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 <lober...@redhat.com>
Acked-by: Randy Dunlap <rdun...@infradead.org>
---
 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
+
        workqueue.watchdog_thresh=
                        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);
 #endif
 
+#ifdef CONFIG_LOCKUP_DETECTOR
+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);
+#endif
+
 #ifdef CONFIG_STRICT_KERNEL_RWX
 static void mark_readonly(void)
 {
-- 
1.8.3.1

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