Re: [PATCH 4.9 43/92] x86/pti: Do not enable PTI on CPUs which are not vulnerable to Meltdown

[Nick Lowe]

Hi,

This does not seem to have subsumed the AMD specific code in

x86/pti: Do not enable PTI on CPUs which are not vulnerable to Meltdown
Commit a8799fd14d9f7f385a5a5c86cde247caf4bb0320

https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/commit/?h=v4.9.81&id=a8799fd14d9f7f385a5a5c86cde247caf4bb0320

x86/kaiser: Check boottime cmdline params
Commit 8018307a45a90ab2eecfd03d48b7efb31707df37

https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/commit/arch/x86/mm/kaiser.c?h=v4.9.75&id=8018307a45a90ab2eecfd03d48b7efb31707df37

Here, we can see:

+skip:
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
+ goto disable;

Refer to 4.9.81's kaiser.c
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/tree/arch/x86/mm/kaiser.c?h=v4.9.81

Also 4.4.115's kaiser.c
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/tree/arch/x86/mm/kaiser.c?h=v4.4.115

Cheers,

Nick