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: 1 PID: 5190 at arch/x86/kvm/lapic.c:2932 kvm_apic_accept_events+0x435/0x550 arch/x86/kvm/lapic.c:2932
Modules linked in:
CPU: 1 PID: 5190 Comm: syz.0.16 Not tainted 5.15.185-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:kvm_apic_accept_events+0x435/0x550 arch/x86/kvm/lapic.c:2932
Code: 00 00 00 65 48 8b 04 25 28 00 00 00 48 3b 44 24 60 75 1e 44 89 e0 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 fb a9 61 00 <0f> 0b e9 9d fd ff ff e8 7f 54 8b 08 89 d9 80 e1 07 80 c1 03 38 c1
RSP: 0018:ffffc900031cfb60 EFLAGS: 00010293
RAX: ffffffff81161825 RBX: 0000000000000002 RCX: ffff8880240bd940
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000002
RBP: ffffc900031cfc20 R08: dffffc0000000000 R09: fffffbfff1ff3640
R10: fffffbfff1ff3640 R11: 1ffffffff1ff363f R12: ffffc900031cfba0
R13: dffffc0000000000 R14: ffff888021294304 R15: ffff88807f5502e8
FS:  00007f596e4376c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005560025d9950 CR3: 0000000023789000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 vcpu_block arch/x86/kvm/x86.c:10116 [inline]
 vcpu_run arch/x86/kvm/x86.c:10164 [inline]
 kvm_arch_vcpu_ioctl_run+0xd46/0x1f40 arch/x86/kvm/x86.c:10399
 kvm_vcpu_ioctl+0x887/0xb80 virt/kvm/kvm_main.c:3894
 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: 0033:0x7f596f1c7929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f596e437038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f596f3eefa0 RCX: 00007f596f1c7929
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005
RBP: 00007f596f249b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f596f3eefa0 R15: 00007ffd0699ab98
 </TASK>