On Fri, Jan 15, 2016 at 6:12 PM, Dmitry Vyukov <dvyukov@xxxxxxxxxx> wrote: > On Fri, Jan 8, 2016 at 7:42 PM, Dmitry Vyukov <dvyukov@xxxxxxxxxx> wrote: >> Hello, >> >> The following program triggers GPF in kvm_lapic_latched_init if run in >> a parallel loop: >> https://gist.githubusercontent.com/dvyukov/524b398f379440b21115/raw/9627095f57a72501fb51bf7565471d31732beeee/gistfile1.txt >> >> kasan: GPF could be caused by NULL-ptr deref or user memory >> accessgeneral protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN >> Modules linked in: >> CPU: 3 PID: 14426 Comm: a.out Not tainted 4.4.0-rc8+ #217 >> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 >> task: ffff880061099780 ti: ffff880062e30000 task.ti: ffff880062e30000 >> RIP: 0010:[<ffffffff81057171>] [<ffffffff81057171>] >> kvm_arch_vcpu_ioctl+0xa31/0x2ef0 >> RSP: 0018:ffff880062e37900 EFLAGS: 00010206 >> RAX: dffffc0000000000 RBX: 1ffff1000c5c6f25 RCX: 1ffff1000c41b7cb >> RDX: 000000000000001e RSI: 000000008040ae9f RDI: 00000000000000f0 >> RBP: ffff880062e37c10 R08: 0000000000000000 R09: 0000000000000000 >> R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 >> R13: 0000000000000000 R14: ffff880062e37be8 R15: 0000000000000000 >> FS: 00007f4aa815f700(0000) GS:ffff88006d700000(0000) knlGS:0000000000000000 >> CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b >> CR2: 00007f4aa795de78 CR3: 00000000613c2000 CR4: 00000000000026e0 >> Stack: >> 0000000000000000 0000000000000000 0000000000000000 0000000000000000 >> 0000000020006fe4 0000000041b58ab3 ffffffff86e2e588 ffffffff81056740 >> 0000000000000001 ffff880061099f60 0000000000000498 ffff880061099f68 >> Call Trace: >> [<ffffffff8101cb52>] kvm_vcpu_ioctl+0x1e2/0xd00 >> arch/x86/kvm/../../../virt/kvm/kvm_main.c:2526 >> [< inline >] vfs_ioctl fs/ioctl.c:43 >> [<ffffffff817b36b1>] do_vfs_ioctl+0x681/0xe40 fs/ioctl.c:607 >> [< inline >] SYSC_ioctl fs/ioctl.c:622 >> [<ffffffff817b3eff>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:613 >> [<ffffffff85e745b6>] entry_SYSCALL_64_fastpath+0x16/0x7a >> arch/x86/entry/entry_64.S:185 >> Code: 85 2d 20 00 00 4d 8b a4 24 60 03 00 00 e8 c8 8b 50 00 49 8d bc >> 24 f0 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> >> 3c 02 00 0f 85 f3 1f 00 00 4d 8b a4 24 f0 00 00 00 41 83 e4 >> RIP [< inline >] constant_test_bit ./arch/x86/include/asm/bitops.h:311 >> RIP [< inline >] kvm_lapic_latched_init arch/x86/kvm/lapic.h:164 >> RIP [< inline >] kvm_vcpu_ioctl_x86_get_vcpu_events >> arch/x86/kvm/x86.c:2936 >> RIP [<ffffffff81057171>] kvm_arch_vcpu_ioctl+0xa31/0x2ef0 >> arch/x86/kvm/x86.c:3347 >> RSP <ffff880062e37900> >> ---[ end trace 16449377928e034b ]--- >> >> >> or: >> >> kasan: GPF could be caused by NULL-ptr deref or user memory >> accessgeneral protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN >> Modules linked in: >> CPU: 0 PID: 9555 Comm: syz-executor Not tainted 4.4.0-rc8+ #217 >> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 >> task: ffff88006301de00 ti: ffff880062568000 task.ti: ffff880062568000 >> RIP: 0010:[<ffffffff810cf5ab>] [<ffffffff810cf5ab>] >> wait_lapic_expire+0x6b/0x560 >> RSP: 0018:ffff88006256fa48 EFLAGS: 00010006 >> RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff88006301e5c8 >> RDX: 