PROBLEM: dmesg spam: alloc_contig_range: [XX, YY) PFNs busy

[Robin H. Johnson]

(Replies CC to list and direct to me please)

Summary:
--------
dmesg spammed with alloc_contig_range: [XX, YY) PFNs busy

Description:
------------
I recently upgrading 4.9-rc5, (previous kernel 4.5.0-rc6-00141-g6794402), 
and since then my dmesg has been absolutely flooded with 'PFNs busy'
(>3GiB/day). My config did not change (all new options =n).

It's not consistent addresses, so the squelch of identical printk lines
hasn't helped.
Eg output:
[187487.621916] alloc_contig_range: [83f0a9, 83f0aa) PFNs busy
[187487.621924] alloc_contig_range: [83f0ce, 83f0cf) PFNs busy
[187487.621976] alloc_contig_range: [83f125, 83f126) PFNs busy
[187487.622013] alloc_contig_range: [83f127, 83f128) PFNs busy

Keywords:
---------
mm, alloc_contig_range, CMA

Most recent kernel version which did not have the bug:
------------------------------------------------------
Known 4.5.0-rc6-00141-g6794402

ver_linux:
----------
Linux bohr-int 4.9.0-rc5-00177-g81bcfe5 #12 SMP Wed Nov 16 13:16:32 PST
2016 x86_64 Intel(R) Core(TM) i7-2600K CPU @ 3.40GHz GenuineIntel
GNU/Linux

GNU C					5.3.0
GNU Make				4.2.1
Binutils				2.25.1
Util-linux				2.29
Mount					2.29
Quota-tools				4.03
Linux C Library			2.23
Dynamic linker (ldd)	2.23
readlink: missing operand
Try 'readlink --help' for more information.
Procps					3.3.12
Net-tools				1.60
Kbd						2.0.3
Console-tools			2.0.3
Sh-utils				8.25
Udev					230
Modules Loaded			3w_sas 3w_xxxx ablk_helper aesni_intel
aes_x86_64 af_packet ahci aic79xx amdgpu async_memcpy async_pq
async_raid6_recov async_tx async_xor ata_piix auth_rpcgss binfmt_misc
bluetooth bnep bnx2 bonding btbcm btintel btrfs btrtl btusb button cdrom
cn configs coretemp crc32c_intel crc32_pclmul crc_ccitt crc_itu_t
crct10dif_pclmul cryptd dca dm_bio_prison dm_bufio dm_cache dm_cache_smq
dm_crypt dm_delay dm_flakey dm_log dm_log_userspace dm_mirror dm_mod
dm_multipath dm_persistent_data dm_queue_length dm_raid dm_region_hash
dm_round_robin dm_service_time dm_snapshot dm_thin_pool dm_zero drm
drm_kms_helper dummy e1000 e1000e evdev ext2 fat fb_sys_fops
firewire_core firewire_ohci fjes fscache fuse ghash_clmulni_intel
glue_helper grace hangcheck_timer hid_a4tech hid_apple hid_belkin
hid_cherry hid_chicony hid_cypress hid_ezkey hid_generic hid_gyration
hid_logitech hid_logitech_dj hid_microsoft hid_monterey hid_petalynx
hid_pl hid_samsung hid_sony hid_sunplus hwmon_vid i2c_algo_bit i2c_i801
i2c_smbus igb input_leds intel_rapl ip6_udp_tunnel ipv6 irqbypass
iscsi_tcp iTCO_vendor_support iTCO_wdt ixgb ixgbe jfs kvm kvm_intel
libahci libata libcrc32c libiscsi libiscsi_tcp linear lockd lpc_ich lpfc
lrw macvlan mdio md_mod megaraid_mbox megaraid_mm megaraid_sas mii
mptbase mptfc mptsas mptscsih mptspi multipath nfs nfs_acl nfsd
nls_cp437 nls_iso8859_1 nvram ohci_hcd pata_jmicron pata_marvell
pata_platform pcspkr psmouse qla1280 qla2xxx r8169 radeon raid0 raid10
raid1 raid456 raid6_pq reiserfs rfkill sata_mv sata_sil24
scsi_transport_fc scsi_transport_iscsi scsi_transport_sas
scsi_transport_spi sd_mod sg sky2 snd snd_hda_codec
snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_codec_realtek
snd_hda_core snd_hda_intel snd_hwdep snd_pcm snd_timer soundcore sr_mod
sunrpc syscopyarea sysfillrect sysimgblt tg3 ttm uas udp_tunnel
usb_storage vfat virtio virtio_net virtio_ring vxlan w83627ehf
x86_pkg_temp_thermal xfs xhci_hcd xhci_pci xor zlib_deflate



-- 
Robin Hugh Johnson
Gentoo Linux: Dev, Infra Lead, Foundation Trustee & Treasurer
E-Mail   : robbat2@xxxxxxxxxx
GnuPG FP : 11ACBA4F 4778E3F6 E4EDF38E B27B944E 34884E85
GnuPG FP : 7D0B3CEB E9B85B1F 825BCECF EE05E6F6 A48F6136

Attachment: signature.asc
Description: Digital signature