User-Agent:       Mozilla/5.0 (X11; Linux x86_64; rv:51.0) Gecko/20100101
Firefox/51.0
Build Identifier: 

After 2 rounds of a memtest86 run from a systemrescuecd 4.9.2, and
disconnecting an USB DVD drive, the next boot ended up in a kernel panic. The
panic happened during the boot process, possibly at the very beginning of it. 
As far as my memory serves, this might have been not the first time it happened
in similar circumstances. 

Reproducible: Sometimes

Steps to Reproduce:
1. Start a memtest86 from SystemrescueCD 4.9.2 from a DVD
2. Wait for at least one full round (~1h),
3. stop the test, disconnect the DVD drive,
4. Boot and pray. 
Actual Results:  
Kernel panics.

Expected Results:  
Machine boots successfully. 

Kernel version: 4.9.6-1-default #1 SMP PREEMPT Thu Jan 26 09:09:16 UTC 2017
(d1207ac)
Grub: 2.02~beta3-17.2

Machine: Latitude E7470 with i7-6600U, 8GiB RAM and 512GB SanDisk X400 M.2.