From: Andrew Cooper <andrew.cooper3@citrix.com>
To: Xen-devel <xen-devel@lists.xen.org>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>,
Ian Jackson <Ian.Jackson@eu.citrix.com>,
Wei Liu <wei.liu2@citrix.com>
Subject: [PATCH v3 25/28] tools: Utility for dealing with featuresets
Date: Tue, 15 Mar 2016 15:35:21 +0000 [thread overview]
Message-ID: <1458056124-8024-26-git-send-email-andrew.cooper3@citrix.com> (raw)
In-Reply-To: <1458056124-8024-1-git-send-email-andrew.cooper3@citrix.com>
It is able to reports the current featuresets; both the static masks and
dynamic featuresets from Xen, or to decode an arbitrary featureset into
`/proc/cpuinfo` style strings.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
---
CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
v2: No linking hackary
---
.gitignore | 1 +
tools/misc/Makefile | 4 +
tools/misc/xen-cpuid.c | 394 +++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 399 insertions(+)
create mode 100644 tools/misc/xen-cpuid.c
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..608c488
--- /dev/null
+++ b/tools/misc/xen-cpuid.c
@@ -0,0 +1,394 @@
+#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 )
+ {
+ case 'h':
+ option_error:
+ 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;
+
+ default:
+ printf("Bad option '%c'\n", c);
+ goto option_error;
+ }
+ }
+
+ 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:
+ */
--
2.1.4
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel
next prev parent reply other threads:[~2016-03-15 15:35 UTC|newest]
Thread overview: 88+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-03-15 15:34 [PATCH RFC v3 00/28] x86: Improvements to cpuid handling for guests Andrew Cooper
2016-03-15 15:34 ` [PATCH v3 01/28] xen/x86: Drop unused and non-useful feature definitions Andrew Cooper
2016-03-16 7:53 ` Konrad Rzeszutek Wilk
2016-03-16 9:49 ` Andrew Cooper
2016-03-22 14:06 ` Doug Goldstein
2016-03-22 14:38 ` Jan Beulich
2016-03-15 15:34 ` [PATCH v3 02/28] xen/x86: Rename features to be closer to the vendor definitions Andrew Cooper
2016-03-16 8:01 ` Konrad Rzeszutek Wilk
2016-03-17 19:46 ` Andrew Cooper
2016-03-15 15:34 ` [PATCH v3 03/28] xen/public: Export cpu featureset information in the public API Andrew Cooper
2016-03-16 8:32 ` Konrad Rzeszutek Wilk
2016-03-22 10:39 ` Andrew Cooper
2016-03-18 15:52 ` Jan Beulich
2016-03-15 15:35 ` [PATCH v3 04/28] xen/x86: Script to automatically process featureset information Andrew Cooper
2016-03-16 8:41 ` Konrad Rzeszutek Wilk
2016-03-15 15:35 ` [PATCH v3 05/28] xen/x86: Collect more cpuid feature leaves Andrew Cooper
2016-03-16 8:50 ` Konrad Rzeszutek Wilk
2016-03-15 15:35 ` [PATCH v3 06/28] xen/x86: Mask out unknown features from Xen's capabilities Andrew Cooper
2016-03-16 18:01 ` Konrad Rzeszutek Wilk
2016-03-15 15:35 ` [PATCH v3 07/28] xen/x86: Annotate special features Andrew Cooper
2016-03-16 18:04 ` Konrad Rzeszutek Wilk
2016-03-18 16:29 ` Jan Beulich
2016-03-15 15:35 ` [PATCH v3 08/28] xen/x86: Annotate VM applicability in featureset Andrew Cooper
2016-03-16 18:15 ` Konrad Rzeszutek Wilk
2016-03-18 16:57 ` Jan Beulich
2016-03-18 18:56 ` Andrew Cooper
2016-03-21 11:53 ` Jan Beulich
2016-03-21 13:39 ` Andrew Cooper
2016-03-15 15:35 ` [PATCH v3 09/28] xen/x86: Calculate maximum host and guest featuresets Andrew Cooper
2016-03-16 18:24 ` Konrad Rzeszutek Wilk
2016-03-18 17:09 ` Jan Beulich
2016-03-22 11:23 ` Andrew Cooper
2016-03-22 12:39 ` Jan Beulich
2016-03-22 14:37 ` Andrew Cooper
