From: Dietmar Eggemann <dietmar.eggemann@arm.com>
To: Zeng Tao <prime.zeng@hisilicon.com>, sudeep.holla@arm.com
Cc: linuxarm@huawei.com,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
"Rafael J. Wysocki" <rafael@kernel.org>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] cpu-topology: Skip the exist but not possible cpu nodes
Date: Mon, 6 Jan 2020 19:42:06 +0100 [thread overview]
Message-ID: <14a39167-5704-f406-614d-4d25b8fe8c68@arm.com> (raw)
In-Reply-To: <1577935489-25245-1-git-send-email-prime.zeng@hisilicon.com>
On 02/01/2020 04:24, Zeng Tao wrote:
> When CONFIG_NR_CPUS is smaller than the cpu nodes defined in the device
> tree, the cpu node parsing will fail. And this is not reasonable for a
> legal device tree configs.
> In this patch, skip such cpu nodes rather than return an error.
Is this extra code really necessary?
Currently you get warnings indicating that CONFIG_NR_CPUS is too small
so you could correct the setup issue easily.
Example: Arm64 Juno board
$ grep "cpu@" ./arch/arm64/boot/dts/arm/juno.dts
A57_0: cpu@0 {
A57_1: cpu@1 {
A53_0: cpu@100 {
A53_1: cpu@101 {
A53_2: cpu@102 {
A53_3: cpu@103 {
root@juno:~# uname -r
5.5.0-rc5
root@juno:~# zcat /proc/config.gz | grep CONFIG_NR_CPUS
CONFIG_NR_CPUS=4
root@juno:~# cat /proc/cpuinfo | grep ^proc
processor : 0
processor : 1
processor : 2
processor : 3
root@juno:~# dmesg | grep "Unable\|Can't"
[ 0.085089] Unable to find CPU node for /cpus/cpu@102
[ 0.090179] /cpus/cpu-map/cluster1/core2: Can't get CPU for leaf core
[...]
next prev parent reply other threads:[~2020-01-06 18:42 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-02 3:24 [PATCH] cpu-topology: Skip the exist but not possible cpu nodes Zeng Tao
2020-01-06 18:42 ` Dietmar Eggemann [this message]
2020-01-07 1:35 ` Zengtao (B)
2020-01-07 13:12 ` Dietmar Eggemann
2020-01-08 2:01 ` Zengtao (B)
2020-01-07 14:49 ` Sudeep Holla
2020-01-08 1:57 ` Zengtao (B)
2020-01-10 11:16 ` Sudeep Holla
2020-01-11 2:03 ` Zengtao (B)
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=14a39167-5704-f406-614d-4d25b8fe8c68@arm.com \
--to=dietmar.eggemann@arm.com \
--cc=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linuxarm@huawei.com \
--cc=prime.zeng@hisilicon.com \
--cc=rafael@kernel.org \
--cc=sudeep.holla@arm.com \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).