Hello, I apologize for not replying to the original thread, I was not subscribed to this list when it was sent. I am having a nearly identical issue to Tomas Hlavaty, however I don't think it was caused by corruption or an unclean shutdown. Immediately after upgrading my kernel to 5.3.11 I rebooted, and received a similar message (included below). Rolling the kernel back to 5.2.10 (the oldest I had easily available) made the system boot-able again. The full message/trace is below: [ 6.274360] NILFS version 2 loaded [ 6.275461] NILFS (dm-2): mounting unchecked fs [ 6.316889] NILFS (dm-2): recovery complete [ 6.318609] NILFS (dm-2): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds [ 6.524132] systemd[1]: Successfully credited entropy passed from boot loader. [ 6.527313] systemd[1]: systemd 243.78-2-arch running in system mode. (+PAM +AUDIT -SELINUX -IMA -APPARMOR +SMACK -SYSVINIT +UTMP +LIBCRYPTSETUP +GCRYPT +GNUTLS +ACL +XZ +LZ4 +SECCOMP +BLKID +ELFUTILS +KMOD +IDN2 -IDN +PCRE2 default-hierarchy=hybrid) [ 6.539380] systemd[1]: Detected architecture x86-64. [ 6.545163] systemd[1]: Set hostname to <lap.waltonhoops.com>. [ 6.770464] systemd[1]: Started Emergency Shell. [ 6.770916] systemd[1]: Reached target Emergency Mode. [ 6.771425] systemd[349]: emergency.service: Executable /bin/plymouth missing, skipping: No such file or directory [ 6.772146] systemd[1]: Startup finished in 6.953s (firmware) + 4.746s (loader) + 6.469s (kernel) + 299ms (userspace) = 18.469s. [ 21.698147] BUG: kernel NULL pointer dereference, address: 00000000000000a8 [ 21.698221] #PF: supervisor read access in kernel mode [ 21.698267] #PF: error_code(0x0000) - not-present page [ 21.698324] PGD 0 P4D 0 [ 21.698353] Oops: 0000 [#1] PREEMPT SMP PTI [ 21.698394] CPU: 0 PID: 326 Comm: segctord Tainted: G U 5.3.11-zen1-1-zen #1 [ 21.698463] Hardware name: LENOVO 20FQCTO1WW/20FQCTO1WW, BIOS N1FET70W (1.44 ) 06/25/2019 [ 21.698536] RIP: 0010:percpu_counter_add_batch+0x26/0xb0 [ 21.698584] Code: 1f 44 00 00 41 56 41 55 49 89 f5 41 54 55 48 89 fd bf 01 00 00 00 53 89 d3 e8 16 d7 b7 ff 48 c7 c7 20 04 d5 9f e8 ba 4e fb ff <48> 8b 45 20 48 63 d3 65 44 8b 30 4d 63 e6 4d 01 ec 4c 39 e2 7e 0a [ 21.698730] RSP: 0018:ffffae868045bc78 EFLAGS: 00010002 [ 21.698777] RAX: 0000000080000002 RBX: 0000000000000018 RCX: 0000000000000001 [ 21.698837] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff9fd50420 [ 21.698897] RBP: 0000000000000088 R08: ffff965f0ad09470 R09: 0000000000000018 [ 21.698956] R10: 0000000000000002 R11: ffff965f217fc000 R12: 0000000000000000 [ 21.699016] R13: 0000000000000001 R14: ffff965f0852f648 R15: ffffe759101f2b00 [ 21.699076] FS: 0000000000000000(0000) GS:ffff965f11400000(0000) knlGS:0000000000000000 [ 21.699143] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 21.699192] CR2: 00000000000000a8 CR3: 000000012d80a002 CR4: 00000000003606f0 [ 21.699252] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 21.699312] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 21.699371] Call Trace: [ 21.699407] __test_set_page_writeback+0x2a4/0x320 [ 21.699471] nilfs_segctor_do_construct+0xd42/0x2640 [nilfs2] [ 21.699529] ? preempt_count_add+0x68/0xa0 [ 21.699570] ? _raw_spin_lock+0x13/0x30 [ 21.699622] nilfs_segctor_construct+0x1f4/0x2f0 [nilfs2] [ 21.699682] nilfs_segctor_thread+0x17b/0x420 [nilfs2] [ 21.699732] ? wait_woken+0x70/0x70 [ 21.699774] kthread+0x131/0x170 [ 21.699817] ? nilfs_transaction_lock+0x250/0x250 [nilfs2] [ 21.699867] ? kthread_park+0x80/0x80 [ 21.699903] ret_from_fork+0x35/0x40 [ 21.699940] Modules linked in: ip_tables x_tables nilfs2 dm_thin_pool dm_persistent_data libcrc32c crc32c_generic dm_bio_prison dm_bufio hid_generic usbhid hid dm_crypt dm_mod crct10dif_pclmul crc32_pclmul crc32c_intel rtsx_pci_sdmmc ghash_clmulni_intel mmc_core serio_raw atkbd libps2 aesni_intel aes_x86_64 crypto_simd cryptd xhci_pci glue_helper xhci_hcd rtsx_pci i8042 serio i915 i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops drm intel_agp intel_gtt agpgart [ 21.700293] CR2: 00000000000000a8 [ 21.700326] ---[ end trace 001ed76babb2cd83 ]--- [ 21.700385] RIP: 0010:percpu_counter_add_batch+0x26/0xb0 [ 21.700433] Code: 1f 44 00 00 41 56 41 55 49 89 f5 41 54 55 48 89 fd bf 01 00 00 00 53 89 d3 e8 16 d7 b7 ff 48 c7 c7 20 04 d5 9f e8 ba 4e fb ff <48> 8b 45 20 48 63 d3 65 44 8b 30 4d 63 e6 4d 01 ec 4c 39 e2 7e 0a [ 21.700578] RSP: 0018:ffffae868045bc78 EFLAGS: 00010002 [ 21.700624] RAX: 0000000080000002 RBX: 0000000000000018 RCX: 0000000000000001 [ 21.700684] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff9fd50420 [ 21.700744] RBP: 0000000000000088 R08: ffff965f0ad09470 R09: 0000000000000018 [ 21.700803] R10: 0000000000000002 R11: ffff965f217fc000 R12: 0000000000000000 [ 21.700862] R13: 0000000000000001 R14: ffff965f0852f648 R15: ffffe759101f2b00 [ 21.700922] FS: 0000000000000000(0000) GS:ffff965f11400000(0000) knlGS:0000000000000000 [ 21.700989] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 21.701039] CR2: 00000000000000a8 CR3: 000000012d80a002 CR4: 00000000003606f0 [ 21.701099] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 21.701158] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 21.701231] note: segctord[326] exited with preempt_count 2 If there is more information I can provide to help troubleshoot, please let me know. Walton
