[PATCH] cdx: Fix cdx_mmap_resource() after constifying attr in ->mmap()

[PATCH] cdx: Fix cdx_mmap_resource() after constifying attr in ->mmap()

[Nathan Chancellor]

Commit 94a20fb9af16 ("sysfs: treewide: constify attribute callback of
bin_attribute::mmap()") missed updating the attr parameter of
cdx_mmap_resource(), resulting in a build failure.

  drivers/cdx/cdx.c: In function 'cdx_create_res_attr':
  drivers/cdx/cdx.c:773:24: error: assignment to 'int (*)(struct file *, struct kobject *, const struct bin_attribute *, struct vm_area_struct *)' from incompatible pointer type 'int (*)(struct file *, struct kobject *, struct bin_attribute *, struct vm_area_struct *)' [-Wincompatible-pointer-types]
    773 |         res_attr->mmap = cdx_mmap_resource;
        |                        ^

Update cdx_mmap_resource() to match, resolving the build failure.

Fixes: 94a20fb9af16 ("sysfs: treewide: constify attribute callback of bin_attribute::mmap()")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
---
 drivers/cdx/cdx.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/cdx/cdx.c b/drivers/cdx/cdx.c
index 07371cb653d356977cbd3dd99a1b848146d5a993..316bd89a95caf97163a126478985c52b1b596bb4 100644
--- a/drivers/cdx/cdx.c
+++ b/drivers/cdx/cdx.c
@@ -707,7 +707,7 @@ static const struct vm_operations_struct cdx_phys_vm_ops = {
  * Return: true on success, false otherwise.
  */
 static int cdx_mmap_resource(struct file *fp, struct kobject *kobj,
-			     struct bin_attribute *attr,
+			     const struct bin_attribute *attr,
 			     struct vm_area_struct *vma)
 {
 	struct cdx_device *cdx_dev = to_cdx_device(kobj_to_dev(kobj));

---
base-commit: 298c2af4788ed027a42c2bab0f210219825fb5fd
change-id: 20241107-sysfs-const-mmap-fix-cdx-1457914fe16d

Best regards,
-- 
Nathan Chancellor <nathan@kernel.org>

Re: [PATCH] cdx: Fix cdx_mmap_resource() after constifying attr in ->mmap()

[Thorsten Leemhuis]

On 07.11.24 18:07, Nathan Chancellor wrote:
> Commit 94a20fb9af16 ("sysfs: treewide: constify attribute callback of
> bin_attribute::mmap()") missed updating the attr parameter of
> cdx_mmap_resource(), resulting in a build failure.
> 
>   drivers/cdx/cdx.c: In function 'cdx_create_res_attr':
>   drivers/cdx/cdx.c:773:24: error: assignment to 'int (*)(struct file *, struct kobject *, const struct bin_attribute *, struct vm_area_struct *)' from incompatible pointer type 'int (*)(struct file *, struct kobject *, struct bin_attribute *, struct vm_area_struct *)' [-Wincompatible-pointer-types]
>     773 |         res_attr->mmap = cdx_mmap_resource;
>         |                        ^
> 
> Update cdx_mmap_resource() to match, resolving the build failure.
> 
> Fixes: 94a20fb9af16 ("sysfs: treewide: constify attribute callback of bin_attribute::mmap()")
> Signed-off-by: Nathan Chancellor <nathan@kernel.org>

Ran into the described problem for my daily -next builds on all Fedora
releases on ARM64 yesterday and today. This fixes it for me.

Tested-by: Thorsten Leemhuis <linux@leemhuis.info>

Ciao, Thorsten

Re: [PATCH] cdx: Fix cdx_mmap_resource() after constifying attr in ->mmap()

[Thomas Weißschuh]

Hi Nathan,

Nov 7, 2024 12:07:56 Nathan Chancellor <nathan@kernel.org>:

> Commit 94a20fb9af16 ("sysfs: treewide: constify attribute callback of
> bin_attribute::mmap()") missed updating the attr parameter of
> cdx_mmap_resource(), resulting in a build failure.
>
>   drivers/cdx/cdx.c: In function 'cdx_create_res_attr':
>   drivers/cdx/cdx.c:773:24: error: assignment to 'int (*)(struct file *, struct kobject *, const struct bin_attribute *, struct vm_area_struct *)' from incompatible pointer type 'int (*)(struct file *, struct kobject *, struct bin_attribute *, struct vm_area_struct *)' [-Wincompatible-pointer-types]
>     773 |         res_attr->mmap = cdx_mmap_resource;
>         |                        ^
>
> Update cdx_mmap_resource() to match, resolving the build failure.
>
> Fixes: 94a20fb9af16 ("sysfs: treewide: constify attribute callback of bin_attribute::mmap()")

I'm not sure about the Fixes tag.
cdx.c is not yet in mainline and this change should be folded into the cdx patch or the sysfs patch, depending on their order in the merge window.
I guess Greg will take care of it.

Thanks for the notification, though!

