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Bae" , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, pbonzini@redhat.com, stable@vger.kernel.org, Zhao Liu , Binbin Wu Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On Tue, Aug 18, 2026, Christian Ludloff wrote: > On Tue, Aug 18, 2026 at 5:55=E2=80=AFPM Dave Hansen wrote: > > On 7/24/26 08:37, Christian Ludloff wrote: > > >> My understanding is that the revert was considered because TF32 neve= r > > >> reached any implementation. If that's incorrect, I'd certainly welco= me a > > >> correction. > > > Both TF32 and TRANSPOSE made it into a product that shipped. > > > > > > Not from Intel... but. > > > > > > So their CPUID feature flags and their opcodes aren't reclaimable > > > and efforts to rip out their software support are counterproductive. > > > > What would folks' preference be on how Intel should document this going > > forward? Just leave it as it as enumerating TF32? > > > > There are notes in the SDM like: > > > > Intel=C2=AE MPX has been deprecated and will not be available o= n any > > future processors. > > > > There could be a note like that for the TF32, I would imagine. >=20 > Yes, that terse sentence works. > Once for AMX-TRANSPOSE. > Once for AMX-TF32. Maybe use a similar approach as is done for the HYPERVISOR bit (0x1.ECX[31)= , and have the "Field Name" entry say Not Used, and then use the "Description" to= explain why? E.g. Register Field Name Description D= omain EAX[6] Not Used Intel processors always return 0. P= latform Allocated for backwards compatibility with software that expects this to enumerate AMX_TF32. Or Christian's terse version (I kinda like the terse version). Register Field Name Description D= omain EAX[6] Not Used Intel processors always return 0. P= latform Once for AMX_TF32. =20 > If you want the back references: > TRANSPOSE got dropped from ISE #059 and APX #007. > TF32 got dropped from ISE #062. >=20 > In terms of the opcodes, it is like MPX too: no recycling for > a long time. Luckily there is plenty of remaining space. >=20 > -- > C.