From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal Nazarewicz Subject: Re: PROBLEM-PERSISTS: dmesg spam: alloc_contig_range: [XX, YY) PFNs busy Date: Wed, 30 Nov 2016 14:08:00 +0100 Message-ID: References: <20161130092239.GD18437@dhcp22.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <20161130092239.GD18437@dhcp22.suse.cz> Sender: linux-kernel-owner@vger.kernel.org To: Michal Hocko , "Robin H. Johnson" Cc: linux-kernel@vger.kernel.org, robbat2@gentoo.org, linux-mm@kvack.org List-Id: linux-mm.kvack.org On Wed, Nov 30 2016, Michal Hocko wrote: > [Let's CC linux-mm and Michal] > > On Tue 29-11-16 22:43:08, Robin H. Johnson wrote: >> I didn't get any responses to this. >>=20 >> git bisect shows that the problem did actually exist in 4.5.0-rc6, but >> has gotten worse by many orders of magnitude (< 1/week to ~20M/hour). >>=20 >> Presently with 4.9-rc5, it's now writing ~2.5GB/hour to syslog. > > This is really not helpful. I think we should simply make it pr_debug or > need some ratelimitting. AFAIU the message is far from serious On the other hand, if this didn=E2=80=99t happen and now happens all the ti= me, this indicates a regression in CMA=E2=80=99s capability to allocate pages so just rate limiting the output would hide the potential actual issue. >=20=20 >> The list of addresses in that time is only ~80 unique ranges, each >> appearing ~320K times. They don't appear exactly in order, so the kernel >> does not squelch the log message for appearing too frequently. >>=20 >> Could somebody at least make a suggestion on how to trace the printed >> range to somewhere in the kernel? >>=20 >> On Sat, Nov 19, 2016 at 03:25:32AM +0000, Robin H. Johnson wrote: >> > (Replies CC to list and direct to me please) >> >=20 >> > Summary: >> > -------- >> > dmesg spammed with alloc_contig_range: [XX, YY) PFNs busy >> >=20 >> > Description: >> > ------------ >> > I recently upgrading 4.9-rc5, (previous kernel 4.5.0-rc6-00141-g679440= 2),=20 >> > and since then my dmesg has been absolutely flooded with 'PFNs busy' >> > (>3GiB/day). My config did not change (all new options =3Dn). >> >=20 >> > 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 >> >=20 >> > Keywords: >> > --------- >> > mm, alloc_contig_range, CMA >> >=20 >> > Most recent kernel version which did not have the bug: >> > ------------------------------------------------------ >> > Known 4.5.0-rc6-00141-g6794402 >> >=20 >> > 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 >> >=20 >> > 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 cdr= om >> > 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_s= mq >> > 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 lp= fc >> > 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 >>=20 >> --=20 >> Robin Hugh Johnson >> E-Mail : robbat2@orbis-terrarum.net >> Home Page : http://www.orbis-terrarum.net/?l=3Dpeople.robbat2 >> ICQ# : 30269588 or 41961639 >> GnuPG FP : 11ACBA4F 4778E3F6 E4EDF38E B27B944E 34884E85 > > > > --=20 > Michal Hocko > SUSE Labs --=20 Best regards =E3=83=9F=E3=83=8F=E3=82=A6 =E2=80=9C=F0=9D=93=B6=F0=9D=93=B2=F0=9D=93=B7= =F0=9D=93=AA86=E2=80=9D =E3=83=8A=E3=82=B6=E3=83=AC=E3=83=B4=E3=82=A4=E3=83= =84 =C2=ABIf at first you don=E2=80=99t succeed, give up skydiving=C2=BB