diff mbox series

[v2] drm/panthor: Fix couple of NULL vs IS_ERR() bugs

Message ID 20240402134709.1706323-1-harshit.m.mogalapalli@oracle.com (mailing list archive)
State New, archived
Headers show
Series [v2] drm/panthor: Fix couple of NULL vs IS_ERR() bugs | expand

Commit Message

Harshit Mogalapalli April 2, 2024, 1:47 p.m. UTC
1. The devm_drm_dev_alloc() function returns error pointers.
   Update the error handling to check for error pointers instead of NULL.
2. Currently panthor_vm_get_heap_pool() returns both ERR_PTR() and
   NULL(when create is false and if there is no poool attached to the
   VM)
	- Change the function to return error pointers, when pool is
	  NULL return -ENOENT
	- Also handle the callers to check for IS_ERR() on failure.

Fixes: 4bdca1150792 ("drm/panthor: Add the driver frontend block")
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
---
This is spotted by smatch and the patch is only compile tested

v1->v2: Fix the function panthor_vm_get_heap_pool() to only return error
pointers and handle the caller sites [Suggested by Boris Brezillon]
	- Also merge these IS_ERR() vs NULL bugs into same patch
---
 drivers/gpu/drm/panthor/panthor_drv.c   | 6 +++---
 drivers/gpu/drm/panthor/panthor_mmu.c   | 2 ++
 drivers/gpu/drm/panthor/panthor_sched.c | 2 +-
 3 files changed, 6 insertions(+), 4 deletions(-)

Comments

Boris Brezillon April 2, 2024, 2:02 p.m. UTC | #1
On Tue,  2 Apr 2024 06:47:08 -0700
Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> wrote:

> 1. The devm_drm_dev_alloc() function returns error pointers.
>    Update the error handling to check for error pointers instead of NULL.
> 2. Currently panthor_vm_get_heap_pool() returns both ERR_PTR() and
>    NULL(when create is false and if there is no poool attached to the
>    VM)
> 	- Change the function to return error pointers, when pool is
> 	  NULL return -ENOENT
> 	- Also handle the callers to check for IS_ERR() on failure.
> 
> Fixes: 4bdca1150792 ("drm/panthor: Add the driver frontend block")
> Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
> ---
> This is spotted by smatch and the patch is only compile tested
> 
> v1->v2: Fix the function panthor_vm_get_heap_pool() to only return error
> pointers and handle the caller sites [Suggested by Boris Brezillon]
> 	- Also merge these IS_ERR() vs NULL bugs into same patch
> ---
>  drivers/gpu/drm/panthor/panthor_drv.c   | 6 +++---
>  drivers/gpu/drm/panthor/panthor_mmu.c   | 2 ++
>  drivers/gpu/drm/panthor/panthor_sched.c | 2 +-
>  3 files changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/panthor/panthor_drv.c
> index 11b3ccd58f85..c8374cd4a30d 100644
> --- a/drivers/gpu/drm/panthor/panthor_drv.c
> +++ b/drivers/gpu/drm/panthor/panthor_drv.c
> @@ -1090,8 +1090,8 @@ static int panthor_ioctl_tiler_heap_destroy(struct drm_device *ddev, void *data,
>  		return -EINVAL;
>  
>  	pool = panthor_vm_get_heap_pool(vm, false);
> -	if (!pool) {
> -		ret = -EINVAL;
> +	if (IS_ERR(pool)) {
> +		ret = PTR_ERR(pool);
>  		goto out_put_vm;
>  	}
>  
> @@ -1385,7 +1385,7 @@ static int panthor_probe(struct platform_device *pdev)
>  
>  	ptdev = devm_drm_dev_alloc(&pdev->dev, &panthor_drm_driver,
>  				   struct panthor_device, base);
> -	if (!ptdev)
> +	if (IS_ERR(ptdev))
>  		return -ENOMEM;
>  

Sorry, that one deserves a separate patch.

