Hello, I've got the following crash while running syzkaller fuzzer: BUG: unable to handle kernel paging request at ffffc90005204408 IP: [< inline >] __read_once_size include/linux/compiler.h:243 IP: [< inline >] atomic_read arch/x86/include/asm/atomic.h:26 IP: [< inline >] search_memslots include/linux/kvm_host.h:900 IP: [< inline >] __gfn_to_memslot include/linux/kvm_host.h:928 IP: [< inline >] gfn_to_memslot arch/x86/kvm/../../../virt/kvm/kvm_main.c:1227 IP: [<ffffffff8105a299>] kvm_gfn_to_hva_cache_init+0x239/0x9f0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1951 PGD 3e90a067 [ 112.607074] PUD 6dc08067 Oops: 0000 [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 1 PID: 10437 Comm: syz-executor Not tainted 4.9.0-rc4+ #49 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 task: ffff88006b8b2dc0 task.stack: ffff88006d5f0000 RIP: 0010:[<ffffffff8105a299>] [< inline >] __read_once_size include/linux/compiler.h:243 RIP: 0010:[<ffffffff8105a299>] [< inline >] atomic_read arch/x86/include/asm/atomic.h:26 RIP: 0010:[<ffffffff8105a299>] [< inline >] search_memslots include/linux/kvm_host.h:900 RIP: 0010:[<ffffffff8105a299>] [< inline >] __gfn_to_memslot include/linux/kvm_host.h:928 RIP: 0010:[<ffffffff8105a299>] [< inline >] gfn_to_memslot arch/x86/kvm/../../../virt/kvm/kvm_main.c:1227 RIP: 0010:[<ffffffff8105a299>] [<ffffffff8105a299>] kvm_gfn_to_hva_cache_init+0x239/0x9f0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1951 RSP: 0018:ffff88006d5f7730 EFLAGS: 00010246 RAX: 0000000000000003 RBX: 0000000000000004 RCX: ffffc900013a5000 RDX: 0000000000000000 RSI: ffff88006de32d50 RDI: ffffc900051f9000 RBP: ffff88006d5f7808 R08: ffffed000dabef36 R09: ffffed000dabef36 R10: ffffed000dabef35 R11: ffff88006d5f79af R12: ffffffffffffff6e R13: ffff88006b290420 R14: 0000000000000001 R15: 0000000000000002 FS: 00007f6db05f1700(0000) GS:ffff88003ed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc90005204408 CR3: 000000003c36a000 CR4: 00000000000026e0 Stack: 1ffff1000dabeef0 ffff88006ba840c0 ffff88006d5f7750 ffffc90005204408 0000000000000001 ffff88006ba84000 0000000000000001 0000000000001000 ffff88006de32d50 ffffc900051f9000 0000000041b58ab3 ffffffff837c394f Call Trace: [<ffffffff8112696d>] kvm_lapic_set_vapic_addr+0xed/0x140 arch/x86/kvm/lapic.c:2217 [<ffffffff810a77e4>] kvm_arch_vcpu_ioctl+0x224/0x3100 arch/x86/kvm/x86.c:3425 [<ffffffff810608b2>] kvm_vcpu_ioctl+0x1e2/0xdd0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2708 [< inline >] vfs_ioctl fs/ioctl.c:43 [<ffffffff816b03cc>] do_vfs_ioctl+0x18c/0x1040 fs/ioctl.c:679 [< inline >] SYSC_ioctl fs/ioctl.c:694 [<ffffffff816b130f>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:685 [<ffffffff831f0dc1>] entry_SYSCALL_64_fastpath+0x1f/0xc2 Code: 03 48 b8 00 00 00 00 00 fc ff df 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 59 06 00 00 48 8b bd 70 ff ff ff <48> 63 87 08 b4 00 00 4c 8d 6f 08 48 8d 14 80 48 8d 04 50 49 8d RIP [< inline >] __read_once_size include/linux/compiler.h:243 RIP [< inline >] atomic_read arch/x86/include/asm/atomic.h:26 RIP [< inline >] search_memslots include/linux/kvm_host.h:900 RIP [< inline >] __gfn_to_memslot include/linux/kvm_host.h:928 RIP [< inline >] gfn_to_memslot arch/x86/kvm/../../../virt/kvm/kvm_main.c:1227 RIP [<ffffffff8105a299>] kvm_gfn_to_hva_cache_init+0x239/0x9f0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1951 RSP <ffff88006d5f7730> CR2: ffffc90005204408 ---[ end trace b42cbfdf0baf531e ]--- Kernel panic - not syncing: Fatal exception Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled reboot: cpu_has_vmx: ecx=80a02021 1 and another almost identical: BUG: unable to handle kernel paging request at ffffc90005907408 IP: [< inline >] __read_once_size include/linux/compiler.h:243 IP: [< inline >] atomic_read arch/x86/include/asm/atomic.h:26 IP: [< inline >] search_memslots include/linux/kvm_host.h:900 