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git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge branch 'netconsole-add-support-for-userdata-release'
Breno Leitao says:
====================
netconsole: Add support for userdata release
I am submitting a series of patches that introduce a new feature for the
netconsole subsystem, specifically the addition of the 'release' field
to the sysdata structure. This feature allows the kernel release/version
to be appended to the userdata dictionary in every message sent,
enhancing the information available for debugging and monitoring
purposes.
This complements the already supported release prepend feature, which
was added some time ago. The release prepend appends the release
information at the message header, which is not ideal for two reasons:
1) It is difficult to determine if a message includes this information,
making it hard and resource-intensive to parse.
2) When a message is fragmented, the release information is appended to
every message fragment, consuming valuable space in the packet.
The "release prepend" feature was created before the concept of userdata
and sysdata. Now that this format has proven successful, we are
implementing the release feature as part of this enhanced structure.
This patch series aims to improve the netconsole subsystem by providing
a more efficient and user-friendly way to include kernel release
information in messages. I believe these changes will significantly aid
in system analysis and troubleshooting.
Suggested-by: Manu Bretelle <chantr4@gmail.com>
Signed-off-by: Breno Leitao <leitao@debian.org>
====================
Link: https://patch.msgid.link/20250314-netcons_release-v1-0-07979c4b86af@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
+133
-7
+25
Documentation/networking/netconsole.rst
+25
Documentation/networking/netconsole.rst
···
272
272
In this example, the message was generated while "echo" was the current
273
273
scheduled process.
274
274
275
+
Kernel release auto population in userdata
276
+
------------------------------------------
277
+
278
+
Within the netconsole configfs hierarchy, there is a file named `release_enabled`
279
+
located in the `userdata` directory. This file controls the kernel release
280
+
(version) auto-population feature, which appends the kernel release information
281
+
to userdata dictionary in every message sent.
282
+
283
+
To enable the release auto-population::
284
+
285
+
echo 1 > /sys/kernel/config/netconsole/target1/userdata/release_enabled
286
+
287
+
Example::
288
+
289
+
echo "This is a message" > /dev/kmsg
290
+
12,607,22085407756,-;This is a message
291
+
release=6.14.0-rc6-01219-g3c027fbd941d
292
+
293
+
.. note::
294
+
295
+
This feature provides the same data as the "release prepend" feature.
296
+
However, in this case, the release information is appended to the userdata
297
+
dictionary rather than being included in the message header.
298
+
299
+
275
300
CPU number auto population in userdata
276
301
--------------------------------------
277
302
+67
-4
drivers/net/netconsole.c
+67
-4
drivers/net/netconsole.c
···
106
106
SYSDATA_CPU_NR = BIT(0),
107
107
/* Populate the task name (as in current->comm) in sysdata */
108
108
SYSDATA_TASKNAME = BIT(1),
109
+
/* Kernel release/version as part of sysdata */
110
+
SYSDATA_RELEASE = BIT(2),
109
111
};
110
112
111
113
/**
···
442
440
return sysfs_emit(buf, "%d\n", taskname_enabled);
443
441
}
444
442
443
+
static ssize_t sysdata_release_enabled_show(struct config_item *item,
444
+
char *buf)
445
+
{
446
+
struct netconsole_target *nt = to_target(item->ci_parent);
447
+
bool release_enabled;
448
+
449
+
mutex_lock(&dynamic_netconsole_mutex);
450
+
release_enabled = !!(nt->sysdata_fields & SYSDATA_TASKNAME);
451
+
mutex_unlock(&dynamic_netconsole_mutex);
452
+
453
+
return sysfs_emit(buf, "%d\n", release_enabled);
454
+
}
455
+
445
456
/*
446
457
* This one is special -- targets created through the configfs interface
447
458
* are not enabled (and the corresponding netpoll activated) by default.
