Re: [PATCH] x86/idt: Unbreak MS HyperV hypercall vector install

[Stephen Hemminger]

On Fri, 8 Sep 2017 01:19:52 -0700
"Thomas Gleixner" <tglx@xxxxxxxxxxxxx> wrote:

> The rework of the IDT setup changed the way how unused system gates are
> accounted. At the end of the gate initialization all unused gates in the
> system vector area are set to the spurios handler and marked as used for
> consistency reasons.
> 
> Marking them as used breaks MS HyperV because it installs its hypercall
> vector after that point and the installation is guarded by the bit in the
> used_vectors map. So the hyperv vector stays directed to the spurious
> interrupt handler.
> 
> Leave them marked as unused again and unbreak HyperV that way.
> 
> Fixes: dc20b2d52653 ("x86/idt: Move interrupt gate initialization to IDT
> code")
> Reported-by: Stephen Hemminger <sthemmin@xxxxxxxxxxxxx>
> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

This fixes it, thanks.

Tested-by: Stephen Hemminger <sthemmin@xxxxxxxxxxxxx>