From: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
To: Stephen Boyd <sboyd@codeaurora.org>,
Russell King <linux@armlinux.org.uk>
Cc: Linux-Kernel <linux-kernel@vger.kernel.org>,
Linux-ALSA <alsa-devel@alsa-project.org>,
<linux-clk@vger.kernel.org>,
Linux-Renesas <linux-renesas-soc@vger.kernel.org>
Subject: Question about of_clk_put ?
Date: Wed, 29 Mar 2017 01:16:15 +0000 [thread overview]
Message-ID: <87wpb8ansx.wl%kuninori.morimoto.gx@renesas.com> (raw)
In-Reply-To: <874m2jvtmw.wl%kuninori.morimoto.gx@renesas.com>
Hi Stephen
Now, I'm using devm_get_clk_from_child() (= linux/drivers/clk/clk-devres.c)
and I got Oops if I do bind/unbind driver several times.
[ 32.008847] Unable to handle kernel paging request at virtual address d503201faa1e03e0
[ 32.017124] pgd = ffff8006f9060000
[ 32.020883] [d503201faa1e03e0] *pgd=0000000000000000
[ 32.026243] Internal error: Oops: 96000004 [#1] PREEMPT SMP
[ 32.032198] CPU: 0 PID: 934 Comm: kworker/0:2 Not tainted 4.11.0-rc3+ #1259
[ 32.039573] Hardware name: Renesas Salvator-X board based on r8a7795 (DT)
[ 32.046814] Workqueue: events deferred_probe_work_func
[ 32.052405] task: ffff8006fad2d800 task.stack: ffff8006f90b8000
[ 32.058809] PC is at __of_clk_get_from_provider+0x174/0x1b0
[ 32.064878] LR is at __of_clk_get_from_provider+0x164/0x1b0
....
[ 32.746677] [<ffff0000083b581c>] __of_clk_get_from_provider+0x174/0x1b0
[ 32.754131] [<ffff0000083aded4>] __of_clk_get_by_name+0x104/0x140
[ 32.761058] [<ffff0000083adfd8>] of_clk_get_by_name+0x30/0x50
[ 32.767630] [<ffff0000083add1c>] devm_get_clk_from_child+0x54/0xb0
...
I tried to find the criminal point, but, I couldn't specify where it is.
Sometimes it is NULL pointer access crashed,
sometimes it is crashed on of_clk_src_onecell_get(),
sometimes there is no Oops.
I want to solve this issue, but I want to know about of_clk_put as 1st step.
In devm_clk_get() case, it is using clk_get() <-> clk_put() pair, this is OK.
In devm_get_clk_from_child() case, it is using of_clk_get_by_name() (= __of_clk_get())
<-> clk_put() pair.
If my understand was correct, __of_clk_get() uses __clk_create_clk(),
so, its pair should be __clk_free_clk() ?
I wonder I can find of_clk_get(), but couldn't find of_clk_put().
Is using of_clk_get() <-> clk_put() OK ?
Best regards
---
Kuninori Morimoto
next prev parent reply other threads:[~2017-03-29 1:16 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-12-05 5:22 [PATCH 0/3] clkdev: add devm_get_clk_from_child() Kuninori Morimoto
2016-12-05 5:23 ` [PATCH 1/3] " Kuninori Morimoto
2016-12-09 20:31 ` Russell King - ARM Linux
2016-12-05 5:23 ` [PATCH 2/3] ASoC: simple-card: use devm_get_clk_from_child() Kuninori Morimoto
2016-12-08 22:09 ` Stephen Boyd
2016-12-09 0:20 ` Kuninori Morimoto
2016-12-09 0:28 ` Stephen Boyd
2016-12-09 0:33 ` Kuninori Morimoto
2017-01-24 18:39 ` Applied "ASoC: simple-card: use devm_get_clk_from_child()" to the asoc tree Mark Brown
2016-12-05 5:23 ` [PATCH 3/3] ASoC: simple-card-utils: enable clocks/clock-names/clock-ranges Kuninori Morimoto
2016-12-08 22:09 ` Stephen Boyd
2016-12-09 0:21 ` Kuninori Morimoto
2016-12-09 0:22 ` Kuninori Morimoto
2016-12-09 0:26 ` Stephen Boyd
2016-12-09 0:55 ` Kuninori Morimoto
2016-12-08 22:08 ` [PATCH 0/3] clkdev: add devm_get_clk_from_child() Stephen Boyd
2016-12-09 0:25 ` Kuninori Morimoto
2016-12-15 12:21 ` Mark Brown
2016-12-16 0:02 ` Kuninori Morimoto
2017-03-29 1:16 ` Kuninori Morimoto [this message]
2017-03-30 1:46 ` [alsa-devel] Question about of_clk_put ? Kuninori Morimoto
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=87wpb8ansx.wl%kuninori.morimoto.gx@renesas.com \
--to=kuninori.morimoto.gx@renesas.com \
--cc=alsa-devel@alsa-project.org \
--cc=linux-clk@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-renesas-soc@vger.kernel.org \
--cc=linux@armlinux.org.uk \
--cc=sboyd@codeaurora.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 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).