RHEL8: Kernel panic at process_one_work+0x2e with cifs

Issue

• Kernel panic with log:

[3395043.961944] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
[3395043.961948] CIFS: VFS: \\1.2.3.4 has not responded in 180 seconds. Reconnecting...
[3395043.961949] PGD 0 
[3395043.961949] CIFS: VFS: \\2.3.4.5 has not responded in 180 seconds. Reconnecting...
[3395043.961965] P4D 0 
[3395043.961969] Oops: 0000 [#1] SMP NOPTI
[3395043.961972] CPU: 1 PID: 794907 Comm: kworker/1:9 Not tainted 4.18.0-477.27.1.el8_8.x86_64 #1
[3395043.961975] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020
[3395043.961980] Workqueue:  0x0 (cifsiod)
[3395043.961984] RIP: 0010:process_one_work+0x2e/0x360
[3395043.961992] Code: 00 41 57 41 56 41 55 41 54 55 53 48 89 f3 48 83 ec 08 48 8b 06 48 8b 6f 40 49 89 c4 45 30 e4 a8 04 b8 00 00 00 00 4c 0f 44 e0 <49> 8b 44 24 08 44 8b a8 00 01 00 00 41 83 e5 20 f6 45 10 04 75 0e
[3395043.962005] RSP: 0018:ffffa44b86293ea0 EFLAGS: 00010046
[3395043.962007] RAX: 0000000000000000 RBX: ffff8938d3f23f00 RCX: ffffc44b7f844c60
[3395043.962010] RDX: ffffc44b7f844c60 RSI: ffff8938d3f23f00 RDI: ffff89412d7b2480
[3395043.962012] RBP: ffff89577fc72840 R08: ffff89577fc40000 R09: ffffffffc09dd200
[3395043.962013] R10: ffffa44b86293e78 R11: 0000000000000001 R12: 0000000000000000
[3395043.962016] R13: ffff89577fc72860 R14: ffff89577fc72910 R15: ffff89412d7b2480
[3395043.962018] FS:  0000000000000000(0000) GS:ffff89577fc40000(0000) knlGS:0000000000000000
[3395043.962020] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[3395043.962022] CR2: 00000000000000b0 CR3: 0000000f8a010004 CR4: 00000000007706e0
[3395043.962032] CIFS: VFS: \\TORS10.ddnet1.net has not responded in 180 seconds. Reconnecting...
[3395043.962060] PKRU: 55555554
[3395043.962062] Call Trace:
[3395043.962097]  worker_thread+0x1f9/0x390
[3395043.962101]  ? create_worker+0x1a0/0x1a0
[3395043.962104]  kthread+0x134/0x150
[3395043.962108]  ? set_kthread_struct+0x50/0x50
[3395043.962127]  ret_from_fork+0x1f/0x40
[3395043.962133] Modules linked in: nfsd xt_CHECKSUM ipt_MASQUERADE xt_conntrack ipt_REJECT nf_reject_ipv4 nft_compat nft_counter nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables libcrc32c nfnetlink bridge stp llc rpcsec_gss_krb5 auth_rpcgss nfsv3 nfs_acl nfsv4 md4 cmac nls_utf8 nfs lockd grace cifs fscache rdma_cm iw_cm ib_cm ib_core libarc4 dns_resolver cfg80211 rfkill vsock_loopback vmw_vsock_virtio_transport_common vmw_vsock_vmci_transport vsock sunrpc intel_rapl_msr intel_rapl_common intel_uncore_frequency_common isst_if_mbox_msr isst_if_common nfit libnvdimm vmw_balloon crct10dif_pclmul crc32_pclmul ghash_clmulni_intel rapl joydev pcspkr vmw_vmci i2c_piix4 binfmt_misc ext4 mbcache jbd2 sr_mod cdrom sd_mod t10_pi sg ata_generic vmwgfx drm_ttm_helper ttm drm_kms_helper crc32c_intel syscopyarea sysfillrect sysimgblt fb_sys_fops drm ahci serio_raw ata_piix libahci libata vmxnet3 vmw_pvscsi dm_mod fuse
[3395043.962220] CR2: 0000000000000008
[3395043.962228] ---[ end trace dfea9ec858c34ce0 ]---
[3395043.962230] RIP: 0010:process_one_work+0x2e/0x360
[3395043.962233] Code: 00 41 57 41 56 41 55 41 54 55 53 48 89 f3 48 83 ec 08 48 8b 06 48 8b 6f 40 49 89 c4 45 30 e4 a8 04 b8 00 00 00 00 4c 0f 44 e0 <49> 8b 44 24 08 44 8b a8 00 01 00 00 41 83 e5 20 f6 45 10 04 75 0e
[3395043.962236] RSP: 0018:ffffa44b86293ea0 EFLAGS: 00010046
[3395043.962239] RAX: 0000000000000000 RBX: ffff8938d3f23f00 RCX: ffffc44b7f844c60
[3395043.962241] RDX: ffffc44b7f844c60 RSI: ffff8938d3f23f00 RDI: ffff89412d7b2480
[3395043.962243] RBP: ffff89577fc72840 R08: ffff89577fc40000 R09: ffffffffc09dd200
[3395043.962244] R10: ffffa44b86293e78 R11: 0000000000000001 R12: 0000000000000000
[3395043.962246] R13: ffff89577fc72860 R14: ffff89577fc72910 R15: ffff89412d7b2480
[3395043.962248] FS:  0000000000000000(0000) GS:ffff89577fc40000(0000) knlGS:0000000000000000
[3395043.962250] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[3395043.962252] CR2: 00000000000000b0 CR3: 0000000f8a010004 CR4: 00000000007706e0
[3395043.962291] PKRU: 55555554
[3395043.962293] Kernel panic - not syncing: Fatal exception
[3395043.962343] Kernel Offset: 0x27400000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
[3395043.962346] ---[ end Kernel panic - not syncing: Fatal exception ]---