>  	platform_set_drvdata(pdev, ptdev);
> diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c b/drivers/gpu/drm/panthor/panthor_mmu.c
> index fdd35249169f..e1285cdb09ff 100644
> --- a/drivers/gpu/drm/panthor/panthor_mmu.c
> +++ b/drivers/gpu/drm/panthor/panthor_mmu.c
> @@ -1893,6 +1893,8 @@ struct panthor_heap_pool *panthor_vm_get_heap_pool(struct panthor_vm *vm, bool c
>  			vm->heaps.pool = panthor_heap_pool_get(pool);
>  	} else {
>  		pool = panthor_heap_pool_get(vm->heaps.pool);
> +		if (!pool)
> +			pool = ERR_PTR(-ENOENT);
>  	}
>  	mutex_unlock(&vm->heaps.lock);
>  
> diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c
> index 5f7803b6fc48..617df2b980d0 100644
> --- a/drivers/gpu/drm/panthor/panthor_sched.c
> +++ b/drivers/gpu/drm/panthor/panthor_sched.c
> @@ -1343,7 +1343,7 @@ static int group_process_tiler_oom(struct panthor_group *group, u32 cs_id)
>  	if (unlikely(csg_id < 0))
>  		return 0;
>  
> -	if (!heaps || frag_end > vt_end || vt_end >= vt_start) {
> +	if (IS_ERR(heaps) || frag_end > vt_end || vt_end >= vt_start) {
>  		ret = -EINVAL;
>  	} else {
>  		/* We do the allocation without holding the scheduler lock to avoid
Harshit Mogalapalli April 2, 2024, 2:05 p.m. UTC | #2
Hi Boris,
On 02/04/24 19:32, Boris Brezillon wrote:
> On Tue,  2 Apr 2024 06:47:08 -0700
> Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> wrote:
> 
>> 1. The devm_drm_dev_alloc() function returns error pointers.
>>     Update the error handling to check for error pointers instead of NULL.
>> 2. Currently panthor_vm_get_heap_pool() returns both ERR_PTR() and
>>     NULL(when create is false and if there is no poool attached to the
>>     VM)
>> 	- Change the function to return error pointers, when pool is
>> 	  NULL return -ENOENT
>> 	- Also handle the callers to check for IS_ERR() on failure.
>>
>> Fixes: 4bdca1150792 ("drm/panthor: Add the driver frontend block")
>> Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
>> ---
>> This is spotted by smatch and the patch is only compile tested
>>
>> v1->v2: Fix the function panthor_vm_get_heap_pool() to only return error
>> pointers and handle the caller sites [Suggested by Boris Brezillon]
>> 	- Also merge these IS_ERR() vs NULL bugs into same patch
>> ---
>>   drivers/gpu/drm/panthor/panthor_drv.c   | 6 +++---
>>   drivers/gpu/drm/panthor/panthor_mmu.c   | 2 ++
>>   drivers/gpu/drm/panthor/panthor_sched.c | 2 +-
>>   3 files changed, 6 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/panthor/panthor_drv.c
>> index 11b3ccd58f85..c8374cd4a30d 100644
>> --- a/drivers/gpu/drm/panthor/panthor_drv.c
>> +++ b/drivers/gpu/drm/panthor/panthor_drv.c
>> @@ -1090,8 +1090,8 @@ static int panthor_ioctl_tiler_heap_destroy(struct drm_device *ddev, void *data,
>>   		return -EINVAL;
>>   
>>   	pool = panthor_vm_get_heap_pool(vm, false);
>> -	if (!pool) {
>> -		ret = -EINVAL;
>> +	if (IS_ERR(pool)) {
>> +		ret = PTR_ERR(pool);
>>   		goto out_put_vm;
>>   	}
>>   
>> @@ -1385,7 +1385,7 @@ static int panthor_probe(struct platform_device *pdev)
>>   
>>   	ptdev = devm_drm_dev_alloc(&pdev->dev, &panthor_drm_driver,
>>   				   struct panthor_device, base);
>> -	if (!ptdev)
>> +	if (IS_ERR(ptdev))
>>   		return -ENOMEM;
>>   
> 
> Sorry, that one deserves a separate patch.
> 

