Messages in this thread | | | Date | Fri, 11 Mar 2016 12:08:18 -0800 | From | Andrew Morton <> | Subject | Re: [PATCH] kernel: panic: make panic() local lock raw |
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On Fri, 11 Mar 2016 18:48:25 +0100 Sebastian Andrzej Siewior <bigeasy@linutronix.de> wrote:
> The lock is taken with disabled interrupts and therefore it must be > a RAW lock. Otherwise -RT will convert it into a sleeping lock and > complain about it.
panic_lock doesn't exist in current kernels.
However you may want to take a look at pause_on_oops_lock - strange things are happening with IRQs there.
> --- a/kernel/panic.c > +++ b/kernel/panic.c > @@ -71,7 +71,7 @@ void __weak panic_smp_self_stop(void) > */ > void panic(const char *fmt, ...) > { > - static DEFINE_SPINLOCK(panic_lock); > + static DEFINE_RAW_SPINLOCK(panic_lock);
This should have had a comment explaining why a raw spinlock was chosen.
> static char buf[1024]; > va_list args; > long i, i_next = 0; > @@ -95,7 +95,7 @@ void panic(const char *fmt, ...) > * stop themself or will wait until they are stopped by the 1st CPU > * with smp_send_stop(). > */ > - if (!spin_trylock(&panic_lock)) > + if (!raw_spin_trylock(&panic_lock)) > panic_smp_self_stop(); > > console_verbose();
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