signals, debug: fix BUG: using smp_processor_id() in preemptible code in print_fatal_signal()

With print-fatal-signals=1 on a kernel with CONFIG_PREEMPT=y, sending an
unexpected signal to a process causes a BUG: using smp_processor_id() in
preemptible code.

get_signal_to_deliver() releases the siglock before calling
print_fatal_signal(), which calls show_regs(), which calls
smp_processor_id(), which is not supposed to be called from a
preemptible thread.

Make sure show_regs() runs with preemption disabled.

Signed-off-by: Ed Swierk <eswierk@aristanetworks.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Ed Swierk 2009-01-26 15:33:31 -08:00 committed by Ingo Molnar
parent bf50c903fa
commit 3a9f84d354

View File

@ -909,7 +909,9 @@ static void print_fatal_signal(struct pt_regs *regs, int signr)
}
#endif
printk("\n");
preempt_disable();
show_regs(regs);
preempt_enable();
}
static int __init setup_print_fatal_signals(char *str)