On Tue, Oct 31, 2017 at 2:10 PM, Wanpeng Li <kernellwp@xxxxxxxxx> wrote: > 2017-10-31 17:59 GMT+08:00 Dmitry Vyukov <dvyukov@xxxxxxxxxx>: >> Hello, >> >> I am seeing the following crash on upstream >> 15f859ae5c43c7f0a064ed92d33f7a5bc5de6de0 (Oct 26). >> Reproducer: >> https://gist.githubusercontent.com/dvyukov/a9690f90c39c1e3b1b6c7acda2d5ef89/raw/33e07f3d6779005fc475764e0802e4a5aee8d0cf/gistfile1.txt >> I run qemu with -append "kvm-intel.nested=1" -enable-kvm -cpu host. My >> host cpu is E5-2690. >> > > I can't reproduce this w/ latest kvm/queue in both L0 and L1. In > addition, there is a commit tries to fix cr4 recently. > https://git.kernel.org/pub/scm/virt/kvm/kvm.git/commit/?id=8eb3f87d903168bdbd1222776a6b1e281f50513e > The testcast is complex, if the below strace log is as you expected? I have that commit in my tree. I did a little testing and if I remove "-cpu host" from qemu command line, then crash does not happen. So my E5-2690 is somehow involved. The test case is actually for a different issues, but since recently lots of kvm-related programs trigger this bug for me. And it seems to be very easy to trigger. Here is my strace output: root@syzkaller:~# strace ./a.out execve("./a.out", ["./a.out"], [/* 11 vars */]) = 0 uname({sys="Linux", node="syzkaller", ...}) = 0 brk(0) = 0xe3c000 brk(0xe3d1c0) = 0xe3d1c0 arch_prctl(ARCH_SET_FS, 0xe3c880) = 0 readlink("/proc/self/exe", "/root/a.out", 4096) = 11 brk(0xe5e1c0) = 0xe5e1c0 brk(0xe5f000) = 0xe5f000 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory) mmap(0x20000000, 11481088, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x20000000 openat(AT_FDCWD, "/dev/kvm", O_WRONLY) = 3 ioctl(3, KVM_CREATE_VM , 0) = 4 ioctl(4, KVM_CREATE_VCPU, 0) = 5 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c07f0) = 0 ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7ffcf97c0630) = 0 ioctl(5, KVM_GET_SREGS, 0x7ffcf97c07f0) = 0 open("/dev/kvm", O_RDWR) = 6 ioctl(6, KVM_GET_SUPPORTED_CPUID, 0x7ffcf97c0930) = 0 ioctl(5, KVM_SET_CPUID2, 0x7ffcf97c0930) = 0 close(6) = 0 ioctl(5, KVM_SET_MSRS, 0x7ffcf97c00f0) = 5 ioctl(5, KVM_SET_SREGS, 0x7ffcf97c07f0) = 0 ioctl(5, KVM_SET_REGS, 0x7ffcf97c0760) = 0 mremap(0x20998000, 4096, 16384, MREMAP_MAYMOVE|MREMAP_FIXED, 0x200fa000) = 0x200fa000 ioctl(5, KVM_RUN, 0) = 0 mbind(0x20000000, 8192, MPOL_DEFAULT, 0x20001ff8, 2, MPOL_MF_MOVE) = 0 exit_group(0) = ? [ 44.908130] kasan: CONFIG_KASAN_INLINE enabled [ 44.909140] kasan: GPF could be caused by NULL-ptr deref or user memory access [ 44.910615] general protection fault: 0000 [#1] SMP KASAN [ 44.911654] Modules linked in: [ 44.912241] CPU: 2 PID: 3074 Comm: a.out Not tainted 4.14.0-rc6+ #12 [ 44.913556] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 [ 44.915146] task: ffff88006a8e0740 task.stack: ffff88006bab8000 [ 44.916387] RIP: 0010:native_write_cr4+0x4/0x10 [ 44.917324] RSP: 