FYI, we noticed the following commit:

commit: ec1f2e572e0c12ab154997221026e451d54e14d5 ("percpu: replace area map allocator with bitmap allocator")
url: https://github.com/0day-ci/linux/commits/Dennis-Zhou/percpu-replace-percpu-area-map-allocator-with-bitmap-allocator/20170725-204840
base: https://git.kernel.org/cgit/linux/kernel/git/tj/percpu.git for-next

in testcase: boot

on test machine: qemu-system-x86_64 -enable-kvm -m 420M

caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):


+-----------------------------------------------+------------+------------+
|                                               | 1aba53fc6c | ec1f2e572e |
+-----------------------------------------------+------------+------------+
| boot_successes                                | 13         | 0          |
| boot_failures                                 | 0          | 10         |
| WARNING:at_lib/list_debug.c:#__list_add_valid | 0          | 10         |
| WARNING:at_mm/percpu.c:#pcpu_mem_zalloc       | 0          | 10         |
| BUG:kernel_hang_in_boot_stage                 | 0          | 10         |
+-----------------------------------------------+------------+------------+



[    0.000000] WARNING: CPU: 0 PID: 0 at lib/list_debug.c:25 __list_add_valid+0x3b/0x80
[    0.000000] Modules linked in:
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.13.0-rc1-00018-gec1f2e5 #1
[    0.000000] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-20161025_171302-gandalf 04/01/2014
[    0.000000] task: ffffffff81e10480 task.stack: ffffffff81e00000
[    0.000000] RIP: 0010:__list_add_valid+0x3b/0x80
[    0.000000] RSP: 0000:ffffffff81e03da0 EFLAGS: 00010086 ORIG_RAX: 0000000000000000
[    0.000000] RAX: 0000000000000075 RBX: ffff88001888ea00 RCX: ffffffff81e61588
[    0.000000] RDX: 0000000000000001 RSI: 0000000000000082 RDI: 0000000000000046
[    0.000000] RBP: ffffffff81e03da0 R08: 6464615f7473696c R09: 0000000000000080
[    0.000000] R10: ffff88001888e558 R11: 202e6e6f69747075 R12: ffff88001888e500
[    0.000000] R13: ffff88001888ea00 R14: 0000000000007ba8 R15: ffffffff820a17e0
[    0.000000] FS:  0000000000000000(0000) GS:ffffffff820c2000(0000) knlGS:0000000000000000
[    0.000000] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    0.000000] CR2: ffff880002514000 CR3: 0000000001e09000 CR4: 00000000000006b0
[    0.000000] Call Trace:
[    0.000000]  pcpu_chunk_relocate+0xc7/0x110
[    0.000000]  pcpu_setup_first_chunk+0x677/0x695
[    0.000000]  pcpu_embed_first_chunk+0x240/0x2c7
[    0.000000]  ? pcpup_populate_pte+0x10/0x10
[    0.000000]  setup_per_cpu_areas+0x66/0x23e
[    0.000000]  start_kernel+0x126/0x400
[    0.000000]  ? early_idt_handler_array+0x120/0x120
[    0.000000]  x86_64_start_reservations+0x2a/0x2c
[    0.000000]  x86_64_start_kernel+0x13e/0x14d
[    0.000000]  secondary_startup_64+0x9f/0x9f
[    0.000000] Code: 49 8b 10 48 39 d0 75 29 49 39 f8 74 3c 48 39 f8 74 37 b8 01 00 00 00 5d c3 48 89 d1 48 c7 c7 10 18 cf 81 4c 89 c2 e8 06 c3 c2 ff <0f> ff 31 c0 5d c3 4c 89 c1 48 89 c6 48 c7 c7 88 18 cf 81 e8 ee 
[    0.000000] ---[ end trace be658dd14e22cef1 ]---


To reproduce:

        git clone https://github.com/01org/lkp-tests.git
        cd lkp-tests
        bin/lkp qemu -k <bzImage> job-script  # job-script is attached in this email



Thanks,
Kernel Test Robot