[PATCH 0/4 v2] firmware: stratix10-svc: Fix some error handling code

[PATCH 0/4 v2] firmware: stratix10-svc: Fix some error handling code

[Christophe JAILLET]

This serie was previously sent as a single patch.
After a comment from Dan Carpenter about an error handling path that could be
improved, I've looked deeper at the code and found other issues.

The previous patch corresponds to patch 3/4 in this serie.
This v2 takes Dan's comment into account and fix another resource leak.

Patch 1/4: svc_create_memory_pool returns an error code on error, not NULL 
Patch 2/4: undo a memremap on error path and remove funtion
Patch 3/4: improve error handling in the probe function
Patch 4/4: unrelated clean-up

Christophe JAILLET (4):
  firmware: stratix10-svc: Fix genpool creation error handling
  firmware: stratix10-svc: Unmap some previously memremap'ed memory
  firmware: stratix10-svc: Fix some error handling paths in
    'stratix10_svc_drv_probe()'
  firmware: stratix10-svc: Slighly simplify call

 drivers/firmware/stratix10-svc.c | 42 +++++++++++++++++++-------------
 1 file changed, 25 insertions(+), 17 deletions(-)

-- 
2.25.1

[PATCH 1/4 v2] firmware: stratix10-svc: Fix genpool creation error handling

[Christophe JAILLET]

'svc_create_memory_pool()' returns an error pointer on error, not NULL.
Fix the corresponding test and return value accordingly.

Move the genpool allocation after a few devm_kzalloc in order to ease
error handling.

Fixes: 7ca5ce896524 ("firmware: add Intel Stratix10 service layer driver")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
 drivers/firmware/stratix10-svc.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/firmware/stratix10-svc.c b/drivers/firmware/stratix10-svc.c
index d5f0769f3761..3a176e62754a 100644
--- a/drivers/firmware/stratix10-svc.c
+++ b/drivers/firmware/stratix10-svc.c
@@ -997,10 +997,6 @@ static int stratix10_svc_drv_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
-	genpool = svc_create_memory_pool(pdev, sh_memory);
-	if (!genpool)
-		return -ENOMEM;
-
 	/* allocate service controller and supporting channel */
 	controller = devm_kzalloc(dev, sizeof(*controller), GFP_KERNEL);
 	if (!controller)
@@ -1011,6 +1007,10 @@ static int stratix10_svc_drv_probe(struct platform_device *pdev)
 	if (!chans)
 		return -ENOMEM;
 
+	genpool = svc_create_memory_pool(pdev, sh_memory);
+	if (IS_ERR(genpool))
+		return PTR_ERR(genpool);
+
 	controller->dev = dev;
 	controller->num_chans = SVC_NUM_CHANNEL;
 	controller->num_active_client = 0;
-- 
2.25.1

Re: [PATCH 1/4 v2] firmware: stratix10-svc: Fix genpool creation error handling

[Markus Elfring]

> 'svc_create_memory_pool()' returns an error pointer on error, not NULL.

Such information is helpful.


> Fix the corresponding test and return value accordingly.
>
> Move the genpool allocation after a few devm_kzalloc in order to ease
> error handling.

How do you think about a wording variant like the following?

   Change description:
   * Use a check of the failure predicate which is documented for
     the svc_create_memory_pool() function in the same source file.

   * Move the genpool allocation behind a few devm_kzalloc() calls
     in order to ease exception handling.

Regards,
Markus

[PATCH 2/4 v2] firmware: stratix10-svc: Unmap some previously memremap'ed memory

[Christophe JAILLET]

In 'svc_create_memory_pool()' we memremap some memory. This has to be
undone in case of error and if the driver is removed.

The easiest way to do it is to use 'devm_memremap()'.

Fixes: 7ca5ce896524 ("firmware: add Intel Stratix10 service layer driver")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
 drivers/firmware/stratix10-svc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/firmware/stratix10-svc.c b/drivers/firmware/stratix10-svc.c
index 3a176e62754a..de5870f76c5e 100644
--- a/drivers/firmware/stratix10-svc.c
+++ b/drivers/firmware/stratix10-svc.c
@@ -631,7 +631,7 @@ svc_create_memory_pool(struct platform_device *pdev,
 	end = rounddown(sh_memory->addr + sh_memory->size, PAGE_SIZE);
 	paddr = begin;
 	size = end - begin;
-	va = memremap(paddr, size, MEMREMAP_WC);
+	va = devm_memremap(dev, paddr, size, MEMREMAP_WC);
 	if (!va) {
 		dev_err(dev, "fail to remap shared memory\n");
 		return ERR_PTR(-EINVAL);
-- 
2.25.1

Re: [PATCH 2/4 v2] firmware: stratix10-svc: Unmap some previously memremap'ed memory

[Greg KH]

On Wed, Apr 29, 2020 at 08:52:43AM +0200, Christophe JAILLET wrote:
> In 'svc_create_memory_pool()' we memremap some memory. This has to be
> undone in case of error and if the driver is removed.
> 
> The easiest way to do it is to use 'devm_memremap()'.
> 
> Fixes: 7ca5ce896524 ("firmware: add Intel Stratix10 service layer driver")
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> ---
>  drivers/firmware/stratix10-svc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/firmware/stratix10-svc.c b/drivers/firmware/stratix10-svc.c
> index 3a176e62754a..de5870f76c5e 100644
> --- a/drivers/firmware/stratix10-svc.c
> +++ b/drivers/firmware/stratix10-svc.c
> @@ -631,7 +631,7 @@ svc_create_memory_pool(struct platform_device *pdev,
>  	end = rounddown(sh_memory->addr + sh_memory->size, PAGE_SIZE);
>  	paddr = begin;
>  	size = end - begin;
> -	va = memremap(paddr, size, MEMREMAP_WC);
> +	va = devm_memremap(dev, paddr, size, MEMREMAP_WC);
>  	if (!va) {
>  		dev_err(dev, "fail to remap shared memory\n");
>  		return ERR_PTR(-EINVAL);

And there was no previous unmap happening when the pool was torn down
that now needs to be removed?

thanks,

greg k-h

Re: [PATCH 2/4 v2] firmware: stratix10-svc: Unmap some previously memremap'ed memory

[Christophe JAILLET]

Le 05/05/2020 à 16:43, Greg KH a écrit :
> On Wed, Apr 29, 2020 at 08:52:43AM +0200, Christophe JAILLET wrote:
>> In 'svc_create_memory_pool()' we memremap some memory. This has to be
>> undone in case of error and if the driver is removed.
>>
>> The easiest way to do it is to use 'devm_memremap()'.
>>
>> Fixes: 7ca5ce896524 ("firmware: add Intel Stratix10 service layer driver")
>> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
>> ---
>>   drivers/firmware/stratix10-svc.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/firmware/stratix10-svc.c b/drivers/firmware/stratix10-svc.c
>> index 3a176e62754a..de5870f76c5e 100644
>> --- a/drivers/firmware/stratix10-svc.c
>> +++ b/drivers/firmware/stratix10-svc.c
>> @@ -631,7 +631,7 @@ svc_create_memory_pool(struct platform_device *pdev,
>>   	end = rounddown(sh_memory->addr + sh_memory->size, PAGE_SIZE);
>>   	paddr = begin;
>>   	size = end - begin;
>> -	va = memremap(paddr, size, MEMREMAP_WC);
>> +	va = devm_memremap(dev, paddr, size, MEMREMAP_WC);
>>   	if (!va) {
>>   		dev_err(dev, "fail to remap shared memory\n");
>>   		return ERR_PTR(-EINVAL);
> And there was no previous unmap happening when the pool was torn down
> that now needs to be removed?

I don't think so, there is no memunmap call in 'stratix10-svc.c'

CJ

> thanks,
>
> greg k-h
>

[PATCH 3/4 v2] firmware: stratix10-svc: Fix some error handling paths in 'stratix10_svc_drv_probe()'

[Christophe JAILLET]

If an error occurs after calling 'svc_create_memory_pool()', the allocated
genpool should be destroyed with 'gen_pool_destroy()', as already done in
the remove function.

If an error occurs after calling 'kfifo_alloc()', the allocated memory
should be freed with 'kfifo_free()', as already done in the remove
function.

While at it, also move a 'platform_device_put()' call to the error handling
path.

Fixes: b5dc75c915cd ("firmware: stratix10-svc: extend svc to support new RSU features")
Fixes: 7ca5ce896524 ("firmware: add Intel Stratix10 service layer driver")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
 drivers/firmware/stratix10-svc.c | 26 ++++++++++++++++++--------
 1 file changed, 18 insertions(+), 8 deletions(-)

diff --git a/drivers/firmware/stratix10-svc.c b/drivers/firmware/stratix10-svc.c
index de5870f76c5e..739004398877 100644
--- a/drivers/firmware/stratix10-svc.c
+++ b/drivers/firmware/stratix10-svc.c
@@ -1024,7 +1024,7 @@ static int stratix10_svc_drv_probe(struct platform_device *pdev)
 	ret = kfifo_alloc(&controller->svc_fifo, fifo_size, GFP_KERNEL);
 	if (ret) {
 		dev_err(dev, "failed to allocate FIFO\n");
-		return ret;
+		goto err_destroy_pool;
 	}
 	spin_lock_init(&controller->svc_fifo_lock);
 
@@ -1043,24 +1043,34 @@ static int stratix10_svc_drv_probe(struct platform_device *pdev)
 
 	/* add svc client device(s) */
 	svc = devm_kzalloc(dev, sizeof(*svc), GFP_KERNEL);
-	if (!svc)
-		return -ENOMEM;
+	if (!svc) {
+		ret = -ENOMEM;
+		goto err_free_kfifo;
+	}
 
 	svc->stratix10_svc_rsu = platform_device_alloc(STRATIX10_RSU, 0);
 	if (!svc->stratix10_svc_rsu) {
 		dev_err(dev, "failed to allocate %s device\n", STRATIX10_RSU);
-		return -ENOMEM;
+		ret = -ENOMEM;
+		goto err_free_kfifo;
 	}
 
 	ret = platform_device_add(svc->stratix10_svc_rsu);
-	if (ret) {
-		platform_device_put(svc->stratix10_svc_rsu);
-		return ret;
-	}
+	if (ret)
+		goto put_platform;
+
 	dev_set_drvdata(dev, svc);
 
 	pr_info("Intel Service Layer Driver Initialized\n");
 
+	return 0;
+
+put_platform:
+	platform_device_put(svc->stratix10_svc_rsu);
+err_free_kfifo:
+	kfifo_free(&controller->svc_fifo);
+err_destroy_pool:
+	gen_pool_destroy(genpool);
 	return ret;
 }
 
-- 
2.25.1

Re: [PATCH 3/4 v2] firmware: stratix10-svc: Fix some error handling paths in stratix10_svc_drv_probe

[Markus Elfring]

> While at it, also move a 'platform_device_put()' call to the error handling path.

How do you think about to use the message “Complete exception handling
in stratix10_svc_drv_probe()” in the final commit subject?


…
> +++ b/drivers/firmware/stratix10-svc.c
…
> @@ -1043,24 +1043,34 @@  static int stratix10_svc_drv_probe(struct platform_device *pdev)
…
> +	return 0;
> +
> +put_platform:
> +	platform_device_put(svc->stratix10_svc_rsu);
> +err_free_kfifo:
…
>  	return ret;
>  }


Can the label “err_put_device” be more appropriate for the improved
function implementation?
(Or: Would you like to omit the prefix “err_” for these jump targets?)

