RHEL8: Soft lockup at scan_swap_map_try_ssd_cluster()

Issue

• Soft lockup occurred with logs:

[181421.172388] watchdog: BUG: soft lockup - CPU#11 stuck for 67s! [kswapd0:243]
[181421.173578] Modules linked in: vfat fat crct10dif_ce ghash_ce sha2_ce sha256_arm64 sha1_ce xfs libcrc32c nvme ena nvme_core dm_mirror dm_region_hash dm_log dm_mod ipmi_devintf ipmi_msghandler
[181421.176339] CPU: 11 PID: 243 Comm: kswapd0 Kdump: loaded Not tainted 4.18.0-372.32.1.el8_6.aarch64 #1
[181421.177868] Hardware name: Amazon EC2 m6g.4xlarge/, BIOS 1.0 11/1/2018
[181421.178955] pstate: 20c00005 (nzCv daif +PAN +UAO)
[181421.179759] pc : scan_swap_map_try_ssd_cluster+0x50/0x190
[181421.180678] lr : scan_swap_map_slots+0xa0/0x8d0
[181421.181439] sp : ffff80001b28f770
[181421.182011] x29: ffff80001b28f770 x28: ffffbce771605a10 
[181421.182898] x27: 0000000002000000 x26: ffff68a31b8a2000 
[181421.183779] x25: ffff68a31b8a2000 x24: fffffbdfffce72d8 
[181421.184669] x23: 0000000000000000 x22: ffff80001b28f860 
[181421.185561] x21: ffff80001b28f858 x20: 000000000001f2ba 
[181421.186464] x19: 000000000001f300 x18: ffffbce770e38788 
[181421.187357] x17: fffffffa2c7b1980 x16: ffffbce76f696138 
[181421.188270] x15: 0000000000000001 x14: fffffffa27a00000 
[181421.189156] x13: 0000000002000001 x12: ffffffdfffe00000 
[181421.190034] x11: 0000000000000000 x10: ffff68b26d7ee580 
[181421.190941] x9 : 000000000000001d x8 : 0000000000000001 
[181421.191864] x7 : ffffbce771605000 x6 : 00000000ffffffce 
[181421.192768] x5 : 0000000460c10000 x4 : ffff68a307ecc980 
[181421.193660] x3 : ffff68a31b071c00 x2 : 0000000000000002 
[181421.194560] x1 : ffffabcafcab0000 x0 : 00005015032372d8 
[181421.195447] Call trace:
[181421.195869]  scan_swap_map_try_ssd_cluster+0x50/0x190
[181421.196724]  scan_swap_map_slots+0xa0/0x8d0
[181421.197440]  get_swap_pages+0x2c8/0x388
[181421.198108]  get_swap_page+0x114/0x218
[181421.198760]  add_to_swap+0x24/0x90
[181421.199346]  shrink_page_list+0x8d0/0xc30
[181421.200036]  shrink_inactive_list+0x1dc/0x490
[181421.200780]  shrink_lruvec+0x3b0/0x5b8
[181421.201413]  shrink_node+0x3d0/0x700
[181421.202042]  balance_pgdat+0x2f4/0x5d0
[181421.202705]  kswapd+0x1bc/0x458
[181421.203259]  kthread+0x128/0x138
[181421.203814]  ret_from_fork+0x10/0x18
[181421.204432] Kernel panic - not syncing: softlockup: hung tasks
[181421.205414] CPU: 11 PID: 243 Comm: kswapd0 Kdump: loaded Tainted: G             L   --------- -  - 4.18.0-372.32.1.el8_6.aarch64 #1
[181421.207337] Hardware name: Amazon EC2 m6g.4xlarge/, BIOS 1.0 11/1/2018
[181421.208432] Call trace:
[181421.208868]  dump_backtrace+0x0/0x160
[181421.209496]  show_stack+0x28/0x38
[181421.210066]  dump_stack+0x5c/0x74
[181421.210628]  panic+0x140/0x30c
[181421.211164]  watchdog_timer_fn+0x264/0x290
[181421.211848]  __hrtimer_run_queues+0x114/0x358
[181421.212578]  hrtimer_interrupt+0x118/0x2d0
[181421.213267]  arch_timer_handler_virt+0x40/0x50
[181421.214027]  handle_percpu_devid_irq+0x94/0x240
[181421.214798]  generic_handle_irq+0x40/0x58
[181421.215463]  __handle_domain_irq+0x70/0xc8
[181421.216148]  gic_handle_irq+0xd8/0x17c
[181421.216788]  el1_irq+0xb8/0x140
[181421.217328]  scan_swap_map_try_ssd_cluster+0x50/0x190
[181421.218157]  scan_swap_map_slots+0xa0/0x8d0
[181421.218855]  get_swap_pages+0x2c8/0x388
[181421.219497]  get_swap_page+0x114/0x218
[181421.220120]  add_to_swap+0x24/0x90
[181421.220695]  shrink_page_list+0x8d0/0xc30
[181421.221346]  shrink_inactive_list+0x1dc/0x490
[181421.222080]  shrink_lruvec+0x3b0/0x5b8
[181421.222716]  shrink_node+0x3d0/0x700
[181421.223329]  balance_pgdat+0x2f4/0x5d0
[181421.223959]  kswapd+0x1bc/0x458
[181421.224520]  kthread+0x128/0x138
[181421.225092]  ret_from_fork+0x10/0x18
[181421.225726] SMP: stopping secondary CPUs
[181421.227913] Starting crashdump kernel...
[181421.228569] Bye!