pm_runtime_get_sync will increment pm usage counter even it
failed. Forgetting to putting operation will result in a
reference leak here.
A new function pm_runtime_resume_and_get is introduced in
[0] to keep usage counter balanced. So We fix the reference
leak by replacing it with new funtion.
[0] dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")
Fixes: 6cd225cc5d8a ("hwrng: exynos - add Samsung Exynos True RNG driver")
Reported-by: Hulk Robot <[email protected]>
Signed-off-by: Qinglang Miao <[email protected]>
---
drivers/char/hw_random/exynos-trng.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/char/hw_random/exynos-trng.c b/drivers/char/hw_random/exynos-trng.c
index 8e1fe3f8d..666246bc8 100644
--- a/drivers/char/hw_random/exynos-trng.c
+++ b/drivers/char/hw_random/exynos-trng.c
@@ -132,7 +132,7 @@ static int exynos_trng_probe(struct platform_device *pdev)
return PTR_ERR(trng->mem);
pm_runtime_enable(&pdev->dev);
- ret = pm_runtime_get_sync(&pdev->dev);
+ ret = pm_runtime_resume_and_get(&pdev->dev);
if (ret < 0) {
dev_err(&pdev->dev, "Could not get runtime PM.\n");
goto err_pm_get;
--
2.23.0
On Fri, Nov 27, 2020 at 05:44:46PM +0800, Qinglang Miao wrote:
> pm_runtime_get_sync will increment pm usage counter even it
> failed. Forgetting to putting operation will result in a
> reference leak here.
>
> A new function pm_runtime_resume_and_get is introduced in
> [0] to keep usage counter balanced. So We fix the reference
> leak by replacing it with new funtion.
>
> [0] dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")
Do not put such dependencies into the commit message - it does not bring
useful information to the history. Store it under '---' separator.
>
> Fixes: 6cd225cc5d8a ("hwrng: exynos - add Samsung Exynos True RNG driver")
> Reported-by: Hulk Robot <[email protected]>
> Signed-off-by: Qinglang Miao <[email protected]>
> ---
> drivers/char/hw_random/exynos-trng.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/char/hw_random/exynos-trng.c b/drivers/char/hw_random/exynos-trng.c
> index 8e1fe3f8d..666246bc8 100644
> --- a/drivers/char/hw_random/exynos-trng.c
> +++ b/drivers/char/hw_random/exynos-trng.c
> @@ -132,7 +132,7 @@ static int exynos_trng_probe(struct platform_device *pdev)
> return PTR_ERR(trng->mem);
>
> pm_runtime_enable(&pdev->dev);
> - ret = pm_runtime_get_sync(&pdev->dev);
> + ret = pm_runtime_resume_and_get(&pdev->dev);
This cannot be applied. Fix it by replacing err_clock label with this
one.
Best regards,
Krzysztof
It was <2020-11-27 pią 17:44>, when Qinglang Miao wrote:
> pm_runtime_get_sync will increment pm usage counter even it
> failed. Forgetting to putting operation will result in a
> reference leak here.
>
> A new function pm_runtime_resume_and_get is introduced in
> [0] to keep usage counter balanced. So We fix the reference
> leak by replacing it with new funtion.
>
> [0] dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")
>
> Fixes: 6cd225cc5d8a ("hwrng: exynos - add Samsung Exynos True RNG driver")
> Reported-by: Hulk Robot <[email protected]>
> Signed-off-by: Qinglang Miao <[email protected]>
> ---
> drivers/char/hw_random/exynos-trng.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/char/hw_random/exynos-trng.c b/drivers/char/hw_random/exynos-trng.c
> index 8e1fe3f8d..666246bc8 100644
> --- a/drivers/char/hw_random/exynos-trng.c
> +++ b/drivers/char/hw_random/exynos-trng.c
> @@ -132,7 +132,7 @@ static int exynos_trng_probe(struct platform_device *pdev)
> return PTR_ERR(trng->mem);
>
> pm_runtime_enable(&pdev->dev);
> - ret = pm_runtime_get_sync(&pdev->dev);
> + ret = pm_runtime_resume_and_get(&pdev->dev);
> if (ret < 0) {
> dev_err(&pdev->dev, "Could not get runtime PM.\n");
> goto err_pm_get;
Thanks. I suppose you may use the new function exynos_trng_resume(),
remove everything and leave only
return pm_runtime_resume_and_get(dev);
--
Łukasz Stelmach
Samsung R&D Institute Poland
Samsung Electronics
在 2020/11/27 17:44, Krzysztof Kozlowski 写道:
> On Fri, Nov 27, 2020 at 05:44:46PM +0800, Qinglang Miao wrote:
>> pm_runtime_get_sync will increment pm usage counter even it
>> failed. Forgetting to putting operation will result in a
>> reference leak here.
>>
>> A new function pm_runtime_resume_and_get is introduced in
>> [0] to keep usage counter balanced. So We fix the reference
>> leak by replacing it with new funtion.
>>
>> [0] dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")
>
> Do not put such dependencies into the commit message - it does not bring
> useful information to the history. Store it under '---' separator.
>
>>
>> Fixes: 6cd225cc5d8a ("hwrng: exynos - add Samsung Exynos True RNG driver")
>> Reported-by: Hulk Robot <[email protected]>
>> Signed-off-by: Qinglang Miao <[email protected]>
>> ---
>> drivers/char/hw_random/exynos-trng.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/char/hw_random/exynos-trng.c b/drivers/char/hw_random/exynos-trng.c
>> index 8e1fe3f8d..666246bc8 100644
>> --- a/drivers/char/hw_random/exynos-trng.c
>> +++ b/drivers/char/hw_random/exynos-trng.c
>> @@ -132,7 +132,7 @@ static int exynos_trng_probe(struct platform_device *pdev)
>> return PTR_ERR(trng->mem);
>>
>> pm_runtime_enable(&pdev->dev);
>> - ret = pm_runtime_get_sync(&pdev->dev);
>> + ret = pm_runtime_resume_and_get(&pdev->dev);
>
> This cannot be applied. Fix it by replacing err_clock label with this
> one. >
> Best regards,
> Krzysztof
>
> .
Hi Krzysztof,
I realize that there's a mistake in this patch through your reply.
There's two way to fix this one:
1) replace err_pm_get with err_clock label when pm_runtime_get_sync fails.
2) replace pm_runtime_get_sync with pm_runtime_resume_and_get and remove
redundant label(err_clock).
I take 2) on v2 for it makes codes more clearer in a way.
Thanks.
>
在 2020/11/27 22:26, Lukasz Stelmach 写道:
> It was <2020-11-27 pią 17:44>, when Qinglang Miao wrote:
>> pm_runtime_get_sync will increment pm usage counter even it
>> failed. Forgetting to putting operation will result in a
>> reference leak here.
>>
>> A new function pm_runtime_resume_and_get is introduced in
>> [0] to keep usage counter balanced. So We fix the reference
>> leak by replacing it with new funtion.
>>
>> [0] dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")
>>
>> Fixes: 6cd225cc5d8a ("hwrng: exynos - add Samsung Exynos True RNG driver")
>> Reported-by: Hulk Robot <[email protected]>
>> Signed-off-by: Qinglang Miao <[email protected]>
>> ---
>> drivers/char/hw_random/exynos-trng.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/char/hw_random/exynos-trng.c b/drivers/char/hw_random/exynos-trng.c
>> index 8e1fe3f8d..666246bc8 100644
>> --- a/drivers/char/hw_random/exynos-trng.c
>> +++ b/drivers/char/hw_random/exynos-trng.c
>> @@ -132,7 +132,7 @@ static int exynos_trng_probe(struct platform_device *pdev)
>> return PTR_ERR(trng->mem);
>>
>> pm_runtime_enable(&pdev->dev);
>> - ret = pm_runtime_get_sync(&pdev->dev);
>> + ret = pm_runtime_resume_and_get(&pdev->dev);
>> if (ret < 0) {
>> dev_err(&pdev->dev, "Could not get runtime PM.\n");
>> goto err_pm_get;
>
> Thanks. I suppose you may use the new function exynos_trng_resume(),
> remove everything and leave only
>
> return pm_runtime_resume_and_get(dev);
Hi, Lukasz
I sent a v2 on this one.
But I'm not really sure about what does 'remove everything' mean. for
example, should I remove exynos_trng_resume in this patch?
Thanks.
>