Regards,
Markus

Re: [PATCH 3/4 v2] firmware: stratix10-svc: Fix some error handling paths in 'stratix10_svc_drv_prob

[Richard Gong]

Hi,

Similarly we need add error handling for controller and chans, something 
like below:

@@ -997,13 +997,17 @@ static int stratix10_svc_drv_probe(struct 
platform_device *pdev)

         /* allocate service controller and supporting channel */
         controller = devm_kzalloc(dev, sizeof(*controller), GFP_KERNEL);
-       if (!controller)
-               return -ENOMEM;
+       if (!controller) {
+               ret = -ENOMEM;
+               goto err_destroy_pool;
+       }

         chans = devm_kmalloc_array(dev, SVC_NUM_CHANNEL,
                                    sizeof(*chans), GFP_KERNEL | 
__GFP_ZERO);
-       if (!chans)
-               return -ENOMEM;
+       if (!chans) {
+               ret = -ENOMEM;
+               goto err_destroy_pool;
+       }

         controller->dev = dev;
         controller->num_chans = SVC_NUM_CHANNEL;

On 4/29/20 1:52 AM, Christophe JAILLET wrote:
> If an error occurs after calling 'svc_create_memory_pool()', the allocated
> genpool should be destroyed with 'gen_pool_destroy()', as already done in
> the remove function.
> 
> If an error occurs after calling 'kfifo_alloc()', the allocated memory
> should be freed with 'kfifo_free()', as already done in the remove
> function.
> 
> While at it, also move a 'platform_device_put()' call to the error handling
> path.
> 
> Fixes: b5dc75c915cd ("firmware: stratix10-svc: extend svc to support new RSU features")
> Fixes: 7ca5ce896524 ("firmware: add Intel Stratix10 service layer driver")
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> ---
>   drivers/firmware/stratix10-svc.c | 26 ++++++++++++++++++--------
>   1 file changed, 18 insertions(+), 8 deletions(-)
> 
I am fine with below changes.

> diff --git a/drivers/firmware/stratix10-svc.c b/drivers/firmware/stratix10-svc.c
> index de5870f76c5e..739004398877 100644
> --- a/drivers/firmware/stratix10-svc.c
> +++ b/drivers/firmware/stratix10-svc.c
> @@ -1024,7 +1024,7 @@ static int stratix10_svc_drv_probe(struct platform_device *pdev)
>   	ret = kfifo_alloc(&controller->svc_fifo, fifo_size, GFP_KERNEL);
>   	if (ret) {
>   		dev_err(dev, "failed to allocate FIFO\n");
> -		return ret;
> +		goto err_destroy_pool;
>   	}
>   	spin_lock_init(&controller->svc_fifo_lock);
>   
> @@ -1043,24 +1043,34 @@ static int stratix10_svc_drv_probe(struct platform_device *pdev)
>   
>   	/* add svc client device(s) */
>   	svc = devm_kzalloc(dev, sizeof(*svc), GFP_KERNEL);
> -	if (!svc)
> -		return -ENOMEM;
> +	if (!svc) {
> +		ret = -ENOMEM;
> +		goto err_free_kfifo;
> +	}
>   
>   	svc->stratix10_svc_rsu = platform_device_alloc(STRATIX10_RSU, 0);
>   	if (!svc->stratix10_svc_rsu) {
>   		dev_err(dev, "failed to allocate %s device\n", STRATIX10_RSU);
> -		return -ENOMEM;
> +		ret = -ENOMEM;
> +		goto err_free_kfifo;
>   	}
>   
>   	ret = platform_device_add(svc->stratix10_svc_rsu);
> -	if (ret) {
> -		platform_device_put(svc->stratix10_svc_rsu);
> -		return ret;
> -	}
> +	if (ret)
> +		goto put_platform;
> +
>   	dev_set_drvdata(dev, svc);
>   
>   	pr_info("Intel Service Layer Driver Initialized\n");
>   
> +	return 0;
> +
> +put_platform:
> +	platform_device_put(svc->stratix10_svc_rsu);
> +err_free_kfifo:
> +	kfifo_free(&controller->svc_fifo);
> +err_destroy_pool:
> +	gen_pool_destroy(genpool);
>   	return ret;
>   }
>   
> 
Regards,
Richard

Re: [PATCH 3/4 v2] firmware: stratix10-svc: Fix some error handling paths in 'stratix10_svc_drv_prob

[Christophe JAILLET]

Le 05/05/2020 à 16:02, Richard Gong a écrit :
> Hi,
>
> Similarly we need add error handling for controller and chans, 
> something like below:
>
> @@ -997,13 +997,17 @@ static int stratix10_svc_drv_probe(struct 
> platform_device *pdev)
>
>         /* allocate service controller and supporting channel */
>         controller = devm_kzalloc(dev, sizeof(*controller), GFP_KERNEL);
> -       if (!controller)
> -               return -ENOMEM;
> +       if (!controller) {
> +               ret = -ENOMEM;
> +               goto err_destroy_pool;
> +       }
>
>         chans = devm_kmalloc_array(dev, SVC_NUM_CHANNEL,
>                                    sizeof(*chans), GFP_KERNEL | 
> __GFP_ZERO);
> -       if (!chans)
> -               return -ENOMEM;
> +       if (!chans) {
> +               ret = -ENOMEM;
> +               goto err_destroy_pool;
> +       }
>
>         controller->dev = dev;
>         controller->num_chans = SVC_NUM_CHANNEL;
>
Hi,

This is addressed in patch 1/4.
It moves 'svc_create_memory_pool' after these 2 allocations in order to 
avoid the goto.

I'll send a V3 in only 1 patch, as you proposed, it will ease review.

