Re: [PATCH 17/17] sysctl: assert static storage for DEFINE_CTL_TABLE_POLL()

Joel Granados <[email protected]> Fri, 18 Sep 2026 09:21:18 +0200

Newsgroups	org.kernel.vger.linux-fsdevel,dev.linux.lists.linux-rt-devel,dev.linux.lists.llvm,dev.linux.lists.virtualization,org.kernel.vger.linux-kernel,org.kernel.vger.netdev,org.kernel.vger.rcu,org.kvack.linux-mm,org.ozlabs.lists.linuxppc-dev
Message-ID	<av3s3fgets23siaqxbtyu5gvcekqpq2nmyey6oa6o6amfj6jbi@zomsnfvvxtf4>

On Mon, Sep 14, 2026 at 11:13:32PM -0400, Yury Norov wrote:
> DEFINE_CTL_TABLE_POLL() statically initializes an embedded wait queue.
> An automatic local poll object cannot provide the persistent lockdep
> class key expected by its wait queue lock.
> 
> Add ASSERT_STATIC_STORAGE() to reject automatic declarations while
> preserving file-scope and static local definitions. Leave the underlying
> initializer available for embedded objects.
> 
> Assisted-by: OpenAI Codex
> Signed-off-by: Yury Norov <[email protected]>
> ---
>  include/linux/sysctl.h | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
> index e5d7226ab6f5..be79359346af 100644
> --- a/include/linux/sysctl.h
> +++ b/include/linux/sysctl.h
> @@ -22,6 +22,7 @@
>  #ifndef _LINUX_SYSCTL_H
>  #define _LINUX_SYSCTL_H
>  
> +#include <linux/compiler.h>
>  #include <linux/list.h>
>  #include <linux/rcupdate.h>
>  #include <linux/wait.h>
> @@ -216,7 +217,8 @@ static inline void *proc_sys_poll_event(struct ctl_table_poll *poll)
>  	.wait = __WAIT_QUEUE_HEAD_INITIALIZER(name.wait) }
>  
>  #define DEFINE_CTL_TABLE_POLL(name)					\
> -	struct ctl_table_poll name = __CTL_TABLE_POLL_INITIALIZER(name)
> +	struct ctl_table_poll name = __CTL_TABLE_POLL_INITIALIZER(name);	\
> +	ASSERT_STATIC_STORAGE(name)
>  
>  /* A sysctl table is an array of struct ctl_table: */
>  struct ctl_table {
> -- 
> 2.53.0
> 

This looks OK for sysctl and the two users of DEFINE_CTL_TABLE_POLL in
utsname_sysctl.c (hostname_poll and domainname_poll)

Reviewed-by: Joel Granados <[email protected]>

Best

signature.asc (application/pgp-signature, 659 B)