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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.54.3 (3.54.3-1.fc41) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Sender: riel@surriel.com On Wed, 2025-02-26 at 12:12 -0600, Tom Lendacky wrote: >=20 > As long as you keep the ASID value in EDX[15:0] as 0, then you won't > #GP. ASID 0 is the host/hypervisor. An ASID > 0 belongs to a guest. >=20 I've been spending some time reading the KVM code, and I don't think invlpgb would be currently useful with KVM. >From reading pre_svm_run(), new_asid(), and svm_vcpu_run(), it looks like the ASID number used might be different for each VCPU, assigned on a per (physical host) CPU basis. It would take some surgery to change that around. Some googling around also suggests that the ASID address space is even more limited than the PCID address space :( --=20 All Rights Reversed.