Re: [PATCH] s390/pkey: Remove synchronize_rcu from pkey_handler_register

[Harald Freudenberger <freude@linux.ibm.com>]

On 2026-03-13 06:23, lirongqing wrote:
> From: Li RongQing <lirongqing@baidu.com>
> 
> The synchronize_rcu() call after adding a handler to the handler_list
> is redundant because RCU readers will either see the old list or the
> new list. Removing this synchronization point reduces the blocking
> time during handler registration.
> 
> Signed-off-by: Li RongQing <lirongqing@baidu.com>
> ---
>  drivers/s390/crypto/pkey_base.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/drivers/s390/crypto/pkey_base.c 
> b/drivers/s390/crypto/pkey_base.c
> index d60cd98..c2e29d6 100644
> --- a/drivers/s390/crypto/pkey_base.c
> +++ b/drivers/s390/crypto/pkey_base.c
> @@ -60,7 +60,6 @@ int pkey_handler_register(struct pkey_handler 
> *handler)
> 
>  	list_add_rcu(&handler->list, &handler_list);
>  	spin_unlock(&handler_list_write_lock);
> -	synchronize_rcu();
> 
>  	module_put(handler->module);

Thanks Li RongQing

Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>

@Heiko/@Vasily/@Alexander will you pick this?