perf buffer not large enough
------------[ cut here ]------------
WARNING: CPU: 0 PID: 25655 at kernel/trace/trace_event_perf.c:274 perf_trace_buf_alloc+0x12d/0x160 kernel/trace/trace_event_perf.c:273
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 25655 Comm: syz-executor1 Not tainted 4.14.0-rc7+ #159
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 panic+0x1e4/0x417 kernel/panic.c:181
 __warn+0x1c4/0x1d9 kernel/panic.c:542
 report_bug+0x211/0x2d0 lib/bug.c:184
 fixup_bug+0x40/0x90 arch/x86/kernel/traps.c:178
 do_trap_no_signal arch/x86/kernel/traps.c:212 [inline]
 do_trap+0x260/0x390 arch/x86/kernel/traps.c:261
 do_error_trap+0x120/0x390 arch/x86/kernel/traps.c:298
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:311
 invalid_op+0x18/0x20 arch/x86/entry/entry_64.S:906
RIP: 0010:perf_trace_buf_alloc+0x12d/0x160 kernel/trace/trace_event_perf.c:273
RSP: 0018:ffff8801d67cf760 EFLAGS: 00010286
RAX: 000000000000001c RBX: 1ffff1003acf9efe RCX: 0000000000000000
RDX: 000000000000001c RSI: ffffffff8158842e RDI: ffffed003acf9ee0
RBP: ffff8801d67cf780 R08: 0000000000000001 R09: 0000000000000000
R10: ffff8801d67cf7a0 R11: 0000000000000000 R12: 0000000000000d9c
R13: ffff8801d67cf810 R14: ffff8801d67cf890 R15: ffff8801c67a9840
 perf_trace_bpf_map_keyval+0x260/0xbd0 include/trace/events/bpf.h:228
 trace_bpf_map_update_elem include/trace/events/bpf.h:274 [inline]
 map_update_elem kernel/bpf/syscall.c:597 [inline]
 SYSC_bpf kernel/bpf/syscall.c:1478 [inline]
 SyS_bpf+0x33eb/0x46a0 kernel/bpf/syscall.c:1453
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x452869
RSP: 002b:00007f3c10bfbbe8 EFLAGS: 00000212 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 0000000000758020 RCX: 0000000000452869
RDX: 0000000000000020 RSI: 000000002053dfe0 RDI: 0000000000000002
RBP: 0000000000000082 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006ee1d8
R13: 00000000ffffffff R14: 00007f3c10bfc6d4 R15: 0000000000000000
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..