0000000000000011 RSI: 0000000000000000 RDI: ffff880033590360 >> RBP: ffff88006256fa88 R08: 0000000000000001 R09: 0000000000000002 >> R10: 0000000000000001 R11: 0000000000000001 R12: ffff880033590000 >> R13: ffff880033590030 R14: 0000000000000088 R15: ffff88003359002c >> FS: 00007f4809354700(0000) GS:ffff88003ec00000(0000) knlGS:0000000000000000 >> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >> CR2: 00007f4808b53000 CR3: 0000000033f3f000 CR4: 00000000000026f0 >> Stack: >> ffff88006256fa70 0000000000000082 0000000000000003 ffff88006301de00 >> ffff880033590030 ffff880033590030 ffff880033590000 ffff88003359002c >> ffff88006256fc10 ffffffff8106a1dc ffffffff8106a75b 0000000000013210 >> Call Trace: >> [< inline >] vcpu_enter_guest arch/x86/kvm/x86.c:6523 >> [< inline >] vcpu_run arch/x86/kvm/x86.c:6660 >> [<ffffffff8106a1dc>] kvm_arch_vcpu_ioctl_run+0x25ec/0x5820 >> arch/x86/kvm/x86.c:6818 >> [<ffffffff8101cf61>] kvm_vcpu_ioctl+0x5f1/0xd00 >> arch/x86/kvm/../../../virt/kvm/kvm_main.c:2375 >> [< inline >] vfs_ioctl fs/ioctl.c:43 >> [<ffffffff817b36b1>] do_vfs_ioctl+0x681/0xe40 fs/ioctl.c:607 >> [< inline >] SYSC_ioctl fs/ioctl.c:622 >> [<ffffffff817b3eff>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:613 >> [<ffffffff85e745b6>] entry_SYSCALL_64_fastpath+0x16/0x7a >> arch/x86/entry/entry_64.S:185 >> Code: 60 03 00 00 0f 1f 44 00 00 e8 92 07 49 00 4c 8d b3 88 00 00 00 >> e8 86 07 49 00 4c 89 f2 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> >> 3c 02 00 0f 85 d8 04 00 00 4c 8b ab 88 00 00 00 4d 85 ed 75 >> RIP [<ffffffff810cf5ab>] wait_lapic_expire+0x6b/0x560 arch/x86/kvm/lapic.c:1245 >> RSP <ffff88006256fa48> >> ---[ end trace 560c2b85e36670bc ]--- >> >> or: >> >> kasan: GPF could be caused by NULL-ptr deref or user memory >> accessgeneral protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN >> Modules linked in: >> CPU: 3 PID: 11264 Comm: syz-executor Not tainted 4.4.0-rc8+ #217 >> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 >> task: ffff880064d55e00 ti: ffff880064dc0000 task.ti: ffff880064dc0000 >> RIP: 0010:[<ffffffff810d138d>] [<ffffffff810d138d>] >> apic_has_pending_timer+0x7d/0x210 >> RSP: 0018:ffff880064dc7a60 EFLAGS: 00010206 >> RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000004 >> RDX: 0000000000000017 RSI: 0000000000000000 RDI: 00000000000000b8 >> RBP: ffff880064dc7a70 R08: 0000000000000002 R09: 0000000000000001 >> R10: ffff880064d55e00 R11: ffff880063528220 R12: ffff880063250030 >> R13: ffff880063250030 R14: ffff880063250000 R15: 0000000000000000 >> FS: 00007fb05f305700(0000) GS:ffff88006d700000(0000) knlGS:0000000000000000 >> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >> CR2: 00000000006d7760 CR3: 0000000065ae9000 CR4: 00000000000026e0 >> Stack: >> ffff880063250000 ffff880063250030 ffff880064dc7a88 ffffffff810c7af5 >> ffffffff86fee5c0 ffff880064dc7c10 ffffffff810685d4 ffffffff8106a75b >> 0000000000013210 ffff880065a35000 1ffff1000c9b8f59 ffff880064dc0008 >> Call Trace: >> [<ffffffff810c7af5>] kvm_cpu_has_pending_timer+0x15/0x20 arch/x86/kvm/irq.c:36 >> [< inline >] vcpu_run arch/x86/kvm/x86.c:6669 >> [<ffffffff810685d4>] kvm_arch_vcpu_ioctl_run+0x9e4/0x5820 >> arch/x86/kvm/x86.c:6818 >> [<ffffffff8101cf61>] kvm_vcpu_ioctl+0x5f1/0xd00 >> arch/x86/kvm/../../../virt/kvm/kvm_main.c:2375 >> [< inline >] vfs_ioctl fs/ioctl.c:43 >> [<ffffffff817b36b1>] do_vfs_ioctl+0x681/0xe40 fs/ioctl.c:607 >> [< inline >] SYSC_ioctl fs/ioctl.c:622 >> [<ffffffff817b3eff>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:613 >> [<ffffffff85e745b6>] entry_SYSCALL_64_fastpath+0x16/0x7a >> arch/x86/entry/entry_64.S:185 >> Code: ba e9 48 00 0f 1f 44 00 00 e8 b0 e9 48 00 e8 ab e9 48 00 48 8d >> bb b8 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> >> 3c 02 00 0f 85 46 01 00 00 4c 8b a3 b8 00 00 00 48 b8 00 00 >> RIP [< inline >] arch_static_branch >> ./arch/x86/include/asm/jump_label.h:21 >> RIP [< inline >] static_key_false include/linux/jump_label.h:133 >> RIP [< inline >] kvm_apic_hw_enabled arch/x86/kvm/lapic.h:117 >> RIP [< inline >] apic_enabled arch/x86/kvm/lapic.c:121 >> RIP [<ffffffff810d138d>] apic_has_pending_timer+0x7d/0x210 >> arch/x86/kvm/lapic.c:1731 >> RSP <ffff880064dc7a60> >> ---[ end trace fe9c10b88e48c946 ]--- >> >> >> All crashes suggest that apic is NULL. >> >> On commit b06f3a168cdcd80026276898fd1fee443ef25743 (Jan 6). Ping. Just hit it again on 67016f6cdfd079e632bbc49e33178b2d558c120a (Jun 20): general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN Modules linked in: CPU: 1 PID: 12583 Comm: syz-executor Not tainted 4.7.0-rc4+ #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 task: ffff8800355d46c0 ti: ffff880034198000 task.ti: ffff880034198000 RIP: 0010:[<ffffffff811260ba>] [<ffffffff811260ba>] wait_lapic_expire+0x6a/0x5e0 RSP: 0018:ffff88003419fa40 EFLAGS: 00010002 RAX: dffffc0000000000 RBX: ffff880033cf0040 RCX: ffffc900020e4000 RDX: 0000000000000010 RSI: 1ffff10006833001 RDI: ffff880033cf03a0 RBP: ffff88003419fa78 R08: 0000000000000001 R09: 0000000000000002 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: ffff880033cf0070 R14: 0000000000000080 R15: ffff880033cf0040 FS: 00007fd1bdd14700(0000) GS:ffff88003ed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd1bdcf3000 CR3: 0000000061716000 CR4: 00000000000026e0 Stack: 0000000000000086 0000000000000003 ffff880033cf0070 00000000ffffffff ffff880033cf0070 ffff880033cf006c ffff880033cf0040 ffff88003419fc10 ffffffff810bee70 ffffffff810bf48f ffffffff81478fa0 ffff8800355d46c0 Call Trace: [< inline >] vcpu_enter_guest arch/x86/kvm/x86.c:6638 [< inline >] vcpu_run arch/x86/kvm/x86.c:6777 [<ffffffff810bee70>] kvm_arch_vcpu_ioctl_run+0x2490/0x5f60 arch/x86/kvm/x86.c:6935 [<ffffffff8106841e>] kvm_vcpu_ioctl+0x61e/0xe70 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2457 [< inline >] vfs_ioctl fs/ioctl.c:43 [<ffffffff818510bc>] do_vfs_ioctl+0x18c/0xff0 fs/ioctl.c:674 [< inline >] SYSC_ioctl fs/ioctl.c:689 [<ffffffff81851faf>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:680 [<ffffffff86a97000>] entry_SYSCALL_64_fastpath+0x23/0xc1 arch/x86/entry/entry_64.S:207 Code: 03 00 00 0f 1f 44 00 00 e8 54 04 47 00 4d 8d b4 24 80 00 00 00 e8 47 04 47 00 4c 89 f2 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 58 05 00 00 4d 8b ac 24 80 00 00 00 4d 85 ed RIP [<ffffffff811260ba>] wait_lapic_expire+0x6a/0x5e0 arch/x86/kvm/lapic.c:1300 RSP <ffff88003419fa40> ---[ end trace dc1986f78b27e282 ]--- -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html