Ah okay, I was confused about the same.
So I will send a V3 removing that part and could you please use the 
independent patch that I sent before ?

https://lore.kernel.org/all/20240402104041.1689951-1-harshit.m.mogalapalli@oracle.com/

Thanks,
Harshit

>>   	platform_set_drvdata(pdev, ptdev);
>> diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c b/drivers/gpu/drm/panthor/panthor_mmu.c
>> index fdd35249169f..e1285cdb09ff 100644
>> --- a/drivers/gpu/drm/panthor/panthor_mmu.c
>> +++ b/drivers/gpu/drm/panthor/panthor_mmu.c
>> @@ -1893,6 +1893,8 @@ struct panthor_heap_pool *panthor_vm_get_heap_pool(struct panthor_vm *vm, bool c
>>   			vm->heaps.pool = panthor_heap_pool_get(pool);
>>   	} else {
>>   		pool = panthor_heap_pool_get(vm->heaps.pool);
>> +		if (!pool)
>> +			pool = ERR_PTR(-ENOENT);
>>   	}
>>   	mutex_unlock(&vm->heaps.lock);
>>   
>> diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c
>> index 5f7803b6fc48..617df2b980d0 100644
>> --- a/drivers/gpu/drm/panthor/panthor_sched.c
>> +++ b/drivers/gpu/drm/panthor/panthor_sched.c
>> @@ -1343,7 +1343,7 @@ static int group_process_tiler_oom(struct panthor_group *group, u32 cs_id)
>>   	if (unlikely(csg_id < 0))
>>   		return 0;
>>   
>> -	if (!heaps || frag_end > vt_end || vt_end >= vt_start) {
>> +	if (IS_ERR(heaps) || frag_end > vt_end || vt_end >= vt_start) {
>>   		ret = -EINVAL;
>>   	} else {
>>   		/* We do the allocation without holding the scheduler lock to avoid
> 
>
Boris Brezillon April 2, 2024, 2:07 p.m. UTC | #3
On Tue, 2 Apr 2024 19:35:41 +0530
Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> wrote:

> Hi Boris,
> On 02/04/24 19:32, Boris Brezillon wrote:
> > On Tue,  2 Apr 2024 06:47:08 -0700
> > Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> wrote:
> >   
> >> 1. The devm_drm_dev_alloc() function returns error pointers.
> >>     Update the error handling to check for error pointers instead of NULL.
> >> 2. Currently panthor_vm_get_heap_pool() returns both ERR_PTR() and
> >>     NULL(when create is false and if there is no poool attached to the
> >>     VM)
> >> 	- Change the function to return error pointers, when pool is
> >> 	  NULL return -ENOENT
> >> 	- Also handle the callers to check for IS_ERR() on failure.
> >>
> >> Fixes: 4bdca1150792 ("drm/panthor: Add the driver frontend block")
> >> Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
> >> ---
> >> This is spotted by smatch and the patch is only compile tested
> >>
> >> v1->v2: Fix the function panthor_vm_get_heap_pool() to only return error
> >> pointers and handle the caller sites [Suggested by Boris Brezillon]
> >> 	- Also merge these IS_ERR() vs NULL bugs into same patch
> >> ---
> >>   drivers/gpu/drm/panthor/panthor_drv.c   | 6 +++---
> >>   drivers/gpu/drm/panthor/panthor_mmu.c   | 2 ++
> >>   drivers/gpu/drm/panthor/panthor_sched.c | 2 +-
> >>   3 files changed, 6 insertions(+), 4 deletions(-)
> >>
> >> diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/panthor/panthor_drv.c
> >> index 11b3ccd58f85..c8374cd4a30d 100644
> >> --- a/drivers/gpu/drm/panthor/panthor_drv.c
> >> +++ b/drivers/gpu/drm/panthor/panthor_drv.c
> >> @@ -1090,8 +1090,8 @@ static int panthor_ioctl_tiler_heap_destroy(struct drm_device *ddev, void *data,
> >>   		return -EINVAL;
> >>   
> >>   	pool = panthor_vm_get_heap_pool(vm, false);
> >> -	if (!pool) {
> >> -		ret = -EINVAL;
> >> +	if (IS_ERR(pool)) {
> >> +		ret = PTR_ERR(pool);
> >>   		goto out_put_vm;
> >>   	}
> >>   
> >> @@ -1385,7 +1385,7 @@ static int panthor_probe(struct platform_device *pdev)
> >>   
> >>   	ptdev = devm_drm_dev_alloc(&pdev->dev, &panthor_drm_driver,
> >>   				   struct panthor_device, base);
> >> -	if (!ptdev)
> >> +	if (IS_ERR(ptdev))
> >>   		return -ENOMEM;
> >>     
> > 
> > Sorry, that one deserves a separate patch.
> >   
> 
> Ah okay, I was confused about the same.
> So I will send a V3 removing that part and could you please use the 
> independent patch that I sent before ?
> 
> https://lore.kernel.org/all/20240402104041.1689951-1-harshit.m.mogalapalli@oracle.com/

