Re: [PATCH] nvme-rdma: fix crash for no IO queues
From: Hannes Reinecke <hare@suse.de>
Date: 2021-03-02 07:48:27
On 2/27/21 10:30 AM, Chao Leng wrote:
On 2021/2/27 17:12, Hannes Reinecke wrote:quoted
On 2/24/21 6:59 AM, Chao Leng wrote:quoted
On 2021/2/24 7:21, Keith Busch wrote:quoted
On Tue, Feb 23, 2021 at 03:26:02PM +0800, Chao Leng wrote:quoted
A crash happens when set feature(NVME_FEAT_NUM_QUEUES) timeout in nvme over rdma(roce) reconnection, the reason is use the queue which is not alloced. If it is not discovery and no io queues, the connection should fail.If you're getting a timeout, we need to quit initialization. Hannes attempted making that status visible for fabrics here: http://lists.infradead.org/pipermail/linux-nvme/2021-January/022353.htmlI know the patch. It can not solve the scenario: target may be an attacker or the target behavior is incorrect. If target return 0 io queues or return other error code, the crash will still happen. We should not allow this to happen.I'm fully with you that we shouldn't crash, but at the same time a value of '0' for the number of I/O queues is considered valid. So we should fix the code to handle this scenario, and not disallowing zero I/O queues.'0' I/O queues doesn't make any sense to nvme over fabrics, it is different with nvme over pci. If there is some bug with target, we can debug it in target instead of use admin queue in host. target may be an attacker or the target behavior is incorrect. So we should avoid crash. Another option: prohibit request delivery if io queue do not created. I think failed connection with '0' I/O queues is a better choice.
Might be, but that's not for me to decide. I tried that initially, but that patch got rejected as _technically_ the controller is reachable via its admin queue. Sagi? Christoph? Are controllers with 0 I/O queues valid or is this an error condition? Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@suse.de +49 911 74053 688 SUSE Software Solutions Germany GmbH, Maxfeldstr. 5, 90409 Nürnberg HRB 36809 (AG Nürnberg), GF: Felix Imendörffer _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme