LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Stephen Boyd <sboyd@codeaurora.org>
To: Alban Browaeys <alban.browaeys@gmail.com>,
	Tomeu Vizoso <tomeu.vizoso@collabora.com>,
	Mike Turquette <mturquette@linaro.org>
Cc: linux-kernel@vger.kernel.org, Alban Browaeys <prahal@yahoo.com>
Subject: Re: [PATCH 2/2] clk: Fix OOPS calling hlist_del on an already poisoned hlist.
Date: Thu, 05 Feb 2015 11:33:27 -0800	[thread overview]
Message-ID: <54D3C587.9020309@codeaurora.org> (raw)
In-Reply-To: <1423160690-7853-2-git-send-email-prahal@yahoo.com>

On 02/05/15 10:24, Alban Browaeys wrote:
> Put is called more than once, thus hlist_del ends up on a poisoned
> list.

Why is clk_put() called more than once on the same clk pointer? Where
does this happe

>
> Move hlist_del to the __clk_release handler managed by kref instead
> of calling it in _clk_put.
>
> Fixes: 1c8e600440c7 ("clk: Add rate constraints to clocks")
> Signed-off-by: Alban Browaeys <prahal@yahoo.com>
> ---
>  drivers/clk/clk.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
> index 8f33722..f1d4b33 100644
> --- a/drivers/clk/clk.c
> +++ b/drivers/clk/clk.c
> @@ -2489,6 +2489,9 @@ static void __clk_release(struct kref *ref)
>  	struct clk *clk = container_of(&core, struct clk, core);
>  	int i = core->num_parents;
>  
> +	hlist_del(&clk->child_node);
> +	clk_core_set_rate_nolock(clk->core, clk->core->req_rate);
> +
>  	kfree(core->parents);
>  	while (--i >= 0)
>  		kfree_const(core->parent_names[i]);
> @@ -2666,8 +2669,6 @@ void __clk_put(struct clk *clk)
>  
>  	clk_prepare_lock();
>  
> -	hlist_del(&clk->child_node);

Ugh we should call this clks_node or something so that we don't confuse
it with child_node in clk_core.

> -	clk_core_set_rate_nolock(clk->core, clk->core->req_rate);
>  	owner = clk->core->owner;
>  	kref_put(&clk->core->ref, __clk_release);
>  


-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project


  reply	other threads:[~2015-02-05 19:33 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-02-05 18:24 [PATCH 1/2] clk: Fix __clk_get access to already freed owner field Alban Browaeys
2015-02-05 18:24 ` [PATCH 2/2] clk: Fix OOPS calling hlist_del on an already poisoned hlist Alban Browaeys
2015-02-05 19:33   ` Stephen Boyd [this message]
2015-02-05 20:56     ` Alban Browaeys
2015-02-05 19:30 ` [PATCH 1/2] clk: Fix __clk_get access to already freed owner field Stephen Boyd
2015-02-05 20:43   ` Alban Browaeys
2015-02-05 21:03     ` Stephen Boyd
2015-02-05 21:30       ` Alban Browaeys
2015-02-05 21:45         ` Stephen Boyd
2015-02-06  9:52           ` Alban Browaeys

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=54D3C587.9020309@codeaurora.org \
    --to=sboyd@codeaurora.org \
    --cc=alban.browaeys@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mturquette@linaro.org \
    --cc=prahal@yahoo.com \
    --cc=tomeu.vizoso@collabora.com \
    --subject='Re: [PATCH 2/2] clk: Fix OOPS calling hlist_del on an already poisoned hlist.' \
    /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

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).