From: Kevin Hilman <khilman@baylibre•com>
To: Will Deacon <will@kernel•org>, linux-arm-kernel@lists•infradead.org
Cc: Mark Rutland <mark.rutland@arm•com>,
Suzuki Poulose <suzuki.poulose@arm•com>,
Marc Zyngier <maz@kernel•org>,
Catalin Marinas <catalin.marinas@arm•com>,
linux-amlogic@lists•infradead.org, Will Deacon <will@kernel•org>
Subject: Re: [PATCH] arm64: cpufeature: Don't treat granule sizes as strict
Date: Mon, 12 Aug 2019 13:57:45 -0700 [thread overview]
Message-ID: <7himr214qe.fsf@baylibre.com> (raw)
In-Reply-To: <20190812150225.25386-1-will@kernel.org>
Will Deacon <will@kernel•org> writes:
> If a CPU doesn't support the page size for which the kernel is
> configured, then we will complain and refuse to bring it online. For
> secondary CPUs (and the boot CPU on a system booting with EFI), we will
> also print an error identifying the mismatch.
>
> Consequently, the only time that the cpufeature code can detect a
> granule size mismatch is for a granule other than the one that is
> currently being used. Although we would rather such systems didn't
> exist, we've unfortunately lost that battle and Kevin reports that
> on his amlogic S922X (odroid-n2 board) we end up warning and taining
> with defconfig because 16k pages are not supported by all of the CPUs.
>
> In such a situation, we don't actually care about the feature mismatch,
> particularly now that KVM only exposes the sanitised view of the CPU
> registers. Treat the granule fields as non-strict and let Kevin run
> without a tainted kernel.
>
> Cc: Mark Rutland <mark.rutland@arm•com>
> Cc: Marc Zyngier <maz@kernel•org>
> Cc: Suzuki Poulose <suzuki.poulose@arm•com>
> Cc: Catalin Marinas <catalin.marinas@arm•com>
> Reported-by: Kevin Hilman <khilman@baylibre•com>
> Signed-off-by: Will Deacon <will@kernel•org>
Tested-by: Kevin Hilman <khilman@baylibre•com>
Thanks for the fix Will!
Kevin
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists•infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2019-08-12 20:57 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-12 15:02 [PATCH] arm64: cpufeature: Don't treat granule sizes as strict Will Deacon
2019-08-12 15:04 ` Mark Rutland
2019-08-12 15:48 ` Suzuki K Poulose
2019-08-12 20:57 ` Kevin Hilman [this message]
2019-08-13 11:59 ` Catalin Marinas
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=7himr214qe.fsf@baylibre.com \
--to=khilman@baylibre$(echo .)com \
--cc=catalin.marinas@arm$(echo .)com \
--cc=linux-amlogic@lists$(echo .)infradead.org \
--cc=linux-arm-kernel@lists$(echo .)infradead.org \
--cc=mark.rutland@arm$(echo .)com \
--cc=maz@kernel$(echo .)org \
--cc=suzuki.poulose@arm$(echo .)com \
--cc=will@kernel$(echo .)org \
/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