0018:ffff88006babf458 EFLAGS: 00010097 [ 44.918373] RAX: ffff88006a8e0740 RBX: 00000000001606e0 RCX: 0000000000000000 [ 44.919693] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000001606e0 [ 44.921049] RBP: ffff88006babf458 R08: ffffffff8106cf91 R09: 0000000000000000 [ 44.922417] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000002 [ 44.923738] R13: ffff88006cb14828 R14: ffff88006cb14850 R15: ffff88006cb00000 [ 44.925061] FS: 0000000000e3c880(0000) GS:ffff88006cb00000(0000) knlGS:0000000000000000 [ 44.926652] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 44.927727] CR2: 0000000000000000 CR3: 0000000005a22004 CR4: 00000000001626e0 [ 44.929067] Call Trace: [ 44.929627] hardware_disable+0x17f/0x210 [ 44.930373] ? kvm_io_bus_get_dev+0x2a0/0x2a0 [ 44.931148] kvm_arch_hardware_disable+0x35/0xd0 [ 44.932022] ? kvm_io_bus_get_dev+0x2a0/0x2a0 [ 44.932827] hardware_disable_nolock+0x30/0x40 [ 44.933591] on_each_cpu+0xca/0x1b0 [ 44.934283] hardware_disable_all_nolock+0x3e/0x50 [ 44.935168] kvm_put_kvm+0x956/0xdf0 [ 44.935781] ? kvm_clear_guest+0xb0/0xb0 [ 44.936543] ? kvm_irqfd_release+0xd1/0x120 [ 44.937360] ? lock_downgrade+0x990/0x990 [ 44.938162] ? _raw_spin_unlock_irq+0x27/0x70 [ 44.938903] ? kvm_irqfd_release+0xdd/0x120 [ 44.939676] ? kvm_irqfd_release+0xdd/0x120 [ 44.940459] ? kvm_put_kvm+0xdf0/0xdf0 [ 44.941092] kvm_vm_release+0x42/0x50 [ 44.941804] __fput+0x327/0x7e0 [ 44.942447] ? fput+0x140/0x140 [ 44.942966] ? check_same_owner+0x320/0x320 [ 44.943738] ? _raw_spin_unlock_irq+0x27/0x70 [ 44.944435] ____fput+0x15/0x20 [ 44.945026] task_work_run+0x199/0x270 [ 44.945734] ? task_work_cancel+0x210/0x210 [ 44.946406] ? _raw_spin_unlock+0x22/0x30 [ 44.947114] ? switch_task_namespaces+0x87/0xc0 [ 44.947927] do_exit+0x9b5/0x1ad0 [ 44.948463] ? lock_acquire+0x1d5/0x580 [ 44.949149] ? lock_acquire+0x1d5/0x580 [ 44.949776] ? mm_update_next_owner+0x930/0x930 [ 44.950577] ? lock_release+0xa40/0xa40 [ 44.951220] ? check_same_owner+0x320/0x320 [ 44.951906] ? check_noncircular+0x20/0x20 [ 44.952622] ? _raw_spin_unlock_irq+0x27/0x70 [ 44.953402] ? recalc_sigpending_tsk+0x117/0x150 [ 44.954328] ? ptrace_stop+0x631/0xa40 [ 44.954916] ? find_held_lock+0x35/0x1d0 [ 44.955617] ? ptrace_notify+0xee/0x130 [ 44.956208] ? lock_downgrade+0x990/0x990 [ 44.956862] ? do_raw_spin_trylock+0x190/0x190 [ 44.957615] ? _raw_spin_unlock_irq+0x27/0x70 [ 44.958300] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 44.959100] ? trace_hardirqs_on+0xd/0x10 [ 44.959794] ? _raw_spin_unlock_irq+0x27/0x70 [ 44.960512] ? ptrace_notify+0xee/0x130 [ 44.961106] ? syscall_trace_enter+0x5d4/0x1290 [ 44.961850] ? trace_raw_output_sys_exit+0x100/0x100 [ 44.962624] ? exit_to_usermode_loop+0x8c/0x310 [ 44.963328] do_group_exit+0x149/0x400 [ 44.963977] ? trace_hardirqs_off+0xd/0x10 [ 44.964590] ? exit_to_usermode_loop+0x198/0x310 [ 44.965363] ? SyS_exit+0x30/0x30 [ 