CJ


> On 4/29/20 1:52 AM, Christophe JAILLET wrote:
>> If an error occurs after calling 'svc_create_memory_pool()', the 
>> allocated
>> genpool should be destroyed with 'gen_pool_destroy()', as already 
>> done in
>> the remove function.
>>
>> If an error occurs after calling 'kfifo_alloc()', the allocated memory
>> should be freed with 'kfifo_free()', as already done in the remove
>> function.
>>
>> While at it, also move a 'platform_device_put()' call to the error 
>> handling
>> path.
>>
>> Fixes: b5dc75c915cd ("firmware: stratix10-svc: extend svc to support 
>> new RSU features")
>> Fixes: 7ca5ce896524 ("firmware: add Intel Stratix10 service layer 
>> driver")
>> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
>> ---
>>   drivers/firmware/stratix10-svc.c | 26 ++++++++++++++++++--------
>>   1 file changed, 18 insertions(+), 8 deletions(-)
>>
> I am fine with below changes.
>
>> diff --git a/drivers/firmware/stratix10-svc.c 
>> b/drivers/firmware/stratix10-svc.c
>> index de5870f76c5e..739004398877 100644
>> --- a/drivers/firmware/stratix10-svc.c
>> +++ b/drivers/firmware/stratix10-svc.c
>> @@ -1024,7 +1024,7 @@ static int stratix10_svc_drv_probe(struct 
>> platform_device *pdev)
>>       ret = kfifo_alloc(&controller->svc_fifo, fifo_size, GFP_KERNEL);
>>       if (ret) {
>>           dev_err(dev, "failed to allocate FIFO\n");
>> -        return ret;
>> +        goto err_destroy_pool;
>>       }
>>       spin_lock_init(&controller->svc_fifo_lock);
>>   @@ -1043,24 +1043,34 @@ static int stratix10_svc_drv_probe(struct 
>> platform_device *pdev)
>>         /* add svc client device(s) */
>>       svc = devm_kzalloc(dev, sizeof(*svc), GFP_KERNEL);
>> -    if (!svc)
>> -        return -ENOMEM;
>> +    if (!svc) {
>> +        ret = -ENOMEM;
>> +        goto err_free_kfifo;
>> +    }
>>         svc->stratix10_svc_rsu = platform_device_alloc(STRATIX10_RSU, 
>> 0);
>>       if (!svc->stratix10_svc_rsu) {
>>           dev_err(dev, "failed to allocate %s device\n", STRATIX10_RSU);
>> -        return -ENOMEM;
>> +        ret = -ENOMEM;
>> +        goto err_free_kfifo;
>>       }
>>         ret = platform_device_add(svc->stratix10_svc_rsu);
>> -    if (ret) {
>> -        platform_device_put(svc->stratix10_svc_rsu);
>> -        return ret;
>> -    }
>> +    if (ret)
>> +        goto put_platform;
>> +
>>       dev_set_drvdata(dev, svc);
>>         pr_info("Intel Service Layer Driver Initialized\n");
>>   +    return 0;
>> +
>> +put_platform:
>> +    platform_device_put(svc->stratix10_svc_rsu);
>> +err_free_kfifo:
>> +    kfifo_free(&controller->svc_fifo);
>> +err_destroy_pool:
>> +    gen_pool_destroy(genpool);
>>       return ret;
>>   }
>>
> Regards,
> Richard
>

[PATCH V3] firmware: stratix10-svc: Fix some error handling code

[Christophe JAILLET]

Fix several error handling issues:
   - In 'svc_create_memory_pool()' we memremap some memory. This has to be
undone in case of error and if the driver is removed.
The easiest way to do it is to use 'devm_memremap()'.

  - 'svc_create_memory_pool()' returns an error pointer on error, not NULL.
In 'stratix10_svc_drv_probe()', fix the corresponding test and return value
accordingly.

  - Move the genpool allocation after a few devm_kzalloc in order to ease
error handling. (some call to 'gen_pool_destroy()' were missing)

   - If an error occurs after calling 'svc_create_memory_pool()', the
allocated genpool should be destroyed with 'gen_pool_destroy()', as
already done in the remove function.
Add an error handling path for that

   - If an error occurs after calling 'kfifo_alloc()', the allocated
memory should be freed with 'kfifo_free()', as already done in the remove
function.
Add an error handling path for that


While at it, do some clean-up:
   - Use 'devm_kcalloc()' instead of 'devm_kmalloc_array(... __GFP_ZERO)'

   - move a 'platform_device_put()' call to the new error handling path.

   - In 'stratix10_svc_drv_remove()', 'ctrl->genpool' can not be NULL, so
axe a useless test in the remove function.

Fixes: b5dc75c915cd ("firmware: stratix10-svc: extend svc to support new RSU features")
Fixes: 7ca5ce896524 ("firmware: add Intel Stratix10 service layer driver")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
v2: takes Dan's comment into account and fix another resource leak.
v3: merge the previous 4 patches in a single one to ease review
---
 drivers/firmware/stratix10-svc.c | 42 +++++++++++++++++++-------------
 1 file changed, 25 insertions(+), 17 deletions(-)

diff --git a/drivers/firmware/stratix10-svc.c b/drivers/firmware/stratix10-svc.c
index e0db8dbfc9d1..90f7d68a2473 100644
--- a/drivers/firmware/stratix10-svc.c
+++ b/drivers/firmware/stratix10-svc.c
@@ -605,7 +605,7 @@ svc_create_memory_pool(struct platform_device *pdev,
 	end = rounddown(sh_memory->addr + sh_memory->size, PAGE_SIZE);
 	paddr = begin;
 	size = end - begin;
-	va = memremap(paddr, size, MEMREMAP_WC);
+	va = devm_memremap(dev, paddr, size, MEMREMAP_WC);
 	if (!va) {
 		dev_err(dev, "fail to remap shared memory\n");
 		return ERR_PTR(-EINVAL);
@@ -971,20 +971,19 @@ static int stratix10_svc_drv_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
-	genpool = svc_create_memory_pool(pdev, sh_memory);
-	if (!genpool)
-		return -ENOMEM;
-
 	/* allocate service controller and supporting channel */
 	controller = devm_kzalloc(dev, sizeof(*controller), GFP_KERNEL);
 	if (!controller)
 		return -ENOMEM;
 
