diff options
| author | John Ogness <john.ogness@linutronix.de> | 2024-08-20 09:29:55 +0300 |
|---|---|---|
| committer | Petr Mladek <pmladek@suse.com> | 2024-08-21 15:56:25 +0300 |
| commit | e35a8884270bae11196eedf3b0a5bf22619f11f2 (patch) | |
| tree | cc81a846c28d8dea1f67f0c7ab275756d09d12d6 /include/linux | |
| parent | bebd87ae27e052e390c203893c7ee46f54b0bf9e (diff) | |
| download | linux-e35a8884270bae11196eedf3b0a5bf22619f11f2.tar.xz | |
printk: Coordinate direct printing in panic
If legacy and nbcon consoles are registered and the nbcon
consoles are allowed to flush (i.e. no boot consoles
registered), the legacy consoles will no longer perform
direct printing on the panic CPU until after the backtrace
has been stored. This will give the safe nbcon consoles a
chance to print the panic messages before allowing the
unsafe legacy consoles to print.
If no nbcon consoles are registered or they are not allowed
to flush because boot consoles are registered, there is no
change in behavior (i.e. legacy consoles will always attempt
to print from the printk() caller context).
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20240820063001.36405-30-john.ogness@linutronix.de
Signed-off-by: Petr Mladek <pmladek@suse.com>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/printk.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/include/linux/printk.h b/include/linux/printk.h index 2e083f01f8a3..eca9bb2ee637 100644 --- a/include/linux/printk.h +++ b/include/linux/printk.h @@ -200,6 +200,7 @@ extern asmlinkage void dump_stack_lvl(const char *log_lvl) __cold; extern asmlinkage void dump_stack(void) __cold; void printk_trigger_flush(void); void console_try_replay_all(void); +void printk_legacy_allow_panic_sync(void); extern bool nbcon_device_try_acquire(struct console *con); extern void nbcon_device_release(struct console *con); void nbcon_atomic_flush_unsafe(void); @@ -286,6 +287,10 @@ static inline void console_try_replay_all(void) { } +static inline void printk_legacy_allow_panic_sync(void) +{ +} + static inline bool nbcon_device_try_acquire(struct console *con) { return false; |