nvme-multipath: fix suspicious RCU usage warning

In the Linux kernel, the following vulnerability has been resolved:

nvme-multipath: fix suspicious RCU usage warning

When I run the NVME over TCP test in virtme-ng, I get the following

"suspicious RCU usage" warning in nvme_mpath_add_sysfs_link():

'''

[ 5.024557][ T44] nvmet: Created nvm controller 1 for subsystem nqn.2025-06.org.nvmexpress.mptcp for NQN nqn.2014-08.org.nvmexpress:uuid:f7f6b5e0-ff97-4894-98ac-c85309e0bc77.

[ 5.027401][ T183] nvme nvme0: creating 2 I/O queues.

[ 5.029017][ T183] nvme nvme0: mapped 2/0/0 default/read/poll queues.

[ 5.032587][ T183] nvme nvme0: new ctrl: NQN "nqn.2025-06.org.nvmexpress.mptcp", addr 127.0.0.1:4420, hostnqn: nqn.2014-08.org.nvmexpress:uuid:f7f6b5e0-ff97-4894-98ac-c85309e0bc77

[ 5.042214][ T25]

[ 5.042440][ T25] =============================

[ 5.042579][ T25] WARNING: suspicious RCU usage

[ 5.042705][ T25] 6.16.0-rc3+ #23 Not tainted

[ 5.042812][ T25] -----------------------------

[ 5.042934][ T25] drivers/nvme/host/multipath.c:1203 RCU-list traversed in non-reader section!!

[ 5.043111][ T25]

[ 5.043111][ T25] other info that might help us debug this:

[ 5.043111][ T25]

[ 5.043341][ T25]

[ 5.043341][ T25] rcu_scheduler_active = 2, debug_locks = 1

[ 5.043502][ T25] 3 locks held by kworker/u9:0/25:

[ 5.043615][ T25] #0: ffff888008730948 ((wq_completion)async){+.+.}-{0:0}, at: process_one_work+0x7ed/0x1350

[ 5.043830][ T25] #1: ffffc900001afd40 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: process_one_work+0xcf3/0x1350

[ 5.044084][ T25] #2: ffff888013ee0020 (&head->srcu){.+.+}-{0:0}, at: nvme_mpath_add_sysfs_link.part.0+0xb4/0x3a0

[ 5.044300][ T25]

[ 5.044300][ T25] stack backtrace:

[ 5.044439][ T25] CPU: 0 UID: 0 PID: 25 Comm: kworker/u9:0 Not tainted 6.16.0-rc3+ #23 PREEMPT(full)

[ 5.044441][ T25] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011

[ 5.044442][ T25] Workqueue: async async_run_entry_fn

[ 5.044445][ T25] Call Trace:

[ 5.044446][ T25] <TASK>

[ 5.044449][ T25] dump_stack_lvl+0x6f/0xb0

[ 5.044453][ T25] lockdep_rcu_suspicious.cold+0x4f/0xb1

[ 5.044457][ T25] nvme_mpath_add_sysfs_link.part.0+0x2fb/0x3a0

[ 5.044459][ T25] ? queue_work_on+0x90/0xf0

[ 5.044461][ T25] ? lockdep_hardirqs_on+0x78/0x110

[ 5.044466][ T25] nvme_mpath_set_live+0x1e9/0x4f0

[ 5.044470][ T25] nvme_mpath_add_disk+0x240/0x2f0

[ 5.044472][ T25] ? __pfx_nvme_mpath_add_disk+0x10/0x10

[ 5.044475][ T25] ? add_disk_fwnode+0x361/0x580

[ 5.044480][ T25] nvme_alloc_ns+0x81c/0x17c0

[ 5.044483][ T25] ? kasan_quarantine_put+0x104/0x240

[ 5.044487][ T25] ? __pfx_nvme_alloc_ns+0x10/0x10

[ 5.044495][ T25] ? __pfx_nvme_find_get_ns+0x10/0x10

[ 5.044496][ T25] ? rcu_read_lock_any_held+0x45/0xa0

[ 5.044498][ T25] ? validate_chain+0x232/0x4f0

[ 5.044503][ T25] nvme_scan_ns+0x4c8/0x810

[ 5.044506][ T25] ? __pfx_nvme_scan_ns+0x10/0x10

[ 5.044508][ T25] ? find_held_lock+0x2b/0x80

[ 5.044512][ T25] ? ktime_get+0x16d/0x220

[ 5.044517][ T25] ? kvm_clock_get_cycles+0x18/0x30

[ 5.044520][ T25] ? __pfx_nvme_scan_ns_async+0x10/0x10

[ 5.044522][ T25] async_run_entry_fn+0x97/0x560

[ 5.044523][ T25] ? rcu_is_watching+0x12/0xc0

[ 5.044526][ T25] process_one_work+0xd3c/0x1350

[ 5.044532][ T25] ? __pfx_process_one_work+0x10/0x10

[ 5.044536][ T25] ? assign_work+0x16c/0x240

[ 5.044539][ T25] worker_thread+0x4da/0xd50

[ 5.044545][ T25] ? __pfx_worker_thread+0x10/0x10

[ 5.044546][ T25] kthread+0x356/0x5c0

[ 5.044548][ T25] ? __pfx_kthread+0x10/0x10

[ 5.044549][ T25] ? ret_from_fork+0x1b/0x2e0

[ 5.044552][ T25] ? __lock_release.isra.0+0x5d/0x180

[ 5.044553][ T25] ? ret_from_fork+0x1b/0x2e0

[ 5.044555][ T25] ? rcu_is_watching+0x12/0xc0

[ 5.044557][ T25] ? __pfx_kthread+0x10/0x10

[ 5.04

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