-	chans = devm_kmalloc_array(dev, SVC_NUM_CHANNEL,
-				   sizeof(*chans), GFP_KERNEL | __GFP_ZERO);
+	chans = devm_kcalloc(dev, SVC_NUM_CHANNEL, sizeof(*chans), GFP_KERNEL);
 	if (!chans)
 		return -ENOMEM;
 
+	genpool = svc_create_memory_pool(pdev, sh_memory);
+	if (IS_ERR(genpool))
+		return PTR_ERR(genpool);
+
 	controller->dev = dev;
 	controller->num_chans = SVC_NUM_CHANNEL;
 	controller->num_active_client = 0;
@@ -998,7 +997,7 @@ static int stratix10_svc_drv_probe(struct platform_device *pdev)
 	ret = kfifo_alloc(&controller->svc_fifo, fifo_size, GFP_KERNEL);
 	if (ret) {
 		dev_err(dev, "failed to allocate FIFO\n");
-		return ret;
+		goto err_destroy_pool;
 	}
 	spin_lock_init(&controller->svc_fifo_lock);
 
@@ -1017,24 +1016,34 @@ static int stratix10_svc_drv_probe(struct platform_device *pdev)
 
 	/* add svc client device(s) */
 	svc = devm_kzalloc(dev, sizeof(*svc), GFP_KERNEL);
-	if (!svc)
-		return -ENOMEM;
+	if (!svc) {
+		ret = -ENOMEM;
+		goto err_free_kfifo;
+	}
 
 	svc->stratix10_svc_rsu = platform_device_alloc(STRATIX10_RSU, 0);
 	if (!svc->stratix10_svc_rsu) {
 		dev_err(dev, "failed to allocate %s device\n", STRATIX10_RSU);
-		return -ENOMEM;
+		ret = -ENOMEM;
+		goto err_free_kfifo;
 	}
 
 	ret = platform_device_add(svc->stratix10_svc_rsu);
-	if (ret) {
-		platform_device_put(svc->stratix10_svc_rsu);
-		return ret;
-	}
+	if (ret)
+		goto put_platform;
+
 	dev_set_drvdata(dev, svc);
 
 	pr_info("Intel Service Layer Driver Initialized\n");
 
+	return 0;
+
+put_platform:
+	platform_device_put(svc->stratix10_svc_rsu);
+err_free_kfifo:
+	kfifo_free(&controller->svc_fifo);
+err_destroy_pool:
+	gen_pool_destroy(genpool);
 	return ret;
 }
 
@@ -1050,8 +1059,7 @@ static int stratix10_svc_drv_remove(struct platform_device *pdev)
 		kthread_stop(ctrl->task);
 		ctrl->task = NULL;
 	}
-	if (ctrl->genpool)
-		gen_pool_destroy(ctrl->genpool);
+	gen_pool_destroy(ctrl->genpool);
 	list_del(&ctrl->node);
 
 	return 0;
-- 
2.25.1

Re: [PATCH V3] firmware: stratix10-svc: Fix some error handling code

[Greg KH]

On Fri, Jun 26, 2020 at 09:37:20PM +0200, Christophe JAILLET wrote:
> Fix several error handling issues:

<snip>

When you have to list a bunch of different things you do in a driver,
that's a huge hint this needs to be broken up into multiple patches.

Please do that here.

thanks,

greg k-h

Re: [PATCH V3] firmware: stratix10-svc: Fix some error handling code

[Greg KH]

On Fri, Jun 26, 2020 at 09:37:20PM +0200, Christophe JAILLET wrote:
> ---
> v2: takes Dan's comment into account and fix another resource leak.
> v3: merge the previous 4 patches in a single one to ease review


No, 4 small patches are _MUCH_ easier to review than one larger one that
mixes everything together.  Who told you to put them together?

Re: [PATCH V3] firmware: stratix10-svc: Fix some error handling code

[Marion & Christophe JAILLET]

Le 27/06/2020 à 07:15, Greg KH a écrit :
> On Fri, Jun 26, 2020 at 09:37:20PM +0200, Christophe JAILLET wrote:
>> ---
>> v2: takes Dan's comment into account and fix another resource leak.
>> v3: merge the previous 4 patches in a single one to ease review
>
> No, 4 small patches are _MUCH_ easier to review than one larger one that
> mixes everything together.  Who told you to put them together?

The cover letter of v2 serie can be found at [1].
The request for merging them in 1 patch is in [2].

V3, should be the same as v2, but all in one.

[1]: https://lkml.org/lkml/2020/4/29/77
[2]: https://lkml.org/lkml/2020/5/5/541

CJ

Re: [PATCH V3] firmware: stratix10-svc: Fix some error handling code

[Greg KH]

On Sat, Jun 27, 2020 at 09:31:27AM +0200, Marion & Christophe JAILLET wrote:
> 
> Le 27/06/2020 à 07:15, Greg KH a écrit :
> > On Fri, Jun 26, 2020 at 09:37:20PM +0200, Christophe JAILLET wrote:
> > > ---
> > > v2: takes Dan's comment into account and fix another resource leak.
> > > v3: merge the previous 4 patches in a single one to ease review
> > 
> > No, 4 small patches are _MUCH_ easier to review than one larger one that
> > mixes everything together.  Who told you to put them together?
> 
> The cover letter of v2 serie can be found at [1].
> The request for merging them in 1 patch is in [2].
> 
> V3, should be the same as v2, but all in one.
> 
> [1]: https://lkml.org/lkml/2020/4/29/77
> [2]: https://lkml.org/lkml/2020/5/5/541

Please use lore.kernel.org in the future, we don't control lkml.org and
can't rely on it.

