On Wed, Aug 30, 2017, at 10:57 AM, Adam Borowski wrote: > On Tue, Aug 29, 2017 at 08:56:15PM -0400, Jerome Glisse wrote: > > I will wait for people to test and for result of my own test before > > reposting if need be, otherwise i will post as separate patch. > > > > > But from a _very_ quick read-through this looks fine. But it obviously > > > needs testing. > > > > > > People - *especially* the people who saw issues under KVM - can you > > > try out Jérôme's patch-series? I aded some people to the cc, the full > > > series is on lkml. Jérôme - do you have a git branch for people to > > > test that they could easily pull and try out? > > > > https://cgit.freedesktop.org/~glisse/linux mmu-notifier branch > > git://people.freedesktop.org/~glisse/linux > > Tested your branch as of 10f07641, on a long list of guest VMs. > No earth-shattering kaboom. I've been using the mmu_notifier branch @ a3d944233bcf8c for the last 36 hours or so, also without incident. Unlike most other reporters, I experienced a similar splat on 4.12: Aug 03 15:02:47 kvm_master kernel: ------------[ cut here ]------------ Aug 03 15:02:47 kvm_master kernel: WARNING: CPU: 13 PID: 1653 at arch/x86/kvm/mmu.c:682 mmu_spte_clear_track_bits+0xfb/0x100 [kvm] Aug 03 15:02:47 kvm_master kernel: Modules linked in: vhost_net vhost tap xt_conntrack xt_CHECKSUM iptable_mangle ipt_REJECT nf_reject_ipv4 xt_tcpudp tun ebtable_filter ebtables ip6table_filter ip6_tables iptable_filter msr nls_iso8859_1 nls_cp437 intel_rapl ipt_ MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack sb_edac x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel input_leds pcbc aesni_intel led_class aes_x86_6 4 mxm_wmi crypto_simd glue_helper uvcvideo cryptd videobuf2_vmalloc videobuf2_memops igb videobuf2_v4l2 videobuf2_core snd_usb_audio videodev media joydev ptp evdev mousedev intel_cstate pps_core mac_hid intel_rapl_perf snd_hda_intel snd_virtuoso snd_usbmidi_lib snd_hda_codec snd_oxygen_lib snd_hda_core Aug 03 15:02:47 kvm_master kernel: snd_mpu401_uart snd_rawmidi snd_hwdep snd_seq_device snd_pcm snd_timer snd soundcore i2c_algo_bit pcspkr i2c_i801 lpc_ich ioatdma shpchp dca wmi acpi_power_meter tpm_tis tpm_tis_core tpm button bridge stp llc sch_fq_codel virtio_pci virtio_blk virtio_balloon virtio_net virtio_ring virtio kvm_intel kvm sg ip_tables x_tables hid_logitech_hidpp hid_logitech_dj hid_generic hid_microsoft usbhid hid sr_mod cdrom sd_mod xhci_pci ahci libahci xhci_hcd libata usbcore scsi_mod usb_common zfs(PO) zunicode(PO) zavl(PO) icp(PO) zcommon(PO) znvpair(PO) spl(O) drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops drm vfio_pci irqbypass vfio_virqfd vfio_iommu_type1 vfio vfat fat ext4 crc16 jbd2 fscrypto mbcache dm_thin_pool dm_cache dm_persistent_data dm_bio_prison dm_bufio dm_raid raid456 libcrc32c Aug 03 15:02:47 kvm_master kernel: crc32c_generic crc32c_intel async_raid6_recov async_memcpy async_pq async_xor xor async_tx raid6_pq dm_mod dax raid1 md_mod Aug 03 15:02:47 kvm_master kernel: CPU: 13 PID: 1653 Comm: kworker/13:2 Tainted: P B D W O 4.12.3-1-ARCH #1 Aug 03 15:02:47 kvm_master kernel: Hardware name: Supermicro SYS-7038A-I/X10DAI, BIOS 2.0a 11/09/2016 Aug 03 15:02:47 