Re: [RFC PATCH] x86/mm: Flush more aggressively in lazy TLB mode

[Borislav Petkov]

+ Johannes Hirte.

On Mon, Oct 09, 2017 at 09:50:49AM -0700, Andy Lutomirski wrote:
> Since commit 94b1b03b519b, x86's lazy TLB mode has been all the way

...

> There are two optimizations we should probably do on top of this.
> 
>  - In lazy mode, we should switch to init_mm when entering a long idle
>    state.  We used to do this, but it was a mess.  I'm working on a clean
>    patch to reinstate it.
> 
>  - In non-lazy mode with PCID, we could microoptimize switches to init_mm
>    by hardcoding the ASID.
> 
>  arch/x86/include/asm/mmu_context.h |   8 +-
>  arch/x86/include/asm/tlbflush.h    |  24 ++++++
>  arch/x86/mm/tlb.c                  | 153 +++++++++++++++++++++++++++----------
>  3 files changed, 136 insertions(+), 49 deletions(-)

I'm getting conflicts when trying to apply it ontop of rc4+tip/master but they
seem only contextual. Here's what applies:

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