Re: [PATCH v1 01/11] relay: zero page->private when freeing pages

[Usama Arif]

On Sun, 22 Feb 2026 22:26:31 -0500 Zi Yan <ziy@xxxxxxxxxx> wrote:

> This prepares for upcoming page->private checks in page freeing path.
> 
> Signed-off-by: Zi Yan <ziy@xxxxxxxxxx>
> Cc: Jason Xing <kernelxing@xxxxxxxxxxx>
> Cc: Yushan Zhou <katrinzhou@xxxxxxxxxxx>
> Cc: "Masami Hiramatsu (Google)" <mhiramat@xxxxxxxxxx>
> ---
>  kernel/relay.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/kernel/relay.c b/kernel/relay.c
> index 5c665b729132..d16f9966817f 100644
> --- a/kernel/relay.c
> +++ b/kernel/relay.c
> @@ -131,8 +131,10 @@ static void *relay_alloc_buf(struct rchan_buf *buf, size_t *size)
>  	return mem;
>  
>  depopulate:
> -	for (j = 0; j < i; j++)
> +	for (j = 0; j < i; j++) {
> +		set_page_private(buf->page_array[i], 0);

Hi Zi,

Should the index into page_array be j and not i over here?

>  		__free_page(buf->page_array[j]);
> +	}
>  	relay_free_page_array(buf->page_array);
>  	return NULL;
>  }
> @@ -196,8 +198,10 @@ static void relay_destroy_buf(struct rchan_buf *buf)
>  
>  	if (likely(buf->start)) {
>  		vunmap(buf->start);
> -		for (i = 0; i < buf->page_count; i++)
> +		for (i = 0; i < buf->page_count; i++) {
> +			set_page_private(buf->page_array[i], 0);
>  			__free_page(buf->page_array[i]);
> +		}
>  		relay_free_page_array(buf->page_array);
>  	}
>  	*per_cpu_ptr(chan->buf, buf->cpu) = NULL;
> -- 
> 2.51.0
> 
>