nvme: don't send keep-alives to the discovery controller

NVMe over Fabrics 1.0 Section 5.2 "Discovery Controller Properties and
Command Support" Figure 31 "Discovery Controller – Admin Commands"
explicitly listst all commands but "Get Log Page" and "Identify" as
reserved, but NetApp report the Linux host is sending Keep Alive
commands to the discovery controller, which is a violation of the
Spec.

We're already checking for discovery controllers when configuring the
keep alive timeout but when creating a discovery controller we're not
hard wiring the keep alive timeout to 0 and thus remain on
NVME_DEFAULT_KATO for the discovery controller.

This can be easily remproduced when issuing a direct connect to the
discovery susbsystem using:
'nvme connect [...] --nqn=nqn.2014-08.org.nvmexpress.discovery'

Signed-off-by: Johannes Thumshirn <[email protected]>
Fixes: 07bfcd09a2 ("nvme-fabrics: add a generic NVMe over Fabrics library")
Reported-by: Martin George <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: Keith Busch <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
This commit is contained in:
Johannes Thumshirn 2018-04-12 09:16:06 -06:00 • committed by Jens Axboe
commit 74c6c71530

View file

@ -608,8 +608,10 @@ static int nvmf_parse_options(struct nvmf_ctrl_options *opts,
opts->discovery_nqn =
!(strcmp(opts->subsysnqn,
NVME_DISC_SUBSYS_NAME));
if (opts->discovery_nqn)
if (opts->discovery_nqn) {
opts->kato = 0;
opts->nr_io_queues = 0;
}
break;
case NVMF_OPT_TRADDR:
p = match_strdup(args);