Re: [PATCH v2 0/3] x86/mm: INVPCID support

From: Ingo Molnar
Date: Mon Jan 25 2016 - 13:57:20 EST



* Andy Lutomirski <luto@xxxxxxxxxx> wrote:

> Ingo, before applying this, please apply these two KASAN fixes:
>
> http://lkml.kernel.org/g/1452516679-32040-2-git-send-email-aryabinin@xxxxxxxxxxxxx
> http://lkml.kernel.org/g/1452516679-32040-3-git-send-email-aryabinin@xxxxxxxxxxxxx
>
> Without those fixes, this series will trigger a KASAN bug.
>
> This is a straightforward speedup on Ivy Bridge and newer, IIRC.
> (I tested on Skylake. INVPCID is not available on Sandy Bridge.
> I don't have Ivy Bridge, Haswell or Broadwell to test on, so I
> could be wrong as to when the feature was introduced.)
>
> I think we should consider these patches separately from the rest
> of the PCID stuff -- they barely interact, and this part is much
> simpler and is useful on its own.
>
> This is exactly identical to patches 2-4 of the PCID RFC series.
>
> Andy Lutomirski (3):
> x86/mm: Add INVPCID helpers
> x86/mm: Add a noinvpcid option to turn off INVPCID
> x86/mm: If INVPCID is available, use it to flush global mappings
>
> Documentation/kernel-parameters.txt | 2 ++
> arch/x86/include/asm/tlbflush.h | 50 +++++++++++++++++++++++++++++++++++++
> arch/x86/kernel/cpu/common.c | 16 ++++++++++++
> 3 files changed, 68 insertions(+)

Ok, I'll pick these up tomorrow unless there are objections.

Thanks,

Ingo