nvme: reject passthrough of driver-managed Set Features

Since commit b58da2d270db ("nvme: update keep alive interval when kato
is modified"), a Set Features (KATO) passthrough command lets userspace
start keep-alive on any transport. nvme_keep_alive_work() allocates with
BLK_MQ_REQ_RESERVED, but nvme_alloc_admin_tag_set() reserves admin tags
only for fabrics, so on other transports the allocation trips
WARN_ON_ONCE() in blk_mq_get_tag() and fails:

  nvme nvme0: keep-alive failed: -11

Several Set Features change controller state the driver manages itself
and cannot react to when set behind its back. Reject these in
nvme_admin_cmd_allowed():

  - KATO on non-fabrics (keep-alive is only armed for fabrics; on PCIe
    it has no reserved tag and harms idle power states)
  - Host Behavior Support, Host Memory Buffer, Number of Queues, and
    Autonomous Power State Transition (all driver-managed)

Keep Alive on fabrics is unchanged; I/O commands are unaffected as the
check is confined to the admin path (ns == NULL).

Link: https://lore.kernel.org/linux-nvme/20260523225629.3964037-1-coshi036@gmail.com/

Fixes: b58da2d270db ("nvme: update keep alive interval when kato is modified")

Found by FuzzNvme.

Acked-by: Sungwoo Kim <iam@sung-woo.kim>
Acked-by: Dave Tian <daveti@purdue.edu>
Acked-by: Weidong Zhu <weizhu@fiu.edu>
Signed-off-by: Chao Shi <coshi036@gmail.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>

0 files changed, 0 insertions, 0 deletions