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.
Reported-by: syzbot+bafeb834708b1bb750bc@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: f323896fe6fa ("scsi: core: Call blk_mq_free_tag_set() earlier")
Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx>
---
drivers/scsi/hosts.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c
index 0738238ed6cc..20c1f5420ba6 100644
--- a/drivers/scsi/hosts.c
+++ b/drivers/scsi/hosts.c
@@ -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);
