[Devel] [PATCH hci-8.1 v3 4/6] drivers/md/push_backup: fix mod_timer() usage

[Alexander Ivanov]

On 11/3/26 07:17, Andrey Zhadchenko wrote:
> mod_timer() takes an absolute jiffies value, but both callers pass a
> relative one. After about 5 min uptime this causes the timer to fire
> and re-arm on every tick. This has not exploded because we still have
> checked pb->deadline_jiffies each time.
>
> https://virtuozzo.atlassian.net/browse/VSTOR-152912
Fixes: 62e07487348e ("dm: Add push backup driver")
> Signed-off-by: Andrey Zhadchenko <andrey.zhadchenko at virtuozzo.com>
> ---
> v2: no changes
> v3: no changes
>
>   drivers/md/dm-push-backup.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/md/dm-push-backup.c b/drivers/md/dm-push-backup.c
> index 8ce84a1a696e5..b1861204f6e3e 100644
> --- a/drivers/md/dm-push-backup.c
> +++ b/drivers/md/dm-push-backup.c
> @@ -244,7 +244,7 @@ static void pb_timer_func(struct timer_list *timer)
>   	spin_unlock_irqrestore(&pb->lock, flags);
>   
>   	if (unlikely(time_before64(now, deadline)))
> -		mod_timer(timer, deadline - now + 1);
> +		mod_timer(timer, jiffies + (deadline - now) + 1);
>   	else
>   		queue_work(pb->wq, &pb->worker);
>   }
> @@ -278,7 +278,7 @@ static int postpone_if_required_for_backup(struct push_backup *pb,
>   	spin_unlock_irqrestore(&pb->lock, flags);
>   
>   	if (queue_timer)
> -		mod_timer(&pb->deadline_timer, pb->timeout_in_jiffies + 1);
> +		mod_timer(&pb->deadline_timer, jiffies + pb->timeout_in_jiffies + 1);
>   	rcu_read_unlock();
>   
>   	if (queue_timer)