diff options
| author | John Ogness <john.ogness@linutronix.de> | 2024-02-07 14:47:03 +0106 |
|---|---|---|
| committer | Petr Mladek <pmladek@suse.com> | 2024-02-07 17:23:19 +0100 |
| commit | 7412dc6d55eed6b76180e40ac3601412ebde29bd (patch) | |
| tree | 3cb98e9f442a2c06d0d8005248a3a9841730d5e7 /include/linux/printk.h | |
| parent | d988d9a9b9d180bfd5c1d353b3b176cb90d6861b (diff) | |
dump_stack: Do not get cpu_sync for panic CPU
dump_stack() is called in panic(). If for some reason another CPU
is holding the printk_cpu_sync and is unable to release it, the
panic CPU will be unable to continue and print the stacktrace.
Since non-panic CPUs are not allowed to store new printk messages
anyway, there is no need to synchronize the stacktrace output in
a panic situation.
For the panic CPU, do not get the printk_cpu_sync because it is
not needed and avoids a potential deadlock scenario in panic().
Link: https://lore.kernel.org/lkml/ZcIGKU8sxti38Kok@alley
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20240207134103.1357162-15-john.ogness@linutronix.de
Signed-off-by: Petr Mladek <pmladek@suse.com>
Diffstat (limited to 'include/linux/printk.h')
| -rw-r--r-- | include/linux/printk.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/linux/printk.h b/include/linux/printk.h index 8ef499ab3c1e..955e31860095 100644 --- a/include/linux/printk.h +++ b/include/linux/printk.h @@ -273,6 +273,8 @@ static inline void printk_trigger_flush(void) } #endif +bool this_cpu_in_panic(void); + #ifdef CONFIG_SMP extern int __printk_cpu_sync_try_get(void); extern void __printk_cpu_sync_wait(void); |