> Signed-off-by: Nathan Chancellor <nathan@kernel.org>

If it ends up as a real commit:

Reviewed-by: Thomas Weißschuu <linux@weissschuh.net>

> ---
> drivers/cdx/cdx.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/cdx/cdx.c b/drivers/cdx/cdx.c
> index 07371cb653d356977cbd3dd99a1b848146d5a993..316bd89a95caf97163a126478985c52b1b596bb4 100644
> --- a/drivers/cdx/cdx.c
> +++ b/drivers/cdx/cdx.c
> @@ -707,7 +707,7 @@ static const struct vm_operations_struct cdx_phys_vm_ops = {
>   * Return: true on success, false otherwise.
>   */
> static int cdx_mmap_resource(struct file *fp, struct kobject *kobj,
> -                struct bin_attribute *attr,
> +                const struct bin_attribute *attr,
>                  struct vm_area_struct *vma)
> {
>     struct cdx_device *cdx_dev = to_cdx_device(kobj_to_dev(kobj));
>
> ---
> base-commit: 298c2af4788ed027a42c2bab0f210219825fb5fd
> change-id: 20241107-sysfs-const-mmap-fix-cdx-1457914fe16d
>
> Best regards,
> --
> Nathan Chancellor <nathan@kernel.org>

Re: [PATCH] cdx: Fix cdx_mmap_resource() after constifying attr in ->mmap()

[Nathan Chancellor]

On Fri, Nov 08, 2024 at 12:23:50PM -0500, Thomas Weißschuh wrote:
> Nov 7, 2024 12:07:56 Nathan Chancellor <nathan@kernel.org>:
> > Fixes: 94a20fb9af16 ("sysfs: treewide: constify attribute callback of bin_attribute::mmap()")
> 
> I'm not sure about the Fixes tag.
> cdx.c is not yet in mainline and this change should be folded into the cdx patch or the sysfs patch, depending on their order in the merge window.
> I guess Greg will take care of it.

This code is in mainline, so I think the Fixes tag is correct?

  $ git grep cdx_mmap_resource v6.12-rc1 drivers/cdx/cdx.c
  v6.12-rc1:drivers/cdx/cdx.c: * cdx_mmap_resource - map a CDX resource into user memory space
  v6.12-rc1:drivers/cdx/cdx.c:static int cdx_mmap_resource(struct file *fp, struct kobject *kobj,
  v6.12-rc1:drivers/cdx/cdx.c:        res_attr->mmap = cdx_mmap_resource;

The error is reproducible on driver-core-next since that is what I based
this change on.

Thanks for the review!

Cheers,
Nathan

Re: [PATCH] cdx: Fix cdx_mmap_resource() after constifying attr in ->mmap()

[Thomas Weißschuh]

Nov 8, 2024 12:54:41 Nathan Chancellor <nathan@kernel.org>:

> On Fri, Nov 08, 2024 at 12:23:50PM -0500, Thomas Weißschuh wrote:
>> Nov 7, 2024 12:07:56 Nathan Chancellor <nathan@kernel.org>:
>>> Fixes: 94a20fb9af16 ("sysfs: treewide: constify attribute callback of bin_attribute::mmap()")
>>
>> I'm not sure about the Fixes tag.
>> cdx.c is not yet in mainline and this change should be folded into the cdx patch or the sysfs patch, depending on their order in the merge window.
>> I guess Greg will take care of it.
>
> This code is in mainline, so I think the Fixes tag is correct?

Indeed. Sorry for the noise.
I re-checked this before writing the other mail, but somehow failed.
(Maybe because I did it on a phone)

I'm wondering how this got through 0day, too.
Anyways, it shouldn't matter.
Thanks again for the fix!

>   $ git grep cdx_mmap_resource v6.12-rc1 drivers/cdx/cdx.c
>   v6.12-rc1:drivers/cdx/cdx.c: * cdx_mmap_resource - map a CDX resource into user memory space
>   v6.12-rc1:drivers/cdx/cdx.c:static int cdx_mmap_resource(struct file *fp, struct kobject *kobj,
>   v6.12-rc1:drivers/cdx/cdx.c:        res_attr->mmap = cdx_mmap_resource;
>
> The error is reproducible on driver-core-next since that is what I based
> this change on.
>
> Thanks for the review!
>
> Cheers,
> Nathan

RE: [PATCH] cdx: Fix cdx_mmap_resource() after constifying attr in ->mmap()

[Agarwal, Nikhil]

> 
> Commit 94a20fb9af16 ("sysfs: treewide: constify attribute callback of
> bin_attribute::mmap()") missed updating the attr parameter of
> cdx_mmap_resource(), resulting in a build failure.
> 
>   drivers/cdx/cdx.c: In function 'cdx_create_res_attr':
>   drivers/cdx/cdx.c:773:24: error: assignment to 'int (*)(struct file *, struct kobject *,
> const struct bin_attribute *, struct vm_area_struct *)' from incompatible pointer type
> 'int (*)(struct file *, struct kobject *, struct bin_attribute *, struct vm_area_struct *)' [-
> Wincompatible-pointer-types]
>     773 |         res_attr->mmap = cdx_mmap_resource;
>         |                        ^
> 
> Update cdx_mmap_resource() to match, resolving the build failure.
> 
> Fixes: 94a20fb9af16 ("sysfs: treewide: constify attribute callback of
> bin_attribute::mmap()")
> Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Nikhil Agarwal <nikhil.agarwal@amd.com>