diff --git a/.gitignore b/.gitignore
index b40453e..20ffa2d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -179,6 +179,7 @@ tools/misc/cpuperf/cpuperf-perfcntr
 tools/misc/cpuperf/cpuperf-xen
 tools/misc/xc_shadow
 tools/misc/xen_cpuperf
+tools/misc/xen-cpuid
 tools/misc/xen-detect
 tools/misc/xen-tmem-list-parse
 tools/misc/xenperf
diff --git a/tools/misc/Makefile b/tools/misc/Makefile
index a2ef0ec..a94dad9 100644
--- a/tools/misc/Makefile
+++ b/tools/misc/Makefile
@@ -10,6 +10,7 @@ CFLAGS += $(CFLAGS_xeninclude)
 CFLAGS += $(CFLAGS_libxenstore)
 
 # Everything to be installed in regular bin/
+INSTALL_BIN-$(CONFIG_X86)      += xen-cpuid
 INSTALL_BIN-$(CONFIG_X86)      += xen-detect
 INSTALL_BIN                    += xencons
 INSTALL_BIN                    += xencov_split
@@ -68,6 +69,9 @@ clean:
 .PHONY: distclean
 distclean: clean
 
+xen-cpuid: xen-cpuid.o
+	$(CC) $(LDFLAGS) -o $@ $< $(LDLIBS_libxenctrl) $(LDLIBS_libxenguest) $(APPEND_LDFLAGS)
+
 xen-hvmctx: xen-hvmctx.o
 	$(CC) $(LDFLAGS) -o $@ $< $(LDLIBS_libxenctrl) $(APPEND_LDFLAGS)
 
diff --git a/tools/misc/xen-cpuid.c b/tools/misc/xen-cpuid.c
new file mode 100644
index 0000000..44991f6
--- /dev/null
+++ b/tools/misc/xen-cpuid.c
@@ -0,0 +1,392 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <err.h>
+#include <getopt.h>
+#include <string.h>
+
+#include <xenctrl.h>
+
+#define ARRAY_SIZE(a) (sizeof a / sizeof *a)
+static uint32_t nr_features;
+
+static const char *str_1d[32] =
+{
+    [ 0] = "fpu",  [ 1] = "vme",
+    [ 2] = "de",   [ 3] = "pse",
+    [ 4] = "tsc",  [ 5] = "msr",
+    [ 6] = "pae",  [ 7] = "mce",
+    [ 8] = "cx8",  [ 9] = "apic",
+    [10] = "REZ",  [11] = "sysenter",
+    [12] = "mtrr", [13] = "pge",
+    [14] = "mca",  [15] = "cmov",
+    [16] = "pat",  [17] = "pse36",
+    [18] = "psn",  [19] = "clflush",
+    [20] = "REZ",  [21] = "ds",
+    [22] = "acpi", [23] = "mmx",
+    [24] = "fxsr", [25] = "sse",
+    [26] = "sse2", [27] = "ss",
+    [28] = "htt",  [29] = "tm",
+    [30] = "ia64", [31] = "pbe",
+};
+
+static const char *str_1c[32] =
+{
+    [ 0] = "sse3",    [ 1] = "pclmulqdq",
+    [ 2] = "dtes64",  [ 3] = "monitor",
+    [ 4] = "ds-cpl",  [ 5] = "vmx",
+    [ 6] = "smx",     [ 7] = "est",
+    [ 8] = "tm2",     [ 9] = "ssse3",
+    [10] = "cntx-id", [11] = "sdgb",
+    [12] = "fma",     [13] = "cx16",
+    [14] = "xtpr",    [15] = "pdcm",
+    [16] = "REZ",     [17] = "pcid",
+    [18] = "dca",     [19] = "sse41",
+    [20] = "sse42",   [21] = "x2apic",
+    [22] = "movebe",  [23] = "popcnt",
+    [24] = "tsc-dl",  [25] = "aesni",
+    [26] = "xsave",   [27] = "osxsave",
+    [28] = "avx",     [29] = "f16c",
+    [30] = "rdrnd",   [31] = "hyper",
+};
+
+static const char *str_e1d[32] =
+{
+    [ 0] = "fpu",    [ 1] = "vme",
+    [ 2] = "de",     [ 3] = "pse",
+    [ 4] = "tsc",    [ 5] = "msr",
+    [ 6] = "pae",    [ 7] = "mce",
+    [ 8] = "cx8",    [ 9] = "apic",
