Why does Red Hat and Fedora software not distinguish between AMD and Intel kernels?

[Josh Boyer]

On Fri, Feb 7, 2014 at 10:01 AM, James Harrison
<jamesaharrisonuk at yahoo.co.uk> wrote:
> Hi.
> Thanks for the quick reply.
>
> So what architecture does Red Hat compile its kernels for? Having compiled the Linux Kernel, you must specify target architecture. Is there now a "general cpu" option?

Fedora builds for the i686 32-bit architecture, and the x86_64
architecture for 64-bit.  Those are the base 32-bit and 64-bit
architectures that both Intel and AMD processors support.  The
differences are in the microarchitecture, not the ISA.

> For specific CPU features like virtualisation flags, how do kernels know to report the correct CPU features? Is there a Red Hat patch?

CPU features and flags are detected at runtime by the upstream kernel.
 We don't carry any patches for that.

> Regarding the Ubuntu part of my email, Is there anyone out there who knows?

I have no idea.  Are they simply calling their 64-bit kernels "amd64"
instead of x86_64?  If so, that is purely a naming thing and they are
functionally equivalent on both Intel and AMD CPUs.

josh