All of lore.kernel.org
 help / color / mirror / Atom feed
From: Greg KH <gregkh@linuxfoundation.org>
To: Will Deacon <will@kernel.org>
Cc: Mark Brown <broonie@kernel.org>, Sasha Levin <sashal@kernel.org>,
	linux-kernel@vger.kernel.org, stable@vger.kernel.org,
	Kristina Martsenko <kristina.martsenko@arm.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	james.morse@arm.com, mark.rutland@arm.com, amit.kachhap@arm.com,
	maz@kernel.org, anshuman.khandual@arm.com, joey.gouly@arm.com,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH AUTOSEL 6.4 07/12] arm64: cpufeature: detect FEAT_HCX
Date: Mon, 10 Jul 2023 15:31:42 +0200	[thread overview]
Message-ID: <2023071024-unpaved-washed-4d7d@gregkh> (raw)
In-Reply-To: <20230710094438.GD32673@willie-the-truck>

On Mon, Jul 10, 2023 at 10:44:38AM +0100, Will Deacon wrote:
> On Sun, Jul 09, 2023 at 10:13:29PM +0100, Mark Brown wrote:
> > On Sun, Jul 09, 2023 at 10:56:13AM -0400, Sasha Levin wrote:
> > > On Mon, Jul 03, 2023 at 12:51:57PM +0100, Mark Brown wrote:
> > > > On Sun, Jul 02, 2023 at 03:50:52PM -0400, Sasha Levin wrote:
> > 
> > > > > KVM currently relies on the register being present on all CPUs (or
> > > > > none), so the kernel will panic if that is not the case. Fortunately no
> > > > > such systems currently exist, but this can be revisited if they appear.
> > > > > Note that the kernel will not panic if CONFIG_KVM is disabled.
> > 
> > > > This is a new feature, it's not clear why we'd backport it (especially
> > > > since it's a new feature which is a dependency for other features rather
> > > > than something that people can use outside of the kernel)?
> > 
> > > The second paragraph (above) suggested it should be.
> > 
> > That's saying that the code won't work properly on systems where some
> > but not all of the CPUs support the feature.  Note that the changelog
> > says nothing about fixing any issue here.
> 
> Try reading it like a GPU running an ML model:
> 
>   "This is not a new feature, it's especially clear why we'd backport it."
> 
> Makes sense. *sigh*
> 
> We've been considering opting arm64 out of this for a while, but I don't
> think we do a great job of CC'ing stable either (I certainly forget to
> add it all the time and then hope that the Fixes: tag does the job),so
> it's not obviously going to improve things.
> 
> Maybe we just need a commit hook that yells if something with a Fixes:
> tag doesn't have a CC: stable on it?

I could start doing that, it's going to be really noisy...

greg k-h

WARNING: multiple messages have this Message-ID (diff)
From: Greg KH <gregkh@linuxfoundation.org>
To: Will Deacon <will@kernel.org>
Cc: Mark Brown <broonie@kernel.org>, Sasha Levin <sashal@kernel.org>,
	linux-kernel@vger.kernel.org, stable@vger.kernel.org,
	Kristina Martsenko <kristina.martsenko@arm.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	james.morse@arm.com, mark.rutland@arm.com, amit.kachhap@arm.com,
	maz@kernel.org, anshuman.khandual@arm.com, joey.gouly@arm.com,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH AUTOSEL 6.4 07/12] arm64: cpufeature: detect FEAT_HCX
Date: Mon, 10 Jul 2023 15:31:42 +0200	[thread overview]
Message-ID: <2023071024-unpaved-washed-4d7d@gregkh> (raw)
In-Reply-To: <20230710094438.GD32673@willie-the-truck>

On Mon, Jul 10, 2023 at 10:44:38AM +0100, Will Deacon wrote:
> On Sun, Jul 09, 2023 at 10:13:29PM +0100, Mark Brown wrote:
> > On Sun, Jul 09, 2023 at 10:56:13AM -0400, Sasha Levin wrote:
> > > On Mon, Jul 03, 2023 at 12:51:57PM +0100, Mark Brown wrote:
> > > > On Sun, Jul 02, 2023 at 03:50:52PM -0400, Sasha Levin wrote:
> > 
> > > > > KVM currently relies on the register being present on all CPUs (or
> > > > > none), so the kernel will panic if that is not the case. Fortunately no
> > > > > such systems currently exist, but this can be revisited if they appear.
> > > > > Note that the kernel will not panic if CONFIG_KVM is disabled.
> > 
> > > > This is a new feature, it's not clear why we'd backport it (especially
> > > > since it's a new feature which is a dependency for other features rather
> > > > than something that people can use outside of the kernel)?
> > 
> > > The second paragraph (above) suggested it should be.
> > 
> > That's saying that the code won't work properly on systems where some
> > but not all of the CPUs support the feature.  Note that the changelog
> > says nothing about fixing any issue here.
> 
> Try reading it like a GPU running an ML model:
> 
>   "This is not a new feature, it's especially clear why we'd backport it."
> 
> Makes sense. *sigh*
> 
> We've been considering opting arm64 out of this for a while, but I don't
> think we do a great job of CC'ing stable either (I certainly forget to
> add it all the time and then hope that the Fixes: tag does the job),so
> it's not obviously going to improve things.
> 
> Maybe we just need a commit hook that yells if something with a Fixes:
> tag doesn't have a CC: stable on it?

I could start doing that, it's going to be really noisy...

greg k-h

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  reply	other threads:[~2023-07-10 13:32 UTC|newest]

Thread overview: 36+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-07-02 19:50 [PATCH AUTOSEL 6.4 01/12] platform/chrome: cros_ec: Report EC panic as uevent Sasha Levin
2023-07-02 19:50 ` [PATCH AUTOSEL 6.4 02/12] ACPI: x86: Add skip i2c clients quirk for Nextbook Ares 8A Sasha Levin
2023-07-02 19:50 ` [PATCH AUTOSEL 6.4 03/12] ACPI: button: Add lid disable DMI " Sasha Levin
2023-07-02 19:50 ` [PATCH AUTOSEL 6.4 04/12] ACPI: x86: Add ACPI_QUIRK_UART1_SKIP for Lenovo Yoga Book yb1-x90f/l Sasha Levin
2023-07-02 19:50 ` [PATCH AUTOSEL 6.4 05/12] ACPI: video: Add backlight=native DMI quirk for Apple iMac11,3 Sasha Levin
2023-07-02 19:50 ` [PATCH AUTOSEL 6.4 06/12] ACPI: video: Add backlight=native DMI quirk for Lenovo ThinkPad X131e (3371 AMD version) Sasha Levin
2023-07-02 19:50 ` [PATCH AUTOSEL 6.4 07/12] arm64: cpufeature: detect FEAT_HCX Sasha Levin
2023-07-02 19:50   ` Sasha Levin
2023-07-03 11:51   ` Mark Brown
2023-07-03 11:51     ` Mark Brown
2023-07-09 14:56     ` Sasha Levin
2023-07-09 14:56       ` Sasha Levin
2023-07-09 21:13       ` Mark Brown
2023-07-09 21:13         ` Mark Brown
2023-07-10  9:44         ` Will Deacon
2023-07-10  9:44           ` Will Deacon
2023-07-10 13:31           ` Greg KH [this message]
2023-07-10 13:31             ` Greg KH
2023-07-10 13:47             ` Mark Brown
2023-07-10 13:47               ` Mark Brown
2023-07-10 14:09               ` Greg KH
2023-07-10 14:09                 ` Greg KH
2023-07-02 19:50 ` [PATCH AUTOSEL 6.4 08/12] ACPI: resource: Remove "Zen" specific match and quirks Sasha Levin
2023-07-02 19:50 ` [PATCH AUTOSEL 6.4 09/12] arm64: set __exception_irq_entry with __irq_entry as a default Sasha Levin
2023-07-02 19:50   ` Sasha Levin
2023-07-02 19:50 ` [PATCH AUTOSEL 6.4 10/12] arm64: mm: fix VA-range sanity check Sasha Levin
2023-07-02 19:50   ` Sasha Levin
2023-07-02 19:50 ` [PATCH AUTOSEL 6.4 11/12] drivers/perf: hisi: Add support for HiSilicon H60PA and PAv3 PMU driver Sasha Levin
2023-07-02 19:50   ` Sasha Levin
2023-07-03 10:14   ` Mark Rutland
2023-07-03 10:14     ` Mark Rutland
2023-07-21 15:13     ` Sasha Levin
2023-07-21 15:13       ` Sasha Levin
2023-07-02 19:50 ` [PATCH AUTOSEL 6.4 12/12] ACPI: video: Add backlight=native DMI quirk for Dell Studio 1569 Sasha Levin
2023-07-10 22:46 ` [PATCH AUTOSEL 6.4 01/12] platform/chrome: cros_ec: Report EC panic as uevent Brian Norris
2023-07-21 15:11   ` Sasha Levin

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=2023071024-unpaved-washed-4d7d@gregkh \
    --to=gregkh@linuxfoundation.org \
    --cc=amit.kachhap@arm.com \
    --cc=anshuman.khandual@arm.com \
    --cc=broonie@kernel.org \
    --cc=catalin.marinas@arm.com \
    --cc=james.morse@arm.com \
    --cc=joey.gouly@arm.com \
    --cc=kristina.martsenko@arm.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mark.rutland@arm.com \
    --cc=maz@kernel.org \
    --cc=sashal@kernel.org \
    --cc=stable@vger.kernel.org \
    --cc=will@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.