linux-kernel - Re: [PATCH v3 0/2] nvme-fabrics: short-circuit connect retries

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <432a39d5-6d08-4d38-a357-7c8d9123189a@grimberg.me>
Date: Thu, 7 Mar 2024 13:30:00 +0200
From: Sagi Grimberg <sagi@...mberg.me>
To: Hannes Reinecke <hare@...e.de>, Daniel Wagner <dwagner@...e.de>,
 James Smart <james.smart@...adcom.com>
Cc: Keith Busch <kbusch@...nel.org>, Christoph Hellwig <hch@....de>,
 linux-nvme@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v3 0/2] nvme-fabrics: short-circuit connect retries



On 07/03/2024 12:37, Hannes Reinecke wrote:
> On 3/7/24 09:00, Sagi Grimberg wrote:
>>
>> On 05/03/2024 10:00, Daniel Wagner wrote:
>>> I've picked up Hannes' DNR patches. In short the make the transports 
>>> behave the same way when the DNR bit set on a re-connect attempt. We
>>> had a discussion this
>>> topic in the past and if I got this right we all agreed is that the 
>>> host should honor the DNR bit on a connect attempt [1]
>> Umm, I don't recall this being conclusive though. The spec ought to 
>> be clearer here I think.
>
> I've asked the NVMexpress fmds group, and the response was pretty 
> unanimous that the DNR bit on connect should be evaluated.

OK.

>
>>>
>>> The nvme/045 test case (authentication tests) in blktests is a good 
>>> test case for this after extending it slightly. TCP and RDMA try to
>>> reconnect with an
>>> invalid key over and over again, while loop and FC stop after the 
>>> first fail.
>>
>> Who says that invalid key is a permanent failure though?
>>
> See the response to the other patchset.
> 'Invalid key' in this context means that the _client_ evaluated the 
> key as invalid, ie the key is unusable for the client.
> As the key is passed in via the commandline there is no way the client
> can ever change the value here, and no amount of retry will change 
> things here. That's what we try to fix.

Where is this retried today, I don't see where connect failure is 
retried, outside of a periodic reconnect.
Maybe I'm missing where what is the actual failure here.