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: 5897 at arch/x86/kvm/vmx/vmx.c:2610 free_loaded_vmcs+0x114/0x160 arch/x86/kvm/vmx/vmx.c:2606
Modules linked in:
CPU: 0 PID: 5897 Comm: syz-executor873 Not tainted 5.11.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:free_loaded_vmcs arch/x86/kvm/vmx/vmx.c:2610 [inline]
RIP: 0010:free_loaded_vmcs+0x114/0x160 arch/x86/kvm/vmx/vmx.c:2601
Code: c7 c6 a0 fd 19 81 e8 7b ec 43 00 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 75 3e 48 8b 2b e9 49 ff ff ff <0f> 0b eb c6 e8 23 01 87 00 e9 2f ff ff ff e8 29 01 87 00 e9 f4 fe
RSP: 0018:ffffc9000194f9e0 EFLAGS: 00010286
RAX: dffffc0000000000 RBX: ffff8880151764d0 RCX: 1ffffffff1865e19
RDX: 1ffff11002a2ec9b RSI: ffffffff888afa60 RDI: ffff8880151764d8
RBP: ffff88802ce7b000 R08: 0000000000000001 R09: 0000000000000001
R10: fffffbfff1cce29c R11: 0000000000000001 R12: ffffc900016919e8
R13: 0000000000000003 R14: fffff520002d233d R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055a78fa8c300 CR3: 0000000021bf0000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 kvm_arch_vcpu_destroy+0xd0/0x3f0 arch/x86/kvm/x86.c:10081
 kvm_vcpu_destroy+0x18/0xa0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:421
 kvm_free_vcpus arch/x86/kvm/x86.c:10437 [inline]
 kvm_arch_destroy_vm+0x2a5/0x5f0 arch/x86/kvm/x86.c:10560
 kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:878 [inline]
 kvm_put_kvm+0x48b/0xac0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:899
 kvm_vm_release+0x3a/0x60 arch/x86/kvm/../../../virt/kvm/kvm_main.c:922
 __fput+0x204/0x870 fs/file_table.c:280
 task_work_run+0xc0/0x160 kernel/task_work.c:140
 exit_task_work include/linux/task_work.h:30 [inline]
 do_exit+0xa81/0x2570 kernel/exit.c:825
 do_group_exit+0xe7/0x290 kernel/exit.c:922
 get_signal+0x36c/0x1c30 kernel/signal.c:2773
 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:811
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fde3fef2719
Code: Unable to access opcode bytes at RIP 0x7fde3fef26ef.
RSP: 002b:00007fde3fea2308 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007fde3ff7b408 RCX: 00007fde3fef2719
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fde3ff7b408
RBP: 00007fde3ff7b400 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fde3ff7b40c
R13: 00007fde3ff48098 R14: 6d766b2f7665642f R15: 0000000000022000