This line, if (WARN_ON_ONCE(fc != 0x03)) qemu-kvm-2.12.0-99.module+el8.2.0+5827+8c39933c with this kernel config, https://raw.githubusercontent.com/cailca/linux-mm/master/s390.config # /usr/libexec/qemu-kvm -name ubuntu-18.04-server-cloudimg -cpu host -smp 2 -m 2G -hda ubuntu-18.04-server-cloudimg.qcow2 -cdrom ubuntu-18.04-server-cloudimg.iso -nic user,hostfwd=tcp::2222-:22 -nographic 00: [ 424.578896] WARNING: CPU: 0 PID: 1533 at arch/s390/kvm/priv.c:632 handle_ 00: pqap+0x2b6/0x468 [kvm] 00: [ 424.578934] Modules linked in: kvm ip_tables x_tables xfs dasd_fba_mod da 00: sd_eckd_mod dm_mirror dm_region_hash dm_log dm_mod 00: [ 424.579026] CPU: 0 PID: 1533 Comm: qemu-kvm Not tainted 5.7.0-rc3-next-20 00: 200501 #2 00: [ 424.579064] Hardware name: IBM 2964 N96 400 (z/VM 6.4.0) 00: [ 424.579101] Krnl PSW : 0704d00180000000 000003ff80440dc2 (handle_pqap+0x2 00: ba/0x468 [kvm]) 00: [ 424.579239] R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 00: RI:0 EA:3 00: [ 424.579282] Krnl GPRS: 0000000000000000 0000030000000000 0000030000000000 00: 00000000e1ca6148 00: [ 424.579320] 0000030000000000 000003ff80440c14 0000000000000000 00: 00000000822e8520 00: [ 424.579359] 00000000e1ca6000 000000009c79a000 00000000822e8008 00: 0000007c00877e70 00: [ 424.579399] 000003ff803f5000 000003ff80467528 000003ff80440c14 00: 000003e0043bf2c8 00: [ 424.579461] Krnl Code: 000003ff80440db6: a774ff5a brc 7,00 00: 0003ff80440c6a 00: [ 424.579461] 000003ff80440dba: a7f4ff54 brc 15,0 00: 00003ff80440c62 00: [ 424.579461] #000003ff80440dbe: af000000 mc 0,0 00: [ 424.579461] >000003ff80440dc2: a798ffa1 lhi %r9, 00: -95 00: [ 424.579461] 000003ff80440dc6: a51d0300 llihl %r1, 00: 768 00: [ 424.579461] 000003ff80440dca: b90800b1 agr %r11 00: ,%r1 00: [ 424.579461] 000003ff80440dce: d70bb000b000 xc 0(12 00: ,%r11),0(%r11) 00: [ 424.579461] 000003ff80440dd4: b9140029 lgfr %r2, 00: %r9 00: [ 424.586765] Call Trace: 00: [ 424.586894] [<000003ff80440dc2>] handle_pqap+0x2ba/0x468 [kvm] 00: [ 424.587026] [<000003ff80446fa6>] kvm_s390_handle_b2+0x2f6/0x950 [kvm] 00: [ 424.587156] [<000003ff8042d74c>] kvm_handle_sie_intercept+0x154/0x1db0 [ 00: kvm] 00: [ 424.587287] [<000003ff80426950>] __vcpu_run+0x1040/0x2150 [kvm] 00: [ 424.587414] [<000003ff8042941a>] kvm_arch_vcpu_ioctl_run+0x5fa/0x1338 [k 00: vm] 00: [ 424.587540] [<000003ff8040195e>] kvm_vcpu_ioctl+0x346/0xa10 [kvm] 00: [ 424.587590] [<00000001433fbd16>] ksys_ioctl+0x276/0xbb8 00: [ 424.587630] [<00000001433fc682>] __s390x_sys_ioctl+0x2a/0x38 00: [ 424.587674] [<000000014393c880>] system_call+0xd8/0x2b4 00: [ 424.587715] 2 locks held by qemu-kvm/1533: 00: [ 424.587748] #0: 00000000822e80d0 (&vcpu->mutex){+.+.}-{3:3}, at: kvm_vcp 00: u_ioctl+0x170/0xa10 [kvm] 00: [ 424.587898] #1: 0000000081fe3980 (&kvm->srcu){....}-{0:0}, at: __vcpu_ru 00: n+0x60a/0x2150 [kvm] 00: [ 424.588045] Last Breaking-Event-Address: 00: [ 424.588169] [<000003ff80440c1e>] handle_pqap+0x116/0x468 [kvm] 00: [ 424.588204] irq event stamp: 23141 00: [ 424.588246] hardirqs last enabled at (23149): [<000000014308f3de>] conso 00: le_unlock+0x766/0xa20 00: [ 424.588287] hardirqs last disabled at (23156): [<000000014308ee40>] conso 00: le_unlock+0x1c8/0xa20 00: [ 424.588536] softirqs last enabled at (22998): [<000000014393e162>] __do_ 00: softirq+0x6e2/0xa48 00: [ 424.588583] softirqs last disabled at (22983): [<0000000142f652dc>] do_so 00: ftirq_own_stack+0xe4/0x100 00: [ 424.588625] ---[ end trace e420441aa7c001ac ]---