NULL pointer dereference often happens in rcu_segcblist_enqueue() with a "delete_controller" command being performed on a nvme controller

Issue

• null-deref crash often happens in rcu_segcblist_enqueue() with a "delete_controller" command being performed on a nvme controller.

[454339.774039] nvme nvme1: Property Set error: -4, offset 0x14
[454339.780850] BUG: kernel NULL pointer dereference, address: 0000000000000000
[454339.791467] #PF: supervisor write access in kernel mode
[454339.798812] #PF: error_code(0x0002) - not-present page
[454339.807549] PGD 8000000343e47067 P4D 8000000343e47067 PUD 403c1d067 PMD 0 
[454339.817900] Oops: 0002 [#1] PREEMPT SMP PTI
[454339.825574] CPU: 27 PID: 3749920 Comm: sdt-4.5.0.260 Kdump: loaded Tainted: P        W IOE    --------  ---  5.14.0-284.18.1.el9_2.x86_64 #1
[454339.844957] Hardware name: Dell Inc. VxFlex-R740xd/01KPX8, BIOS 1.4.5 03/30/2018
[454339.855833] RIP: 0010:rcu_segcblist_enqueue+0x22/0x30
[454339.863853] Code: c3 cc cc cc cc 0f 1f 00 0f 1f 44 00 00 f0 48 83 47 48 01 48 8b 47 68 48 83 c0 01 48 89 47 68 48 c7 06 00 00 00 00 48 8b 47 20 <48> 89 30 48 89 77 20 c3 cc cc cc cc 66 90 0f 1f 44 00 00 48 8b 57
[454339.889893] RSP: 0018:ffff9c51280bfc58 EFLAGS: 00010002
[454339.898669] RAX: 0000000000000000 RBX: ffff8d8801e2a638 RCX: 0000000000000002
[454339.908524] RDX: 0000000000000001 RSI: ffff9c51280bfcb0 RDI: ffff8d8210000048
[454339.919308] RBP: ffff8d8210000000 R08: ffff8d9e0fb6b638 R09: ffff8d9e0fb6b638
[454339.930097] R10: 00000000000001b0 R11: 0000000000007410 R12: 0000000000000000
[454339.939884] R13: ffff9c51280bfcb0 R14: 0000000000000286 R15: ffff8d8210000040
[454339.950619] FS:  00007f1895d2b640(0000) GS:ffff8d9e0fb40000(0000) knlGS:0000000000000000
[454339.962279] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[454339.970788] CR2: 0000000000000000 CR3: 000000036829a001 CR4: 00000000007706e0
[454339.981508] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[454339.992243] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[454340.002674] PKRU: 55555554
[454340.008726] Call Trace:
[454340.014632]  <TASK>
[454340.019560]  srcu_gp_start_if_needed+0xe2/0x1e0
[454340.027377]  __synchronize_srcu.part.0+0x75/0xf0
[454340.034917]  ? __bpf_trace_rcu_stall_warning+0x10/0x10
[454340.043238]  nvme_tcp_delete_ctrl+0x34/0x70 [nvme_tcp]
[454340.051158]  nvme_do_delete_ctrl+0x63/0x6f [nvme_core]
[454340.059483]  nvme_sysfs_delete.cold+0x8/0xd [nvme_core]
[454340.067399]  kernfs_fop_write_iter+0x121/0x1b0
[454340.074926]  new_sync_write+0xfc/0x190
[454340.081729]  vfs_write+0x1ef/0x280
[454340.088065]  ksys_write+0x5f/0xe0
[454340.094228]  do_syscall_64+0x59/0x90
[454340.100151]  ? handle_mm_fault+0xc5/0x2a0
[454340.106935]  ? do_user_addr_fault+0x1d8/0x690
[454340.113903]  ? exc_page_fault+0x62/0x150
[454340.120442]  entry_SYSCALL_64_after_hwframe+0x63/0xcd
[454340.128146] RIP: 0033:0x7f18b433ebcf
[454340.134375] Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 39 d0 f5 ff 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 8c d0 f5 ff 48
[454340.158235] RSP: 002b:00007f1895d2a000 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
[454340.168485] RAX: ffffffffffffffda RBX: 00007f1895d2b640 RCX: 00007f18b433ebcf
[454340.177878] RDX: 0000000000000001 RSI: 0000000000d61874 RDI: 0000000000000035
[454340.187681] RBP: 00007f1895d2a060 R08: 0000000000000000 R09: 00000000ffffffff
[454340.197454] R10: 0000000000000000 R11: 0000000000000293 R12: 00007f1895d2b640
[454340.207222] R13: 0000000000000000 R14: 00007f18b429f530 R15: 0000000000000001
[454340.216973]  </TASK>
[454340.221732] Modules linked in: [...]
[454340.222032]  [last unloaded: ...]
[454340.317156] CR2: 0000000000000000