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Peter Anvin" , Vitaly Kuznetsov , Kiryl Shutsemau , Rick Edgecombe , David Woodhouse , Paul Durrant Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On Thu, May 28, 2026, J=C3=BCrgen Gro=C3=9F wrote: > On 28.05.26 15:09, Sean Christopherson wrote: > > On Thu, May 28, 2026, Juergen Gross wrote: > > > Please disregard this series, there is one complication sashiko made = me > > > aware of. > >=20 > > Sashiko beat me to the punch. :-) > >=20 > > See commit 2368048bf5c2 ("KVM: x86: Signal #GP, not -EPERM, on bad WRMS= R(MCi_CTL/STATUS)") > > for a real world example of how things can and will go wrong. >=20 > Yeah, with Sashiko's pointer it was easy to spot. >=20 > Question now is whether the already existing cases of -errno passed as re= turn > value are wrong or on purpose.=20 What are the existing cases? > If the latter, there should be a comment for > that, otherwise they need to be fixed.. >=20 > Disentangling the MSR emulation return values from the "normal" ones ("re= turn > to guest"/"return to user mode") will be quite interesting with the overl= oaded > semantics of "1". LOL, "interesting".