Hello,

I've seen one weird bug on 5.12.14 that happened a couple of times when I started a bunch of VMs on a server.

I've briefly googled this problem but could not find any relevant commit that would fix this issue.

Do you have any hint how to debug this further or know the fix by any chance?

Thanks in advance. Stack trace following:

[  376.876610] ------------[ cut here ]------------
[  376.881274] kernel BUG at include/linux/swapops.h:204!
[  376.886455] invalid opcode: 0000 [#1] SMP NOPTI
[  376.891014] CPU: 40 PID: 11775 Comm: rpc-worker Tainted: G            E     5.12.14-1.gdc.el8.x86_64 #1
[  376.900464] Hardware name: HPE ProLiant DL380 Gen10/ProLiant DL380 Gen10, BIOS U30 05/24/2021
[  376.909038] RIP: 0010:pmd_migration_entry_wait+0x132/0x140
[  376.914562] Code: 02 00 00 00 5b 4c 89 c7 5d e9 8a e4 f6 ff 48 81 e2 00 f0 ff ff 48 f7 d2 48 21 c2 89 d1 f7 c2 81 01 00 00 75 80 e9 44 ff ff ff <0f> 0b 48 8b 2d 75 bd 30 01 e9 ef fe ff ff 0f 1f 44 00 00 41 55 48
[  376.933443] RSP: 0000:ffffb65a5e1cfdc8 EFLAGS: 00010246
[  376.938701] RAX: 0017ffffc0000000 RBX: ffff908b8ecabaf8 RCX: ffffffffffffffff
[  376.945878] RDX: 0000000000000000 RSI: ffff908b8ecabaf8 RDI: fffff497473b2ae8
[  376.953055] RBP: fffff497473b2ae8 R08: fffff49747fa8080 R09: 0000000000000000
[  376.960230] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000af8
[  376.967407] R13: 0400000000000000 R14: 0400000000000080 R15: ffff908bbef7b6a8
[  376.974582] FS:  00007f5bb1f81700(0000) GS:ffff90e87fd80000(0000) knlGS:0000000000000000
[  376.982718] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  376.988497] CR2: 00007f5b2bfffd98 CR3: 00000001f793e006 CR4: 00000000007726e0
[  376.995673] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  377.002849] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  377.010026] PKRU: 55555554
[  377.012745] Call Trace:
[  377.015207]  __handle_mm_fault+0x5ad/0x6e0
[  377.019335]  handle_mm_fault+0xc5/0x290
[  377.023194]  do_user_addr_fault+0x1cd/0x740
[  377.027406]  exc_page_fault+0x54/0x110
[  377.031182]  ? asm_exc_page_fault+0x8/0x30
[  377.035307]  asm_exc_page_fault+0x1e/0x30
[  377.039340] RIP: 0033:0x7f5bb91d6734
[  377.042937] Code: 89 08 48 8b 35 dd 3b 21 00 4c 8d 0d d6 3b 21 00 31 c0 4c 39 ce 74 73 0f 1f 80 00 00 00 00 48 8d 96 40 fd ff ff 49 39 d2 74 22 <48> 8b 96 d8 03 00 00 48 01 15 4e 7c 21 00 80 be 50 03 00 00 00 c7
[  377.061820] RSP: 002b:00007f5bb1f7ff58 EFLAGS: 00010206
[  377.067076] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f5ba0000020
[  377.074255] RDX: 00007f5b2bfff700 RSI: 00007f5b2bfff9c0 RDI: 0000000000000001
[  377.081429] RBP: 0000000000000001 R08: 0000000000000000 R09: 00007f5bb93ea2f0
[  377.088606] R10: 00007f5bb1f81700 R11: 0000000000000202 R12: 0000000000000001
[  377.095782] R13: 0000000000000006 R14: 0000000000000cb4 R15: 00007f5bb1f801f0