···
734
719
entries += 1;
735
720
if (nt->sysdata_fields & SYSDATA_TASKNAME)
736
721
entries += 1;
722
+
if (nt->sysdata_fields & SYSDATA_RELEASE)
723
+
entries += 1;
737
724
738
725
return entries;
739
726
}
···
872
855
nt->extradata_complete[nt->userdata_length] = 0;
873
856
}
874
857
858
+
static ssize_t sysdata_release_enabled_store(struct config_item *item,
859
+
const char *buf, size_t count)
860
+
{
861
+
struct netconsole_target *nt = to_target(item->ci_parent);
862
+
bool release_enabled, curr;
863
+
ssize_t ret;
864
+
865
+
ret = kstrtobool(buf, &release_enabled);
866
+
if (ret)
867
+
return ret;
868
+
869
+
mutex_lock(&dynamic_netconsole_mutex);
870
+
curr = !!(nt->sysdata_fields & SYSDATA_RELEASE);
871
+
if (release_enabled == curr)
872
+
goto unlock_ok;
873
+
874
+
if (release_enabled &&
875
+
count_extradata_entries(nt) >= MAX_EXTRADATA_ITEMS) {
876
+
ret = -ENOSPC;
877
+
goto unlock;
878
+
}
879
+
880
+
if (release_enabled)
881
+
nt->sysdata_fields |= SYSDATA_RELEASE;
882
+
else
883
+
disable_sysdata_feature(nt, SYSDATA_RELEASE);
884
+
885
+
unlock_ok:
886
+
ret = strnlen(buf, count);
887
+
unlock:
888
+
mutex_unlock(&dynamic_netconsole_mutex);
889
+
return ret;
890
+
}
891
+
875
892
static ssize_t sysdata_taskname_enabled_store(struct config_item *item,
876
893
const char *buf, size_t count)
877
894
{
···
986
935
CONFIGFS_ATTR(userdatum_, value);
987
936
CONFIGFS_ATTR(sysdata_, cpu_nr_enabled);
988
937
CONFIGFS_ATTR(sysdata_, taskname_enabled);
938
+
CONFIGFS_ATTR(sysdata_, release_enabled);
989
939
990
940
static struct configfs_attribute *userdatum_attrs[] = {
991
941
&userdatum_attr_value,
···
1048
996
static struct configfs_attribute *userdata_attrs[] = {
1049
997
&sysdata_attr_cpu_nr_enabled,
1050
998
&sysdata_attr_taskname_enabled,
999
+
&sysdata_attr_release_enabled,
1051
1000
NULL,
1052
1001
};
1053
1002
···
1224
1171
init_target_config_group(nt, target_name);
1225
1172
}
1226
1173
1227
-
static int append_cpu_nr(struct netconsole_target *nt, int offset)
1174
+
static int sysdata_append_cpu_nr(struct netconsole_target *nt, int offset)
1228
1175
{
1229
1176
/* Append cpu=%d at extradata_complete after userdata str */
1230
1177
return scnprintf(&nt->extradata_complete[offset],
···
1232
1179
raw_smp_processor_id());
1233
1180
}
1234
1181
1235
-
static int append_taskname(struct netconsole_target *nt, int offset)
1182
+
static int sysdata_append_taskname(struct netconsole_target *nt, int offset)
1236
1183
{
1237
1184
return scnprintf(&nt->extradata_complete[offset],
1238
1185
MAX_EXTRADATA_ENTRY_LEN, " taskname=%s\n",
1239
1186
current->comm);
1240
1187
}
1188
+
1189
+
static int sysdata_append_release(struct netconsole_target *nt, int offset)
1190
+
{
1191
+
return scnprintf(&nt->extradata_complete[offset],
1192
+
MAX_EXTRADATA_ENTRY_LEN, " release=%s\n",
1193
+
init_utsname()->release);
1194
+
}
1195
+
1241
1196
/*
1242
1197
* prepare_extradata - append sysdata at extradata_complete in runtime
1243
1198
* @nt: target to send message to
···
1264
1203
goto out;
1265
1204
1266
1205
if (nt->sysdata_fields & SYSDATA_CPU_NR)
1267
-
extradata_len += append_cpu_nr(nt, extradata_len);
1206
+
extradata_len += sysdata_append_cpu_nr(nt, extradata_len);
1268
1207
if (nt->sysdata_fields & SYSDATA_TASKNAME)
1269
-
extradata_len += append_taskname(nt, extradata_len);
1208
+