Anyway, that request was incorrect, sorry.  Please keep them split up in
a way that makes it easy to review.

Which would you want to read if you had to review hundreds of patches?

thanks,

greg k-h

[PATCH 4/4 v2] firmware: stratix10-svc: Slightly simplify code

[Christophe JAILLET]

Replace 'devm_kmalloc_array(... | __GFP_ZERO)' with the equivalent and
shorter 'devm_kcalloc(...)'.

'ctrl->genpool' can not be NULL, so axe a useless test in the remove
function.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
 drivers/firmware/stratix10-svc.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/firmware/stratix10-svc.c b/drivers/firmware/stratix10-svc.c
index 739004398877..c228337cb0a1 100644
--- a/drivers/firmware/stratix10-svc.c
+++ b/drivers/firmware/stratix10-svc.c
@@ -1002,8 +1002,7 @@ static int stratix10_svc_drv_probe(struct platform_device *pdev)
 	if (!controller)
 		return -ENOMEM;
 
-	chans = devm_kmalloc_array(dev, SVC_NUM_CHANNEL,
-				   sizeof(*chans), GFP_KERNEL | __GFP_ZERO);
+	chans = devm_kcalloc(dev, SVC_NUM_CHANNEL, sizeof(*chans), GFP_KERNEL);
 	if (!chans)
 		return -ENOMEM;
 
@@ -1086,8 +1085,7 @@ static int stratix10_svc_drv_remove(struct platform_device *pdev)
 		kthread_stop(ctrl->task);
 		ctrl->task = NULL;
 	}
-	if (ctrl->genpool)
-		gen_pool_destroy(ctrl->genpool);
+	gen_pool_destroy(ctrl->genpool);
 	list_del(&ctrl->node);
 
 	return 0;
-- 
2.25.1

Re: [PATCH 4/4 v2] firmware: stratix10-svc: Slightly simplify code

[Markus Elfring]

> Replace 'devm_kmalloc_array(... | __GFP_ZERO)' with the equivalent and
> shorter 'devm_kcalloc(...)'.
>
> 'ctrl->genpool' can not be NULL, so axe a useless test in the remove
> function.

I would find it clearer to integrate also such small source code improvements
by separate patches.

Regards,
Markus

Re: [PATCH 4/4 v2] firmware: stratix10-svc: Slightly simplify code

[Richard Gong]

Hi,

On 4/29/20 1:52 AM, Christophe JAILLET wrote:
> Replace 'devm_kmalloc_array(... | __GFP_ZERO)' with the equivalent and
> shorter 'devm_kcalloc(...)'.
> 
It doesn't make much sense.
Actually devm_kcalloc returns devm_kmalloc_array(.., flag | __GFP_ZERO).

> 'ctrl->genpool' can not be NULL, so axe a useless test in the remove
> function.
> 
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> ---
>   drivers/firmware/stratix10-svc.c | 6 ++----
>   1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/firmware/stratix10-svc.c b/drivers/firmware/stratix10-svc.c
> index 739004398877..c228337cb0a1 100644
> --- a/drivers/firmware/stratix10-svc.c
> +++ b/drivers/firmware/stratix10-svc.c
> @@ -1002,8 +1002,7 @@ static int stratix10_svc_drv_probe(struct platform_device *pdev)
>   	if (!controller)
>   		return -ENOMEM;
>   
> -	chans = devm_kmalloc_array(dev, SVC_NUM_CHANNEL,
> -				   sizeof(*chans), GFP_KERNEL | __GFP_ZERO);
> +	chans = devm_kcalloc(dev, SVC_NUM_CHANNEL, sizeof(*chans), GFP_KERNEL);
>   	if (!chans)
>   		return -ENOMEM;
>   
> @@ -1086,8 +1085,7 @@ static int stratix10_svc_drv_remove(struct platform_device *pdev)
>   		kthread_stop(ctrl->task);
>   		ctrl->task = NULL;
>   	}
> -	if (ctrl->genpool)
> -		gen_pool_destroy(ctrl->genpool);
> +	gen_pool_destroy(ctrl->genpool);
>   	list_del(&ctrl->node);
>   
>   	return 0;
> 

Regards,
Richard

Re: [PATCH 4/4 v2] firmware: stratix10-svc: Slightly simplify code

[Christophe JAILLET]

Le 01/05/2020 à 17:40, Richard Gong a écrit :
> Hi,
>
> On 4/29/20 1:52 AM, Christophe JAILLET wrote:
>> Replace 'devm_kmalloc_array(... | __GFP_ZERO)' with the equivalent and
>> shorter 'devm_kcalloc(...)'.
>>
> It doesn't make much sense.
> Actually devm_kcalloc returns devm_kmalloc_array(.., flag | __GFP_ZERO).
>
The only goal is to have a sightly less verbose code.
This saves one line of code and there is no need to wonder why we 
explicitly pass __GFP_ZERO to kmalloc_array.

Mostly a matter of taste.

'devm_kcalloc' is inlined, so the binary should be exactly the same.