[  377.102958] Modules linked in: ebt_arp(E) nft_meta_bridge(E) ip6_tables(E) xt_CT(E) nf_log_ipv4(E) nf_log_common(E) nft_limit(E) nft_counter(E) xt_LOG(E) xt_limit(E) xt_mac(E) xt_set(E) xt_multiport(E) xt_state(E) xt_conntrack(E) xt_comment(E) xt_physdev(E) nft_compat(E) ip_set_hash_net(E) ip_set(E) vhost_net(E) vhost(E) vhost_iotlb(E) tap(E) tun(E) tcp_diag(E) udp_diag(E) inet_diag(E) netconsole(E) nf_tables(E) vxlan(E) ip6_udp_tunnel(E) udp_tunnel(E) nfnetlink(E) binfmt_misc(E) iscsi_tcp(E) libiscsi_tcp(E) 8021q(E) garp(E) mrp(E) bonding(E) tls(E) vfat(E) fat(E) dm_service_time(E) dm_multipath(E) rpcrdma(E) sunrpc(E) rdma_ucm(E) ib_srpt(E) ib_isert(E) iscsi_target_mod(E) target_core_mod(E) ib_iser(E) rdma_cm(E) iw_cm(E) ib_cm(E) libiscsi(E) scsi_transport_iscsi(E) intel_rapl_msr(E) qedr(E) intel_rapl_common(E) ib_uverbs(E) isst_if_common(E) ib_core(E) nfit(E) libnvdimm(E) x86_pkg_temp_thermal(E) intel_powerclamp(E) coretemp(E) kvm_intel(E) kvm(E) irqbypass(E) crct10dif_pclmul(E)
[  377.102999]  crc32_pclmul(E) ghash_clmulni_intel(E) rapl(E) intel_cstate(E) ipmi_ssif(E) acpi_ipmi(E) ipmi_si(E) mei_me(E) ioatdma(E) ipmi_devintf(E) dm_mod(E) ses(E) intel_uncore(E) pcspkr(E) qede(E) enclosure(E) tg3(E) mei(E) lpc_ich(E) hpilo(E) hpwdt(E) intel_pch_thermal(E) dca(E) ipmi_msghandler(E) acpi_power_meter(E) ext4(E) mbcache(E) jbd2(E) sd_mod(E) t10_pi(E) sg(E) qedf(E) qed(E) crc8(E) libfcoe(E) libfc(E) smartpqi(E) scsi_transport_fc(E) scsi_transport_sas(E) wmi(E) nf_conntrack(E) nf_defrag_ipv6(E) libcrc32c(E) crc32c_intel(E) nf_defrag_ipv4(E) br_netfilter(E) bridge(E) stp(E) llc(E)
[  377.243468] ---[ end trace 04bce3bb051f7620 ]---
[  377.385645] RIP: 0010:pmd_migration_entry_wait+0x132/0x140
[  377.391194] Code: 02 00 00 00 5b 4c 89 c7 5d e9 8a e4 f6 ff 48 81 e2 00 f0 ff ff 48 f7 d2 48 21 c2 89 d1 f7 c2 81 01 00 00 75 80 e9 44 ff ff ff <0f> 0b 48 8b 2d 75 bd 30 01 e9 ef fe ff ff 0f 1f 44 00 00 41 55 48
[  377.410091] RSP: 0000:ffffb65a5e1cfdc8 EFLAGS: 00010246
[  377.415355] RAX: 0017ffffc0000000 RBX: ffff908b8ecabaf8 RCX: ffffffffffffffff
[  377.422540] RDX: 0000000000000000 RSI: ffff908b8ecabaf8 RDI: fffff497473b2ae8
[  377.429721] RBP: fffff497473b2ae8 R08: fffff49747fa8080 R09: 0000000000000000
[  377.436902] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000af8
[  377.444086] R13: 0400000000000000 R14: 0400000000000080 R15: ffff908bbef7b6a8
[  377.451272] FS:  00007f5bb1f81700(0000) GS:ffff90e87fd80000(0000) knlGS:0000000000000000
[  377.459415] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  377.465196] CR2: 00007f5b2bfffd98 CR3: 00000001f793e006 CR4: 00000000007726e0
[  377.472377] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  377.479556] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  377.486738] PKRU: 55555554
[  377.489465] Kernel panic - not syncing: Fatal exception
[  377.573911] Kernel Offset: 0xa000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
[  377.716482] ---[ end Kernel panic - not syncing: Fatal exception ]---