(Sorry for so many list cross-posting and big cc)
Please help testing !
The invalidate_page callback suffered from 2 pitfalls. First it used to happen after page table lock was release and thus a new page might have been setup for the virtual address before the call to invalidate_page().
This is in a weird way fixed by c7ab0d2fdc840266b39db94538f74207ec2afbf6 which moved the callback under the page table lock. Which also broke several existing user of the mmu_notifier API that assumed they could sleep inside this callback.
The second pitfall was invalidate_page being the only callback not taking a range of address in respect to invalidation but was giving an address and a page. Lot of the callback implementer assumed this could never be THP and thus failed to invalidate the appropriate range for THP pages.
By killing this callback we unify the mmu_notifier callback API to always take a virtual address range as input.
There is now 2 clear API (I am not mentioning the youngess API which is seldomly used): - invalidate_range_start()/end() callback (which allow you to sleep) - invalidate_range() where you can not sleep but happen right after page table update under page table lock
Note that a lot of existing user feels broken in respect to range_start/ range_end. Many user only have range_start() callback but there is nothing preventing them to undo what was invalidated in their range_start() callback after it returns but before any CPU page table update take place.
The code pattern use in kvm or umem odp is an example on how to properly avoid such race. In a nutshell use some kind of sequence number and active range invalidation counter to block anything that might undo what the range_start() callback did.
If you do not care about keeping fully in sync with CPU page table (ie you can live with CPU page table pointing to new different page for a given virtual address) then you can take a reference on the pages inside the range_start callback and drop it in range_end or when your driver is done with those pages.
Last alternative is to use invalidate_range() if you can do invalidation without sleeping as invalidate_range() callback happens under the CPU page table spinlock right after the page table is updated.
Note this is barely tested. I intend to do more testing of next few days but i do not have access to all hardware that make use of the mmu_notifier API.
First 2 patches convert existing call of mmu_notifier_invalidate_page() to mmu_notifier_invalidate_range() and bracket those call with call to mmu_notifier_invalidate_range_start()/end().
The next 10 patches remove existing invalidate_page() callback as it can no longer happen.
Finaly the last page remove it completely so it can RIP.
Jérôme Glisse (13): dax: update to new mmu_notifier semantic mm/rmap: update to new mmu_notifier semantic powerpc/powernv: update to new mmu_notifier semantic drm/amdgpu: update to new mmu_notifier semantic IB/umem: update to new mmu_notifier semantic IB/hfi1: update to new mmu_notifier semantic iommu/amd: update to new mmu_notifier semantic iommu/intel: update to new mmu_notifier semantic misc/mic/scif: update to new mmu_notifier semantic sgi-gru: update to new mmu_notifier semantic xen/gntdev: update to new mmu_notifier semantic KVM: update to new mmu_notifier semantic mm/mmu_notifier: kill invalidate_page
Cc: Kirill A. Shutemov kirill.shutemov@linux.intel.com Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Andrew Morton akpm@linux-foundation.org Cc: Andrea Arcangeli aarcange@redhat.com Cc: Joerg Roedel jroedel@suse.de Cc: Dan Williams dan.j.williams@intel.com Cc: Sudeep Dutt sudeep.dutt@intel.com Cc: Ashutosh Dixit ashutosh.dixit@intel.com Cc: Dimitri Sivanich sivanich@sgi.com Cc: Jack Steiner steiner@sgi.com Cc: Paolo Bonzini pbonzini@redhat.com Cc: Radim Krčmář rkrcmar@redhat.com
Cc: linuxppc-dev@lists.ozlabs.org Cc: dri-devel@lists.freedesktop.org Cc: amd-gfx@lists.freedesktop.org Cc: linux-rdma@vger.kernel.org Cc: iommu@lists.linux-foundation.org Cc: xen-devel@lists.xenproject.org Cc: kvm@vger.kernel.org
arch/powerpc/platforms/powernv/npu-dma.c | 10 -------- drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c | 31 ---------------------- drivers/infiniband/core/umem_odp.c | 19 -------------- drivers/infiniband/hw/hfi1/mmu_rb.c | 9 ------- drivers/iommu/amd_iommu_v2.c | 8 ------ drivers/iommu/intel-svm.c | 9 ------- drivers/misc/mic/scif/scif_dma.c | 11 -------- drivers/misc/sgi-gru/grutlbpurge.c | 12 --------- drivers/xen/gntdev.c | 8 ------ fs/dax.c | 19 ++++++++------ include/linux/mm.h | 1 + include/linux/mmu_notifier.h | 25 ------------------ mm/memory.c | 26 +++++++++++++++---- mm/mmu_notifier.c | 14 ---------- mm/rmap.c | 44 +++++++++++++++++++++++++++++--- virt/kvm/kvm_main.c | 42 ------------------------------ 16 files changed, 74 insertions(+), 214 deletions(-)
On Tue, Aug 29, 2017 at 4:54 PM, Jérôme Glisse jglisse@redhat.com wrote:
Note this is barely tested. I intend to do more testing of next few days but i do not have access to all hardware that make use of the mmu_notifier API.