2016-03-22 14:52 ` Jan Beulich
2016-03-22 15:01 ` Andrew Cooper
2016-03-22 16:10 ` Jan Beulich
2016-03-15 15:35 ` [PATCH v3 10/28] xen/x86: Generate deep dependencies of features Andrew Cooper
2016-03-17 19:45 ` Konrad Rzeszutek Wilk
2016-03-17 20:14 ` Andrew Cooper
2016-03-17 20:32 ` Konrad Rzeszutek Wilk
2016-03-21 15:41 ` Jan Beulich
2016-03-15 15:35 ` [PATCH v3 11/28] xen/x86: Clear dependent features when clearing a cpu cap Andrew Cooper
2016-03-17 19:51 ` Konrad Rzeszutek Wilk
2016-03-17 19:56 ` Andrew Cooper
2016-03-28 15:02 ` Konrad Rzeszutek Wilk
2016-03-21 15:45 ` Jan Beulich
2016-03-15 15:35 ` [PATCH v3 12/28] xen/x86: Improve disabling of features which have dependencies Andrew Cooper
2016-03-15 15:35 ` [PATCH v3 13/28] xen/x86: Improvements to in-hypervisor cpuid sanity checks Andrew Cooper
2016-03-21 16:11 ` Jan Beulich
2016-03-22 15:30 ` Andrew Cooper
2016-03-15 15:35 ` [PATCH v3 14/28] x86/cpu: Move set_cpumask() calls into c_early_init() Andrew Cooper
2016-03-21 16:16 ` Jan Beulich
2016-03-15 15:35 ` [PATCH v3 15/28] x86/cpu: Sysctl and common infrastructure for levelling context switching Andrew Cooper
2016-03-15 17:35 ` Joao Martins
2016-03-15 19:29 ` Andrew Cooper
2016-03-15 19:34 ` Joao Martins
2016-03-21 16:23 ` Jan Beulich
2016-03-22 15:57 ` Andrew Cooper
2016-03-22 16:16 ` Jan Beulich
2016-03-15 15:35 ` [PATCH v3 16/28] x86/cpu: Rework AMD masking MSR setup Andrew Cooper
2016-03-21 16:51 ` Jan Beulich
2016-03-21 16:55 ` Andrew Cooper
2016-03-15 15:35 ` [PATCH v3 17/28] x86/cpu: Rework Intel masking/faulting setup Andrew Cooper
2016-03-21 16:44 ` Jan Beulich
2016-03-15 15:35 ` [PATCH v3 18/28] x86/cpu: Context switch cpuid masks and faulting state in context_switch() Andrew Cooper
2016-03-15 15:35 ` [PATCH v3 19/28] x86/pv: Provide custom cpumasks for PV domains Andrew Cooper
2016-03-21 16:53 ` Jan Beulich
2016-03-15 15:35 ` [PATCH v3 20/28] x86/domctl: Update PV domain cpumasks when setting cpuid policy Andrew Cooper
2016-03-21 17:06 ` Jan Beulich
2016-03-22 16:37 ` Andrew Cooper
2016-03-22 16:51 ` Jan Beulich
2016-03-15 15:35 ` [PATCH v3 21/28] xen+tools: Export maximum host and guest cpu featuresets via SYSCTL Andrew Cooper
2016-03-16 18:23 ` Wei Liu
2016-03-16 20:38 ` David Scott
2016-03-22 8:43 ` Jan Beulich
2016-03-22 20:39 ` Andrew Cooper
2016-03-15 15:35 ` [PATCH v3 22/28] tools/libxc: Modify bitmap operations to take void pointers Andrew Cooper
2016-03-16 15:24 ` Andrew Cooper
2016-03-17 12:17 ` Wei Liu
2016-03-15 15:35 ` [PATCH v3 23/28] tools/libxc: Use public/featureset.h for cpuid policy generation Andrew Cooper
2016-03-15 15:35 ` [PATCH v3 24/28] tools/libxc: Expose the automatically generated cpu featuremask information Andrew Cooper
2016-03-15 15:35 ` Andrew Cooper [this message]
2016-03-16 18:23 ` [PATCH v3 25/28] tools: Utility for dealing with featuresets Wei Liu
2016-03-15 15:35 ` [PATCH v3 26/28] tools/libxc: Wire a featureset through to cpuid policy logic Andrew Cooper
2016-03-15 15:35 ` [PATCH v3 27/28] tools/libxc: Use featuresets rather than guesswork Andrew Cooper
2016-03-15 15:35 ` [PATCH v3 28/28] tools/libxc: Calculate xstate cpuid leaf from guest information Andrew Cooper
2016-03-16 18:23 ` Wei Liu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1458056124-8024-26-git-send-email-andrew.cooper3@citrix.com \
--to=andrew.cooper3@citrix.com \
--cc=Ian.Jackson@eu.citrix.com \
--cc=wei.liu2@citrix.com \
--cc=xen-devel@lists.xen.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).