Yes, I already added my R-b on that one.
diff mbox series

Patch

diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/panthor/panthor_drv.c
index 11b3ccd58f85..c8374cd4a30d 100644
--- a/drivers/gpu/drm/panthor/panthor_drv.c
+++ b/drivers/gpu/drm/panthor/panthor_drv.c
@@ -1090,8 +1090,8 @@  static int panthor_ioctl_tiler_heap_destroy(struct drm_device *ddev, void *data,
 		return -EINVAL;
 
 	pool = panthor_vm_get_heap_pool(vm, false);
-	if (!pool) {
-		ret = -EINVAL;
+	if (IS_ERR(pool)) {
+		ret = PTR_ERR(pool);
 		goto out_put_vm;
 	}
 
@@ -1385,7 +1385,7 @@  static int panthor_probe(struct platform_device *pdev)
 
 	ptdev = devm_drm_dev_alloc(&pdev->dev, &panthor_drm_driver,
 				   struct panthor_device, base);
-	if (!ptdev)
+	if (IS_ERR(ptdev))
 		return -ENOMEM;
 
 	platform_set_drvdata(pdev, ptdev);
diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c b/drivers/gpu/drm/panthor/panthor_mmu.c
index fdd35249169f..e1285cdb09ff 100644
--- a/drivers/gpu/drm/panthor/panthor_mmu.c
+++ b/drivers/gpu/drm/panthor/panthor_mmu.c
@@ -1893,6 +1893,8 @@  struct panthor_heap_pool *panthor_vm_get_heap_pool(struct panthor_vm *vm, bool c
 			vm->heaps.pool = panthor_heap_pool_get(pool);
 	} else {
 		pool = panthor_heap_pool_get(vm->heaps.pool);
+		if (!pool)
+			pool = ERR_PTR(-ENOENT);
 	}
 	mutex_unlock(&vm->heaps.lock);
 
diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c
index 5f7803b6fc48..617df2b980d0 100644
--- a/drivers/gpu/drm/panthor/panthor_sched.c
+++ b/drivers/gpu/drm/panthor/panthor_sched.c
@@ -1343,7 +1343,7 @@  static int group_process_tiler_oom(struct panthor_group *group, u32 cs_id)
 	if (unlikely(csg_id < 0))
 		return 0;
 
-	if (!heaps || frag_end > vt_end || vt_end >= vt_start) {
+	if (IS_ERR(heaps) || frag_end > vt_end || vt_end >= vt_start) {
 		ret = -EINVAL;
 	} else {
 		/* We do the allocation without holding the scheduler lock to avoid