From: Christian Borntraeger When doing an magic sysrq reboot on s390 the following bug message appears: SysRq : Resetting BUG: sleeping function called from invalid context at include/asm/semaphore.h:61 in_atomic():1, irqs_disabled():0 07000000004002a8 000000000fe6bc48 0000000000000002 0000000000000000 000000000fe6bce8 000000000fe6bc60 000000000fe6bc60 000000000012a79a 0000000000000000 07000000004002a8 0000000000000006 0000000000000000 0000000000000000 000000000fe6bc48 000000000000000d 000000000fe6bcb8 00000000004000c8 0000000000103234 000000000fe6bc48 000000000fe6bc90 Call Trace: (¬<00000000001031b2>| show_trace+0x12e/0x148) ¬<000000000011ffca>| __might_sleep+0x10a/0x118 ¬<0000000000129fba>| acquire_console_sem+0x92/0xf4 ¬<000000000012a2ca>| console_unblank+0xc2/0xc8 ¬<0000000000107bb4>| machine_restart+0x54/0x6c ¬<000000000028e806>| sysrq_handle_reboot+0x26/0x30 ¬<000000000028e52a>| __handle_sysrq+0xa6/0x180 ¬<0000000000140134>| run_workqueue+0xcc/0x18c ¬<000000000014029a>| worker_thread+0xa6/0x108 ¬<00000000001458e4>| kthread+0x64/0x9c ¬<0000000000106f0e>| kernel_thread_starter+0x6/0xc ¬<0000000000106f08>| kernel_thread_starter+0x0/0xc The only reason for doing a console_unblank on s390 is to flush the log buffer. We have to check for in_atomic before doing a console_unblank as the console is otherwise filled with an unrelated bug message. Signed-off-by: Christian Borntraeger Signed-off-by: Martin Schwidefsky --- arch/s390/kernel/setup.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff -urpN linux-2.6/arch/s390/kernel/setup.c linux-2.6-patched/arch/s390/kernel/setup.c --- linux-2.6/arch/s390/kernel/setup.c 2007-10-09 22:31:38.000000000 +0200 +++ linux-2.6-patched/arch/s390/kernel/setup.c 2007-11-16 14:27:37.000000000 +0100 @@ -347,7 +347,7 @@ void (*_machine_power_off)(void) = do_ma void machine_restart(char *command) { - if (!in_interrupt() || oops_in_progress) + if ((!in_interrupt() && !in_atomic()) || oops_in_progress) /* * Only unblank the console if we are called in enabled * context or a bust_spinlocks cleared the way for us. -- blue skies, Martin. "Reality continues to ruin my life." - Calvin. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/