L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details. ------------[ cut here ]------------ kernel BUG at arch/x86/kvm/mmu/mmu.c:3416! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 9377 Comm: syz-executor731 Not tainted 5.5.0-rc2-next-20191220-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:transparent_hugepage_adjust+0x4c8/0x550 arch/x86/kvm/mmu/mmu.c:3416 Code: ff ff e8 5b 84 5e 00 48 8b 45 b8 48 83 e8 01 48 89 45 c8 e9 a3 fd ff ff 48 89 df e8 e2 6e 9c 00 e9 7b fb ff ff e8 38 84 5e 00 <0f> 0b 48 8b 7d c8 e8 cd 6e 9c 00 e9 ba fc ff ff 49 8d 7f 30 e8 9f RSP: 0018:ffffc900020577f8 EFLAGS: 00010293 RAX: ffff88808e60e180 RBX: ffffc900020578e8 RCX: ffffffff8116d017 RDX: 0000000000000000 RSI: ffffffff8116d158 RDI: 0000000000000007 RBP: ffffc90002057840 R08: ffff88808e60e180 R09: ffffed1011639682 R10: ffffed1011639681 R11: ffff88808b1cb40b R12: 00000000000001b3 R13: 000000000009abb3 R14: 000000000009abb1 R15: 0000000000000000 FS: 0000000001e6d880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000a786c000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: tdp_page_fault+0x580/0x6a0 arch/x86/kvm/mmu/mmu.c:4315 kvm_mmu_page_fault+0x1dd/0x1800 arch/x86/kvm/mmu/mmu.c:5539 handle_ept_violation+0x259/0x560 arch/x86/kvm/vmx/vmx.c:5163 vmx_handle_exit+0x29f/0x1730 arch/x86/kvm/vmx/vmx.c:5921 vcpu_enter_guest+0x3354/0x6110 arch/x86/kvm/x86.c:8290 vcpu_run arch/x86/kvm/x86.c:8354 [inline] kvm_arch_vcpu_ioctl_run+0x430/0x17b0 arch/x86/kvm/x86.c:8561 kvm_vcpu_ioctl+0x4dc/0xfc0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2847 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x123/0x180 fs/ioctl.c:747 __do_sys_ioctl fs/ioctl.c:756 [inline] __se_sys_ioctl fs/ioctl.c:754 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:754 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x440359 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fff5e6529c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440359 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000006 RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 R10: 00000000004002c8 R11: 0000000000000246 R12: 0000000000401be0 R13: 0000000000401c70 R14: 0000000000000000 R15: 0000000000000000 Modules linked in: ---[ end trace b8e2ee2ce3d38386 ]--- RIP: 0010:transparent_hugepage_adjust+0x4c8/0x550 arch/x86/kvm/mmu/mmu.c:3416 Code: ff ff e8 5b 84 5e 00 48 8b 45 b8 48 83 e8 01 48 89 45 c8 e9 a3 fd ff ff 48 89 df e8 e2 6e 9c 00 e9 7b fb ff ff e8 38 84 5e 00 <0f> 0b 48 8b 7d c8 e8 cd 6e 9c 00 e9 ba fc ff ff 49 8d 7f 30 e8 9f RSP: 0018:ffffc900020577f8 EFLAGS: 00010293 RAX: ffff88808e60e180 RBX: ffffc900020578e8 RCX: ffffffff8116d017 RDX: 0000000000000000 RSI: ffffffff8116d158 RDI: 0000000000000007 RBP: ffffc90002057840 R08: ffff88808e60e180 R09: ffffed1011639682 R10: ffffed1011639681 R11: ffff88808b1cb40b R12: 00000000000001b3 R13: 000000000009abb3 R14: 000000000009abb1 R15: 0000000000000000 FS: 0000000001e6d880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000a786c000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400