[Devel] [PATCH vz10 13/24] dm-tracking: initialize dmt->lock with spin_lock_init()

[Pavel Tikhomirov]

Reviewed-by: Pavel Tikhomirov <ptikhomirov at virtuozzo.com>

On 7/6/26 12:59, Konstantin Khorenko wrote:
> struct dm_tracking is allocated with kzalloc() and its embedded
> spinlock dmt->lock is taken in dmt_status()/tracking_clear()/
> tracking_get_next()/dmt_cmd(), but dmt_ctr() never runs
> spin_lock_init() on it (only ctl_mutex is initialized). A zero-filled
> spinlock has no static lockdep key, so on the first spin_lock_irq() a
> lockdep kernel prints:
> 
>   INFO: trying to register non-static key.
>   ... turning off the locking correctness validator.
>   _raw_spin_lock_irq <- dmt_status <- dm_ima_measure_on_table_load
>     <- table_load <- ctl_ioctl
> 
> and disables lockdep for the rest of the boot. Initialize the spinlock
> in the constructor next to mutex_init(&dmt->ctl_mutex).
> 
> Fixes: 51958806db7e ("dm: Add dm-tracking target")
> Feature: dm-tracking: dirty blocks tracking target driver (for migration)
> https://virtuozzo.atlassian.net/browse/VSTOR-137234
> Signed-off-by: Konstantin Khorenko <khorenko at virtuozzo.com>
> ---
>  drivers/md/dm-tracking.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/md/dm-tracking.c b/drivers/md/dm-tracking.c
> index ff0ba1cc5510..9b387a92f9a9 100644
> --- a/drivers/md/dm-tracking.c
> +++ b/drivers/md/dm-tracking.c
> @@ -153,6 +153,7 @@ static int dmt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
>  		goto err;
>  
>  	mutex_init(&dmt->ctl_mutex);
> +	spin_lock_init(&dmt->lock);
>  
>  	ti->private = dmt;
>  	dmt->ti = ti;

-- 
Best regards, Pavel Tikhomirov
Senior Software Developer, Virtuozzo.