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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.54.1 (3.54.1-1.fc41) MIME-Version: 1.0 X-Rspam-User: X-Rspamd-Queue-Id: C17D214000A X-Rspamd-Server: rspam07 X-Stat-Signature: kpeaiqqxg6w8e36zcey8ffdcdj8owjs4 X-HE-Tag: 1739206300-25493 X-HE-Meta: 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 LjBZNiCr 9mBucJU5sFI92IAUwRd9xRHGdGgSpsKhgP8u0By/zo6oThmbv+/6p7xZQJafFdDOdFaS607s/GkY4z7vs1GHqJfmAgyp6LE+t6MgxPOK1DyCR2GJB+gaXBfG2BQo5rdF25Bj7Uhz8VedHNL/jDsk6KXaxXffbeh03VXUnq2Csqgd7j+oND4Z0Hy4Cn23HDY/l5cRPabLlZi5aKdhB41dAMauNXdyz57H709OppM2SPuMx1KyKfQAAV+5RVmf213sgRjnMtCCsgfdbwqQ0ICMi5DoDkdoSFuVaXH2VOu5gg0TBMqjE4HrtHgpNiazo5P9NeLfYMvDptHU2qQevXKouEPvVA+O0pOjLPJBQGYSN5cqH8ZojBwecPg5M2RFKa5oYlNjLIra+qghpO7NbH9qmCJV7BsPaMgAND/rRJWYYQUOI74I= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, 2025-02-10 at 15:30 +0800, Vern Hao wrote: > I do some test=C2=A0on my=C2=A0=C2=A0Machine with=C2=A0AMD EPYC 7K83,=C2= =A0 these patches=C2=A0work > on my host,=C2=A0 but failed on my guest=C2=A0with qemu. >=20 > in host, use lscpu cmd, you can see=C2=A0=C2=A0invlpgb=C2=A0in flags,=C2= =A0 but in guest > no. >=20 > So are you plan=C2=A0to support it in guest? How exactly did it fail in the guest? Did the guest simply not use INVLPGB because that CPUID flag was not presented in the CPUID that qemu shows to the guest, or did things crash somehow? My understanding is that while INVLPGB can work in guests, actually implementing that is a whole other can of worms, and definitely not something we should try to tackle at the same time as bare metal support. A TLB flush hypercall, with IRQ-less flushing on the hypervisor side will probably get us 90% of the way there, potentially with less overall complexity than actually supporting INVLPGB in the guest. --=20 All Rights Reversed.