path: root/include/linux/kdb.h
diff options
authorDaniel Thompson <daniel.thompson@linaro.org>2014-11-07 18:37:57 +0000
committerJason Wessel <jason.wessel@windriver.com>2015-02-19 12:39:02 -0600
commitf7d4ca8bbfda23b4f1eae9b6757ff64166b093d5 (patch)
tree86344cfa2840a6401e62628e92a7591678c5150d /include/linux/kdb.h
parentdf0036d117e6c9df36324e517728e33543065f9a (diff)
kdb: Avoid printing KERN_ levels to consoles
Currently when kdb traps printk messages then the raw log level prefix (consisting of '\001' followed by a numeral) does not get stripped off before the message is issued to the various I/O handlers supported by kdb. This causes annoying visual noise as well as causing problems grepping for ^. It is also a change of behaviour compared to normal usage of printk() usage. For example <SysRq>-h ends up with different output to that of kdb's "sr h". This patch addresses the problem by stripping log levels from messages before they are issued to the I/O handlers. printk() which can also act as an i/o handler in some cases is special cased; if the caller provided a log level then the prefix will be preserved when sent to printk(). The addition of non-printable characters to the output of kdb commands is a regression, albeit and extremely elderly one, introduced by commit 04d2c8c83d0e ("printk: convert the format for KERN_<LEVEL> to a 2 byte pattern"). Note also that this patch does *not* restore the original behaviour from v3.5. Instead it makes printk() from within a kdb command display the message without any prefix (i.e. like printk() normally does). Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Joe Perches <joe@perches.com> Cc: stable@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Diffstat (limited to 'include/linux/kdb.h')
1 files changed, 7 insertions, 1 deletions
diff --git a/include/linux/kdb.h b/include/linux/kdb.h
index 75ae2e2631fc..a19bcf9e762e 100644
--- a/include/linux/kdb.h
+++ b/include/linux/kdb.h
@@ -156,8 +156,14 @@ typedef enum {
KDB_REASON_SYSTEM_NMI, /* In NMI due to SYSTEM cmd; regs valid */
} kdb_reason_t;
+enum kdb_msgsrc {
+ KDB_MSGSRC_INTERNAL, /* direct call to kdb_printf() */
+ KDB_MSGSRC_PRINTK, /* trapped from printk() */
extern int kdb_trap_printk;
-extern __printf(1, 0) int vkdb_printf(const char *fmt, va_list args);
+extern __printf(2, 0) int vkdb_printf(enum kdb_msgsrc src, const char *fmt,
+ va_list args);
extern __printf(1, 2) int kdb_printf(const char *, ...);
typedef __printf(1, 2) int (*kdb_printf_t)(const char *, ...);