[RHEL7.4 and 7.5 for PPC LE]Kernel panics with oops message at tg_prfill_cpu_rwstat+0x98/0x150

Issue

• Kernel panics with following message:

[48319.513152] Unable to handle kernel paging request for data at address 0x00950020
[48319.513200] Faulting instruction address: 0xc0000000004f6928
[48319.513218] Oops: Kernel access of bad area, sig: 11 [#1]
[48319.513235] SMP NR_CPUS=2048 NUMA pSeries
[48319.513248] Modules linked in: vfat fat tcp_diag udp_diag inet_diag unix_diag af_packet_diag netlink_diag veth xt_statistic xt_nat xt_recent xt_ipvs ip_vs xt_set ip_set_hash_ip ip_set_hash_net xt_comment ipt_MASQUERADE nf_nat_masquerade_ipv4 nf_conntrack_netlink br_netfilter nfsv3 nfs_acl dm_thin_pool dm_persistent_data dm_bio_prison dm_bufio loop rpcsec_gss_krb5 nfsv4 dns_resolver nfs lockd grace fscache ip6t_rpfilter ipt_REJECT nf_reject_ipv4 ip6t_REJECT nf_reject_ipv6 xt_conntrack ebtable_nat ebtable_broute bridge stp llc ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw ebtable_filter ebtables ip6table_filter iptable_filter
[48319.513415]  sg pseries_rng ipip tunnel4 ip_tunnel xt_multiport xt_addrtype xt_mark ip_set nfnetlink ip6_tables auth_rpcgss sunrpc ip_tables xfs libcrc32c dm_service_time sd_mod sr_mod crc_t10dif cdrom crct10dif_generic crct10dif_common ibmvfc ibmvscsi scsi_transport_fc scsi_transport_srp dm_multipath ibmveth scsi_tgt dm_mirror dm_region_hash dm_log dm_mod
[48319.513502] CPU: 6 PID: 3459 Comm: hyperkube Kdump: loaded Not tainted 3.10.0-862.6.3.el7.ppc64le #1
[48319.513512] task: c000000396b30180 ti: c000000396508000 task.ti: c000000396508000
[48319.513521] NIP: c0000000004f6928 LR: c0000000004f698c CTR: c0000000004f6890
[48319.513531] REGS: c00000039650b900 TRAP: 0300   Not tainted  (3.10.0-862.6.3.el7.ppc64le)
[48319.513539] MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE>  CR: 42402444  XER: 20000000
[48319.513576] CFAR: c0000000000093ec DAR: 0000000000950020 DSISR: 40000000 SOFTE: 0 
               GPR00: c0000000004f3778 c00000039650bb80 c000000001274800 0000000000000000 
               GPR04: 0000000000000000 0000000000000000 0000000000000000 c0000000012c0ae0 
               GPR08: 0000000000950000 0000000000000000 0000000000950020 0000000000000000 
               GPR12: c0000000004f6890 c000000007b33600 0000000000000001 000000c41ffa6660 
               GPR16: 0000000000000000 0000000000000000 000000c422b97000 c0000003acf55f78 
               GPR20: 0000000000001000 c00000039650bdf0 c000000053553800 0000000000000000 
               GPR24: 0000000000000001 0000000000000000 0000000000000000 c0000003acf55f40 
               GPR28: c0000000012c4d20 c0000000012c6094 c0000000b8227c00 0000000000000020 
[48319.513717] NIP [c0000000004f6928] tg_prfill_cpu_rwstat+0x98/0x150
[48319.513726] LR [c0000000004f698c] tg_prfill_cpu_rwstat+0xfc/0x150
[48319.513732] Call Trace:
[48319.513740] [c00000039650bb80] [c0000000002aeb30] do_wp_page+0x250/0x890 (unreliable)
[48319.513752] [c00000039650bc30] [c0000000004f3778] blkcg_print_blkgs+0xd8/0x1f0
[48319.513765] [c00000039650bce0] [c0000000004f67ac] tg_print_cpu_rwstat+0x3c/0x60
[48319.513778] [c00000039650bd00] [c0000000001a5da8] cgroup_seqfile_show+0x88/0xa0
[48319.513791] [c00000039650bd30] [c00000000037c4a8] seq_read+0x138/0x580
[48319.513805] [c00000039650bdd0] [c000000000337310] SyS_read+0x140/0x3b0
[48319.513821] [c00000039650be30] [c00000000000a284] system_call+0x38/0xfc
[48319.513829] Instruction dump:
[48319.513836] 60000000 60420000 3ce20005 38e7c2e0 e95e01e0 e9610060 e8610068 e8810070 
[48319.513865] e8a10078 7d07402a 7d0a4214 7d48fa14 <7cc8f82a> e8ea0008 e90a0010 e94a0018 
[48319.513896] ---[ end trace 491d8e94882265ae ]---
[48319.527494] 
[48319.527510] Sending IPI to other CPUs
[48319.528516] IPI complete