extradata_len += sysdata_append_taskname(nt, extradata_len);
1209
+
if (nt->sysdata_fields & SYSDATA_RELEASE)
1210
+
extradata_len += sysdata_append_release(nt, extradata_len);
1270
1211
1271
1212
WARN_ON_ONCE(extradata_len >
1272
1213
MAX_EXTRADATA_ENTRY_LEN * MAX_EXTRADATA_ITEMS);
+41
-3
tools/testing/selftests/drivers/net/netcons_sysdata.sh
+41
-3
tools/testing/selftests/drivers/net/netcons_sysdata.sh
···
42
42
echo 1 > "${NETCONS_PATH}/userdata/taskname_enabled"
43
43
}
44
44
45
+
# Enable the release to be appended to sysdata
46
+
function set_release() {
47
+
if [[ ! -f "${NETCONS_PATH}/userdata/release_enabled" ]]
48
+
then
49
+
echo "Not able to enable release sysdata append. Configfs not available in ${NETCONS_PATH}/userdata/release_enabled" >&2
50
+
exit "${ksft_skip}"
51
+
fi
52
+
53
+
echo 1 > "${NETCONS_PATH}/userdata/release_enabled"
54
+
}
55
+
45
56
# Disable the sysdata cpu_nr feature
46
57
function unset_cpu_nr() {
47
58
echo 0 > "${NETCONS_PATH}/userdata/cpu_nr_enabled"
···
61
50
# Once called, taskname=<..> will not be appended anymore
62
51
function unset_taskname() {
63
52
echo 0 > "${NETCONS_PATH}/userdata/taskname_enabled"
53
+
}
54
+
55
+
function unset_release() {
56
+
echo 0 > "${NETCONS_PATH}/userdata/release_enabled"
64
57
}
65
58
66
59
# Test if MSG contains sysdata
···
108
93
pkill_socat
109
94
}
110
95
96
+
function validate_release() {
97
+
RELEASE=$(uname -r)
98
+
99
+
if [ ! -f "$OUTPUT_FILE" ]; then
100
+
echo "FAIL: File was not generated." >&2
101
+
exit "${ksft_fail}"
102
+
fi
103
+
104
+
if ! grep -q "release=${RELEASE}" "${OUTPUT_FILE}"; then
105
+
echo "FAIL: 'release=${RELEASE}' not found in ${OUTPUT_FILE}" >&2
106
+
cat "${OUTPUT_FILE}" >&2
107
+
exit "${ksft_fail}"
108
+
fi
109
+
}
110
+
111
111
# Test if MSG content exists in OUTPUT_FILE but no `cpu=` and `taskname=`
112
112
# strings
113
113
function validate_no_sysdata() {
···
145
115
146
116
if grep -q "taskname=" "${OUTPUT_FILE}"; then
147
117
echo "FAIL: 'taskname= found in ${OUTPUT_FILE}" >&2
118
+
cat "${OUTPUT_FILE}" >&2
119
+
exit "${ksft_fail}"
120
+
fi
121
+
122
+
if grep -q "release=" "${OUTPUT_FILE}"; then
123
+
echo "FAIL: 'release= found in ${OUTPUT_FILE}" >&2
148
124
cat "${OUTPUT_FILE}" >&2
149
125
exit "${ksft_fail}"
150
126
fi
···
205
169
set_cpu_nr
206
170
# Enable taskname to be appended to sysdata
207
171
set_taskname
172
+
set_release
208
173
runtest
209
174
# Make sure the message was received in the dst part
210
175
# and exit
176
+
validate_release
211
177
validate_sysdata
212
178
213
179
#====================================================
···
222
184
MSG="Test #2 from CPU${CPU}"
223
185
set_user_data
224
186
runtest
187
+
validate_release
225
188
validate_sysdata
226
189
227
190
# ===================================================
228
191
# TEST #3
229
-
# Unset cpu_nr, so, no CPU should be appended.
230
-
# userdata is still set
192
+
# Unset all sysdata, fail if any userdata is set
231
193
# ===================================================
232
194
CPU=$((RANDOM % $(nproc)))
233
195
OUTPUT_FILE="/tmp/${TARGET}_3"
234
196
MSG="Test #3 from CPU${CPU}"
235
-
# Enable the auto population of cpu_nr
236
197
unset_cpu_nr
237
198
unset_taskname
199
+
unset_release
238
200
runtest
239
201
# At this time, cpu= shouldn't be present in the msg
240
202
validate_no_sysdata