kvm_master kernel: Workqueue: events mmput_async_fn Aug 03 15:02:47 kvm_master kernel: task: ffff9fa89751b900 task.stack: ffffc179880d8000 Aug 03 15:02:47 kvm_master kernel: RIP: 0010:mmu_spte_clear_track_bits+0xfb/0x100 [kvm] Aug 03 15:02:47 kvm_master kernel: RSP: 0018:ffffc179880dbc20 EFLAGS: 00010246 Aug 03 15:02:47 kvm_master kernel: RAX: 0000000000000000 RBX: 00000009c07cce77 RCX: dead0000000000ff Aug 03 15:02:47 kvm_master kernel: RDX: 0000000000000000 RSI: ffff9fa82d6d6f08 RDI: fffff6e76701f300 Aug 03 15:02:47 kvm_master kernel: RBP: ffffc179880dbc38 R08: 0000000000100000 R09: 000000000000000d Aug 03 15:02:47 kvm_master kernel: R10: ffff9fa0a56b0008 R11: ffff9fa0a56b0000 R12: 00000000009c07cc Aug 03 15:02:47 kvm_master kernel: R13: ffff9fa88b990000 R14: ffff9f9e19dbb1b8 R15: 0000000000000000 Aug 03 15:02:47 kvm_master kernel: FS: 0000000000000000(0000) GS:ffff9fac5f340000(0000) knlGS:0000000000000000 Aug 03 15:02:47 kvm_master kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Aug 03 15:02:47 kvm_master kernel: CR2: ffffd1b542d71000 CR3: 0000000570a09000 CR4: 00000000003426e0 Aug 03 15:02:47 kvm_master kernel: DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 Aug 03 15:02:47 kvm_master kernel: DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Aug 03 15:02:47 kvm_master kernel: Call Trace: Aug 03 15:02:47 kvm_master kernel: drop_spte+0x1a/0xb0 [kvm] Aug 03 15:02:47 kvm_master kernel: mmu_page_zap_pte+0x9c/0xe0 [kvm] Aug 03 15:02:47 kvm_master kernel: kvm_mmu_prepare_zap_page+0x65/0x310 [kvm] Aug 03 15:02:47 kvm_master kernel: kvm_mmu_invalidate_zap_all_pages+0x10d/0x160 [kvm] Aug 03 15:02:47 kvm_master kernel: kvm_arch_flush_shadow_all+0xe/0x10 [kvm] Aug 03 15:02:47 kvm_master kernel: kvm_mmu_notifier_release+0x2c/0x40 [kvm] Aug 03 15:02:47 kvm_master kernel: __mmu_notifier_release+0x44/0xc0 Aug 03 15:02:47 kvm_master kernel: exit_mmap+0x142/0x150 Aug 03 15:02:47 kvm_master kernel: ? kfree+0x175/0x190 Aug 03 15:02:47 kvm_master kernel: ? kfree+0x175/0x190 Aug 03 15:02:47 kvm_master kernel: ? exit_aio+0xc6/0x100 Aug 03 15:02:47 kvm_master kernel: mmput_async_fn+0x4c/0x130 Aug 03 15:02:47 kvm_master kernel: process_one_work+0x1de/0x430 Aug 03 15:02:47 kvm_master kernel: worker_thread+0x47/0x3f0 Aug 03 15:02:47 kvm_master kernel: kthread+0x125/0x140 Aug 03 15:02:47 kvm_master kernel: ? process_one_work+0x430/0x430 Aug 03 15:02:47 kvm_master kernel: ? kthread_create_on_node+0x70/0x70 Aug 03 15:02:47 kvm_master kernel: ret_from_fork+0x25/0x30 Aug 03 15:02:47 kvm_master kernel: Code: ec 75 04 00 48 b8 00 00 00 00 00 00 00 40 48 21 da 48 39 c2 0f 95 c0 eb b2 48 d1 eb 83 e3 01 eb c0 4c 89 e7 e8 f7 3d fe ff eb a4 <0f> ff eb 8a 90 0f 1f 44 00 00 55 48 89 e5 53 89 d3 e8 ff 4a fe Aug 03 15:02:47 kvm_master kernel: ---[ end trace 8710f4d700a7d36e ]--- This would typically take 36-48 hours to surface, so we're good so far, but not completely out of the woods yet. I'm optimistic that since this patchset changes the mmu_notifier behavior to something safer in general, this issue will also be resolved by it. Jeff > > > Meow! > -- > ⢀⣴⠾⠻⢶⣦⠀ > ⣾⠁⢰⠒⠀⣿⡁ Vat kind uf sufficiently advanced technology iz dis!? > ⢿⡄⠘⠷⠚⠋⠀ -- Genghis Ht'rok'din > ⠈⠳⣄⠀⠀⠀⠀
