[PATCH 3.17-rc4 1/3] kdb: Fix a prompt management bug when using | grep

[Daniel Thompson]

Currently when the "| grep" feature is used to filter the output of a
command then the prompt is not displayed for the subsequent command.
Likewise any characters typed by the user are also not echoed to the
display. This rather disconcerting problem eventually corrects itself
when the user presses Enter the kdb_grepping_flag is cleared when
kdb_parse() tries to make sense of whatever they typed.

This patch resolves the problem by moving the clearing of this flag
from the middle of command processing to the beginning.

Signed-off-by: Daniel Thompson <daniel.thompson@xxxxxxxxxx>
---
 kernel/debug/kdb/kdb_main.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index 379650b..9d10cb2 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -872,13 +872,12 @@ int kdb_parse(const char *cmdstr)
 	char *cp;
 	char *cpp, quoted;
 	kdbtab_t *tp;
-	int i, escaped, ignore_errors = 0, check_grep;
+	int i, escaped, ignore_errors = 0, check_grep = 0;
 
 	/*
 	 * First tokenize the command string.
 	 */
 	cp = (char *)cmdstr;
-	kdb_grepping_flag = check_grep = 0;
 
 	if (KDB_FLAG(CMD_INTERRUPT)) {
 		/* Previous command was interrupted, newline must not
@@ -1241,6 +1240,7 @@ static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs,
 		 */
 		kdb_nextline = 1;
 		KDB_STATE_CLEAR(SUPPRESS);
+		kdb_grepping_flag = 0;
 
 		cmdbuf = cmd_cur;
 		*cmdbuf = '\0';
-- 
1.9.3

--
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/