Re: [PATCH 1/2] cpufreq: dt: Don't (ab)use dev_pm_opp_get_opp_table() to create OPP table

From: Viresh Kumar <viresh.kumar@linaro.org>
To: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>,
	linux-pm@vger.kernel.org,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Stephen Boyd <sboyd@kernel.org>, Nishanth Menon <nm@ti.com>,
	digetx@gmail.com, Stephan Gerhold <stephan@gerhold.net>,
	linux-kernel@vger.kernel.org,
	Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Subject: Re: [PATCH 1/2] cpufreq: dt: Don't (ab)use dev_pm_opp_get_opp_table() to create OPP table
Date: Tue, 10 Nov 2020 11:30:11 +0530	[thread overview]
Message-ID: <20201110060011.7unghpidbzobqhq7@vireshk-i7> (raw)
In-Reply-To: <2924bddd-d237-aa57-abb1-a67723770e97@samsung.com>

On 09-11-20, 13:42, Marek Szyprowski wrote:
> This patch landed in linux next-20201109 as commit e8f7703f8fe5 
> ("cpufreq: dt: Don't (ab)use dev_pm_opp_get_opp_table() to create OPP 
> table"). Sadly it causes regression on some Samsung Exynos based boards:
> 
> 8<--- cut here ---
> Unable to handle kernel paging request at virtual address ffffff37
> pgd = (ptrval)
> [ffffff37] *pgd=4ffff841, *pte=00000000, *ppte=00000000
> Internal error: Oops: 27 [#1] PREEMPT SMP ARM
> Modules linked in:
> usb 3-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
> CPU: 3 PID: 1 Comm: swapper/0 Not tainted 5.10.0-rc1-00007-ge8f7703f8fe5 
> #1908
> Hardware name: Samsung Exynos (Flattened Device Tree)
> PC is at dev_pm_opp_put_regulators+0x8/0xf0
> LR is at dt_cpufreq_probe+0x19c/0x3fc

Does this fix it for you ?

diff --git a/drivers/cpufreq/cpufreq-dt.c b/drivers/cpufreq/cpufreq-dt.c
index 66b3db5efb53..5aa3d4e3140d 100644
--- a/drivers/cpufreq/cpufreq-dt.c
+++ b/drivers/cpufreq/cpufreq-dt.c
@@ -228,7 +228,7 @@ static int dt_cpufreq_early_init(struct device *dev, int cpu)
                        if (ret != -EPROBE_DEFER)
                                dev_err(cpu_dev, "failed to set regulators: %d\n",
                                        ret);
-                       goto out;
+                       goto free_cpumask;
                }
        }
 
@@ -293,6 +293,7 @@ static int dt_cpufreq_early_init(struct device *dev, int cpu)
                dev_pm_opp_of_cpumask_remove_table(priv->cpus);
        if (priv->opp_table)
                dev_pm_opp_put_regulators(priv->opp_table);
+free_cpumask:
        free_cpumask_var(priv->cpus);
        return ret;
 }


-- 
viresh
