next: WARNING: at mm/hugetlb.c:2918 due to 'proc-mm-export-pte-sizes-directly-in-smaps-v3'

[Guenter Roeck]

Hi Dave,

I see the following runtime warning when running next-20161201 in qemu
for ppc64:pseries with pseries_defconfig.

------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at mm/hugetlb.c:2918 .hugetlb_add_hstate+0x1e0/0x208
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.9.0-rc7-next-20161201 #1
task: c00000003e4a0000 task.stack: c00000003e4c0000
NIP: c000000000c422f8 LR: c000000000c42294 CTR: c00000000049e740
REGS: c00000003e4c37c0 TRAP: 0700   Not tainted  (4.9.0-rc7-next-20161201)
MSR: 8000000002029032 <SF,VEC,EE,ME,IR,DR,RI>  CR: 88000022  XER: 20000000
CFAR: c00000000049e9b4 SOFTE: 1 
GPR00: c000000000c42294 c00000003e4c3a40 c000000000e7cb00 0000000000000014 
GPR04: c000000000b3b047 0000000000000002 fffffffffffffff4 c000000000d2cb00 
GPR08: c000000000c7cb00 0000000000000001 0000000000000000 000000000000005f 
GPR12: 0000000088000028 c00000000fe00000 c00000000000dac0 0000000000000000 
GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 
GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 
GPR24: 0000000000000000 c000000000dc52c8 0000000000000020 c000000000ec1128 
GPR28: 0000000000001c78 c000000000fa2970 0000000400000000 c000000000fa45e8 
NIP [c000000000c422f8] .hugetlb_add_hstate+0x1e0/0x208
LR [c000000000c42294] .hugetlb_add_hstate+0x17c/0x208
Call Trace:
[c00000003e4c3a40] [c000000000c42294] .hugetlb_add_hstate+0x17c/0x208
(unreliable)
[c00000003e4c3ae0] [c000000000c22ae0] .add_huge_page_size+0xb0/0xd0
[c00000003e4c3b60] [c000000000c22bb4] .hugetlbpage_init+0x50/0x194
[c00000003e4c3c00] [c00000000000d1ec] .do_one_initcall+0x5c/0x1d0
[c00000003e4c3ce0] [c000000000c146e4] .kernel_init_freeable+0x280/0x360
[c00000003e4c3db0] [c00000000000dadc] .kernel_init+0x1c/0x140
[c00000003e4c3e30] [c00000000000badc] .ret_from_kernel_thread+0x58/0x7c
Instruction dump:
7d0807b4 394a0010 7d0a5036 3d02ffe0 7fbe5040 fbe80b20 41fc001c 3ce2ffeb 
89479154 2f8a0000 40fe000c 99279154 <0fe00000> 382100a0 e8010010 eb61ffd8 
---[ end trace c1cc0a7853b176ea ]---

Scripts used to reproduce the problem are at
https://github.com/groeck/linux-build-test/tree/master/rootfs/ppc64

A log is available at
http://kerneltests.org/builders/qemu-ppc64-next/builds/517/steps/qemubuildcommand/logs/stdio

Please let me know if there is anything I can do to help tracking down
the problem.

Thanks,
Guenter