Comment 2 for bug 1946220

Full stack trace from console:
[ 256.441780] Unable to handle kernel read from unreadable memory at virtual address 00000050
[ 256.450170] Mem abort info:
[ 256.441780] Unable to handle k[ 256.452976] ESR = 0x96000004
ernel read from unreadable memory at virtual address 00000050
[ 256.450170] Mem abort info:
[ 256.452976] ESR = 0x96000004
[ 256.470173] Exception class = DABT (current EL), IL = 32 bits
[ 256.476104] SET = 0, FnV = 0
[ 256.479165] EA = 0, S1PTW = 0
[ 256.470173] Exception class [ 256.482320] Data abort info:
= DABT (current EL), IL = 32 bits[ 256.488044] ISV = 0, ISS = 0x00000004

[ 256.494733] C[M =2 506,. WnR = 0
476104] SET = 0, FnV = 0
[ 256.479165] EA = 0, S1PTW = 0
[ 256.482320] Data abort info:
[ 256.488044] ISV = 0, ISS = 0x00000004
[ 256.494733] CM = 0, WnR = 0
[ 256.513652] user pgtable: 4k pages, 48-bit VAs, pgd = 00000000cea29530
[ 256.520183] [0000000000000050] *pgd=0000000000000000
[ 256.513652] user [p g t2a5b6l.525156] Internal error: Oops: 96000004 [#1] SMP
e: 4k pages, 48-bit VAs, pgd = 00000000cea29530
[ 256.520183] [0000000000000050] *pgd=0000000000000000
[ 256.525156] Internal error: Oops: 96000004 [#1] SMP
[ 256.546331] Modules linked in: binfmt_misc ipmi_ssif nls_iso8859_1 joydev input_leds ipmi_si ipmi_devintf ipmi_msghandler shpchp sch_fq_codel ib_iser rdma_cm iw_cm ib_cm iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ip_tables x_tables autofs4 btrfs zstd_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 multipath linear mlx5_ib hid_generic usbhid hid ib_core marvell ses enclosure hibmc_drm ttm aes_ce_blk mlx5_core aes_ce_cipher crc32_ce drm_kms_helper ixgbe crct10dif_ce mlxfw ghash_ce syscopyarea devlink sysfillrect sha2_ce sysimgblt sha256_arm64 fb_sys_fops nvme hisi_sas_v2_hw ptp sha1_ce drm hisi_sas_main megaraid_sas mdio nvme_core pps_core libsas ehci_platform hns_dsaf scsi_transport_sas hns_enet_drv hns_mdio hnae aes_neon_bs
[ 256.617376] aes_neon_blk crypto_simd cryptd aes_arm64
[ 256.622504] Process swapper/60 (pid: 0, stack limit = 0x00000000fab7ae5e)
[ 256.629281] CPU: 60 PID: 0 Comm: swapper/60 Not tainted 4.15.0-159-generic #167-Ubuntu
[ 256.637184] Hardware name: Hisilicon D05/BC11SPCD, BIOS 1.50 06/01/2018
[ 256.643785] pstate: 00400005 (nzcv daif +PAN -UAO)
[ 256.648567] pc : trace_event_raw_event_wbt_timer+0xa0/0xf8
[ 256.654039] lr : trace_event_raw_event_wbt_timer+0x90/0xf8
[ 256.659510] sp : ffff0000099e3cb0
[ 256.662812] x29: ffff0000099e3cb0 x28: 0000000000000282
[ 256.668112] x27: 0000000000000002 x26: ffff0000095a5188
[ 256.673411] x25: ffff801fb06a4800 x24: 0000000000000003
[ 256.678710] x23: 0000000000000000 x22: 0000000000000000
[ 256.684008] x21: ffff801fba1110b0 x20: ffff80afa7356c7c
[ 256.689307] x19: ffff0000095a8000 x18: 0000ffffb05a2a70
[ 256.694605] x17: 0000000000002c80 x16: 0000000000000000
[ 256.699904] x15: 0000000000000000 x14: ffff000008b97c00
[ 256.705203] x13: 0000000000000000 x12: 0000000000000000
[ 256.710501] x11: ffffffffffffffff x10: 0000000000009ad8
[ 256.715800] x9 : 0000000000000c68 x8 : ffff80afb7516400
[ 256.721099] x7 : 0000000000000034 x6 : ffff80afa7356c78
[ 256.726397] x5 : ffff0000099e3c10 x4 : 0000000000000008
[ 256.731696] x3 : 0000000000000020 x2 : 0000000000000000
[ 256.736994] x1 : 000000000000000d x0 : ffff80afa7356c84
[ 256.742294] Call trace:
[ 256.744729] trace_event_raw_event_wbt_timer+0xa0/0xf8
[ 256.749854] wb_timer_fn+0x1f0/0x450
[ 256.753417] blk_stat_timer_fn+0x168/0x180
[ 256.757501] call_timer_fn+0x34/0x178
[ 256.761151] expire_timers+0xc8/0x130
[ 256.764800] run_timer_softirq+0xec/0x1b8
[ 256.768797] __do_softirq+0x134/0x348
[ 256.772448] irq_exit+0xcc/0xe0
[ 256.775577] __handle_domain_irq+0x6c/0xc0
[ 256.779660] gic_handle_irq+0x84/0x180
[ 256.783396] el1_irq+0xe8/0x180
[ 256.786524] arch_cpu_idle+0x30/0x180
[ 256.790174] do_idle+0x138/0x1f0
[ 256.793390] cpu_startup_entry+0x2c/0x40
[ 256.797300] secondary_start_kernel+0x114/0x128
[ 256.801820] Code: aa0003f4 b4fffde0 f941cf22 91002000 (f9402841)
[ 256.807972] ---[ end trace 9cd4ceccdf6d5253 ]---
[ 256.812577] Kernel panic - not syncing: Fatal exception in interrupt
[ 256.818931] SMP: stopping secondary CPUs
[ 256.822868] Kernel Offset: disabled
[ 256.826344] CPU features: 0x00002008
[ 256.829907] Memory Limit: none
[ 256.832964] ---[ end Kernel panic - not syncing: Fatal exception in interrupt