[Crash-utility] [PATCH v2] log: fix log level print in older kernels

[John Pittman]

In older kernels, the log level and the log flags/facility are not
separated.  Since the log level is only the last three bits, and the
flags/facility and level are separated in the upstream kernel, only
print those last three bits when using 'log -m'.

Suggested-by: David Jeffery <djeffery at redhat.com>
Signed-off-by: John Pittman <jpittman at redhat.com>
---
 defs.h   | 1 +
 help.c   | 7 ++++---
 kernel.c | 2 ++
 3 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/defs.h b/defs.h
index 35cdac2..35b983a 100644
--- a/defs.h
+++ b/defs.h
@@ -5627,6 +5627,7 @@ void clone_bt_info(struct bt_info *, struct bt_info *, struct task_context *);
 void dump_kernel_table(int);
 void dump_bt_info(struct bt_info *, char *where);
 void dump_log(int);
+#define LOG_LEVEL(v) ((v) & 0x07)
 #define SHOW_LOG_LEVEL (0x1)
 #define SHOW_LOG_DICT  (0x2)
 #define SHOW_LOG_TEXT  (0x4)
diff --git a/help.c b/help.c
index 587c717..62e27d0 100644
--- a/help.c
+++ b/help.c
@@ -3904,10 +3904,11 @@ char *help_log[] = {
 "    -d  Display the dictionary of key/value pair properties that are optionally",
 "        appended to a message by the kernel's dev_printk() function; only",
 "        applicable to the variable-length record format.",
-"    -m  Display the message log level in brackets preceding each message.  For",
+"    -m  Display the message log level in brackets preceding each message. For",
 "        the variable-length record format, the level will be displayed in ",
-"        hexadecimal, and depending upon the kernel version, also contains the",
-"        facility or flags bits.",
+"        hexadecimal. In older kernels, by default, the facility/flag bits ",
+"        will be stripped to only show the level, but if needed, can still be ",
+"        shown with 'set debug 1'.",
 "    -a  Dump the audit logs remaining in kernel audit buffers that have not",
 "        been copied out to the user-space audit daemon.",
 " ",        
diff --git a/kernel.c b/kernel.c
index ac765e3..735263c 100644
--- a/kernel.c
+++ b/kernel.c
@@ -5262,6 +5262,8 @@ dump_log_entry(char *logptr, int msg_flags)
 		fprintf(fp, "%s", buf);
 	}
 
+	level = LOG_LEVEL(level);
+
 	if (msg_flags & SHOW_LOG_LEVEL) {
 		sprintf(buf, "<%x>", level);
 		ilen += strlen(buf);
-- 
2.17.2