Re: Machine crashes right *after* ~successful resume

[Yinghai Lu]

On Thu, Oct 16, 2014 at 2:08 PM, Wilmer van der Gaast <wilmer@xxxxxxxxx> wrote:
> Did that on this run, no difference either. For full completeness, I
> reproduced this problem with no modules loaded (done from initramfs) at all,
> with a kernel with your workaround included, logs are here:
> http://gaast.net/~wilmer/.lkml/bad3.17-patched-debug-initramfs.txt

Yes, those output are good.

Please apply attached debug patch on top of v3.17 and boot with
"debug ignore_loglevel initcall_debug no_console_suspend".

Hope we can find out which nb notifier cause problem.

Thanks

Yinghai
---
 kernel/notifier.c   |    9 +++++++++
 kernel/power/main.c |    4 +++-
 2 files changed, 12 insertions(+), 1 deletion(-)

Index: linux-2.6/kernel/power/main.c
===================================================================
--- linux-2.6.orig/kernel/power/main.c
+++ linux-2.6/kernel/power/main.c
@@ -24,16 +24,18 @@ DEFINE_MUTEX(pm_mutex);
 
 /* Routines for PM-transition notifications */
 
-static BLOCKING_NOTIFIER_HEAD(pm_chain_head);
+BLOCKING_NOTIFIER_HEAD(pm_chain_head);
 
 int register_pm_notifier(struct notifier_block *nb)
 {
+	pr_info("PM: registering nb %pF\n", nb->notifier_call);
 	return blocking_notifier_chain_register(&pm_chain_head, nb);
 }
 EXPORT_SYMBOL_GPL(register_pm_notifier);
 
 int unregister_pm_notifier(struct notifier_block *nb)
 {
+	pr_info("PM: unregistering nb %pF\n", nb->notifier_call);
 	return blocking_notifier_chain_unregister(&pm_chain_head, nb);
 }
 EXPORT_SYMBOL_GPL(unregister_pm_notifier);
Index: linux-2.6/kernel/notifier.c
===================================================================
--- linux-2.6.orig/kernel/notifier.c
+++ linux-2.6/kernel/notifier.c
@@ -59,6 +59,9 @@ static int notifier_chain_unregister(str
 	return -ENOENT;
 }
 
+extern struct blocking_notifier_head pm_chain_head;
+#define PM_POST_SUSPEND		0x0004 /* Suspend finished */
+
 /**
  * notifier_call_chain - Informs the registered notifiers about an event.
  *	@nl:		Pointer to head of the blocking notifier chain
@@ -90,8 +93,14 @@ static int notifier_call_chain(struct no
 			continue;
 		}
 #endif
+		if (nl == &pm_chain_head.head && val == PM_POST_SUSPEND)
+			pr_info("PM: calling nb %pF\n", nb->notifier_call);
+
 		ret = nb->notifier_call(nb, val, v);
 
+		if (nl == &pm_chain_head.head && val == PM_POST_SUSPEND)
+			pr_info("PM: ... nb %pF done\n", nb->notifier_call);
+
 		if (nr_calls)
 			(*nr_calls)++;