Re: [PATCH] md: Fix unexpected behaviour in is_mddev_idle

[Luis Chamberlain]

On Wed, Dec 01, 2021 at 11:27:12AM +0800, Li Jinlin wrote:
> diff --git a/drivers/md/md.c b/drivers/md/md.c
> index 5111ed966947..f47035838c43 100644
> --- a/drivers/md/md.c
> +++ b/drivers/md/md.c
> @@ -8429,14 +8429,14 @@ static int is_mddev_idle(struct mddev *mddev, int init)
>  {
>  	struct md_rdev *rdev;
>  	int idle;
> -	int curr_events;
> +	long curr_events;

>  
>  	idle = 1;
>  	rcu_read_lock();
>  	rdev_for_each_rcu(rdev, mddev) {
>  		struct gendisk *disk = rdev->bdev->bd_disk;
> -		curr_events = (int)part_stat_read_accum(disk->part0, sectors) -
> -			      atomic_read(&disk->sync_io);
> +		curr_events = (long)part_stat_read_accum(disk->part0, sectors) -
> +			      atomic64_read(&disk->sync_io);

And what makes you believe you might not have to go and change all other
drivers to address this as well?

>  static inline void md_sync_acct_bio(struct bio *bio, unsigned long nr_sectors)
> diff --git a/include/linux/genhd.h b/include/linux/genhd.h
> index 74c410263113..efa7884de11b 100644
> --- a/include/linux/genhd.h
> +++ b/include/linux/genhd.h
> @@ -150,7 +150,7 @@ struct gendisk {
>  	struct list_head slave_bdevs;
>  #endif
>  	struct timer_rand_state *random;
> -	atomic_t sync_io;		/* RAID */
> +	atomic64_t sync_io;		/* RAID */
>  	struct disk_events *ev;
>  #ifdef  CONFIG_BLK_DEV_INTEGRITY
>  	struct kobject integrity_kobj;
> -- 
> 2.31.1

  Luis