From: Ingo Molnar Date: Thu, 7 Dec 2006 04:40:51 +0000 (-0800) Subject: [PATCH] add ignore_loglevel boot option X-Git-Tag: v2.6.20-rc1~145^2^2~34 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=792908225064b1d841a8990b9d1d1cfc4e0e5bb2;p=linux-2.6 [PATCH] add ignore_loglevel boot option Sometimes the kernel prints something interesting while userspace bootup keeps messages turned off via loglevel. Enable the printing of /all/ kernel messages via the "ignore_loglevel" boot option. Off by default. Signed-off-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 2a40d9f6ff..6b3c3e37a2 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -650,6 +650,10 @@ and is between 256 and 4096 characters. It is defined in the file idle= [HW] Format: idle=poll or idle=halt + ignore_loglevel [KNL] + Ignore loglevel setting - this will print /all/ + kernel messages to the console. Useful for debugging. + ihash_entries= [KNL] Set number of hash buckets for inode cache. diff --git a/kernel/printk.c b/kernel/printk.c index c3d90a58e4..185bb45eac 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -333,13 +333,25 @@ static void __call_console_drivers(unsigned long start, unsigned long end) } } +static int __read_mostly ignore_loglevel; + +int __init ignore_loglevel_setup(char *str) +{ + ignore_loglevel = 1; + printk(KERN_INFO "debug: ignoring loglevel setting.\n"); + + return 1; +} + +__setup("ignore_loglevel", ignore_loglevel_setup); + /* * Write out chars from start to end - 1 inclusive */ static void _call_console_drivers(unsigned long start, unsigned long end, int msg_log_level) { - if (msg_log_level < console_loglevel && + if ((msg_log_level < console_loglevel || ignore_loglevel) && console_drivers && start != end) { if ((start & LOG_BUF_MASK) > (end & LOG_BUF_MASK)) { /* wrapped write */