Re: [RFC/HACK] x86: Fast return to kernel

[Thomas Gleixner]

On Fri, 2 May 2014, Linus Torvalds wrote:

> On Fri, May 2, 2014 at 1:30 PM, Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote:
> >
> > So what about manipulating the stack so that the popf does not enable
> > interrupts and do an explicit sti to get the benefit of the
> > one-instruction shadow ?
> 
> That's what I already suggested in the original "I don't think popf
> works" email.

Missed that.
 
> It does get more complex since you now have to test things (there are
> very much cases where we get page faults and other exceptions with
> interrupts disabled), but it shouldn't be much worse.

Right. The extra conditional is probably not noticable at all.

Thanks,

	tglx
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