https://bugzilla.kernel.org/show_bug.cgi?id=220453 Bug ID: 220453 Summary: kvm/arm64: nv - guest with hypervisor hangs Product: Virtualization Version: unspecified Hardware: ARM OS: Linux Status: NEW Severity: normal Priority: P3 Component: kvm Assignee: virtualization_kvm@xxxxxxxxxxxxxxxxxxxx Reporter: amy.fong.3142@xxxxxxxxx Regression: No On a kernel with nested virtualization (seen in 6.16 and 6.17rc1) on a neoverse-v2 system, attempts to create a guest with virtualization capabilities fails. The guest hangs and a kernel bug dump is seen. The defect is not seen when the nested virt system is booted from qemu using neoverse-v1 * fails: lkvm run ... --nested * passes: lkvm run ... --nested --e2h0 Using git bisect, the following commit (b5fa1f91e11fdf74ad4e2ac6dae246a57cbd2d95) results in the defect, reverting the patch removes the issue. commit b5fa1f91e11fdf74ad4e2ac6dae246a57cbd2d95 Author: Marc Zyngier <maz@xxxxxxxxxx> Date: Tue Jun 3 08:08:24 2025 +0100 KVM: arm64: Make __vcpu_sys_reg() a pure rvalue operand Kernel bug dump: Aug 15 01:47:28 graviton-d kernel: ------------[ cut here ]------------ Aug 15 01:47:28 graviton-d kernel: WARNING: CPU: 1 PID: 178543 at ./arch/arm64/include/asm/kvm_emulate.h:595 perform_access+0x d4/0xe0 Aug 15 01:47:28 graviton-d kernel: Modules linked in: snd_seq_dummy snd_hrtimer snd_seq snd_seq_device snd_timer snd soundcore xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT nf_reject_ipv4 xt_tcpudp nft_compat x_tables nft_chain_nat nf_nat nf_conntr ack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables nfnetlink bridge stp llc vgem drm_shmem_helper drm_kms_helper binfmt_misc nls_asci i nls_cp437 vfat fat rpcsec_gss_krb5 aes_ce_blk aes_ce_cipher polyval_ce ghash_ce gf128mul sha3_ce sha3_generic arm_smmuv3_pmu arm_spe_pmu arm_cmn evdev nfsv4 nfsd dns_resolver nfs auth_rpcgss nfs_acl lockd drm grace dm_mod sunrpc ecryptfs loop dax drm _panel_orientation_quirks configfs efivarfs autofs4 Aug 15 01:47:28 graviton-d kernel: CPU: 1 UID: 0 PID: 178543 Comm: kvm-vcpu-0 Not tainted 6.17.0-rc1-dirty #29 VOLUNTARY Aug 15 01:47:28 graviton-d kernel: Hardware name: Amazon EC2 r8g.metal-24xl/Not Specified, BIOS 1.0 10/16/2017 Aug 15 01:47:28 graviton-d kernel: pstate: 02400009 (nzcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--) Aug 15 01:47:28 graviton-d kernel: pc : perform_access+0xd4/0xe0 Aug 15 01:47:28 graviton-d kernel: lr : perform_access+0x4c/0xe0 Aug 15 01:47:28 graviton-d kernel: sp : ffff8000c31af850 Aug 15 01:47:28 graviton-d kernel: x29: ffff8000c31af850 x28: ffff0003d8886d80 x27: 0000000000000000 Aug 15 01:47:28 graviton-d kernel: x26: 0000000000000000 x25: ffff00007780c4e0 x24: 0000000000000000 Aug 15 01:47:28 graviton-d kernel: x23: ffff00007780c528 x22: 0000000000000000 x21: ffff8000c31af890 Aug 15 01:47:28 graviton-d kernel: x20: ffffb5accbdc0da0 x19: ffff00007780c4e0 x18: ffff8000c31af180 Aug 15 01:47:28 graviton-d kernel: x17: 000000040044ffff x16: 00100075f5507510 x15: 0000000000000000 Aug 15 01:47:28 graviton-d kernel: x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000001388 Aug 15 01:47:28 graviton-d kernel: x11: 00000000000013f0 x10: 00000000000014c0 x9 : ffffb5accac9e2f0 Aug 15 01:47:28 graviton-d kernel: x8 : ffff8000c31af8d8 x7 : 0000000000000000 x6 : 0000000000000004 Aug 15 01:47:28 graviton-d kernel: x5 : 000000000000000f x4 : ffffb5accac9e3dc x3 : ffff0003d8886d80 Aug 15 01:47:28 graviton-d kernel: x2 : ffffb5accaca1510 x1 : 0000000000000000 x0 : 0000000000000009 Aug 15 01:47:28 graviton-d kernel: Call trace: Aug 15 01:47:28 graviton-d kernel: perform_access+0xd4/0xe0 (P) Aug 15 01:47:28 graviton-d kernel: kvm_handle_sys_reg+0xfc/0x1a0 Aug 15 01:47:28 graviton-d kernel: handle_exit+0x68/0x168 Aug 15 01:47:28 graviton-d kernel: kvm_arch_vcpu_ioctl_run+0x2cc/0x908 Aug 15 01:47:28 graviton-d kernel: kvm_vcpu_ioctl+0x1a8/0xb20 Aug 15 01:47:28 graviton-d kernel: __arm64_sys_ioctl+0xb4/0x118 Aug 15 01:47:28 graviton-d kernel: invoke_syscall+0x70/0x100 Aug 15 01:47:28 graviton-d kernel: el0_svc_common.constprop.0+0xc8/0xf0 Aug 15 01:47:28 graviton-d kernel: do_el0_svc+0x24/0x38 Aug 15 01:47:28 graviton-d kernel: el0_svc+0x34/0xf0 Aug 15 01:47:28 graviton-d kernel: el0t_64_sync_handler+0xa0/0xe8 Aug 15 01:47:28 graviton-d kernel: el0t_64_sync+0x198/0x1a0 Aug 15 01:47:28 graviton-d kernel: ---[ end trace 0000000000000000 ]--- -- You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.
