Re: [PATCH 2/2] nvme: add 'queue_if_no_path' semantics
From: Sagi Grimberg <sagi@grimberg.me>
Date: 2021-03-05 20:11:30
quoted hunk ↗ jump to hunk
I think what you're showing is a problem for everyone, including fabrics. The namespace was attached to the previously existing subsystem, nvme1, but we didn't find the previously existing "head" to reattach the namespace. I just threw the below together very hastily, so I'm sure there's something wrong with it, but just to capture what's wrong with the current code: ---diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 3833584b5cee..0b3bbbe6d1e8 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c@@ -3897,8 +3897,6 @@ static void nvme_ns_remove(struct nvme_ns *ns) mutex_lock(&ns->ctrl->subsys->lock); list_del_rcu(&ns->siblings); - if (list_empty(&ns->head->list)) - list_del_init(&ns->head->entry);
Not removing it ever from the head->list?
mutex_unlock(&ns->ctrl->subsys->lock); synchronize_rcu(); /* guarantee not available in head->list */ --
This is a problem. beacuse if you don't remove the ns from the head->list nothing prevents it from being re-selected as the current_path after we synchronize the srcu, although it is going away... _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme