From bc09d1dea84efaff022c09b9c5175b2a75553006 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= <u.kleine-koenig@pengutronix.de>
Date: Tue, 19 Dec 2023 19:28:09 +0100
Subject: [PATCH] lib: add note about process exit message for
 DEBUG_STACK_USAGE
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DEBUG_STACK_USAGE doesn't only have an influence on the output of sysrq-T
and sysrq-P, it also enables a message at process exit.  See
check_stack_usage() in kernel/exit.c where this is implemented.

Link: https://lkml.kernel.org/r/20231219182808.210284-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Kees Cook <keescook@chromium.org>
Cc: Marco Elver <elver@google.com>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 lib/Kconfig.debug | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index e77873cf85c7..6cc3d29338c5 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -763,6 +763,8 @@ config DEBUG_STACK_USAGE
 	help
 	  Enables the display of the minimum amount of free stack which each
 	  task has ever had available in the sysrq-T and sysrq-P debug output.
+	  Also emits a message to dmesg when a process exits if that process
+	  used more stack space than previously exiting processes.
 
 	  This option will slow down process creation somewhat.