CJ

>> 'ctrl->genpool' can not be NULL, so axe a useless test in the remove
>> function.
>>
>> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
>> ---
>>   drivers/firmware/stratix10-svc.c | 6 ++----
>>   1 file changed, 2 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/firmware/stratix10-svc.c 
>> b/drivers/firmware/stratix10-svc.c
>> index 739004398877..c228337cb0a1 100644
>> --- a/drivers/firmware/stratix10-svc.c
>> +++ b/drivers/firmware/stratix10-svc.c
>> @@ -1002,8 +1002,7 @@ static int stratix10_svc_drv_probe(struct 
>> platform_device *pdev)
>>       if (!controller)
>>           return -ENOMEM;
>>   -    chans = devm_kmalloc_array(dev, SVC_NUM_CHANNEL,
>> -                   sizeof(*chans), GFP_KERNEL | __GFP_ZERO);
>> +    chans = devm_kcalloc(dev, SVC_NUM_CHANNEL, sizeof(*chans), 
>> GFP_KERNEL);
>>       if (!chans)
>>           return -ENOMEM;
>>   @@ -1086,8 +1085,7 @@ static int stratix10_svc_drv_remove(struct 
>> platform_device *pdev)
>>           kthread_stop(ctrl->task);
>>           ctrl->task = NULL;
>>       }
>> -    if (ctrl->genpool)
>> -        gen_pool_destroy(ctrl->genpool);
>> +    gen_pool_destroy(ctrl->genpool);
>>       list_del(&ctrl->node);
>>         return 0;
>>
>
> Regards,
> Richard
>

Re: [PATCH 4/4 v2] firmware: stratix10-svc: Slightly simplify code

[Richard Gong]

Hi,

On 5/1/20 10:48 AM, Christophe JAILLET wrote:
> Le 01/05/2020 à 17:40, Richard Gong a écrit :
>> Hi,
>>
>> On 4/29/20 1:52 AM, Christophe JAILLET wrote:
>>> Replace 'devm_kmalloc_array(... | __GFP_ZERO)' with the equivalent and
>>> shorter 'devm_kcalloc(...)'.
>>>
>> It doesn't make much sense.
>> Actually devm_kcalloc returns devm_kmalloc_array(.., flag | __GFP_ZERO).
>>
> The only goal is to have a sightly less verbose code.
> This saves one line of code and there is no need to wonder why we 
> explicitly pass __GFP_ZERO to kmalloc_array.
> 
> Mostly a matter of taste.
I prefer this part remain unchanged.

Regards,
Richard

> 
> 'devm_kcalloc' is inlined, so the binary should be exactly the same. >
> CJ
> 
>>> 'ctrl->genpool' can not be NULL, so axe a useless test in the remove
>>> function.
>>>
>>> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
>>> ---
>>>   drivers/firmware/stratix10-svc.c | 6 ++----
>>>   1 file changed, 2 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/drivers/firmware/stratix10-svc.c 
>>> b/drivers/firmware/stratix10-svc.c
>>> index 739004398877..c228337cb0a1 100644
>>> --- a/drivers/firmware/stratix10-svc.c
>>> +++ b/drivers/firmware/stratix10-svc.c
>>> @@ -1002,8 +1002,7 @@ static int stratix10_svc_drv_probe(struct 
>>> platform_device *pdev)
>>>       if (!controller)
>>>           return -ENOMEM;
>>>   -    chans = devm_kmalloc_array(dev, SVC_NUM_CHANNEL,
>>> -                   sizeof(*chans), GFP_KERNEL | __GFP_ZERO);
>>> +    chans = devm_kcalloc(dev, SVC_NUM_CHANNEL, sizeof(*chans), 
>>> GFP_KERNEL);
>>>       if (!chans)
>>>           return -ENOMEM;
>>>   @@ -1086,8 +1085,7 @@ static int stratix10_svc_drv_remove(struct 
>>> platform_device *pdev)
>>>           kthread_stop(ctrl->task);
>>>           ctrl->task = NULL;
>>>       }
>>> -    if (ctrl->genpool)
>>> -        gen_pool_destroy(ctrl->genpool);
>>> +    gen_pool_destroy(ctrl->genpool);
>>>       list_del(&ctrl->node);
>>>         return 0;
>>>
>>
>> Regards,
>> Richard
>>
> 

Re: [PATCH 4/4 v2] firmware: stratix10-svc: Slightly simplify code

[Christophe JAILLET]

Le 01/05/2020 à 18:55, Richard Gong a écrit :
> Hi,
>
> On 5/1/20 10:48 AM, Christophe JAILLET wrote:
>> Le 01/05/2020 à 17:40, Richard Gong a écrit :
>>> Hi,
>>>
>>> On 4/29/20 1:52 AM, Christophe JAILLET wrote:
>>>> Replace 'devm_kmalloc_array(... | __GFP_ZERO)' with the equivalent and
>>>> shorter 'devm_kcalloc(...)'.
>>>>
>>> It doesn't make much sense.
>>> Actually devm_kcalloc returns devm_kmalloc_array(.., flag | 
>>> __GFP_ZERO).
>>>
>> The only goal is to have a sightly less verbose code.
>> This saves one line of code and there is no need to wonder why we 
>> explicitly pass __GFP_ZERO to kmalloc_array.
>>
>> Mostly a matter of taste.
> I prefer this part remain unchanged.
>

The easiest would be just to ignore this patch entirely but if you need 
a v3 for the series, could you tell me if you have any comments on the 3 
other patches?

