#include <linux/kernel.h> #include <linux/init.h> #include <linux/console.h> #include "chan_user.h" /* ----------------------------------------------------------------------------- */ /* trivial console driver -- simply dump everything to stderr */ /* * Don't register by default -- as this registeres very early in the * boot process it becomes the default console. * * Initialized at init time. */ static int use_stderr_console = 0; static void stderr_console_write(struct console *console, const char *string, unsigned len) { generic_write(2 /* stderr */, string, len, NULL); } static struct console stderr_console = { .name = "stderr", .write = stderr_console_write, .flags = CON_PRINTBUFFER, }; static int __init stderr_console_init(void) { if (use_stderr_console) register_console(&stderr_console); return 0; } console_initcall(stderr_console_init); static int stderr_setup(char *str) { if (!str) return 0; use_stderr_console = simple_strtoul(str,&str,0); return 1; } __setup("stderr=", stderr_setup); /* The previous behavior of not unregistering led to /dev/console being * impossible to open. My FC5 filesystem started having init die, and the * system panicing because of this. Unregistering causes the real * console to become the default console, and /dev/console can then be * opened. Making this an initcall makes this happen late enough that * there is no added value in dumping everything to stderr, and the * normal console is good enough to show you all available output. */ static int __init unregister_stderr(void) { unregister_console(&stderr_console); return 0; } __initcall(unregister_stderr);