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.
loop0: detected capacity change from 0 to 1024
------------[ cut here ]------------
WARNING: CPU: 0 PID: 4165 at arch/x86/kvm/x86.c:10346 kvm_arch_vcpu_ioctl_run+0x1d63/0x1f80
Modules linked in:
CPU: 0 PID: 4165 Comm: syz-executor399 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:kvm_arch_vcpu_ioctl_run+0x1d63/0x1f80 arch/x86/kvm/x86.c:10346
Code: df e8 d1 c8 ba 00 e9 e5 fa ff ff 89 d9 80 e1 07 38 c1 0f 8c 26 fb ff ff 48 89 df e8 b7 c8 ba 00 e9 19 fb ff ff e8 7d e0 70 00 <0f> 0b e9 e0 fb ff ff 89 d9 80 e1 07 38 c1 0f 8c 63 fb ff ff 48 89
RSP: 0018:ffffc90002567c60 EFLAGS: 00010293
RAX: ffffffff810fa513 RBX: 0000000000000000 RCX: ffff888022e19dc0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: dffffc0000000000 R08: ffffffff8116c302 R09: fffffbfff1c150ee
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888022e19dc0
R13: ffff88807869c000 R14: ffff88807869c0f0 R15: ffff88806f497000
FS:  0000555585f0d380(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556f6dd44198 CR3: 000000006f468000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 kvm_vcpu_ioctl+0x7f0/0xcf0 virt/kvm/kvm_main.c:3894
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f0d282eeaf9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd7675a988 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000400000000140 RCX: 00007f0d282eeaf9
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005
RBP: 00007f0d28362610 R08: 00007ffd7675ab58 R09: 00007ffd7675ab58
R10: 0000000000000705 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffd7675ab48 R14: 0000000000000001 R15: 0000000000000001
 </TASK>