[v2] cpufreq: mediatek: Fix potential deadlock problem in mtk_cpufreq_set_target

[PATCH v2] cpufreq: mediatek: Fix potential deadlock problem in mtk_cpufreq_set_target

Posted by Wan Jiabing 3 years, 9 months ago

Fix following coccichek error:
./drivers/cpufreq/mediatek-cpufreq.c:199:2-8: preceding lock on line
./drivers/cpufreq/mediatek-cpufreq.c:208:2-8: preceding lock on line

mutex_lock is acquired but not released before return.
Use 'goto out' to help releasing the mutex_lock.

Fixes: c210063b40ac ("cpufreq: mediatek: Add opp notification support")
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
---
Changelog:
v2:
- Fix a typo in 'Fixes' tag.
---
 drivers/cpufreq/mediatek-cpufreq.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c
index 75bf21ddf61f..4c6d53c99d79 100644
--- a/drivers/cpufreq/mediatek-cpufreq.c
+++ b/drivers/cpufreq/mediatek-cpufreq.c
@@ -196,7 +196,8 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
 
 	if (pre_vproc < 0) {
 		dev_err(cpu_dev, "invalid Vproc value: %d\n", pre_vproc);
-		return pre_vproc;
+		ret = pre_vproc;
+		goto out;
 	}
 
 	freq_hz = freq_table[index].frequency * 1000;
@@ -205,7 +206,8 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
 	if (IS_ERR(opp)) {
 		dev_err(cpu_dev, "cpu%d: failed to find OPP for %ld\n",
 			policy->cpu, freq_hz);
-		return PTR_ERR(opp);
+		ret = PTR_ERR(opp);
+		goto out;
 	}
 	vproc = dev_pm_opp_get_voltage(opp);
 	dev_pm_opp_put(opp);
-- 
2.35.1

Re: [PATCH v2] cpufreq: mediatek: Fix potential deadlock problem in mtk_cpufreq_set_target

Posted by Viresh Kumar 3 years, 9 months ago

On 10-05-22, 17:05, Wan Jiabing wrote:
> Fix following coccichek error:
> ./drivers/cpufreq/mediatek-cpufreq.c:199:2-8: preceding lock on line
> ./drivers/cpufreq/mediatek-cpufreq.c:208:2-8: preceding lock on line
> 
> mutex_lock is acquired but not released before return.
> Use 'goto out' to help releasing the mutex_lock.
> 
> Fixes: c210063b40ac ("cpufreq: mediatek: Add opp notification support")
> Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>

You should have added the review tag you received.

Applied. Thanks.

-- 
viresh

Re: [PATCH v2] cpufreq: mediatek: Fix potential deadlock problem in mtk_cpufreq_set_target

Posted by Jiabing Wan 3 years, 9 months ago


On 2022/5/10 17:12, Viresh Kumar wrote:
> On 10-05-22, 17:05, Wan Jiabing wrote:
>> Fix following coccichek error:
>> ./drivers/cpufreq/mediatek-cpufreq.c:199:2-8: preceding lock on line
>> ./drivers/cpufreq/mediatek-cpufreq.c:208:2-8: preceding lock on line
>>
>> mutex_lock is acquired but not released before return.
>> Use 'goto out' to help releasing the mutex_lock.
>>
>> Fixes: c210063b40ac ("cpufreq: mediatek: Add opp notification support")
>> Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
> You should have added the review tag you received.
>
> Applied. Thanks.

Oh, yes.  I would add the "Reviewed-by:" tag only if someone sends
this tag to me.

Like:
[0] https://lore.kernel.org/all/YnkvM5iuSuAOqBg+@lunn.ch/
[1] 
https://lore.kernel.org/all/20220510015521.2542096-1-wanjiabing@vivo.com/

If not explicitly stated, I am afraid to add some wrong "Reviewed-by:"
tags which might bother maintainers.

Thanks a lot for your priceless advice!

Wan Jiabing

Re: [PATCH v2] cpufreq: mediatek: Fix potential deadlock problem in mtk_cpufreq_set_target

Posted by Viresh Kumar 3 years, 9 months ago

On 10-05-22, 17:23, Jiabing Wan wrote:
> 
> 
> On 2022/5/10 17:12, Viresh Kumar wrote:
> > On 10-05-22, 17:05, Wan Jiabing wrote:
> > > Fix following coccichek error:
> > > ./drivers/cpufreq/mediatek-cpufreq.c:199:2-8: preceding lock on line
> > > ./drivers/cpufreq/mediatek-cpufreq.c:208:2-8: preceding lock on line
> > > 
> > > mutex_lock is acquired but not released before return.
> > > Use 'goto out' to help releasing the mutex_lock.
> > > 
> > > Fixes: c210063b40ac ("cpufreq: mediatek: Add opp notification support")
> > > Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
> > You should have added the review tag you received.
> > 
> > Applied. Thanks.
> 
> Oh, yes.  I would add the "Reviewed-by:" tag only if someone sends
> this tag to me.

Didn't you get this ?

https://lore.kernel.org/linux-mediatek/304e7eefbb57e9c938737b64fbb515201c7944b8.camel@mediatek.com/

Rex, are you subscribed to LKML ? You can't send an email there without
subscription. I don't see this email on LKML lore.

-- 
viresh

Re: [PATCH v2] cpufreq: mediatek: Fix potential deadlock problem in mtk_cpufreq_set_target

Posted by Jiabing Wan 3 years, 9 months ago


On 2022/5/10 17:28, Viresh Kumar wrote:
> On 10-05-22, 17:23, Jiabing Wan wrote:
>>
>> On 2022/5/10 17:12, Viresh Kumar wrote:
>>> On 10-05-22, 17:05, Wan Jiabing wrote:
>>>> Fix following coccichek error:
>>>> ./drivers/cpufreq/mediatek-cpufreq.c:199:2-8: preceding lock on line
>>>> ./drivers/cpufreq/mediatek-cpufreq.c:208:2-8: preceding lock on line
>>>>
>>>> mutex_lock is acquired but not released before return.
>>>> Use 'goto out' to help releasing the mutex_lock.
>>>>
>>>> Fixes: c210063b40ac ("cpufreq: mediatek: Add opp notification support")
>>>> Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
>>> You should have added the review tag you received.
>>>
>>> Applied. Thanks.
>> Oh, yes.  I would add the "Reviewed-by:" tag only if someone sends
>> this tag to me.
> Didn't you get this ?
>
> https://lore.kernel.org/linux-mediatek/304e7eefbb57e9c938737b64fbb515201c7944b8.camel@mediatek.com/

Oh, sorry! there might be some problem in my email-server.
I didn't get this email and I also didn't see this email on LKML lore.

So I missed this email.
Sorry for my mistake.

Wan Jiabing