Re: [PATCH] powerpc: fix debugfs_create_dir error checking
On Sun, 28 May 2023 13:16:44 +0530, mirim...@outlook.com wrote: > The debugfs_create_dir returns ERR_PTR incase of an error and the > correct way of checking it by using the IS_ERR inline function, and > not the simple null comparision. This patch fixes this. > > Applied to powerpc/next. [1/1] powerpc: fix debugfs_create_dir error checking https://git.kernel.org/powerpc/c/429356fac0440b962aaa6d3688709813a21dd122 cheers
Re: [PATCH] powerpc: fix debugfs_create_dir error checking
> Still I think this patch is an improvement so I'll plan to merge it.
Please let me know when you commit it.
Thanks
Immad.
On Tue, May 30, 2023 at 4:17 PM Michael Ellerman wrote:
> Greg KH writes:
> > On Sun, May 28, 2023 at 01:16:44PM +0530, mirim...@outlook.com wrote:
> >> From: Immad Mir
> >>
> >> The debugfs_create_dir returns ERR_PTR incase of an error and the
> >> correct way of checking it by using the IS_ERR inline function, and
> >> not the simple null comparision. This patch fixes this.
> >>
> >> Suggested-By: Ivan Orlov
> >> Signed-off-by: Immad Mir
> >> ---
> >> arch/powerpc/platforms/powernv/opal-xscom.c | 4 ++--
> >> 1 file changed, 2 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/arch/powerpc/platforms/powernv/opal-xscom.c
> b/arch/powerpc/platforms/powernv/opal-xscom.c
> >> index 6b4eed2ef..262cd6fac 100644
> >> --- a/arch/powerpc/platforms/powernv/opal-xscom.c
> >> +++ b/arch/powerpc/platforms/powernv/opal-xscom.c
> >> @@ -168,7 +168,7 @@ static int scom_debug_init_one(struct dentry *root,
> struct device_node *dn,
> >> ent->path.size = strlen((char *)ent->path.data);
> >>
> >> dir = debugfs_create_dir(ent->name, root);
> >> -if (!dir) {
> >> +if (IS_ERR(dir)) {
> >> kfree(ent->path.data);
> >> kfree(ent);
> >> return -1;
> >
> > Why is this driver caring if debugfs is working or not at all? It
> > should just ignore the error and keep moving forward.
>
> It's creating directories and then creating files in those directories.
> So I think it makes sense that it checks that the directory was created
> successfully. It doesn't check whether the files were created.
>
> > And -1 is not a valid error number :(
>
> It's EPERM :) - but yeah probably not really the right error in this
> case.
>
> Still I think this patch is an improvement so I'll plan to merge it.
>
> cheers
>
Re: [PATCH] powerpc: fix debugfs_create_dir error checking
Greg KH writes:
> On Sun, May 28, 2023 at 01:16:44PM +0530, mirim...@outlook.com wrote:
>> From: Immad Mir
>>
>> The debugfs_create_dir returns ERR_PTR incase of an error and the
>> correct way of checking it by using the IS_ERR inline function, and
>> not the simple null comparision. This patch fixes this.
>>
>> Suggested-By: Ivan Orlov
>> Signed-off-by: Immad Mir
>> ---
>> arch/powerpc/platforms/powernv/opal-xscom.c | 4 ++--
>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/powerpc/platforms/powernv/opal-xscom.c
>> b/arch/powerpc/platforms/powernv/opal-xscom.c
>> index 6b4eed2ef..262cd6fac 100644
>> --- a/arch/powerpc/platforms/powernv/opal-xscom.c
>> +++ b/arch/powerpc/platforms/powernv/opal-xscom.c
>> @@ -168,7 +168,7 @@ static int scom_debug_init_one(struct dentry *root,
>> struct device_node *dn,
>> ent->path.size = strlen((char *)ent->path.data);
>>
>> dir = debugfs_create_dir(ent->name, root);
>> -if (!dir) {
>> +if (IS_ERR(dir)) {
>> kfree(ent->path.data);
>> kfree(ent);
>> return -1;
>
> Why is this driver caring if debugfs is working or not at all? It
> should just ignore the error and keep moving forward.
It's creating directories and then creating files in those directories.
So I think it makes sense that it checks that the directory was created
successfully. It doesn't check whether the files were created.
> And -1 is not a valid error number :(
It's EPERM :) - but yeah probably not really the right error in this
case.
Still I think this patch is an improvement so I'll plan to merge it.
cheers
Re: [PATCH] powerpc: fix debugfs_create_dir error checking
> Why is this driver caring if debugfs is working or not at all? It
> should just ignore the error and keep moving forward.
I do not know. But, if the authors of the driver have decided to check for
the error, maybe use the more appropriate way?
Thanks.
Immad.
On Sun, May 28, 2023 at 1:27 PM Greg KH wrote:
> On Sun, May 28, 2023 at 01:16:44PM +0530, mirim...@outlook.com wrote:
> > From: Immad Mir
> >
> > The debugfs_create_dir returns ERR_PTR incase of an error and the
> > correct way of checking it by using the IS_ERR inline function, and
> > not the simple null comparision. This patch fixes this.
