[PATCH 2/4] panic: use the aural error reporting framework to report panics

[Matteo Croce]

Use the new aural error reporting framework to signal kernel panic. The
error sound is emitted between the stack dump and the kexec jump.

Signed-off-by: Matteo Croce <mcr...@redhat.com>
---
 kernel/panic.c    | 25 +++++++++++++++++++++++++
 lib/Kconfig.debug | 10 ++++++++++
 2 files changed, 35 insertions(+)

diff --git a/kernel/panic.c b/kernel/panic.c
index 0ae0d7332f12..360578e092e7 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -29,6 +29,7 @@
 #include <linux/bug.h>
 #include <linux/ratelimit.h>
 #include <linux/debugfs.h>
+#include <linux/play.h>
 #include <asm/sections.h>
 
 #define PANIC_TIMER_STEP 100
@@ -57,6 +58,29 @@ ATOMIC_NOTIFIER_HEAD(panic_notifier_list);
 
 EXPORT_SYMBOL(panic_notifier_list);
 
+#ifdef CONFIG_AUDIBLE_PANIC
+static struct note panic_sound[] = {
+       { 784, 400 },
+       { 784, 400 },
+       { 784, 400 },
+       { 622, 300 },
+       { 932, 100 },
+       { 784, 400 },
+       { 622, 300 },
+       { 932, 100 },
+       { 784, 800 },
+       { 1174, 400 },
+       { 1174, 400 },
+       { 1174, 400 },
+       { 1244, 300 },
+       { 932, 100 },
+       { 740, 400 },
+       { 622, 300 },
+       { 932, 100 },
+       { 784, 800 },
+};
+#endif
+
 static long no_blink(int state)
 {
        return 0;
@@ -213,6 +237,7 @@ void panic(const char *fmt, ...)
        if (!test_taint(TAINT_DIE) && oops_in_progress <= 1)
                dump_stack();
 #endif
+       play(panic_sound, ARRAY_SIZE(panic_sound));
 
        /*
         * If we have crashed and we have a crash kernel loaded let it handle
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 10d04b266aef..e5d187dfc74a 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -997,6 +997,16 @@ config PLAY_LIB
        depends on HAVE_PCSPKR_PLATFORM
        default n
 
+config AUDIBLE_PANIC
+       bool "Aural panic"
+       select PLAY_LIB
+       default n
+       help
+         If you say Y here, kernel panics will play a sound just
+         after the stacktrace and registers dump. The sound is played via
+         the system buzzer and not via any soundcard.
+         Not available on all platforms.
+
 config SCHED_DEBUG
        bool "Collect scheduler debugging info"
        depends on DEBUG_KERNEL && PROC_FS
-- 
2.20.1