[6.6-rc3] WARNING at arch/powerpc/mm/book3s64/radix_tlb.c:1221

[Sachin Sant]

While running kernel selftests (powerpc/mce) following warning is triggered

TAP version 13
1..1
# timeout set to 45
# selftests: powerpc/mce: inject-ra-err
[   37.851967] Disabling lock debugging due to kernel taint
[   37.851977] MCE: CPU19: machine check (Severe)  Real address Load/Store (foreign/control memory) [Not recovered]
[   37.851982] MCE: CPU19: PID: 5254 Comm: inject-ra-err NIP: [0000000010000e48]
[   37.851986] MCE: CPU19: Initiator CPU
[   37.851988] MCE: CPU19: Unknown
[   37.852082] ------------[ cut here ]------------
[   37.852086] WARNING: CPU: 19 PID: 5254 at arch/powerpc/mm/book3s64/radix_tlb.c:1221 radix__tlb_flush+0x160/0x180
[   37.852096] Modules linked in: rpadlpar_io(E) rpaphp(E) xsk_diag(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) bonding(E) tls(E) rfkill(E) ip_set(E) nf_tables(E) nfnetlink(E) sunrpc(E) binfmt_misc(E) pseries_rng(E) aes_gcm_p10_crypto(E) drm(E) drm_panel_orientation_quirks(E) xfs(E) libcrc32c(E) sd_mod(E) sr_mod(E) t10_pi(E) crc64_rocksoft_generic(E) cdrom(E) crc64_rocksoft(E) crc64(E) sg(E) ibmvscsi(E) scsi_transport_srp(E) ibmveth(E) vmx_crypto(E) fuse(E)
[   37.852146] CPU: 19 PID: 5254 Comm: inject-ra-err Kdump: loaded Tainted: G   M        E      6.6.0-rc3-00055-g9ed22ae6be81 #4
[   37.852153] Hardware name: IBM,9080-HEX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1030.20 (NH1030_058) hv:phyp pSeries
[   37.852157] NIP:  c0000000000a9c30 LR: c0000000000a9bd4 CTR: c00000000010a2d0
[   37.852161] REGS: c000000227b8b860 TRAP: 0700   Tainted: G   M        E       (6.6.0-rc3-00055-g9ed22ae6be81)
[   37.852166] MSR:  8000000000029033 <SF,EE,ME,IR,DR,RI,LE>  CR: 44002222  XER: 20040000
[   37.852177] CFAR: c0000000000a9bdc IRQMASK: 0
[   37.852177] GPR00: c0000000000a9bc4 c000000227b8bb00 c000000001902000 0000000000000041
[   37.852177] GPR04: 0000000000000002 0000000000000080 0000000000000000 0000000000000080
[   37.852177] GPR08: 0000000000000002 0000000000000001 c000000e81c73e90 0000000044002228
[   37.852177] GPR12: c00000000010a2d0 c000000e87bf6b00 0000000000000000 0000000000000000
[   37.852177] GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
[   37.852177] GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
[   37.852177] GPR24: 0000000000000000 0000000000000001 0000000000000000 c000000005533b00
[   37.852177] GPR28: c000000005533b60 0000000000000000 c000000227b8bbc0 c000000005533a80
[   37.852222] NIP [c0000000000a9c30] radix__tlb_flush+0x160/0x180
[   37.852227] LR [c0000000000a9bd4] radix__tlb_flush+0x104/0x180
[   37.852232] Call Trace:
[   37.852235] [c000000227b8bb00] [c0000000000a9bc4] radix__tlb_flush+0xf4/0x180 (unreliable)
[   37.852241] [c000000227b8bb30] [c0000000004e5dfc] tlb_finish_mmu+0x15c/0x1e0
[   37.852250] [c000000227b8bb60] [c0000000004e1840] exit_mmap+0x1a0/0x510
[   37.852256] [c000000227b8bc90] [c000000000158760] __mmput+0x60/0x1e0
[   37.852262] [c000000227b8bcc0] [c000000000168b0c] exit_mm+0xdc/0x170
[   37.852269] [c000000227b8bd00] [c000000000168e5c] do_exit+0x2bc/0x5a0
[   37.852280] [c000000227b8bdb0] [c00000000016938c] do_group_exit+0x4c/0xc0
[   37.852286] [c000000227b8bdf0] [c000000000169428] sys_exit_group+0x28/0x30
[   37.852291] [c000000227b8be10] [c000000000034258] system_call_exception+0x138/0x330
[   37.852298] [c000000227b8be50] [c00000000000d05c] system_call_vectored_common+0x15c/0x2ec
[   37.852305] --- interrupt: 3000 at 0x7fff8010c2c4
[   37.852312] NIP:  00007fff8010c2c4 LR: 0000000000000000 CTR: 0000000000000000
[   37.852316] REGS: c000000227b8be80 TRAP: 3000   Tainted: G   M        E       (6.6.0-rc3-00055-g9ed22ae6be81)
[   37.852321] MSR:  800000000280f033 <SF,VEC,VSX,EE,PR,FP,ME,IR,DR,RI,LE>  CR: 44002822  XER: 00000000
[   37.852332] IRQMASK: 0
[   37.852332] GPR00: 00000000000000ea 00007ffff243d010 00007fff803f7e00 0000000000000000
[   37.852332] GPR04: 0000000000000000 000000003a4602a0 0000000000000000 0000000000000000
[   37.852332] GPR08: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
[   37.852332] GPR12: 0000000000000000 00007fff803fab60 0000000000000000 0000000000000000
[   37.852332] GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
[   37.852332] GPR20: 0000000000000000 0000000000000000 0000000000000001 0000000000000001
[   37.852332] GPR24: 00007fff802423c0 0000000000000000 00007fff80240a38 0000000000000000
[   37.852332] GPR28: 0000000000000001 00007fff803f3b70 fffffffffffff000 0000000000000000
[   37.852374] NIP [00007fff8010c2c4] 0x7fff8010c2c4
[   37.852378] LR [0000000000000000] 0x0
[   37.852381] --- interrupt: 3000
[   37.852383] Code: 38210030 38e00001 ebe1fff8 4bfff46c 38210030 38800000 ebe1fff8 4bffe9ec 38c00007 4bffff38 60000000 60000000 <0fe00000> 38800001 7fe3fb78 4bffe9cd
[   37.852398] ---[ end trace 0000000000000000 ]---
# test: inject-ra-err

git bisect points to following patch
e43c0a0c3c2870e1ee29519dc249471adf19ab5
    powerpc/64s/radix: combine final TLB flush and lazy tlb mm shootdown IPIs


- Sachin