IP: [< inline >] __gfn_to_memslot include/linux/kvm_host.h:928 IP: [< inline >] gfn_to_memslot arch/x86/kvm/../../../virt/kvm/kvm_main.c:1227 IP: [<ffffffff8105a299>] kvm_gfn_to_hva_cache_init+0x239/0x9f0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1951 PGD 3e90a067 [ 2974.428060] PUD 6dc08067 Oops: 0000 [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 3 PID: 20506 Comm: syz-executor Not tainted 4.9.0-rc4+ #49 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 task: ffff880066c08040 task.stack: ffff8800665a8000 RIP: 0010:[<ffffffff8105a299>] [< inline >] __read_once_size include/linux/compiler.h:243 RIP: 0010:[<ffffffff8105a299>] [< inline >] atomic_read arch/x86/include/asm/atomic.h:26 RIP: 0010:[<ffffffff8105a299>] [< inline >] search_memslots include/linux/kvm_host.h:900 RIP: 0010:[<ffffffff8105a299>] [< inline >] __gfn_to_memslot include/linux/kvm_host.h:928 RIP: 0010:[<ffffffff8105a299>] [< inline >] gfn_to_memslot arch/x86/kvm/../../../virt/kvm/kvm_main.c:1227 RIP: 0010:[<ffffffff8105a299>] [<ffffffff8105a299>] kvm_gfn_to_hva_cache_init+0x239/0x9f0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1951 RSP: 0018:ffff8800665af730 EFLAGS: 00010246 RAX: 0000000000000003 RBX: 0000000000000004 RCX: ffffc90000b65000 RDX: 0000000000000000 RSI: ffff88006d85a3f0 RDI: ffffc900058fc000 RBP: ffff8800665af808 R08: ffffed000ccb5f36 R09: ffffed000ccb5f36 R10: ffffed000ccb5f35 R11: ffff8800665af9af R12: ffffffffffffff70 R13: ffff88006cf98420 R14: 0000000000000001 R15: 0000000000000003 FS: 00007f569fcf5700(0000) GS:ffff88006e300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc90005907408 CR3: 0000000069c4f000 CR4: 00000000000026e0 Stack: 1ffff1000ccb5ef0 ffff88006b1cc0c0 ffff8800665af750 ffffc90005907408 0000000000000001 ffff88006b1cc000 0000000000000001 0000000000001000 ffff88006d85a3f0 ffffc900058fc000 0000000041b58ab3 ffffffff837c394f Call Trace: [<ffffffff8112696d>] kvm_lapic_set_vapic_addr+0xed/0x140 arch/x86/kvm/lapic.c:2217 [<ffffffff810a77e4>] kvm_arch_vcpu_ioctl+0x224/0x3100 arch/x86/kvm/x86.c:3425 uhci_hcd 0000:00:01.2: BAR 4: can't reserve [io 0xc680-0xc69f] kvm_vm_ioctl_assign_device: Could not get access to device regions [<ffffffff810608b2>] kvm_vcpu_ioctl+0x1e2/0xdd0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2708 [< inline >] vfs_ioctl fs/ioctl.c:43 [<ffffffff816b03cc>] do_vfs_ioctl+0x18c/0x1040 fs/ioctl.c:679 uhci_hcd 0000:00:01.2: BAR 4: can't reserve [io 0xc680-0xc69f] kvm_vm_ioctl_assign_device: Could not get access to device regions [< inline >] SYSC_ioctl fs/ioctl.c:694 [<ffffffff816b130f>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:685 [<ffffffff831f0dc1>] entry_SYSCALL_64_fastpath+0x1f/0xc2 Code: 03 48 b8 00 00 00 00 00 fc ff df 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 59 06 00 00 48 8b bd 70 ff ff ff <48> 63 87 08 b4 00 00 4c 8d 6f 08 48 8d 14 80 48 8d 04 50 49 8d RIP [< inline >] __read_once_size include/linux/compiler.h:243 RIP [< inline >] atomic_read arch/x86/include/asm/atomic.h:26 RIP [< inline >] search_memslots include/linux/kvm_host.h:900 RIP [< inline >] __gfn_to_memslot include/linux/kvm_host.h:928 RIP [< inline >] gfn_to_memslot arch/x86/kvm/../../../virt/kvm/kvm_main.c:1227 RIP [<ffffffff8105a299>] kvm_gfn_to_hva_cache_init+0x239/0x9f0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1951 RSP <ffff8800665af730> CR2: ffffc90005907408 ---[ end trace 1382154a6662ad57 ]--- Kernel panic - not syncing: Fatal exception Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled reboot: cpu_has_vmx: ecx=80a02021 1 Also I've seen crashed in __gfn_to_hva_many on similar programs: BUG: unable to handle kernel paging request in __gfn_to_hva_many (but I don't have full reports for these) Unfortunately this is not reproducible. On commit 015ed9433be2b476ec7e2e6a9a411a56e3b5b035 (Nov 11). -- 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
