Created attachment 1202961 [details]
system log of instance that won't boot

Description of problem:

AMI RHEL-7.3_HVM_Beta-20160819-x86_64 will not boot because of "Kernel panic - not syncing: Fatal exception". 

The problem only occurs with two instance types:
m3.large
c3.large

I gave it a try in four regions, the results were the same in all of them, wherever I used either m3.large or c3.large, the instance wouldn't boot.

How reproducible:
always

Steps to Reproduce:
1. Launch an instance of ami-5dff9c4a in US East region, select either m3.large or c3.large as Instance Type.
2. The instance won't pass internal Status Checks and will not be reachable. 
3. The system log says kernel panic, see attached log file.

Actual results:
The instance fails to boot.

Expected results:
The instance boots as normal.