[PATCH] V6 init/main.c Enable watchdog_thresh control from kernel line To: loberman@xxxxxxxxxx

From: Laurence Oberman
Date: Wed Oct 24 2018 - 15:42:05 EST

Both graphics and serial consoles are exposed to hard lockups
when handling a large amount of messaging. The kernel watchdog_thresh
parameter up to now has not been available to be set on the kernel line for
early boot.
This patch allows the setting of watchdog_thresh to be increased
when needed to avoid the hard lockups in the console code.

Signed-off-by: Laurence Oberman <loberman@xxxxxxxxxx>
Acked-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Documentation/admin-guide/kernel-parameters.txt | 7 +++++++
init/main.c | 11 +++++++++++
2 files changed, 18 insertions(+)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 4cdcd1a..102382f 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -4932,6 +4932,13 @@
or other driver-specific files in the
Documentation/watchdog/ directory.

+ watchdog_thresh=
+ This parameter allows early boot to change the
+ value of the watchdog timeout threshold from the default
+ of 10 seconds to avoid hard lockups. Example:
+ watchdog_thresh=30
+ Default: 10
If CONFIG_WQ_WATCHDOG is configured, workqueue can
warn stall conditions and dump internal state to
diff --git a/init/main.c b/init/main.c
index 1c3f902..d5511a9 100644
--- a/init/main.c
+++ b/init/main.c
@@ -1038,6 +1038,17 @@ static int __init set_debug_rodata(char *str)
__setup("rodata=", set_debug_rodata);

+extern int watchdog_thresh;
+static int __init watchdog_thresh_setup(char *str)
+ get_option(&str, &watchdog_thresh);
+ return 1;
+__setup("watchdog_thresh=", watchdog_thresh_setup);
static void mark_readonly(void)