softlockup happens in `acsc_status` function from the module `acdc`

Issue

• System was not responding and shows below soft lockup messages.

...
[2082966.713496] NMI watchdog: BUG: soft lockup - CPU#4 stuck for 22s! [dsp.ac.main:9646]
[2082966.714131] Modules linked in: gsch(OE) redirfs(OE) bmhook(OE) dsa_filter(POE) dsa_filter_hook(OE) nfnetlink_queue nfnetlink_log bluetooth rfkill xt_conntrack ipt_MASQUERADE nf_nat_masquerade_ipv4 nf_conntrack_netlink xt_addrtype iptable_filter iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack br_netfilter bridge stp llc overlay(T) acdc(OE) tmhook(OE) vmw_vsock_vmci_transport vsock ext4 mbcache jbd2 sb_edac iosf_mbi crc32_pclmul ppdev ghash_clmulni_intel vmw_balloon aesni_intel lrw gf128mul glue_helper ablk_helper cryptd joydev pcspkr sg parport_pc vmw_vmci parport i2c_piix4 binfmt_misc ip_tables xfs libcrc32c sr_mod cdrom ata_generic pata_acpi vmwgfx drm_kms_helper syscopyarea sysfillrect sd_mod sysimgblt fb_sys_fops ttm crc_t10dif crct10dif_generic drm ahci ata_piix crct10dif_pclmul
[2082966.714176]  crct10dif_common libahci crc32c_intel nfit libata serio_raw libnvdimm vmxnet3 vmw_pvscsi drm_panel_orientation_quirks dm_mirror dm_region_hash dm_log dm_mod fuse [last unloaded: dsa_filter_hook]
[2082966.714187] CPU: 4 PID: 9646 Comm: dsp.ac.main Kdump: loaded Tainted: P           OEL ------------ T 3.10.0-1160.31.1.el7.x86_64 #1
[2082966.714188] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020
[2082966.714190] task: ffff97b0d0412100 ti: ffff97b027bdc000 task.ti: ffff97b027bdc000
[2082966.714191] RIP: 0010:[<ffffffff89b1749d>]  [<ffffffff89b1749d>] native_queued_spin_lock_slowpath+0x1d/0x200
[2082966.714198] RSP: 0018:ffff97b027bdfd08  EFLAGS: 00000293
[2082966.714200] RAX: 0000000000000001 RBX: 0000000000000200 RCX: 0000000000000001
[2082966.714201] RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffffffffc09548d4
[2082966.714202] RBP: ffff97b027bdfd08 R08: ffffffffc094a940 R09: 0000000000000073
[2082966.714203] R10: 223a226b6f6f6822 R11: 223a226b6f6f6822 R12: ffff97b002a8b840
[2082966.714204] R13: ffffffffc064e3f4 R14: ffff97b027bdfc90 R15: ffff97b027bdfd18
[2082966.714206] FS:  00002b86be900700(0000) GS:ffff97a8dfd00000(0000) knlGS:0000000000000000
[2082966.714208] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[2082966.714209] CR2: 00002b86c1b179c0 CR3: 0000000f1e2a0000 CR4: 00000000000607e0
[2082966.714216] Call Trace:
[2082966.714224]  [<ffffffff8a17dd63>] queued_spin_lock_slowpath+0xb/0xf
[2082966.714229]  [<ffffffff8a18bb10>] _raw_spin_lock+0x20/0x30
[2082966.714233]  [<ffffffffc094c74d>] acsc_status+0x5d/0x220 [acdc]
[2082966.714237]  [<ffffffffc094ce20>] ? json_lex+0xd0/0x2b0 [acdc]
[2082966.714240]  [<ffffffffc094e46f>] ac_command.constprop.21+0x1cf/0x1e0 [acdc]
[2082966.714245]  [<ffffffff89bee949>] ? do_read_fault.isra.63+0x139/0x1b0
[2082966.714248]  [<ffffffffc094e7dd>] device_ioctl+0x35d/0x3e0 [acdc]
[2082966.714251]  [<ffffffffc094a940>] ? acsc_hook_status+0x190/0x190 [acdc]
[2082966.714255]  [<ffffffff89c635c0>] do_vfs_ioctl+0x3a0/0x5b0
[2082966.714259]  [<ffffffff8a190678>] ? __do_page_fault+0x238/0x500
[2082966.714261]  [<ffffffff89c63871>] SyS_ioctl+0xa1/0xc0
[2082966.714264]  [<ffffffff8a195f92>] system_call_fastpath+0x25/0x2a
[2082966.714267]  [<ffffffff8a195ed5>] ? system_call_after_swapgs+0xa2/0x13a
[2082966.714268] Code: 47 fe ff ff 66 2e 0f 1f 84 00 00 00 00 00 66 66 66 66 90 55 48 89 e5 66 90 b9 01 00 00 00 8b 17 85 d2 74 0d 83 fa 03 74 08 f3 90 <8b> 17 85 d2 75 f3 89 d0 f0 0f b1 0f 39 c2 75 e3 5d 66 90 c3 0f