CJ


> Regards,
> Richard
>
>>
>> 'devm_kcalloc' is inlined, so the binary should be exactly the same. >
>> CJ
>>
>>>> 'ctrl->genpool' can not be NULL, so axe a useless test in the remove
>>>> function.
>>>>
>>>> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
>>>> ---
>>>>   drivers/firmware/stratix10-svc.c | 6 ++----
>>>>   1 file changed, 2 insertions(+), 4 deletions(-)
>>>>
>>>> diff --git a/drivers/firmware/stratix10-svc.c 
>>>> b/drivers/firmware/stratix10-svc.c
>>>> index 739004398877..c228337cb0a1 100644
>>>> --- a/drivers/firmware/stratix10-svc.c
>>>> +++ b/drivers/firmware/stratix10-svc.c
>>>> @@ -1002,8 +1002,7 @@ static int stratix10_svc_drv_probe(struct 
>>>> platform_device *pdev)
>>>>       if (!controller)
>>>>           return -ENOMEM;
>>>>   -    chans = devm_kmalloc_array(dev, SVC_NUM_CHANNEL,
>>>> -                   sizeof(*chans), GFP_KERNEL | __GFP_ZERO);
>>>> +    chans = devm_kcalloc(dev, SVC_NUM_CHANNEL, sizeof(*chans), 
>>>> GFP_KERNEL);
>>>>       if (!chans)
>>>>           return -ENOMEM;
>>>>   @@ -1086,8 +1085,7 @@ static int stratix10_svc_drv_remove(struct 
>>>> platform_device *pdev)
>>>>           kthread_stop(ctrl->task);
>>>>           ctrl->task = NULL;
>>>>       }
>>>> -    if (ctrl->genpool)
>>>> -        gen_pool_destroy(ctrl->genpool);
>>>> +    gen_pool_destroy(ctrl->genpool);
>>>>       list_del(&ctrl->node);
>>>>         return 0;
>>>>
>>>
>>> Regards,
>>> Richard
>>>
>>
>

Re: [PATCH 4/4 v2] firmware: stratix10-svc: Slightly simplify code

[Richard Gong]

Hi,

On 5/2/20 3:49 AM, Christophe JAILLET wrote:
> Le 01/05/2020 à 18:55, Richard Gong a écrit :
>> Hi,
>>
>> On 5/1/20 10:48 AM, Christophe JAILLET wrote:
>>> Le 01/05/2020 à 17:40, Richard Gong a écrit :
>>>> Hi,
>>>>
>>>> On 4/29/20 1:52 AM, Christophe JAILLET wrote:
>>>>> Replace 'devm_kmalloc_array(... | __GFP_ZERO)' with the equivalent and
>>>>> shorter 'devm_kcalloc(...)'.
>>>>>
>>>> It doesn't make much sense.
>>>> Actually devm_kcalloc returns devm_kmalloc_array(.., flag | 
>>>> __GFP_ZERO).
>>>>
>>> The only goal is to have a sightly less verbose code.
>>> This saves one line of code and there is no need to wonder why we 
>>> explicitly pass __GFP_ZERO to kmalloc_array.
>>>
>>> Mostly a matter of taste.
>> I prefer this part remain unchanged.
>>
> 
> The easiest would be just to ignore this patch entirely
Yes, please.
  but if you need
> a v3 for the series, could you tell me if you have any comments on the 3 
> other patches?
> 
I added some comments in your patch #3, also recommend putting all 
changes in one patch.

Regards,
Richard

> CJ
> 
> 
>> Regards,
>> Richard
>>
>>>
>>> 'devm_kcalloc' is inlined, so the binary should be exactly the same. >
>>> CJ
>>>
>>>>> 'ctrl->genpool' can not be NULL, so axe a useless test in the remove
>>>>> function.
>>>>>
>>>>> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
>>>>> ---
>>>>>   drivers/firmware/stratix10-svc.c | 6 ++----
>>>>>   1 file changed, 2 insertions(+), 4 deletions(-)
>>>>>
>>>>> diff --git a/drivers/firmware/stratix10-svc.c 
>>>>> b/drivers/firmware/stratix10-svc.c
>>>>> index 739004398877..c228337cb0a1 100644
>>>>> --- a/drivers/firmware/stratix10-svc.c
>>>>> +++ b/drivers/firmware/stratix10-svc.c
>>>>> @@ -1002,8 +1002,7 @@ static int stratix10_svc_drv_probe(struct 
>>>>> platform_device *pdev)
>>>>>       if (!controller)
>>>>>           return -ENOMEM;
>>>>>   -    chans = devm_kmalloc_array(dev, SVC_NUM_CHANNEL,
>>>>> -                   sizeof(*chans), GFP_KERNEL | __GFP_ZERO);
>>>>> +    chans = devm_kcalloc(dev, SVC_NUM_CHANNEL, sizeof(*chans), 
>>>>> GFP_KERNEL);
>>>>>       if (!chans)
>>>>>           return -ENOMEM;
>>>>>   @@ -1086,8 +1085,7 @@ static int stratix10_svc_drv_remove(struct 
>>>>> platform_device *pdev)
>>>>>           kthread_stop(ctrl->task);
>>>>>           ctrl->task = NULL;
>>>>>       }
>>>>> -    if (ctrl->genpool)
>>>>> -        gen_pool_destroy(ctrl->genpool);
>>>>> +    gen_pool_destroy(ctrl->genpool);
>>>>>       list_del(&ctrl->node);
>>>>>         return 0;
>>>>>
>>>>
>>>> Regards,
>>>> Richard
>>>>
>>>
>>
> 

Re: [PATCH 4/4 v2] firmware: stratix10-svc: Slightly simplify code

[Dan Carpenter]

On Fri, May 01, 2020 at 10:40:20AM -0500, Richard Gong wrote:
> Hi,
> 
> On 4/29/20 1:52 AM, Christophe JAILLET wrote:
> > Replace 'devm_kmalloc_array(... | __GFP_ZERO)' with the equivalent and
> > shorter 'devm_kcalloc(...)'.
> > 
> It doesn't make much sense.
> Actually devm_kcalloc returns devm_kmalloc_array(.., flag | __GFP_ZERO).
> 

devm_kcalloc() is better style and easier to read.  I was just reading
a bunch of AMD code that does this and I almost complained to them
that devm_kmalloc_array() doesn't zero the memory so they were freeing
uninitialized pointers.

regards,
dan carpenter