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.
kvm: emulating exchange as write
BUG: kernel NULL pointer dereference, address: 0000000000000086
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 1f04ee067 P4D 1f04ee067 PUD 1f04a5067 PMD 0 
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 390 Comm: syz.4.5 Not tainted 5.4.276-syzkaller-00021-g58de09405d1e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
RIP: 0010:0x86
Code: Bad RIP value.
RSP: 0018:ffff8881d9607308 EFLAGS: 00010086
RAX: ffff8881d9607338 RBX: dffffc0000000000 RCX: 0000000000040000
RDX: ffffc90001749000 RSI: 0000000000032f84 RDI: 0000000000032f85
RBP: 0000000000000fd0 R08: ffffffff82316961 R09: ffffffff811c8ff5
R10: ffff8881f30c2f40 R11: 0000000000000002 R12: ffffffff846015d0
R13: fffffe0000000fd8 R14: ffff8881efb50000 R15: fffffe0000000fdb
FS:  00007fdd255796c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000005c CR3: 00000001f0e84000 CR4: 00000000003426b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
Modules linked in:
CR2: 0000000000000086
---[ end trace 142bdc5fa88d92e6 ]---
RIP: 0010:0x86
Code: Bad RIP value.
RSP: 0018:ffff8881d9607308 EFLAGS: 00010086
RAX: ffff8881d9607338 RBX: dffffc0000000000 RCX: 0000000000040000
RDX: ffffc90001749000 RSI: 0000000000032f84 RDI: 0000000000032f85
RBP: 0000000000000fd0 R08: ffffffff82316961 R09: ffffffff811c8ff5
R10: ffff8881f30c2f40 R11: 0000000000000002 R12: ffffffff846015d0
R13: fffffe0000000fd8 R14: ffff8881efb50000 R15: fffffe0000000fdb
FS:  00007fdd255796c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000005c CR3: 00000001f0e84000 CR4: 00000000003426b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400