FYI, we noticed the following commit (built with gcc-6):

commit: 47bd678bc7c0d70ffbf18580cc361894b595c0ef ("mm: Simplify and batch working set shadow pages LRU isolation locking")
url: https://github.com/0day-ci/linux/commits/Andi-Kleen/mm-Simplify-and-batch-working-set-shadow-pages-LRU-isolation-locking/20171029-215419


in testcase: vm-scalability
with following parameters:

	runtime: 300s
	test: mremap-xread-rand-mt
	cpufreq_governor: performance

test-description: The motivation behind this suite is to exercise functions and regions of the mm/ of the Linux kernel which are of interest to us.
test-url: https://git.kernel.org/cgit/linux/kernel/git/wfg/vm-scalability.git/


on test machine: 4 threads Intel(R) Core(TM) i3-3220 CPU @ 3.30GHz with 8G memory

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


kern  :warn  : [  348.637225] WARNING: CPU: 3 PID: 53 at mm/workingset.c:456 scan_shadow_nodes+0x240/0x260
kern  :warn  : [  348.638448] Modules linked in: xfs loop rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver netconsole snd_hda_codec_idt snd_hda_codec_generic sd_mod sr_mod cdrom sg intel_rapl x86_pkg_temp_thermal intel_powerclamp coretemp kvm irqbypass crct10dif_pclmul crc32_pclmul crc32c_intel snd_hda_intel ahci snd_hda_codec libahci i915 snd_hda_core snd_hwdep snd_pcm ghash_clmulni_intel cryptd pcspkr snd_timer drm_kms_helper snd syscopyarea sysfillrect sysimgblt libata soundcore fb_sys_fops drm shpchp video ip_tables
kern  :warn  : [  348.643659] CPU: 3 PID: 53 Comm: kswapd0 Not tainted 4.14.0-rc6-00001-g47bd678 #3
kern  :warn  : [  348.644941] Hardware name: Hewlett-Packard p6-1451cx/2ADA, BIOS 8.15 02/05/2013
kern  :warn  : [  348.646248] task: ffff8801db8fcd00 task.stack: ffffc90000ff8000
kern  :warn  : [  348.647549] RIP: 0010:scan_shadow_nodes+0x240/0x260
kern  :warn  : [  348.649378] RSP: 0000:ffffc90000ffbca8 EFLAGS: 00010097
kern  :warn  : [  348.650696] RAX: 0000000000000004 RBX: ffff88005759cdc8 RCX: ffff880158b244b8
kern  :warn  : [  348.652067] RDX: 0000000000100000 RSI: ffff880158b246b8 RDI: ffff8801ccc3c2e8
kern  :warn  : [  348.653469] RBP: ffffc90000ffbcf0 R08: 0000000000100000 R09: 0000000000000000
kern  :warn  : [  348.655431] R10: 0000000000000000 R11: 0000000000020440 R12: ffff8801ccc3c2e8
kern  :warn  : [  348.657415] R13: ffff8801ccc3c2d8 R14: ffff8801ccc3c2e8 R15: ffff880158b244a8
kern  :warn  : [  348.658849] FS:  0000000000000000(0000) GS:ffff880213380000(0000) knlGS:0000000000000000
kern  :warn  : [  348.660912] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
kern  :warn  : [  348.662958] CR2: 00007ade5947f628 CR3: 0000000001e09006 CR4: 00000000001606e0
kern  :warn  : [  348.664458] Call Trace:
kern  :warn  : [  348.666494]  shrink_slab+0x1ea/0x430
kern  :warn  : [  348.667974]  shrink_node+0x2da/0x2e0
kern  :warn  : [  348.669443]  kswapd+0x37e/0x760
kern  :warn  : [  348.670913]  kthread+0x114/0x150
kern  :warn  : [  348.672389]  ? mem_cgroup_shrink_node+0x160/0x160
kern  :warn  : [  348.673904]  ? kthread_create_on_node+0x40/0x40
kern  :warn  : [  348.675425]  ret_from_fork+0x25/0x30
kern  :warn  : [  348.676937] Code: 41 5e 41 5f 5d c3 0f ff 48 8d 55 c8 48 8b 03 49 89 df 48 39 d3 74 bf 48 89 c3 e9 35 fe ff ff 0f ff eb e5 0f ff eb e1 0f ff eb dd <0f> ff eb d9 0f ff eb d5 48 8b 15 41 06 c3 00 e9 f6 fe ff ff 66 
kern  :warn  : [  348.680371] ---[ end trace eca47a903e597e92 ]---


To reproduce:

        git clone https://github.com/intel/lkp-tests.git
        cd lkp-tests
        bin/lkp install job.yaml  # job file is attached in this email
        bin/lkp run     job.yaml



Thanks,
Xiaolong