Commit 2b36209c authored by Bart Van Assche's avatar Bart Van Assche Committed by Martin K. Petersen
Browse files

scsi: core: Revert "Call blk_mq_free_tag_set() earlier" 

Revert the patch series "Call blk_mq_free_tag_set() earlier" because it
introduces a deadlock if the scsi_remove_host() caller holds a reference on
a device, target or host.

Link: https://lore.kernel.org/r/20220821220502.13685-2-bvanassche@acm.org


Fixes: f323896f ("scsi: core: Call blk_mq_free_tag_set() earlier")
Reported-by: default avatar <syzbot+bafeb834708b1bb750bc@syzkaller.appspotmail.com>
Tested-by: default avatarKenneth R. Crudup <kenny@panix.com>
Signed-off-by: default avatarBart Van Assche <bvanassche@acm.org>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent da6d507f

drivers/scsi/hosts.c

+5 −5
Original line number Diff line number Diff line
@@ -197,8 +197,6 @@ void scsi_remove_host(struct Scsi_Host *shost) 
	 * the dependent SCSI targets and devices are gone before returning.

	 */

	wait_event(shost->targets_wq, atomic_read(&shost->target_count) == 0);



	scsi_mq_destroy_tags(shost);

}

EXPORT_SYMBOL(scsi_remove_host);
@@ -309,8 +307,8 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev, 
	return error;



	/*

	 * Any resources associated with the SCSI host in this function except

	 * the tag set will be freed by scsi_host_dev_release().

	 * Any host allocation in this function will be freed in

	 * scsi_host_dev_release().

	 */

 out_del_dev:

	device_del(&shost->shost_dev);
@@ -326,7 +324,6 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev, 
	pm_runtime_disable(&shost->shost_gendev);

	pm_runtime_set_suspended(&shost->shost_gendev);

	pm_runtime_put_noidle(&shost->shost_gendev);

	scsi_mq_destroy_tags(shost);

 fail:

	return error;

}
@@ -360,6 +357,9 @@ static void scsi_host_dev_release(struct device *dev) 
		kfree(dev_name(&shost->shost_dev));

	}



	if (shost->tag_set.tags)

		scsi_mq_destroy_tags(shost);



	kfree(shost->shost_data);



	ida_free(&host_index_ida, shost->host_no);