Created attachment 196111 [details]
config of affected 4.4-rc2 kernel

I think this may more be related to control groups, but I didn´t find them product list.

Crash happens on ThinkPad T520 on boot since 4.4-rc2. With 4.4-rc2 I have been able to boot once and use this boot session via hibernation for some days. 4.4-rc3 didn´t boot at all in more than 5 attempts. This crash does not happen with 4.3.

martin@merkaba:~> phoronix-test-suite system-info

Phoronix Test Suite v5.2.1
System Information

Hardware:
Processor: Intel Core i5-2520M @ 3.20GHz (4 Cores), Motherboard: LENOVO 42433WG, Chipset: Intel 2nd Generation Core Family DRAM, Memory: 16384MB, Disk: 300GB INTEL SSDSA2CW30 + 480GB Crucial_CT480M50, Graphics: Intel HD 3000 (1300MHz), Audio: Conexant CX20590, Network: Intel 82579LM Gigabit Connection + Intel Centrino Advanced-N 6205

Software:
OS: Debian unstable, Kernel: 4.3.0-tp520-btrfstrim+ (x86_64), Desktop: KDE Frameworks 5, Display Server: X Server 1.17.3, Display Driver: intel 2.99.917, OpenGL: 3.3 Mesa 11.0.6, Compiler: GCC 5.2.1 20151125, File-System: btrfs, Screen Resolution: 1920x1080

I will attach some I bet incomplete screenshots of the traces and the kernel configuration in use. I will also attach configuration of 4.3 kernel which doesn´t show this crash.

This is mainline kernel with a little fix for BTRFS SSD trimming.

martin@merkaba:~> cat /proc/version
Linux version 4.3.0-tp520-btrfstrim+ (martin@merkaba) (gcc version 5.2.1 20151028 (Debian 5.2.1-23) ) #43 SMP PREEMPT Mon Nov 2 10:43:19 CET 2015

I do not want to spent the time and risk of bisecting this issue on this production machine. I am open for other suggestions to pin-point the cause.

I mentioned this already on LKML:

Subject	[4.4-rc2] regresstion: ksoftirqd/2 Fatal exception in interrupt pids.freepids.uncharge.constprop
Date	Sat, 28 Nov 2015 12:38:46 +0100

https://lkml.org/lkml/2015/11/28/36

Thanks, Martin