diff options
Diffstat (limited to 'kernel/printk')
-rw-r--r-- | kernel/printk/Makefile | 1 | ||||
-rw-r--r-- | kernel/printk/internal.h | 14 | ||||
-rw-r--r-- | kernel/printk/printk.c | 23 | ||||
-rw-r--r-- | kernel/printk/printk_safe.c | 14 |
4 files changed, 25 insertions, 27 deletions
diff --git a/kernel/printk/Makefile b/kernel/printk/Makefile index 4a2ffc39eb95..4d052fc6bcde 100644 --- a/kernel/printk/Makefile +++ b/kernel/printk/Makefile @@ -1,3 +1,4 @@ +# SPDX-License-Identifier: GPL-2.0-only obj-y = printk.o obj-$(CONFIG_PRINTK) += printk_safe.o obj-$(CONFIG_A11Y_BRAILLE_CONSOLE) += braille.o diff --git a/kernel/printk/internal.h b/kernel/printk/internal.h index 0f1898820cba..c8e6ab689d42 100644 --- a/kernel/printk/internal.h +++ b/kernel/printk/internal.h @@ -1,18 +1,6 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ /* * internal.h - printk internal definitions - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version 2 - * of the License, or (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, see <http://www.gnu.org/licenses/>. */ #include <linux/percpu.h> diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 02ca827b8fac..1888f6a3b694 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * linux/kernel/printk.c * @@ -86,6 +87,12 @@ static DEFINE_SEMAPHORE(console_sem); struct console *console_drivers; EXPORT_SYMBOL_GPL(console_drivers); +/* + * System may need to suppress printk message under certain + * circumstances, like after kernel panic happens. + */ +int __read_mostly suppress_printk; + #ifdef CONFIG_LOCKDEP static struct lockdep_map console_lock_dep_map = { .name = "console_lock" @@ -1943,6 +1950,10 @@ asmlinkage int vprintk_emit(int facility, int level, unsigned long flags; u64 curr_log_seq; + /* Suppress unimportant messages after panic happens */ + if (unlikely(suppress_printk)) + return 0; + if (level == LOGLEVEL_SCHED) { level = LOGLEVEL_DEFAULT; in_sched = true; @@ -2525,10 +2536,11 @@ void console_unblank(void) /** * console_flush_on_panic - flush console content on panic + * @mode: flush all messages in buffer or just the pending ones * * Immediately output all pending messages no matter what. */ -void console_flush_on_panic(void) +void console_flush_on_panic(enum con_flush_mode mode) { /* * If someone else is holding the console lock, trylock will fail @@ -2539,6 +2551,15 @@ void console_flush_on_panic(void) */ console_trylock(); console_may_schedule = 0; + + if (mode == CONSOLE_REPLAY_ALL) { + unsigned long flags; + + logbuf_lock_irqsave(flags); + console_seq = log_first_seq; + console_idx = log_first_idx; + logbuf_unlock_irqrestore(flags); + } console_unlock(); } diff --git a/kernel/printk/printk_safe.c b/kernel/printk/printk_safe.c index 0913b4d385de..b4045e782743 100644 --- a/kernel/printk/printk_safe.c +++ b/kernel/printk/printk_safe.c @@ -1,18 +1,6 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* * printk_safe.c - Safe printk for printk-deadlock-prone contexts - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version 2 - * of the License, or (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, see <http://www.gnu.org/licenses/>. */ #include <linux/preempt.h> |