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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 11:36 -0600, Tom Lendacky wrote: >=20 > Right, but the ASID valid bit is not set, so the flushing may match > more > than just host/hypervisor TLB entries. >=20 Good point, when using SVM these flushes could result in flushing more TLB entries than we really want. On the flip side, when SVM is not initialized, the invlpgb instruction will fail with a general protection fault if we have anything at all in the ASID field. I don't know whether setting the ASID valid bit in rAX will cause a system to crash when SVM is not enabled or initialized. --=20 All Rights Reversed.