Re: [4.22] Re: [PATCH] x86/domctl: restore all registers in arch_{get,set}_info_guest()

On Mon, 20 Jul 2026 at 10:09, Andrew Cooper <[email protected]> wrote:
>
> On 20/07/2026 8:19 am, Jan Beulich wrote:
> > On 20.07.2026 02:12, Marek Marczykowski-Górecki wrote:
> >> Commit 9f892f84c279 ("x86/domctl: Stop using XLAT_cpu_user_regs()")
> >> converted memcpy() of the cpu_user_regs structure to explicit copy of
> >> its fields. In the compat case, it intentionally missed few of them,
> >> named in the commit message. But the 64bit case missed also r8-r15
> >> registers, which was not intentional. This, at least, caused Linux
> >> 6.18.x crash when resuming PVH domU.
> > Oh, wow, what a bad mistake (including by me as the reviewer).
>
> Yes, I'm very embarrassed by this mistake.  It also highlights a serious
> gap in testing which we need to address.  We've managed a release and a
> half with PV migration plain broken before figuring out why.
>
...

Is migration tested by CI or just for some reason this was not captured?

Frediano