Re: [PATCH v3 5/6] x86/pti: Do not enable PTI on processors which are not vulnerable to Meltdown

From: Greg KH
Date: Wed Jan 24 2018 - 12:26:51 EST


On Wed, Jan 24, 2018 at 04:57:04PM +0000, David Woodhouse wrote:
> Some old Atoms, anything in family 5 or 4, and newer CPUs when they advertise
> the IA32_ARCH_CAPABILITIES MSR and it has the RDCL_NO bit set, are not vulnerable.
>
> Roll the AMD exemption into the x86_match_cpu() table too.
>
> Based on suggestions from Dave Hansen and Alan Cox.
>
> Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx>

Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>