[bug] KVM: Unrecoverable TM Unavailable Exception f60

[Jan Stancek <jstancek@redhat.com>]

Hi,

I'm running into Oops below on IBM PowerNV system (model 8247-22L)
with 4.12 trees and qemu-kvm-2.9. It triggers quickly after I start
KVM guest installation:

virt-install  --name ppc64le_kvm_1cpu --mac 52:56:00:00:00:06 --location nfs://XXX --ram=1024 --vcpus=1 --file-size=20 --hvm --nonsparse --debug --nographics --noautoconsole --wait -1 --prompt --accelerate --os-variant=virtio26 --network bridge:br3,model=virtio --serial pty --console pty --file /home/virtimages/VirtualMachines/ppc64le_kvm_1cpu.img --extra-args "serial console=tty0 console=hvc0" --noreboot

# git describe
v4.12-10985-g4ca6df1

# cat /proc/cpuinfo | head
processor	: 0
cpu		: POWER8E (raw), altivec supported
clock		: 3325.000000MHz
revision	: 2.1 (pvr 004b 0201)

4.11 works OK
4.11 with these 4 patches applied panics in same way as latest HEAD (v4.12-10985-g4ca6df1)
  KVM: PPC: Book3S HV: Save/restore host values of debug registers
  KVM: PPC: Book3S HV: Preserve userspace HTM state properly
  KVM: PPC: Book3S HV: Restore critical SPRs to host values on guest exit
  KVM: PPC: Book3S HV: Context-switch EBB registers properly

---

[  181.328511] Unrecoverable TM Unavailable Exception f60 at d00000001e7d9980
[  181.328605] Oops: Unrecoverable TM Unavailable Exception, sig: 6 [#1]
[  181.328613] SMP NR_CPUS=2048 
[  181.328613] NUMA 
[  181.328618] PowerNV
[  181.328646] Modules linked in: vhost_net vhost tap nfs_layout_nfsv41_files rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack ipt_REJECT nf_reject_ipv4 tun ebtable_filter ebtables ip6table_filter ip6_tables iptable_filter bridge stp llc kvm_hv kvm nfsd ses enclosure scsi_transport_sas ghash_generic auth_rpcgss gf128mul xts sg ctr nfs_acl lockd vmx_crypto shpchp ipmi_powernv i2c_opal grace ipmi_devintf i2c_core powernv_rng sunrpc ipmi_msghandler ibmpowernv uio_pdrv_genirq uio leds_powernv powernv_op_panel ip_tables xfs sd_mod lpfc ipr bnx2x libata mdio ptp pps_core scsi_transport_fc libcrc32c dm_mirror dm_region_hash dm_log dm_mod
[  181.329278] CPU: 40 PID: 9926 Comm: CPU 0/KVM Not tainted 4.12.0+ #1
[  181.329337] task: c000003fc6980000 task.stack: c000003fe4d80000
[  181.329396] NIP: d00000001e7d9980 LR: d00000001e77381c CTR: d00000001e7d98f0
[  181.329465] REGS: c000003fe4d837e0 TRAP: 0f60   Not tainted  (4.12.0+)
[  181.329523] MSR: 9000000000009033 <SF,HV,EE,ME,IR,DR,RI,LE>
[  181.329527]   CR: 24022448  XER: 00000000
[  181.329608] CFAR: d00000001e773818 SOFTE: 1 
[  181.329608] GPR00: d00000001e77381c c000003fe4d83a60 d00000001e7ef410 c000003fdcfe0000 
[  181.329608] GPR04: c000003fe4f00000 0000000000000000 0000000000000000 c000003fd7954800 
[  181.329608] GPR08: 0000000000000001 c000003fc6980000 0000000000000000 d00000001e7e2880 
[  181.329608] GPR12: d00000001e7d98f0 c000000007b19000 00000001295220e0 00007fffc0ce2090 
[  181.329608] GPR16: 0000010011886608 00007fff8c89f260 0000000000000001 00007fff8c080028 
[  181.329608] GPR20: 0000000000000000 00000100118500a6 0000010011850000 0000010011850000 
[  181.329608] GPR24: 00007fffc0ce1b48 0000010011850000 00000000d673b901 0000000000000000 
[  181.329608] GPR28: 0000000000000000 c000003fdcfe0000 c000003fdcfe0000 c000003fe4f00000 
[  181.330199] NIP [d00000001e7d9980] kvmppc_vcpu_run_hv+0x90/0x6b0 [kvm_hv]
[  181.330264] LR [d00000001e77381c] kvmppc_vcpu_run+0x2c/0x40 [kvm]
[  181.330322] Call Trace:
[  181.330351] [c000003fe4d83a60] [d00000001e773478] kvmppc_set_one_reg+0x48/0x340 [kvm] (unreliable)
[  181.330437] [c000003fe4d83b30] [d00000001e77381c] kvmppc_vcpu_run+0x2c/0x40 [kvm]
[  181.330513] [c000003fe4d83b50] [d00000001e7700b4] kvm_arch_vcpu_ioctl_run+0x114/0x2a0 [kvm]
[  181.330586] [c000003fe4d83bd0] [d00000001e7642f8] kvm_vcpu_ioctl+0x598/0x7a0 [kvm]
[  181.330658] [c000003fe4d83d40] [c0000000003451b8] do_vfs_ioctl+0xc8/0x8b0
[  181.330717] [c000003fe4d83de0] [c000000000345a64] SyS_ioctl+0xc4/0x120
[  181.330776] [c000003fe4d83e30] [c00000000000b004] system_call+0x58/0x6c
[  181.330833] Instruction dump:
[  181.330869] e92d0260 e9290b50 e9290108 792807e3 41820058 e92d0260 e9290b50 e9290108 
[  181.330941] 792ae8a4 794a1f87 408204f4 e92d0260 <7d4022a6> f9490ff0 e92d0260 7d4122a6 
[  181.331013] ---[ end trace 6f6ddeb4bfe92a92 ]---
[  181.334574] 
[  183.334758] Kernel panic - not syncing: Fatal exception
[  183.338352] Rebooting in 10 seconds..

---

Regards,
Jan