tree 3cb98e9f442a2c06d0d8005248a3a9841730d5e7
parent d988d9a9b9d180bfd5c1d353b3b176cb90d6861b
author John Ogness <john.ogness@linutronix.de> 1707313263 +0106
committer Petr Mladek <pmladek@suse.com> 1707322999 +0100

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>