Re: [Xen-devel] [PATCH 00/13] x86/paravirt: Make pv ops code generation more closely match reality

[Josh Poimboeuf]

On Fri, Oct 06, 2017 at 09:35:16AM +0200, Vitaly Kuznetsov wrote:
> Josh Poimboeuf <jpoimboe@xxxxxxxxxx> writes:
> 
> > - For the most common runtime cases (everything except Xen and vSMP),
> >   vmlinux disassembly now matches what the actual runtime code looks
> >   like.  This improves debuggability and kernel developer sanity (a
> >   precious resource).
> >
> > ...
> >
> > - It's hopefully a first step in simplifying paravirt patching by
> >   getting rid of .parainstructions, pv ops, and apply_paravirt()
> >   completely.  (I think Xen can be changed to set CPU feature bits to
> >   specify which ops it needs during early boot, then those ops can be
> >   patched in using early alternatives.)
> 
> JFYI starting 4.14 Xen PV is not the only user of pv_mmu_ops, Hyper-V
> uses it for TLB shootdown now.

Yeah, I saw that.  It should be fine because the pv_alternatives get
patched before the Hyper-V code sets up pv_mmu_ops.

-- 
Josh