44.965963] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 44.966742] ? do_syscall_64+0xb6/0x8d0 [ 44.967376] ? do_group_exit+0x400/0x400 [ 44.968026] SyS_exit_group+0x1d/0x20 [ 44.968568] do_syscall_64+0x26c/0x8d0 [ 44.969198] ? kill_pid+0x30/0x30 [ 44.969703] ? syscall_return_slowpath+0x510/0x510 [ 44.970471] ? syscall_return_slowpath+0x2b3/0x510 [ 44.971196] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 44.971924] ? return_from_SYSCALL_64+0x2d/0x7a [ 44.972665] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 44.973473] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 44.974156] entry_SYSCALL64_slow_path+0x25/0x25 [ 44.974890] RIP: 0033:0x443849 [ 44.975331] RSP: 002b:00007ffcf97c1d48 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 44.976464] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000443849 [ 44.977551] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 44.978646] RBP: 00000000004b5e88 R08: 000000000000003c R09: 00000000000000e7 [ 44.979696] R10: ffffffffffffffc0 R11: 0000000000000246 R12: 0000000000000001 [ 44.980755] R13: 00000000006c52c0 R14: 0000000000404890 R15: 0000000000000000 [ 44.981825] Code: 0f 1f 80 00 00 00 00 55 48 89 e5 0f 20 d8 5d c3 0f 1f 80 00 00 00 00 55 48 89 e5 0f 22 df 5d c3 0f 1f 80 00 00 00 00 55 48 89 e5 <0f> 22 e7 5d c3 0f 1f 80 00 00 00 00 55 48 89 e5 44 0f 20 c0 5d [ 44.984645] RIP: native_write_cr4+0x4/0x10 RSP: ffff88006babf458 [ 44.985583] ---[ end trace 45dae0ba7fdb5e5f ]--- > execve("./a.out", ["./a.out"], [/* 32 vars */]) = 0 > uname({sysname="Linux", nodename="kernel", ...}) = 0 > brk(NULL) = 0x1d42000 > brk(0x1d431c0) = 0x1d431c0 > arch_prctl(ARCH_SET_FS, 0x1d42880) = 0 > readlink("/proc/self/exe", "/home/kernel/a.out", 4096) = 18 > brk(0x1d641c0) = 0x1d641c0 > brk(0x1d65000) = 0x1d65000 > access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory) > mmap(0x20000000, 11481088, PROT_READ|PROT_WRITE, > MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x20000000 > openat(AT_FDCWD, "/dev/kvm", O_WRONLY) = 3 > ioctl(3, KVM_CREATE_VM or LOGGER_GET_LOG_BUF_SIZE, 0) = 4 > ioctl(4, KVM_CREATE_VCPU, 0) = 5 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1230) = 0 > ioctl(4, KVM_SET_USER_MEMORY_REGION, 0x7fff5e6c1170) = 0 > ioctl(5, KVM_GET_SREGS, 0x7fff5e6c1330) = 0 > open("/dev/kvm", O_RDWR) = 6 > ioctl(6, KVM_GET_SUPPORTED_CPUID, 0x7fff5e6c1470) = 0 > ioctl(5, KVM_SET_CPUID2, 0x7fff5e6c1470) = 0 > close(6) = 0 > ioctl(5, KVM_SET_MSRS, 0x7fff5e6c0c30) = 5 > ioctl(5, KVM_SET_SREGS, 0x7fff5e6c1330) = 0 > ioctl(5, KVM_SET_REGS, 0x7fff5e6c1230) = 0 > mremap(0x20998000, 4096, 16384, MREMAP_MAYMOVE|MREMAP_FIXED, > 0x200fa000) = 0x200fa000 > ioctl(5, KVM_RUN, 0) = 0 > mbind(0x20000000, 8192, MPOL_DEFAULT 0x20001ff8, 2, MPOL_MF_MOVE) = 0 > exit_group(0) = ? > +++ exited with 0 +++ > i > > Regards, > Wanpeng Li > >> general protection fault: 0000 [#1] SMP KASAN >> Modules