Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753481AbdHUB1A (ORCPT ); Sun, 20 Aug 2017 21:27:00 -0400 Received: from mail-oi0-f47.google.com ([209.85.218.47]:36743 "EHLO mail-oi0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753439AbdHUB06 (ORCPT ); Sun, 20 Aug 2017 21:26:58 -0400 MIME-Version: 1.0 In-Reply-To: <20170820231302.s732zclznrqxwr46@angband.pl> References: <20170820231302.s732zclznrqxwr46@angband.pl> From: Wanpeng Li Date: Mon, 21 Aug 2017 09:26:57 +0800 Message-ID: Subject: Re: kvm splat in mmu_spte_clear_track_bits To: Adam Borowski Cc: Paolo Bonzini , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , kvm , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by nfs id v7L1RE0t018742 Content-Length: 3140 Lines: 69 2017-08-21 7:13 GMT+08:00 Adam Borowski : > Hi! > I'm afraid I keep getting a quite reliable, but random, splat when running > KVM: I reported something similar before. https://lkml.org/lkml/2017/6/29/64 Regards, Wanpeng Li > > ------------[ cut here ]------------ > WARNING: CPU: 5 PID: 5826 at arch/x86/kvm/mmu.c:717 mmu_spte_clear_track_bits+0x123/0x170 > Modules linked in: tun nbd arc4 rtl8xxxu mac80211 cfg80211 rfkill nouveau video ttm > CPU: 5 PID: 5826 Comm: qemu-system-x86 Not tainted 4.13.0-rc5-vanilla-ubsan-00211-g7f680d7ec315 #1 > Hardware name: System manufacturer System Product Name/M4A77T, BIOS 2401 05/18/2011 > task: ffff880207ef0400 task.stack: ffffc900035e4000 > RIP: 0010:mmu_spte_clear_track_bits+0x123/0x170 > RSP: 0018:ffffc900035e7ab0 EFLAGS: 00010246 > RAX: 0000000000000000 RBX: 000000010501cc67 RCX: 0000000000000001 > RDX: dead0000000000ff RSI: ffff88020e501df8 RDI: 0000000004140700 > RBP: ffffc900035e7ad8 R08: 0000000000000100 R09: 0000000000000003 > R10: 0000000000000003 R11: 0000000000000005 R12: 000000000010501c > R13: ffffea0004140700 R14: ffff88020e1d0000 R15: 0000000000000000 > FS: 00007f0213fbd700(0000) GS:ffff88022fd40000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000000000000 CR3: 000000022187f000 CR4: 00000000000006e0 > Call Trace: > drop_spte+0x26/0x130 > mmu_page_zap_pte+0xc4/0x160 > kvm_mmu_prepare_zap_page+0x65/0x660 > kvm_mmu_invalidate_zap_all_pages+0xc5/0x1f0 > kvm_mmu_invalidate_zap_pages_in_memslot+0x9/0x10 > kvm_page_track_flush_slot+0x86/0xd0 > kvm_arch_flush_shadow_memslot+0x9/0x10 > __kvm_set_memory_region+0x8fb/0x14f0 > kvm_set_memory_region+0x2f/0x50 > kvm_vm_ioctl+0x559/0xcc0 > ? kvm_vcpu_ioctl+0x171/0x620 > ? __switch_to+0x30b/0x740 > do_vfs_ioctl+0xbb/0x8d0 > ? find_vma+0x23/0x100 > ? __fget_light+0x94/0x110 > SyS_ioctl+0x86/0xa0 > entry_SYSCALL_64_fastpath+0x17/0x98 > RIP: 0033:0x7f021c80ddc7 > RSP: 002b:00007f0213fbc518 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 > RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f021c80ddc7 > RDX: 00007f0213fbc5b0 RSI: 000000004020ae46 RDI: 000000000000000a > RBP: 0000000000000000 R08: 00007f020c1698a0 R09: 0000000000000000 > R10: 00007f020c1698a0 R11: 0000000000000246 R12: 0000000000000006 > R13: 00007f022201c000 R14: 0000000000000002 R15: 0000558c3899e550 > Code: ae fc 01 48 85 c0 75 1c 4c 89 e7 e8 98 de fd ff 48 8b 05 81 ae fc 01 48 85 c0 74 ba 48 85 c3 0f 95 c3 eb b8 48 85 c3 74 e7 eb dd <0f> ff eb 97 4c 89 e7 66 0f 1f 44 00 00 e8 6b de fd ff eb 97 31 > ---[ end trace 16c196134f0dd0a9 ]--- > > After this, there are hundreds of repeats and lots of secondary damage which > kills the host quickly. > > Usually this happens within a few minutes, but sometimes it takes ~half an > hour to reproduce. Because of this, it'd be unpleasant to bisect -- is this > problem already known? > > > Meow! > -- > ⢀⣴⠾⠻⢶⣦⠀ > ⣾⠁⢰⠒⠀⣿⡁ Vat kind uf sufficiently advanced technology iz dis!? > ⢿⡄⠘⠷⠚⠋⠀ -- Genghis Ht'rok'din > ⠈⠳⣄⠀⠀⠀⠀