Merge pull request #9918 from SvenDowideit/state-centos-kernel-restrictions-clearly

Centos project does not support custom kernels

docs/sources/installation/centos.md

@@ -27,6 +27,13 @@ simply run the following command.
 
     $ sudo yum install docker
 
+## Kernel support
+
+Currently the CentOS project will only support Docker via the EPEL package when
+running on kernels shipped by the distribution. There are things like namespace
+changes which will cause issues if one decides to step outside that box and run
+non-distro kernel packages.
+
 ### Manual installation of latest version
 
 While using a package is the recommended way of installing Docker,

docs/sources/installation/rhel.md

@@ -40,6 +40,13 @@ You will need [RHEL
 a RHEL 6 kernel version 2.6.32-431 or higher as this has specific kernel
 fixes to allow Docker to work.
 
+## Kernel support
+
+RHEL will only support Docker via the *extras* channel or EPEL package when
+running on kernels shipped by the distribution. There are things like namespace
+changes which will cause issues if one decides to step outside that box and run
+non-distro kernel packages.
+
 ## Installation
 
 Firstly, you need to install the EPEL repository. Please follow the