From: Steven Rostedt (VMware) <[email protected]>
There's been discussion on the fb list about the addition of WARN_CONSOLE_UNLOCKED() inside the fb code. The complaint is that when the fb module is loaded with lockless_register_fb the console lock is not taken for debugging reasons. With the addition of WARN_CONSOLE_UNLOCK() within the fb code, this causes the console to fill up with warnings when trying to debug the fb driver. There's also a #if 1 that enables the warning which was added before git history, and we look down on constant #if's in the kernel nowadays anyway. Remove the #if 1 and add a ignore_console_lock_warning boolean that can be set by drivers to ignore the warning in order to do debugging. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Steven Rostedt (VMware) <[email protected]> --- diff --git a/include/linux/console.h b/include/linux/console.h index dfd6b0e97855..9d4a6b985154 100644 --- a/include/linux/console.h +++ b/include/linux/console.h @@ -200,11 +200,9 @@ void vcs_make_sysfs(int index); void vcs_remove_sysfs(int index); /* Some debug stub to catch some of the obvious races in the VT code */ -#if 1 -#define WARN_CONSOLE_UNLOCKED() WARN_ON(!is_console_locked() && !oops_in_progress) -#else -#define WARN_CONSOLE_UNLOCKED() -#endif +extern bool ignore_console_lock_warning; +#define WARN_CONSOLE_UNLOCKED() \ + WARN_ON(!ignore_console_lock_warning && !is_console_locked() && !oops_in_progress) /* VESA Blanking Levels */ #define VESA_NO_BLANKING 0 diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 247808333ba4..d9056efc3739 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -66,6 +66,9 @@ int console_printk[4] = { CONSOLE_LOGLEVEL_DEFAULT, /* default_console_loglevel */ }; +bool ignore_console_lock_warning __read_mostly; +EXPORT_SYMBOL(ignore_console_lock_warning); + /* * Low level drivers may need that to know if they can schedule in * their unblank() callback or not. So let's export it.
