Re: [PATCH v6 02/23] ata: libata-core: Fix port and device removal

[Bart Van Assche <bvanassche@acm.org>]

On 9/22/23 17:29, Damien Le Moal wrote:
> Also delete the WAR_ON() call checking that the ATA_PFLAG_UNLOADING flag
> was cleared as that is done without holding the port lock.

Hmm ... I don't see any WARN_ON() statement being removed by this patch?

> -	/* tell EH we're leaving & flush EH */
> +	/* Wait for any ongoing EH */
> +	ata_port_wait_eh(ap);
> +
> +	mutex_lock(&ap->scsi_scan_mutex);
>   	spin_lock_irqsave(ap->lock, flags);
> +
> +	/* Remove scsi devices */
> +	ata_for_each_link(link, ap, HOST_FIRST) {
> +		ata_for_each_dev(dev, link, ALL) {
> +			if (dev->sdev) {
> +				spin_unlock_irqrestore(ap->lock, flags);
> +				scsi_remove_device(dev->sdev);
> +				spin_lock_irqsave(ap->lock, flags);
> +				dev->sdev = NULL;
> +			}
> +		}
> +	}

Can the lists ata_for_each_link() and ata_for_each_dev() iterate over change
while ap->lock is unlocked? If not, does this perhaps have to be explained in
a comment? If these lists can be changed, should these lists perhaps be examined
from the start after every unlock of ap->lock?

Thanks,

Bart.