[PATCH_V2 1/2] fix the bug that printk can't supportprintk(KERN_LEVEL)

[he, bo]

From: he bo <bo.he@xxxxxxxxx>

Usually, there is a special scenario that developer wants to
call printk to just set up a log level (might be transferred
here as a parameter from upper level), then, later calling
of printk prints out real string with the same log level
continuously.

Current function vprintk has an issue to support this capability.
When the whole string in one calling to printk is just a log level,
it ignores it.

Signed-off-by: he, bo <bo.he@xxxxxxxxx>
Reviewed-by: Zhang, Yanmin <yanmin.zhang@xxxxxxxxx>
---
 kernel/printk.c |    7 ++++---
 1 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/kernel/printk.c b/kernel/printk.c
index b663c2c..473afdb 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -909,7 +909,7 @@ asmlinkage int vprintk(const char *fmt, va_list args)
 	 * Copy the output into log_buf. If the caller didn't provide
 	 * the appropriate log prefix, we insert them here
 	 */
-	for (; *p; p++) {
+	for (; plen || *p; p++) {
 		if (new_text_line) {
 			new_text_line = 0;
 
@@ -920,6 +920,7 @@ asmlinkage int vprintk(const char *fmt, va_list args)
 				for (i = 0; i < plen; i++)
 					emit_log_char(printk_buf[i]);
 				printed_len += plen;
+				plen = 0;
 			} else {
 				/* Add log prefix */
 				emit_log_char('<');
@@ -946,10 +947,10 @@ asmlinkage int vprintk(const char *fmt, va_list args)
 				printed_len += tlen;
 			}
 
-			if (!*p)
-				break;
 		}
 
+		if (!*p)
+			break;
 		emit_log_char(*p);
 		if (*p == '\n')
 			new_text_line = 1;
-- 
1.7.1



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/