From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nishanth Menon Subject: Re: [PATCH] CLK: TI: consider the fact that of_clk_get() might return an error Date: Wed, 17 Sep 2014 07:52:33 -0500 Message-ID: <54198411.1080706@ti.com> References: <1410451272-31068-1-git-send-email-bigeasy@linutronix.de> Reply-To: nm@ti.com Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-oi0-f43.google.com ([209.85.218.43]:44307 "EHLO mail-oi0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755199AbaIQMwf (ORCPT ); Wed, 17 Sep 2014 08:52:35 -0400 Received: by mail-oi0-f43.google.com with SMTP id v63so784856oia.30 for ; Wed, 17 Sep 2014 05:52:34 -0700 (PDT) In-Reply-To: <1410451272-31068-1-git-send-email-bigeasy@linutronix.de> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Sebastian Andrzej Siewior , Tero Kristo Cc: Mike Turquette , linux-omap@vger.kernel.org On 09/11/2014 11:01 AM, Sebastian Andrzej Siewior wrote: > I "forgot" to update the dtb and the kernel crashed: > |Unable to handle kernel NULL pointer dereference at virtual address 0000002e > |PC is at __clk_get_flags+0x4/0xc > |LR is at ti_dt_clockdomains_setup+0x70/0xe8 > > because I did not have the clock nodes. of_clk_get() returns an error > pointer which is not checked here. > > Signed-off-by: Sebastian Andrzej Siewior > --- > drivers/clk/ti/clockdomain.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/clk/ti/clockdomain.c b/drivers/clk/ti/clockdomain.c > index f1e0038d76ac..fdd458600c2c 100644 > --- a/drivers/clk/ti/clockdomain.c > +++ b/drivers/clk/ti/clockdomain.c > @@ -36,6 +36,11 @@ static void __init of_ti_clockdomain_setup(struct device_node *node) > > for (i = 0; i < num_clks; i++) { > clk = of_clk_get(node, i); > + if (IS_ERR(clk)) { > + pr_err("Failed get %s' clock nr %d (%ld)\n", > + node->full_name, i, PTR_ERR(clk)); Could you add %s: __func__ as well - it kinda helps understand this is part of clockdomain setup and not some driver cribbing that it did not get some clock. > + continue; > + } > if (__clk_get_flags(clk) & CLK_IS_BASIC) { > pr_warn("can't setup clkdm for basic clk %s\n", > __clk_get_name(clk)); >