+    [10] = "REZ",    [11] = "syscall",
+    [12] = "mtrr",   [13] = "pge",
+    [14] = "mca",    [15] = "cmov",
+    [16] = "fcmov",  [17] = "pse36",
+    [18] = "REZ",    [19] = "mp",
+    [20] = "nx",     [21] = "REZ",
+    [22] = "mmx+",   [23] = "mmx",
+    [24] = "fxsr",   [25] = "fxsr+",
+    [26] = "pg1g",   [27] = "rdtscp",
+    [28] = "REZ",    [29] = "lm",
+    [30] = "3dnow+", [31] = "3dnow",
+};
+
+static const char *str_e1c[32] =
+{
+    [ 0] = "lahf_lm",    [ 1] = "cmp",
+    [ 2] = "svm",        [ 3] = "extapic",
+    [ 4] = "cr8d",       [ 5] = "lzcnt",
+    [ 6] = "sse4a",      [ 7] = "msse",
+    [ 8] = "3dnowpf",    [ 9] = "osvw",
+    [10] = "ibs",        [11] = "xop",
+    [12] = "skinit",     [13] = "wdt",
+    [14] = "REZ",        [15] = "lwp",
+    [16] = "fma4",       [17] = "tce",
+    [18] = "REZ",        [19] = "nodeid",
+    [20] = "REZ",        [21] = "tbm",
+    [22] = "topoext",    [23] = "perfctr_core",
+    [24] = "perfctr_nb", [25] = "REZ",
+    [26] = "dbx",        [27] = "perftsc",
+    [28] = "pcx_l2i",    [29] = "monitorx",
+
+    [30 ... 31] = "REZ",
+};
+
+static const char *str_7b0[32] =
+{
+    [ 0] = "fsgsbase", [ 1] = "tsc-adj",
+    [ 2] = "sgx",      [ 3] = "bmi1",
+    [ 4] = "hle",      [ 5] = "avx2",
+    [ 6] = "REZ",      [ 7] = "smep",
+    [ 8] = "bmi2",     [ 9] = "erms",
+    [10] = "invpcid",  [11] = "rtm",
+    [12] = "pqm",      [13] = "depfpp",
+    [14] = "mpx",      [15] = "pqe",
+    [16] = "avx512f",  [17] = "avx512dq",
+    [18] = "rdseed",   [19] = "adx",
+    [20] = "smap",     [21] = "avx512ifma",
+    [22] = "pcomit",   [23] = "clflushopt",
+    [24] = "clwb",     [25] = "pt",
+    [26] = "avx512pf", [27] = "avx512er",
+    [28] = "avx512cd", [29] = "sha",
+    [30] = "avx512bw", [31] = "avx512vl",
+};
+
+static const char *str_Da1[32] =
+{
+    [ 0] = "xsaveopt", [ 1] = "xsavec",
+    [ 2] = "xgetbv1",  [ 3] = "xsaves",
+
+    [4 ... 31] = "REZ",
+};
+
+static const char *str_7c0[32] =
+{
+    [ 0] = "prechwt1", [ 1] = "avx512vbmi",
+    [ 2] = "REZ",      [ 3] = "pku",
+    [ 4] = "ospke",
+
+    [5 ... 31] = "REZ",
+};
+
+static const char *str_e7d[32] =
+{
+    [0 ... 7] = "REZ",
+
+    [ 8] = "itsc",
+
+    [9 ... 31] = "REZ",
+};
+
+static const char *str_e8b[32] =
+{
+    [ 0] = "clzero",
+
+    [1 ... 31] = "REZ",
+};
+
+static struct {
+    const char *name;
+    const char *abbr;
+    const char **strs;
+} decodes[] =
+{
+    { "0x00000001.edx",   "1d",  str_1d },
+    { "0x00000001.ecx",   "1c",  str_1c },
+    { "0x80000001.edx",   "e1d", str_e1d },
+    { "0x80000001.ecx",   "e1c", str_e1c },
+    { "0x0000000d:1.eax", "Da1", str_Da1 },
+    { "0x00000007:0.ebx", "7b0", str_7b0 },
+    { "0x00000007:0.ecx", "7c0", str_7c0 },
+    { "0x80000007.edx",   "e7d", str_e7d },
+    { "0x80000008.ebx",   "e8b", str_e8b },
+};
+
+#define COL_ALIGN "18"
+
+static struct fsinfo {
+    const char *name;
+    uint32_t len;