> >
> > Suggested-By: Ivan Orlov
> > Signed-off-by: Immad Mir
> > ---
> > arch/powerpc/platforms/powernv/opal-xscom.c | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/powerpc/platforms/powernv/opal-xscom.c
> b/arch/powerpc/platforms/powernv/opal-xscom.c
> > index 6b4eed2ef..262cd6fac 100644
> > --- a/arch/powerpc/platforms/powernv/opal-xscom.c
> > +++ b/arch/powerpc/platforms/powernv/opal-xscom.c
> > @@ -168,7 +168,7 @@ static int scom_debug_init_one(struct dentry *root,
> struct device_node *dn,
> > ent->path.size = strlen((char *)ent->path.data);
> >
> > dir = debugfs_create_dir(ent->name, root);
> > - if (!dir) {
> > + if (IS_ERR(dir)) {
> > kfree(ent->path.data);
> > kfree(ent);
> > return -1;
>
> Why is this driver caring if debugfs is working or not at all? It
> should just ignore the error and keep moving forward.
>
> And -1 is not a valid error number :(
>
> Have you hit this error on this driver?
>
> thanks,
>
> greg k-h
>
Re: [PATCH] powerpc: fix debugfs_create_dir error checking
On Sun, May 28, 2023 at 01:16:44PM +0530, mirim...@outlook.com wrote:
> From: Immad Mir
>
> The debugfs_create_dir returns ERR_PTR incase of an error and the
> correct way of checking it by using the IS_ERR inline function, and
> not the simple null comparision. This patch fixes this.
>
> Suggested-By: Ivan Orlov
> Signed-off-by: Immad Mir
> ---
> arch/powerpc/platforms/powernv/opal-xscom.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/powerpc/platforms/powernv/opal-xscom.c
> b/arch/powerpc/platforms/powernv/opal-xscom.c
> index 6b4eed2ef..262cd6fac 100644
> --- a/arch/powerpc/platforms/powernv/opal-xscom.c
> +++ b/arch/powerpc/platforms/powernv/opal-xscom.c
> @@ -168,7 +168,7 @@ static int scom_debug_init_one(struct dentry *root,
> struct device_node *dn,
> ent->path.size = strlen((char *)ent->path.data);
>
> dir = debugfs_create_dir(ent->name, root);
> - if (!dir) {
> + if (IS_ERR(dir)) {
> kfree(ent->path.data);
> kfree(ent);
> return -1;
Why is this driver caring if debugfs is working or not at all? It
should just ignore the error and keep moving forward.
And -1 is not a valid error number :(
Have you hit this error on this driver?
thanks,
greg k-h
[PATCH] powerpc: fix debugfs_create_dir error checking
From: Immad Mir
The debugfs_create_dir returns ERR_PTR incase of an error and the
correct way of checking it by using the IS_ERR inline function, and
not the simple null comparision. This patch fixes this.
Suggested-By: Ivan Orlov
Signed-off-by: Immad Mir
---
arch/powerpc/platforms/powernv/opal-xscom.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/platforms/powernv/opal-xscom.c
b/arch/powerpc/platforms/powernv/opal-xscom.c
index 6b4eed2ef..262cd6fac 100644
--- a/arch/powerpc/platforms/powernv/opal-xscom.c
+++ b/arch/powerpc/platforms/powernv/opal-xscom.c
@@ -168,7 +168,7 @@ static int scom_debug_init_one(struct dentry *root, struct
device_node *dn,
ent->path.size = strlen((char *)ent->path.data);
dir = debugfs_create_dir(ent->name, root);
- if (!dir) {
+ if (IS_ERR(dir)) {
kfree(ent->path.data);
kfree(ent);
return -1;
@@ -190,7 +190,7 @@ static int scom_debug_init(void)
return 0;
root = debugfs_create_dir("scom", arch_debugfs_dir);
- if (!root)
+ if (IS_ERR(root))
return -1;
rc = 0;
--
2.40.0
[PATCH] powerpc: fix debugfs_create_dir error checking
From: Immad Mir
The debugfs_create_dir returns ERR_PTR incase of an error and the
correct way of checking it by using the IS_ERR inline function, and
not the simple null comparision. This patch fixes this.
Suggested-By: Ivan Orlov
Signed-off-by: Immad Mir
---
arch/powerpc/platforms/powernv/opal-xscom.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/platforms/powernv/opal-xscom.c
b/arch/powerpc/platforms/powernv/opal-xscom.c
index 6b4eed2ef..262cd6fac 100644
--- a/arch/powerpc/platforms/powernv/opal-xscom.c
+++ b/arch/powerpc/platforms/powernv/opal-xscom.c
@@ -168,7 +168,7 @@ static int scom_debug_init_one(struct dentry *root, struct
device_node *dn,
ent->path.size = strlen((char *)ent->path.data);
dir = debugfs_create_dir(ent->name, root);
- if (!dir) {
+ if (IS_ERR(dir)) {
kfree(ent->path.data);
kfree(ent);
return -1;
@@ -190,7 +190,7 @@ static int scom_debug_init(void)
return 0;
root = debugfs_create_dir("scom", arch_debugfs_dir);
- if (!root)
+ if (IS_ERR(root))
return -1;
rc = 0;
--
2.40.0
