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 ]------------
WARNING: CPU: 1 PID: 4353 at arch/x86/kvm/vmx/vmx.c:1714 vmx_queue_exception+0x2b9/0x470 arch/x86/kvm/vmx/vmx.c:1714
Modules linked in:
CPU: 0 PID: 4353 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:vmx_queue_exception+0x2b9/0x470 arch/x86/kvm/vmx/vmx.c:1714
Code: 01 00 00 e8 69 70 58 00 eb 0c e8 62 70 58 00 eb 05 e8 5b 70 58 00 48 83 c4 18 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 47 70 58 00 <0f> 0b e9 a7 fe ff ff 89 f9 80 e1 07 38 c1 0f 8c 6e fd ff ff e8 1e
RSP: 0018:ffffc900031ef630 EFLAGS: 00010293
RAX: ffffffff81209f59 RBX: ffff88807ce80000 RCX: ffff88802c1e1dc0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff8d8b0eef R09: 1ffffffff1b161dd
R10: dffffc0000000000 R11: fffffbfff1b161de R12: ffff88807ce8270c
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000080000800
FS:  0000555583ba0500(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31124008 CR3: 000000001e998000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 inject_pending_event arch/x86/kvm/x86.c:9185 [inline]
 vcpu_enter_guest+0x836/0x6f70 arch/x86/kvm/x86.c:9908
 vcpu_run arch/x86/kvm/x86.c:10192 [inline]
 kvm_arch_vcpu_ioctl_run+0x804/0x1e40 arch/x86/kvm/x86.c:10432
 kvm_vcpu_ioctl+0x8f2/0xc10 virt/kvm/kvm_main.c:3895
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f56aca19159
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff93babf28 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f56acca0fa0 RCX: 00007f56aca19159
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005
RBP: 00007f56acab0024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f56acca0fac R14: 00007f56acca0fa0 R15: 00007f56acca0fa0
 </TASK>