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Y. Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , Long Li , Ajay Kaher , Alexey Makhalov , Jan Kiszka , Dave Hansen , Andy Lutomirski , Peter Zijlstra , Juergen Gross , Daniel Lezcano , Thomas Gleixner , John Stultz , Vitaly Kuznetsov , Broadcom internal kernel review list , Boris Ostrovsky , Stephen Boyd , Miroslav Lichvar , x86@kernel.org, linux-coco@lists.linux.dev, kvm@vger.kernel.org, linux-hyperv@vger.kernel.org, virtualization@lists.linux.dev, linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org, Michael Kelley , Tom Lendacky , Nikunj A Dadhania , Thomas Gleixner Subject: Re: [PATCH v6 00/51] x86: Try to wrangle PV clocks vs. TSC User-Agent: K-9 Mail for Android In-Reply-To: References: <20260806233609.212337-1-seanjc@google.com> Message-ID: <375997C1-577B-440C-B347-B8D256FA84B3@alien8.de> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On November 4, 2026 7:37:50 PM UTC, Sean Christopherson wrote: >On Thu, Sep 10, 2026, David Woodhouse wrote: >> On Thu, 2026-09-10 at 10:59 -0700, Sean Christopherson wrote: >> > On Thu, Aug 06, 2026, Sean Christopherson wrote: >> > > The primary goal of this series to fix flaws with SNP and TDX guest= s where a >> > > PV clock provided by the untrusted hypervisor is used instead of th= e secure >> > > TSC that is controlled by trusted firmware=2E >> > >=20 >> > > The secondary goal is modernize running under KVM=2E=C2=A0 Currentl= y, KVM guests will >> > > use TSC for clocksource, but not sched_clock=2E=C2=A0 And Linux-as-= a-KVM-guest doesn't >> > > support paravirt enumeration of the TSC/APIC frequencies, even thou= gh QEMU >> > > provides that information by default=2E >> > >=20 >> > > The tertiary goal is to clean up the PV clock code to deduplicate l= ogic across >> > > hypervisors, and to hopefully make it all easier to maintain going = forward=2E >> > >=20 >> > > The quaternary goal is to clean up the TSC calibration code, which = was made >> > > stupidly hard to follow by hypervisor code mixing in with the nativ= e >> > > calibration routines, instead of being implemented as a pure altern= ative=2E >> > >=20 >> > > Note, the VMware and Xen changes still probably should get acks fro= m those >> > > maintainers, as my understanding of what they're trying to do may b= e flawed=2E >> >=20 >> > This (thankfully) still applies cleanly=2E=C2=A0 What can I do to hel= p move this forward? >>=20 >> Nudge Thomas to spot that this is guest-side and we want him to pick it= up, I guess? > >Amazingly, still applies cleanly on 7=2E4-rc1 and tip/master=2E I know w= e're shortly >after the merge window, but this has been sitting idle for months and add= resses >issues that are impacting a variety of end users=2E > >Note, this also provides meaningful hardening for SNP and TDX=2E /me sta= res intently >in the direction of Dave and Boris=2E Would you believe me if I told you you're in the "review" mbox? The damn thing just keeps growing constantly :-/ I would love it if we had a review scoring thing like the net folks - whoe= ver reviews others' patches, gets looked at first=2E=2E=2E and no, I don't = mean you with that=2E :) --=20 Small device=2E Typos and formatting crap