+    uint32_t *fs;
+} featuresets[] =
+{
+    [XEN_SYSCTL_cpu_featureset_host] = { "Host", 0, NULL },
+    [XEN_SYSCTL_cpu_featureset_raw]  = { "Raw",  0, NULL },
+    [XEN_SYSCTL_cpu_featureset_pv]   = { "PV",   0, NULL },
+    [XEN_SYSCTL_cpu_featureset_hvm]  = { "HVM",  0, NULL },
+};
+
+static void dump_leaf(uint32_t leaf, const char **strs)
+{
+    unsigned i;
+
+    if ( !strs )
+    {
+        printf(" ???");
+        return;
+    }
+
+    for ( i = 0; i < 32; ++i )
+        if ( leaf & (1u << i) )
+            printf(" %s", strs[i] ?: "???" );
+}
+
+static void decode_featureset(const uint32_t *features,
+                              const uint32_t length,
+                              const char *name,
+                              bool detail)
+{
+    unsigned int i;
+
+    printf("%-"COL_ALIGN"s        ", name);
+    for ( i = 0; i < length; ++i )
+        printf("%08x%c", features[i],
+               i < length - 1 ? ':' : '\n');
+
+    if ( !detail )
+        return;
+
+    for ( i = 0; i < length && i < ARRAY_SIZE(decodes); ++i )
+    {
+        printf("  [%02u] %-"COL_ALIGN"s", i, decodes[i].name ?: "<UNKNOWN>");
+        if ( decodes[i].name )
+            dump_leaf(features[i], decodes[i].strs);
+        printf("\n");
+    }
+}
+
+static void get_featureset(xc_interface *xch, unsigned int idx)
+{
+    struct fsinfo *f = &featuresets[idx];
+
+    f->len = xc_get_cpu_featureset_size();
+    f->fs = calloc(nr_features, sizeof(*f->fs));
+
+    if ( !f->fs )
+        err(1, "calloc(, featureset)");
+
+    if ( xc_get_cpu_featureset(xch, idx, &f->len, f->fs) )
+        err(1, "xc_get_featureset()");
+}
+
+static void dump_info(xc_interface *xch, bool detail)
+{
+    unsigned int i;
+
+    printf("nr_features: %u\n", nr_features);
+
+    if ( !detail )
+    {
+        printf("       %"COL_ALIGN"s ", "KEY");
+        for ( i = 0; i < ARRAY_SIZE(decodes); ++i )
+            printf("%-8s ", decodes[i].abbr ?: "???");
+        printf("\n");
+    }
+
+    printf("\nStatic sets:\n");
+    decode_featureset(xc_get_static_cpu_featuremask(XC_FEATUREMASK_KNOWN),
+                      nr_features, "Known", detail);
+    decode_featureset(xc_get_static_cpu_featuremask(XC_FEATUREMASK_SPECIAL),
+                      nr_features, "Special", detail);
+    decode_featureset(xc_get_static_cpu_featuremask(XC_FEATUREMASK_PV),
+                      nr_features, "PV Mask", detail);
+    decode_featureset(xc_get_static_cpu_featuremask(XC_FEATUREMASK_HVM_SHADOW),
+                      nr_features, "HVM Shadow Mask", detail);
+    decode_featureset(xc_get_static_cpu_featuremask(XC_FEATUREMASK_HVM_HAP),
+                      nr_features, "HVM Hap Mask", detail);
+
+    printf("\nDynamic sets:\n");
+    for ( i = 0; i < ARRAY_SIZE(featuresets); ++i )
+    {
+        get_featureset(xch, i);
+
+        decode_featureset(featuresets[i].fs, featuresets[i].len,
+                          featuresets[i].name, detail);
