Re: [PATCH] xen-blkback: clear PF_NOFREEZE for xen_blkif_schedule()

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Mon, Oct 26, 2015 at 02:47:21PM +0900, Jiri Kosina wrote:
> From: Jiri Kosina <jkosina@suse.cz>
> 
> xen_blkif_schedule() kthread calls try_to_freeze() at the beginning of 
> every attempt to purge the LRU. This operation can't ever succeed though, 
> as the kthread hasn't marked itself as freezable.

<nods>!
> 
> Before (hopefully eventually) kthread freezing gets converted to fileystem 
> freezing, we'd rather mark xen_blkif_schedule() freezable (as it can 
> generate I/O during suspend).
> 
> Signed-off-by: Jiri Kosina <jkosina@suse.cz>

Thank you for reporting that. Will queue it up for Linux 4.5!
> ---
>  drivers/block/xen-blkback/blkback.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c
> index af3caa3..bb65f7c 100644
> --- a/drivers/block/xen-blkback/blkback.c
> +++ b/drivers/block/xen-blkback/blkback.c
> @@ -597,6 +597,7 @@ int xen_blkif_schedule(void *arg)
>  
>  	xen_blkif_get(blkif);
>  
> +	set_freezable();
>  	while (!kthread_should_stop()) {
>  		if (unlikely(vbd->size != vbd_sz(vbd)))
>  			xen_vbd_resize(blkif);
> 
> -- 
> Jiri Kosina
> SUSE Labs