Bug 47741

Summary: After pressing SysRq+J (Emergency Thaw), system generates 5GB of log and DIES
Product: IO/Storage Reporter: kenorb (kenorb)
Component: Block LayerAssignee: Jens Axboe (axboe)
Status: RESOLVED CODE_FIX    
Severity: normal CC: alan, cobbsteven397, cordydaymen, edwardtricky123, intkecsk, jackmiller5623, jamesdeny665, jarvisdeny123, mat.jonczyk, michelmaxwell491, vi0oss
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: 3.5.0-10-generic Subsystem:
Regression: No Bisected commit-id:

Description kenorb 2012-09-20 07:56:09 UTC 
After pressing SysRq+J, kernel dumping the following error:
kernel: [160192.060834] Emergency Thaw on sda4
endless until the machine will die.
After 47,5mln of records and 4,5GB of log (around 80000 lines per second) within 12 minutes I had to do hard reboot.

My machine:
HP Compaq 8100 Elite

Related link:
http://superuser.com/questions/360360/what-is-sysrqj-thaw-frozen-filesystems

This sounds similar:
https://bugzilla.kernel.org/show_bug.cgi?id=12781
but probably it's something else.
Comment 2 _Vi 2012-09-20 12:29:20 UTC 
Trying some kernels I used in VirtualBox:

3.3.6-pf-vi+  : Reproducible
3.2.0-zen-vi+ : Reproducible
3.0.4-zen-vi+ : Reproducible
2.6.37.5-zen-... : Reproducible
2.6.33-zen2-... : Reproducible
2.6.32-zen1-... : Reproducible
2.6.31-zen11-... : Not reproducible
2.6.30-zen2-... : Not reproducible

Testing using "VBoxManage controlvm <vm_name> keyboardputscancode 1d 38 54  24 a4  d4 b8 9d"
Comment 4 Mateusz Jończyk 2015-02-26 18:44:57 UTC 
This bug is still present on kernel 3.13 amd64 (from Ubuntu Trusty).
Comment 5 Anton Sanarov 2016-01-19 12:56:38 UTC 
This bug is still present in 4.3.3 and 4.4.0