Replace simple_strtoul() with the recommended kstrtoul() for parsing the
'dhash_entries=' boot parameter.

Check the return value of kstrtoul() and reject invalid values. This
adds error handling while preserving behavior for existing values, and
removes use of the deprecated simple_strtoul() helper.

Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
---
 fs/dcache.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/fs/dcache.c b/fs/dcache.c
index dc2fff4811d1..ec275f4fd81c 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -3227,10 +3227,7 @@ EXPORT_SYMBOL(d_parent_ino);
 static __initdata unsigned long dhash_entries;
 static int __init set_dhash_entries(char *str)
 {
-	if (!str)
-		return 0;
-	dhash_entries = simple_strtoul(str, &str, 0);
-	return 1;
+	return kstrtoul(str, 0, &dhash_entries) == 0;
 }
 __setup("dhash_entries=", set_dhash_entries);
 
-- 
Thorsten Blum <thorsten.blum@linux.dev>
GPG: 1D60 735E 8AEF 3BE4 73B6  9D84 7336 78FD 8DFE EAD4

On Tue, 16 Dec 2025 15:52:37 +0100, Thorsten Blum wrote:
> Replace simple_strtoul() with the recommended kstrtoul() for parsing the
> 'dhash_entries=' boot parameter.
> 
> Check the return value of kstrtoul() and reject invalid values. This
> adds error handling while preserving behavior for existing values, and
> removes use of the deprecated simple_strtoul() helper.
> 
> [...]

Applied to the vfs-7.0.misc branch of the vfs/vfs.git tree.
Patches in the vfs-7.0.misc branch should appear in linux-next soon.

Please report any outstanding bugs that were missed during review in a
new review to the original patch series allowing us to drop it.

It's encouraged to provide Acked-bys and Reviewed-bys even though the
patch has now been applied. If possible patch trailers will be updated.

Note that commit hashes shown below are subject to change due to rebase,
trailer updates or similar. If in doubt, please check the listed branch.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
branch: vfs-7.0.misc

[1/1] dcache: Replace simple_strtoul with kstrtoul in set_dhash_entries
      https://git.kernel.org/vfs/vfs/c/b29a0a37f46b

On Tue 16-12-25 15:52:37, Thorsten Blum wrote:
> Replace simple_strtoul() with the recommended kstrtoul() for parsing the
> 'dhash_entries=' boot parameter.
> 
> Check the return value of kstrtoul() and reject invalid values. This
> adds error handling while preserving behavior for existing values, and
> removes use of the deprecated simple_strtoul() helper.
> 
> Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@suse.cz>

								Honza

> ---
>  fs/dcache.c | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
> 
> diff --git a/fs/dcache.c b/fs/dcache.c
> index dc2fff4811d1..ec275f4fd81c 100644
> --- a/fs/dcache.c
> +++ b/fs/dcache.c
> @@ -3227,10 +3227,7 @@ EXPORT_SYMBOL(d_parent_ino);
>  static __initdata unsigned long dhash_entries;
>  static int __init set_dhash_entries(char *str)
>  {
> -	if (!str)
> -		return 0;
> -	dhash_entries = simple_strtoul(str, &str, 0);
> -	return 1;
> +	return kstrtoul(str, 0, &dhash_entries) == 0;
>  }
>  __setup("dhash_entries=", set_dhash_entries);
>  
> -- 
> Thorsten Blum <thorsten.blum@linux.dev>
> GPG: 1D60 735E 8AEF 3BE4 73B6  9D84 7336 78FD 8DFE EAD4
> 
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR