From 4bff794a89e6457eb993efdf28add5adc54c7c67 Mon Sep 17 00:00:00 2001 Message-Id: <4bff794a89e6457eb993efdf28add5adc54c7c67.1588797587.git.zanussi@kernel.org> In-Reply-To: <94c546b56877133a33b6e344bfe3ee7f698d069a.1588797587.git.zanussi@kernel.org> References: <94c546b56877133a33b6e344bfe3ee7f698d069a.1588797587.git.zanussi@kernel.org> From: Peter Zijlstra Date: Fri, 2 Sep 2011 14:41:29 +0200 Subject: [PATCH 058/327] printk: Add "force_early_printk" boot param to help with debugging Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.120-rt52.tar.xz Gives me an option to screw printk and actually see what the machine says. Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/1314967289.1301.11.camel@twins Signed-off-by: Thomas Gleixner Link: http://lkml.kernel.org/n/tip-ykb97nsfmobq44xketrxs977@git.kernel.org --- kernel/printk/printk.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 29838e532f46..f934baed564d 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -435,6 +435,13 @@ asmlinkage void early_printk(const char *fmt, ...) */ static bool __read_mostly printk_killswitch; +static int __init force_early_printk_setup(char *str) +{ + printk_killswitch = true; + return 0; +} +early_param("force_early_printk", force_early_printk_setup); + void printk_kill(void) { printk_killswitch = true; -- 2.17.1