From: Jakub Kicinski <kuba@kernel•org>
To: David Woodhouse <dwmw2@infradead•org>
Cc: Richard Cochran <richardcochran@gmail•com>,
Peter Hilber <peter.hilber@opensynergy•com>,
linux-kernel@vger•kernel.org, virtualization@lists•linux.dev,
linux-arm-kernel@lists•infradead.org, linux-rtc@vger•kernel.org,
"Ridoux, Julien" <ridouxj@amazon•com>,
virtio-dev@lists•linux.dev, "Luu, Ryan" <rluu@amazon•com>,
"Chashper, David" <chashper@amazon•com>,
"Mohamed Abuelfotoh, Hazem" <abuehaze@amazon•com>,
Paolo Abeni <pabeni@redhat•com>,
"Christopher S . Hall" <christopher.s.hall@intel•com>,
Jason Wang <jasowang@redhat•com>,
John Stultz <jstultz@google•com>,
"Michael S . Tsirkin" <mst@redhat•com>,
netdev@vger•kernel.org, Stephen Boyd <sboyd@kernel•org>,
Thomas Gleixner <tglx@linutronix•de>,
Xuan Zhuo <xuanzhuo@linux•alibaba.com>,
Marc Zyngier <maz@kernel•org>,
Mark Rutland <mark.rutland@arm•com>,
Daniel Lezcano <daniel.lezcano@linaro•org>,
Alessandro Zummo <a.zummo@towertech•it>,
Alexandre Belloni <alexandre.belloni@bootlin•com>,
qemu-devel <qemu-devel@nongnu•org>,
Simon Horman <horms@kernel•org>
Subject: Re: [PATCH net-next v7] ptp: Add support for the AMZNC10C 'vmclock' device
Date: Mon, 28 Oct 2024 09:12:56 -0700 [thread overview]
Message-ID: <20241028091256.1b0752b4@kernel.org> (raw)
In-Reply-To: <c1eb33ffd66d45af77dea58db8bdca3dcd2468c4.camel@infradead.org>
On Sat, 19 Oct 2024 18:49:24 +0100 David Woodhouse wrote:
> > Yes please and thank you! We gotta straighten it out before
> > the merge window.
>
> Hm, as I (finally) come to do that, I realise that many of the others
> defined in drivers/ptp/Kconfig are also 'default y'. Which is only
> really 'default PTP_1588_CLOCK' in practice since they all depend on
> that.
AFAICT nothing defaulted to enabled since 2017, so I'd chalk it up
to us getting better at catching mistakes over time.
> Most importantly, PTP_1588_CLOCK_KVM is 'default y'. And that one is
> fundamentally broken (at least in the presence of live migration if
> guests care about their clock suddenly being wrong) which is why it's
> being superseded by the new VMCLOCK thing. We absolutely don't want to
> leave the _KVM one enabled by default and not its _VMCLOCK replacement.
You can default to .._CLOCK_KVM, and provide the explanation in
the commit message and Kconfig help.
Or if you feel strongly even make CLOCK_KVM depend on the new one?
> Please advise... I suspect the best answer is to leave it as it is?
I'd really rather not. Linus has complained to us about Kconfig symbols
appearing / getting enabled by default multiple times in the past.
Sorry for the delay, vacation time.
next prev parent reply other threads:[~2024-10-28 16:12 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-10-06 7:17 [PATCH net-next v7] ptp: Add support for the AMZNC10C 'vmclock' device David Woodhouse
2024-10-07 16:09 ` Richard Cochran
2024-10-09 11:20 ` patchwork-bot+netdevbpf
2024-10-10 0:32 ` Jakub Kicinski
2024-10-14 7:25 ` David Woodhouse
2024-10-14 20:12 ` Jakub Kicinski
2024-10-19 17:49 ` David Woodhouse
2024-10-28 16:12 ` Jakub Kicinski [this message]
2024-10-28 16:17 ` David Woodhouse
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20241028091256.1b0752b4@kernel.org \
--to=kuba@kernel$(echo .)org \
--cc=a.zummo@towertech$(echo .)it \
--cc=abuehaze@amazon$(echo .)com \
--cc=alexandre.belloni@bootlin$(echo .)com \
--cc=chashper@amazon$(echo .)com \
--cc=christopher.s.hall@intel$(echo .)com \
--cc=daniel.lezcano@linaro$(echo .)org \
--cc=dwmw2@infradead$(echo .)org \
--cc=horms@kernel$(echo .)org \
--cc=jasowang@redhat$(echo .)com \
--cc=jstultz@google$(echo .)com \
--cc=linux-arm-kernel@lists$(echo .)infradead.org \
--cc=linux-kernel@vger$(echo .)kernel.org \
--cc=linux-rtc@vger$(echo .)kernel.org \
--cc=mark.rutland@arm$(echo .)com \
--cc=maz@kernel$(echo .)org \
--cc=mst@redhat$(echo .)com \
--cc=netdev@vger$(echo .)kernel.org \
--cc=pabeni@redhat$(echo .)com \
--cc=peter.hilber@opensynergy$(echo .)com \
--cc=qemu-devel@nongnu$(echo .)org \
--cc=richardcochran@gmail$(echo .)com \
--cc=ridouxj@amazon$(echo .)com \
--cc=rluu@amazon$(echo .)com \
--cc=sboyd@kernel$(echo .)org \
--cc=tglx@linutronix$(echo .)de \
--cc=virtio-dev@lists$(echo .)linux.dev \
--cc=virtualization@lists$(echo .)linux.dev \
--cc=xuanzhuo@linux$(echo .)alibaba.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox