Commit 3a9f84d3 authored Jan 26, 2009 by Ed Swierk Committed by Ingo Molnar Jan 27, 2009

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>

parent bf50c903

kernel/signal.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -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)

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