Re: [PATCH] add tlbi=off to disable INVLPGB

[Peter Zijlstra]

On Thu, Jul 30, 2026 at 09:23:18AM -0700, Borislav Petkov wrote:
> On Thu, Jul 30, 2026 at 12:32:27PM +0200, Peter Zijlstra wrote:
> > TLBI stands for Translation Lookaside Buffer Invalidation.
> 
> ... instructions." Both ARM and AMD call it this. The usual abbreviation
> overload we're suffering from.

Same difference, that would mean disabling all TLB instructions :-) Very
much including the local invalidation used for IPI based TLB
invalidation.

But also, nah:

  https://support.arm.com/documentation/dui0802/b/A64-General-Instructions/TLBI

"TLBI - TLB invalidate operation."
  
> > So a command line that says: 'tlbi=off' means no move invalidation *at*all*.
> > This seems like a very bad option.
> > 
> > Please rename.
> 
> You suggest one. :-P
> 
> But it needs to be short and relatively easy to type. And "invlpgb" ain't easy
> and I can't tell you how many times I've seen it getting typoed.

  tlbi={ipi,broadcast}

Anyway, INVLPGB stands for INVaLidate PaGe Broadcast, ain'ted that hard
:-) Also, you know who to complain to for that instruction :-)