Thanks for doing this.
First 2 patches convert existing call of mmu_notifier_invalidate_page() to mmu_notifier_invalidate_range() and bracket those call with call to mmu_notifier_invalidate_range_start()/end().
Ok, those two patches are a bit more complex than I was hoping for, but not *too* bad.
And the final end result certainly looks nice:
16 files changed, 74 insertions(+), 214 deletions(-)
Yeah, removing all those invalidate_page() notifiers certainly makes for a nice patch.
And I actually think you missed some more lines that can now be removed: kvm_arch_mmu_notifier_invalidate_page() should no longer be needed either, so you can remove all of those too (most of them are empty inline functions, but x86 has one that actually does something.
So there's an added 30 or so dead lines that should be removed in the kvm patch, I think.
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?
Linus
On Tue, Aug 29, 2017 at 05:11:24PM -0700, Linus Torvalds wrote:
On Tue, Aug 29, 2017 at 4:54 PM, Jérôme Glisse jglisse@redhat.com wrote:
Note this is barely tested. I intend to do more testing of next few days but i do not have access to all hardware that make use of the mmu_notifier API.
Thanks for doing this.
First 2 patches convert existing call of mmu_notifier_invalidate_page() to mmu_notifier_invalidate_range() and bracket those call with call to mmu_notifier_invalidate_range_start()/end().
Ok, those two patches are a bit more complex than I was hoping for, but not *too* bad.
And the final end result certainly looks nice:
16 files changed, 74 insertions(+), 214 deletions(-)
Yeah, removing all those invalidate_page() notifiers certainly makes for a nice patch.
And I actually think you missed some more lines that can now be removed: kvm_arch_mmu_notifier_invalidate_page() should no longer be needed either, so you can remove all of those too (most of them are empty inline functions, but x86 has one that actually does something.
So there's an added 30 or so dead lines that should be removed in the kvm patch, I think.
Yes i missed that. 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
(Sorry if that tree is bit big it has a lot of dead thing i need to push a clean and slim one)
Jérôme
On Tue, 2017-08-29 at 20:56 -0400, Jerome Glisse wrote:
On Tue, Aug 29, 2017 at 05:11:24PM -0700, Linus Torvalds wrote:
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
Looks good here.
I reproduced fairly quickly with RT host and 1 RT guest by just having the guest do a parallel kbuild over NFS (the guest had to be restored afterward, was corrupted). I'm currently flogging 2 guests as well as the host, whimper free. I'll let the lot broil for while longer, but at this point, smoke/flame appearance seems comfortingly unlikely.
-Mike
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.
Meow!
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 ⠈⠳⣄⠀⠀⠀⠀
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On Sep 1, 2017 10:48 AM, Jeff Cook jeff@jeffcook.io wrote:
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 ⠈⠳⣄⠀⠀⠀⠀
dri-devel@lists.freedesktop.org
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Adam Borowski -
Jeff Cook -
Jerome Glisse -
Jérôme Glisse
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