watchdog: pretimeout: add panic pretimeout governor

The change adds panic watchdog pretimeout governor, on watchdog
pretimeout event the kernel shall panic. In general watchdog
pretimeout event means that something essentially bad is going on the
system, for example a process scheduler stalls or watchdog feeder is
killed due to OOM, so printing out information attendant to panic and
before likely unavoidable reboot caused by a watchdog may help to
determine a root cause of the issue.

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

1 files changed, 14 insertions, 0 deletions

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 4aeb8f95beb4..cbd33321c0f8 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -1856,6 +1856,14 @@ config WATCHDOG_PRETIMEOUT_DEFAULT_GOV_NOOP
           governor is selected by a user, write a short message to
           the kernel log buffer and don't do any system changes.
 
+config WATCHDOG_PRETIMEOUT_DEFAULT_GOV_PANIC
+        bool "panic"
+        select WATCHDOG_PRETIMEOUT_GOV_PANIC
+        help
+          Use panic watchdog pretimeout governor by default, if
+          a watchdog pretimeout event happens, consider that
+          a watchdog feeder is dead and reboot is unavoidable.
+
 endchoice
 
 config WATCHDOG_PRETIMEOUT_GOV_NOOP
@@ -1864,6 +1872,12 @@ config WATCHDOG_PRETIMEOUT_GOV_NOOP
           Noop watchdog pretimeout governor, only an informational
           message is added to kernel log buffer.
 
+config WATCHDOG_PRETIMEOUT_GOV_PANIC
+        tristate "Panic watchdog pretimeout governor"
+        help
+          Panic watchdog pretimeout governor, on watchdog pretimeout
+          event put the kernel into panic.
+
 endif # WATCHDOG_PRETIMEOUT_GOV
 
 endif # WATCHDOG