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.
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WARNING: CPU: 0 PID: 3537 at arch/x86/kvm/vmx/vmx.c:5163 handle_exception_nmi+0x8f2/0xe10
Modules linked in:
CPU: 0 PID: 3537 Comm: syz-executor273 Not tainted 6.1.34-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
RIP: 0010:handle_exception_nmi+0x8f2/0xe10 arch/x86/kvm/vmx/vmx.c:5163
Code: c4 df 65 00 0f 0b e9 44 f9 ff ff 89 f9 80 e1 07 80 c1 03 38 c1 0f 8c 7c f7 ff ff e8 98 28 bc 00 e9 72 f7 ff ff e8 9e df 65 00 <0f> 0b e9 53 fc ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 9d f8 ff
RSP: 0018:ffffc90003aef490 EFLAGS: 00010293
RAX: ffffffff8123f5b2 RBX: ffff88807bf48000 RCX: ffff888027bb9dc0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff8123f1ff R09: ffffed100f7e904a
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff1100f7e901b
R13: 0000000000000000 R14: 00000000009d23e2 R15: dffffc0000000000
FS:  00005555566b1300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffaa101fe4 CR3: 0000000078aa3000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __vmx_handle_exit arch/x86/kvm/vmx/vmx.c:6480 [inline]
 vmx_handle_exit+0xca0/0x1a00 arch/x86/kvm/vmx/vmx.c:6497
 vcpu_enter_guest+0x2ad0/0xa570 arch/x86/kvm/x86.c:10920
 vcpu_run arch/x86/kvm/x86.c:11023 [inline]
 kvm_arch_vcpu_ioctl_run+0xf5f/0x20c0 arch/x86/kvm/x86.c:11244
 kvm_vcpu_ioctl+0x7f0/0xcf0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:4091
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fb6375843f9
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd9d1c0748 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb6375843f9
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000006
RBP: 00007fb637547ef0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000009120 R11: 0000000000000246 R12: 00007fb637547f80
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>