+    }
+
+    for ( i = 0; i < ARRAY_SIZE(featuresets); ++i )
+        free(featuresets[i].fs);
+}
+
+int main(int argc, char **argv)
+{
+    enum { MODE_UNKNOWN, MODE_INFO, MODE_DETAIL, MODE_INTERPRET }
+    mode = MODE_UNKNOWN;
+
+    nr_features = xc_get_cpu_featureset_size();
+
+    for ( ;; )
+    {
+        int option_index = 0, c;
+        static struct option long_options[] =
+        {
+            { "help", no_argument, NULL, 'h' },
+            { "info", no_argument, NULL, 'i' },
+            { "detail", no_argument, NULL, 'd' },
+            { "verbose", no_argument, NULL, 'v' },
+            { NULL, 0, NULL, 0 },
+        };
+
+        c = getopt_long(argc, argv, "hidv", long_options, &option_index);
+
+        if ( c == -1 )
+            break;
+
+        switch ( c )
+        {
+        default:
+            printf("Bad option '%c'\n", c);
+            /* Fallthough */
+        case 'h':
+            printf("Usage: %s [ info | detail | <featureset>* ]\n", argv[0]);
+            return 0;
+
+        case 'i':
+            mode = MODE_INFO;
+            break;
+
+        case 'd':
+        case 'v':
+            mode = MODE_DETAIL;
+            break;
+        }
+    }
+
+    if ( mode == MODE_UNKNOWN )
+    {
+        if ( optind == argc )
+            mode = MODE_INFO;
+        else if ( optind < argc )
+        {
+            if ( !strcmp(argv[optind], "info") )
+            {
+                mode = MODE_INFO;
+                optind++;
+            }
+            else if ( !strcmp(argv[optind], "detail") )
+            {
+                mode = MODE_DETAIL;
+                optind++;
+            }
+            else
+                mode = MODE_INTERPRET;
+        }
+        else
+            mode = MODE_INTERPRET;
+    }
+
+    if ( mode == MODE_INFO || mode == MODE_DETAIL )
+    {
+        xc_interface *xch = xc_interface_open(0, 0, 0);
+
+        if ( !xch )
+            err(1, "xc_interface_open");
+
+        if ( xc_get_cpu_featureset(xch, 0, &nr_features, NULL) )
+            err(1, "xc_get_featureset(, NULL)");
+
+        dump_info(xch, mode == MODE_DETAIL);
+
+        xc_interface_close(xch);
+    }
+    else
+    {
+        uint32_t fs[nr_features + 1];
+
+        while ( optind < argc )
+        {
+            char *ptr = argv[optind++];
+            unsigned int i = 0;
+            int offset;
+
+            memset(fs, 0, sizeof(fs));
+
+            while ( sscanf(ptr, "%x%n", &fs[i], &offset) == 1 )
+            {
+                i++;
+                ptr += offset;
+
+                if ( i == nr_features )
+                    break;
+
+                if ( *ptr == ':' )
+                {
+                    ptr++; continue;
+                }
+                break;
+            }
+
+            decode_featureset(fs, i, "Raw", true);
+        }
+    }
+
+    return 0;
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
