64 __seamcall_saved_ret(u64 fn, struct tdx_module_args *args);\n--\narch/x86/virt/vmx/tdx/seamcall_internal.h=45=static __always_inline u64 sc_retry(sc_func_t func, u64 fn,\n--\narch/x86/virt/vmx/tdx/seamcall_internal.h-60-#define seamcall(_fn, _args)\t\tsc_retry(__seamcall, (_fn), (_args))\narch/x86/virt/vmx/tdx/seamcall_internal.h:61:#define seamcall_ret(_fn, _args)\tsc_retry(__seamcall_ret, (_fn), (_args))\narch/x86/virt/vmx/tdx/seamcall_internal.h-62-#define seamcall_saved_ret(_fn, _args)\tsc_retry(__seamcall_saved_ret, (_fn), (_args))\n--\narch/x86/virt/vmx/tdx/seamcall_internal.h=81=static __always_inline int sc_retry_prerr(sc_func_t func,\n--\narch/x86/virt/vmx/tdx/seamcall_internal.h-106-#define seamcall_prerr_ret(__fn, __args)\t\t\t\t\t\\\narch/x86/virt/vmx/tdx/seamcall_internal.h:107:\tsc_retry_prerr(__seamcall_ret, seamcall_err_ret, (__fn), (__args))\narch/x86/virt/vmx/tdx/seamcall_internal.h-108-\n--\narch/x86/virt/vmx/tdx/tdx.c=1582=static bool paddr_is_tdx_private(unsigned long phys)\n--\narch/x86/virt/vmx/tdx/tdx.c-1592-\t/* Get page type from the TDX module */\narch/x86/virt/vmx/tdx/tdx.c:1593:\tsret = __seamcall_dirty_cache(__seamcall_ret, TDH_PHYMEM_PAGE_RDMD, \u0026args);\narch/x86/virt/vmx/tdx/tdx.c-1594-\n"
}

gemini-3.1-pro-preview

null

null

							input: 23452
							output: 130
							thoughts: 525
						

**Unreachable Code Analysis**

Okay, let's break this down. My initial thought was triggered by the use of `__seamcall_ret` which relies on `TDX_MODULE_CALL`, using the `seamcall` instruction. Immediately, my experience tells me that this is TDX-specific, and `seamcall` *needs* TDX hardware. QEMU, in its standard configuration, doesn't emulate the TDX host platform or SEAM calls, so executing that code path directly within a QEMU environment is a non-starter.

The question then becomes: can `X86_FEATURE_TDX_HOST_PLATFORM` be set by some other means to trick things? I dug deeper. The function `record_keyid_partitioning` will read from `MSR_IA32_MKTME_KEYID_PARTITIONING`. If that read fails, we're going to hit the `-EINVAL` and therefore, `X86_FEATURE_TDX_HOST_PLATFORM` isn't going to be set, so we can't get there. Even if we *somehow* managed to bypass that check (extremely unlikely), the `seamcall` instruction itself is going to generate a #UD or fail because QEMU doesn't have the TDX host emulation necessary. We can confirm this by checking other uses of `read_sys_metadata_table` and confirm that it is only used in TDX host initialization code.

Essentially, this means that this particular code, the refactoring of TDX global metadata reading in `arch/x86/virt/vmx/tdx/tdx.c`, is part of the TDX host initialization sequence which is `tdx_init`, `tdx_enable` and `init_tdx_module`. It's fundamentally tied to the presence of real TDX hardware and a BIOS that supports it, via the `X86_FEATURE_TDX_HOST_PLATFORM` CPU feature and the `MSR_IA32_MKTME_KEYID_PARTITIONING` check. The use of `SEAMCALL` confirms this dependence on a loaded Intel TDX module in the SEAM range.

Therefore, since we're analyzing this from a fuzzing perspective, and the fuzzing environment is likely QEMU or a similarly constrained environment, it's impossible to reach and execute this code. It's not worth spending time fuzzing something that is fundamentally unreachable in the target fuzzing environment.

I will conclude that `WorthFuzzing=false`.

{
  "EnableConfigs": [],
  "FocusSymbols": [],
  "Reasoning": "The patch refactors TDX global metadata reading in the TDX host initialization code (arch/x86/virt/vmx/tdx/tdx.c). This code requires physical Intel TDX hardware, specifically the X86_FEATURE_TDX_HOST_PLATFORM CPU feature and the SEAMCALL instruction, which are not emulated in standard virtualized environments like QEMU or GCE. Therefore, this code is impossible to reach during fuzzing.",
  "WorthFuzzing": false
}

{
  "EnableConfigs": null,
  "FocusSymbols": [],
  "Reasoning": "The patch refactors TDX global metadata reading in the TDX host initialization code (arch/x86/virt/vmx/tdx/tdx.c). This code requires physical Intel TDX hardware, specifically the X86_FEATURE_TDX_HOST_PLATFORM CPU feature and the SEAMCALL instruction, which are not emulated in standard virtualized environments like QEMU or GCE. Therefore, this code is impossible to reach during fuzzing.",
  "WorthFuzzing": false
}