linked in: >> CPU: 1 PID: 3064 Comm: a.out Not tainted 4.14.0-rc6+ #11 >> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 >> task: ffff880064c203c0 task.stack: ffff880066718000 >> RIP: 0010:native_write_cr4+0x4/0x10 arch/x86/include/asm/special_insns.h:75 >> RSP: 0018:ffff88006671f598 EFLAGS: 00010097 >> RAX: ffff880064c203c0 RBX: 00000000001606e0 RCX: 0000000000000000 >> RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000001606e0 >> RBP: ffff88006671f598 R08: 0000000000000006 R09: 0000000000000006 >> R10: ffff880064c203c0 R11: 0000000000000000 R12: 0000000000000001 >> R13: ffff88006ca94828 R14: ffff88006ca94850 R15: ffff88006ca80000 >> FS: 00000000019cd880(0000) GS:ffff88006ca80000(0000) knlGS:0000000000000000 >> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >> CR2: 0000000000000000 CR3: 0000000005a22001 CR4: 00000000001626e0 >> Call Trace: >> __write_cr4 arch/x86/include/asm/paravirt.h:76 [inline] >> cr4_clear_bits arch/x86/include/asm/tlbflush.h:197 [inline] >> kvm_cpu_vmxoff arch/x86/kvm/vmx.c:3571 [inline] >> hardware_disable+0x197/0x210 arch/x86/kvm/vmx.c:3577 >> kvm_arch_hardware_disable+0x35/0xd0 arch/x86/kvm/x86.c:7920 >> hardware_disable_nolock+0x30/0x40 >> arch/x86/kvm/../../../virt/kvm/kvm_main.c:3282 >> on_each_cpu+0xca/0x1b0 kernel/smp.c:604 >> hardware_disable_all_nolock+0x44/0x60 >> arch/x86/kvm/../../../virt/kvm/kvm_main.c:3300 >> hardware_disable_all arch/x86/kvm/../../../virt/kvm/kvm_main.c:3306 [inline] >> kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:735 [inline] >> kvm_put_kvm+0x887/0xe00 arch/x86/kvm/../../../virt/kvm/kvm_main.c:748 >> kvm_vm_release+0x42/0x50 arch/x86/kvm/../../../virt/kvm/kvm_main.c:759 >> __fput+0x301/0x7e0 fs/file_table.c:210 >> ____fput+0x15/0x20 fs/file_table.c:244 >> task_work_run+0x19e/0x250 kernel/task_work.c:112 >> exit_task_work include/linux/task_work.h:21 [inline] >> do_exit+0x99f/0x18b0 kernel/exit.c:865 >> do_group_exit+0x14b/0x3f0 kernel/exit.c:968 >> SYSC_exit_group kernel/exit.c:979 [inline] >> SyS_exit_group+0x1d/0x20 kernel/exit.c:977 >> entry_SYSCALL_64_fastpath+0x1f/0xbe >> RIP: 0033:0x443849 >> RSP: 002b:00007ffe58a95c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 >> RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000443849 >> RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 >> RBP: 0000000000000086 R08: 000000000000003c R09: 00000000000000e7 >> R10: ffffffffffffffc0 R11: 0000000000000246 R12: 0000000000000000 >> R13: 0000000000404800 R14: 0000000000404890 R15: 0000000000000000 >> Code: 0f 1f 80 00 00 00 00 55 48 89 e5 0f 20 d8 5d c3 0f 1f 80 00 00 >> 00 00 55 48 89 e5 0f 22 df 5d c3 0f 1f 80 00 00 00 00 55 48 89 e5 <0f> >> 22 e7 5d c3 0f 1f 80 00 00 00 00 55 48 89 e5 44 0f 20 c0 5d >> RIP: native_write_cr4+0x4/0x10 arch/x86/include/asm/special_insns.h:75 >> RSP: ffff88006671f598 >> ---[ end trace 6f9dbcc14aa47936 ]---
