[PATCH v2] sysctl: Remove unused ctl_table forward declarations

[PATCH v2] sysctl: Remove unused ctl_table forward declarations

[Joel Granados]

Remove superfluous forward declarations of ctl_table from header files
where they are no longer needed. These declarations were left behind
after sysctl code refactoring and cleanup.

Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Muchun Song <muchun.song@linux.dev>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Joel Granados <joel.granados@kernel.org>
---
Apologies for such a big To: list. My idea is for this to go into
mainline through sysctl; get back to me if you prefer otherwise. On the
off chance that this has a V3, let me know if you want to be removed
from the To and I'll make that happen
---
Changes in v2:
- Replaced a ctl_table forward declaration in kernel/printk/internal.h
  with an actual #include <linux/sysctl.h>
- Link to v1: https://lore.kernel.org/r/20251215-jag-sysctl_fw_decl-v1-1-2a9af78448f8@kernel.org
---
 include/linux/fs.h       | 1 -
 include/linux/hugetlb.h  | 2 --
 include/linux/printk.h   | 1 -
 include/net/ax25.h       | 2 --
 kernel/printk/internal.h | 2 +-
 kernel/printk/sysctl.c   | 1 -
 6 files changed, 1 insertion(+), 8 deletions(-)

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 04ceeca12a0d5caadb68643bf68b7a78e17c08d4..77f6302fdced1ef7e61ec1b35bed77c77b294124 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -3487,7 +3487,6 @@ ssize_t simple_attr_write(struct file *file, const char __user *buf,
 ssize_t simple_attr_write_signed(struct file *file, const char __user *buf,
 				 size_t len, loff_t *ppos);
 
-struct ctl_table;
 int __init list_bdev_fs_names(char *buf, size_t size);
 
 #define __FMODE_EXEC		((__force int) FMODE_EXEC)
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 019a1c5281e4e6e04a9207dff7f7aa58c9669a80..18d1c4ecc4f948b179679b8fcc7870f3d466a4d9 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -16,8 +16,6 @@
 #include <linux/userfaultfd_k.h>
 #include <linux/nodemask.h>
 
-struct ctl_table;
-struct user_struct;
 struct mmu_gather;
 struct node;
 
diff --git a/include/linux/printk.h b/include/linux/printk.h
index 45c663124c9bd3b294031d839f1253f410313faa..63d516c873b4c412eead6ee4eb9f90a5c28f630c 100644
--- a/include/linux/printk.h
+++ b/include/linux/printk.h
@@ -78,7 +78,6 @@ extern void console_verbose(void);
 /* strlen("ratelimit") + 1 */
 #define DEVKMSG_STR_MAX_SIZE 10
 extern char devkmsg_log_str[DEVKMSG_STR_MAX_SIZE];
-struct ctl_table;
 
 extern int suppress_printk;
 
diff --git a/include/net/ax25.h b/include/net/ax25.h
index a7bba42dde153a2aeaf010a7ef8b48d39d15a835..beec9712e9c71d4be90acb6fc7113022527bc1ab 100644
--- a/include/net/ax25.h
+++ b/include/net/ax25.h
@@ -215,8 +215,6 @@ typedef struct {
 	unsigned short		slave_timeout;		/* when? */
 } ax25_dama_info;
 
-struct ctl_table;
-
 typedef struct ax25_dev {
 	struct list_head	list;
 
diff --git a/kernel/printk/internal.h b/kernel/printk/internal.h
index 5f5f626f427942ed8ea310f08c285775d8e095a6..29a3bd1799d426bc7b5ebdc28ff8b75214c57a57 100644
--- a/kernel/printk/internal.h
+++ b/kernel/printk/internal.h
@@ -4,9 +4,9 @@
  */
 #include <linux/console.h>
 #include <linux/types.h>
+#include <linux/sysctl.h>
 
 #if defined(CONFIG_PRINTK) && defined(CONFIG_SYSCTL)
-struct ctl_table;
 void __init printk_sysctl_init(void);
 int devkmsg_sysctl_set_loglvl(const struct ctl_table *table, int write,
 			      void *buffer, size_t *lenp, loff_t *ppos);
diff --git a/kernel/printk/sysctl.c b/kernel/printk/sysctl.c
index da77f3f5c1fe917d9ce2d777355403f123587757..f15732e93c2e9c0865c42e4af9cb6458d4402c0a 100644
--- a/kernel/printk/sysctl.c
+++ b/kernel/printk/sysctl.c
@@ -3,7 +3,6 @@
  * sysctl.c: General linux system control interface
  */
 
-#include <linux/sysctl.h>
 #include <linux/printk.h>
 #include <linux/capability.h>
 #include <linux/ratelimit.h>

---
base-commit: 8f0b4cce4481fb22653697cced8d0d04027cb1e8
change-id: 20251215-jag-sysctl_fw_decl-58c718715c8c

Best regards,
-- 
Joel Granados <joel.granados@kernel.org>

Re: [PATCH v2] sysctl: Remove unused ctl_table forward declarations

[Paolo Abeni]

On 12/17/25 1:16 PM, Joel Granados wrote:
> Remove superfluous forward declarations of ctl_table from header files
> where they are no longer needed. These declarations were left behind
> after sysctl code refactoring and cleanup.
> 
> Reviewed-by: Jan Kara <jack@suse.cz>
> Acked-by: Muchun Song <muchun.song@linux.dev>
> Reviewed-by: Petr Mladek <pmladek@suse.com>
> Signed-off-by: Joel Granados <joel.granados@kernel.org>
> ---
> Apologies for such a big To: list. My idea is for this to go into
> mainline through sysctl; get back to me if you prefer otherwise. On the
> off chance that this has a V3, let me know if you want to be removed
> from the To and I'll make that happen

For the net bits:

Acked-by: Paolo Abeni <pabeni@redhat.com>

I'm ok with merging this via the sysctl tree, given that we don't see
much action happening in the ax25 header (and very low chances of
conflicts). But I would be also ok if you would split this into multiple
patches, one for each affected subsystem.

/P

Re: [PATCH v2] sysctl: Remove unused ctl_table forward declarations

[Joel Granados]

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On Fri, Dec 19, 2025 at 10:28:31AM +0100, Paolo Abeni wrote:
> On 12/17/25 1:16 PM, Joel Granados wrote:
> > Remove superfluous forward declarations of ctl_table from header files
> > where they are no longer needed. These declarations were left behind
> > after sysctl code refactoring and cleanup.
> > 
> > Reviewed-by: Jan Kara <jack@suse.cz>
> > Acked-by: Muchun Song <muchun.song@linux.dev>
> > Reviewed-by: Petr Mladek <pmladek@suse.com>
> > Signed-off-by: Joel Granados <joel.granados@kernel.org>
> > ---
> > Apologies for such a big To: list. My idea is for this to go into
> > mainline through sysctl; get back to me if you prefer otherwise. On the
> > off chance that this has a V3, let me know if you want to be removed
> > from the To and I'll make that happen
> 
> For the net bits:
> 
> Acked-by: Paolo Abeni <pabeni@redhat.com>
> 
> I'm ok with merging this via the sysctl tree, given that we don't see
> much action happening in the ax25 header (and very low chances of
> conflicts). But I would be also ok if you would split this into multiple
> patches, one for each affected subsystem.
I'll separate it, if I send a V3

Thx for the feedback.

-- 

Joel Granados

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