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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.56.2 (3.56.2-2.fc42) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Fri, 2026-07-31 at 10:46 +0200, Peter Zijlstra wrote: > On Thu, Jul 30, 2026 at 11:24:39AM -0700, Borislav Petkov wrote: >=20 > >=20 > > We probably won't need to write "bcast" at all, actually, because > > that would > > be the default. So "tlbi=3Dipi" only. Yeah, that's good. >=20 > Didn't we have a case where INVLPGB was disabled due to firmware or > something? I was thinking tlbi=3Dbroadcast could be used to force > enable > it or something. I have a mini PC here that does just that. lspcu says: AMD Ryzen 9 7940HS w/ Radeon 780M Graphics That suggests the core should have INVLPGB built-in, but it shows up as disabled in cpuid. $ cpuid -1 | grep INVLPGB INVLPGB instruction =3D false INVLPGB supports TLB flush guest nested =3D false max page count for INVLPGB instruction =3D 0x0 (0) INVLPGB/TLBSYNC hyperv interc enable =3D false I have not been able to find a BIOS option that results in it being enabled. --=20 All Rights Reversed.