Still happens with the new v5.17.11 kernel package, in fact it may have gotten worse because at one point the box crashed shortly after starting a guest VM:
[ 2256.562873] BUG: kernel NULL pointer dereference, address: 000000000000000b [ 2256.585773] #PF: supervisor write access in kernel mode [ 2256.602946] #PF: error_code(0x0002) - not-present page [ 2256.619832] PGD 0 P4D 0 [ 2256.628138] Oops: 0002 [#1] PREEMPT SMP PTI [ 2256.641880] CPU: 15 PID: 3258 Comm: qemu-system-x86 Kdump: loaded Not tainted 5.17.0-3-amd64 #1 Debian 5.17.11-1 [ 2256.675643] Hardware name: Intel Corporation T5520UR/T5520UR, BIOS S5500.86B.01.00.0061.030920121535 03/09/2012 [ 2256.708831] RIP: 0010:kvm_replace_memslot+0xcf/0x390 [kvm] [ 2256.726925] Code: 44 24 08 48 85 db 0f 84 3b 02 00 00 48 89 ea 48 c1 e2 04 48 01 da 48 8b 4a 08 48 85 c9 74 1e 48 8b 32 48 89 31 48 85 f6 74 04 <48> 89 4e 08 48 c7 02 00 00 00 00 48 c7 42 08 00 00 00 00 48 8d 54 [ 2256.788713] RSP: 0018:ffffb8dd467dfd70 EFLAGS: 00010206 [ 2256.805885] RAX: ffffb8dd468518b8 RBX: ffff8b57b7598e00 RCX: ffffb8dd46851af8 [ 2256.829350] RDX: ffff8b57b7598e00 RSI: 0000000000000003 RDI: ffffb8dd46851000 [ 2256.852815] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000860 [ 2256.876279] R10: 000000000000000b R11: 0000000000000004 R12: 0000000000000000 [ 2256.899744] R13: 0000000000000000 R14: 0000000000000001 R15: ffffb8dd46851000 [ 2256.923207] FS: 00007f85ddf10640(0000) GS:ffff8b5d97bc0000(0000) knlGS:0000000000000000 [ 2256.949816] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2256.968704] CR2: 000000000000000b CR3: 0000000675c84004 CR4: 00000000000226e0 [ 2256.992168] Call Trace: [ 2257.000193] <TASK> [ 2257.007071] ? _raw_read_unlock+0x18/0x30 [ 2257.020245] kvm_set_memslot+0x3c2/0x4a0 [kvm] [ 2257.034888] kvm_vm_ioctl+0x2cb/0xd80 [kvm] [ 2257.048674] ? handle_mm_fault+0xb2/0x280 [ 2257.061848] __x64_sys_ioctl+0x82/0xb0 [ 2257.074164] do_syscall_64+0x3b/0xc0 [ 2257.085908] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 2257.102511] RIP: 0033:0x7f85e12c0397 [ 2257.114249] Code: 3c 1c e8 1c ff ff ff 85 c0 79 87 49 c7 c4 ff ff ff ff 5b 5d 4c 89 e0 41 5c c3 66 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a9 da 0d 00 f7 d8 64 89 01 48 [ 2257.176038] RSP: 002b:00007f85ddf0eea8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 2257.200933] RAX: ffffffffffffffda RBX: 000000004020ae46 RCX: 00007f85e12c0397 [ 2257.224398] RDX: 00007f85ddf0ef70 RSI: 000000004020ae46 RDI: 000000000000000c [ 2257.247861] RBP: 00005643173201f0 R08: 0000000000000007 R09: 00007f85d40e9ad0 [ 2257.271326] R10: 00000000fd000000 R11: 0000000000000246 R12: 00007f85ddf0ef70 [ 2257.294791] R13: 0000000001000000 R14: 0000564317dac470 R15: 00000000fd000000 [ 2257.318258] </TASK> [ 2257.325420] Modules linked in: nf_conntrack_netlink xfrm_user xfrm_algo br_netfilter bridge stp llc overlay autofs4 ip6_tables ip6t_rpfilter nft_chain_nat xt_MASQUERADE nf_nat xt_addrtype ip_tables xt_conntrack ipt_REJECT nf_reject_ipv4 nf_conntrack_tftp nf_conntrack_ftp xt_tcpudp ipt_rpfilter xt_CT nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nft_compat nf_tables x_tables nfnetlink nfsd auth_rpcgss nfs_acl nfs lockd grace fscache netfs sunrpc jc42 vhost_vsock vmw_vsock_virtio_transport_common vsock vhost_net tun vhost vhost_iotlb tap ipmi_watchdog nbd squashfs loop dm_crypt dm_mod intel_powerclamp coretemp kvm_intel ipmi_ssif kvm irqbypass mgag200 ghash_clmulni_intel drm_shmem_helper drm_kms_helper aesni_intel cec crypto_simd acpi_ipmi cryptd rc_core ipmi_si intel_cstate iTCO_wdt intel_pmc_bxt iTCO_vendor_support ipmi_devintf drm evdev intel_uncore watchdog sg ipmi_msghandler ioatdma i5500_temp i7core_edac button acpi_cpufreq xfs libcrc32c crc32c_generic uas hid_generic sd_mod ses t10_pi [ 2257.325496] usbhid enclosure usb_storage crc_t10dif hid scsi_transport_sas crct10dif_generic ata_generic uhci_hcd ehci_pci megaraid_sas igb ata_piix ehci_hcd libata i2c_algo_bit dca crct10dif_pclmul crct10dif_common scsi_mod ptp i2c_i801 crc32_pclmul usbcore crc32c_intel i2c_smbus lpc_ich scsi_common usb_common pps_core [ 2257.706780] CR2: 000000000000000b -- Jon Doge Wrangler X(7): A program for managing terminal windows. See also screen(1) and tmux(1).
