On Sat, 12 May 2007 11:18:09 +0200 Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote: > > It's peculiar that the hang happens when acpi_evaluate_object() hits its > > return statement. Any theories there? > > Only stack or memory corruption come into mind, but I have no clue how > this is related to the resume logic changes. So I had the brilliant idea of turning on some kernel debugging. It's a shame that CONFIG_SOFTWARE_SUSPEND disables CONFIG_DEBUG_PAGEALLOC. [ 73.533454] swsusp: Basic memory bitmaps created [ 73.550429] Stopping tasks ... BUG: at kernel/lockdep.c:2414 check_flags() [ 73.550988] [<c0104c14>] show_trace_log_lvl+0x1a/0x30 [ 73.551143] [<c0105769>] show_trace+0x12/0x14 [ 73.551279] [<c01057c1>] dump_stack+0x15/0x17 [ 73.551412] [<c0132732>] check_flags+0x93/0x13d [ 73.551554] [<c0135558>] lock_acquire+0x28/0x7f [ 73.551691] [<c0310e35>] _spin_lock+0x2b/0x38 [ 73.551827] [<c013dc43>] refrigerator+0x16/0xc7 [ 73.551965] [<c0125d2e>] get_signal_to_deliver+0x32/0x387 [ 73.552124] [<c010336d>] do_notify_resume+0x91/0x6a9 [ 73.552271] [<c0103df1>] work_notifysig+0x13/0x1a [ 73.552413] ======================= [ 73.552507] irq event stamp: 3075 [ 73.552595] hardirqs last enabled at (3075): [<c0103e51>] syscall_exit_work+0x11/0x26 [ 73.552821] hardirqs last disabled at (3074): [<c0103d35>] syscall_exit+0x9/0x1a [ 73.553046] softirqs last enabled at (2778): [<c01209f2>] __do_softirq+0x92/0x9a [ 73.553255] softirqs last disabled at (2693): [<c0120a27>] do_softirq+0x2d/0x46 [ 73.559504] done. [ 73.559569] Shrinking memory... -done (0 pages freed) [ 73.646511] Freed 0 kbytes in 0.08 seconds (0.00 MB/s) [ 73.649595] platform sonypi: freeze [ 73.649707] platform bluetooth: freeze [ 73.649817] usb_endpoint usbdev5.1_ep81: PM: suspend 0->1, parent 5-0:1.0 already 2 [ 73.650023] hub 5-0:1.0: PM: suspend 2-->1 <snippage> [ 73.739499] ipw2200 0000:06:0b.0: freeze [ 73.743860] eth1: Going into suspend... [ 73.748444] e100 0000:06:08.0: freeze at this point I lost netconsole (earlier testing was without netconsole btw) The lockdep spew is coming out of here: static void check_flags(unsigned long flags) { #if defined(CONFIG_DEBUG_LOCKDEP) && defined(CONFIG_TRACE_IRQFLAGS) if (!debug_locks) return; if (irqs_disabled_flags(flags)) --> DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled); else DEBUG_LOCKS_WARN_ON(!current->hardirqs_enabled); and the callsite is: void refrigerator(void) { /* Hmm, should we be allowed to suspend when there are realtime processes around? */ long save; --> task_lock(current); if (freezing(current)) { frozen_process(); task_unlock(current); } else { I don't really know what lockdep is complaining about there. I assume I'm not supposed to, given that whoever wrote that couldn't be bothered documenting any of it. I _think_ it means that lockdep believes that local irqs are enabled (according to its state tracking), only it turns out that they're not. - To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html