bisecting fixing commit since 27ce4f2a6817e38ca74c643d47a96359f6cc0c1c
building syzkaller on 1bf9a662c66aa432ff2fe3bf2562578cef626c09
testing commit 27ce4f2a6817e38ca74c643d47a96359f6cc0c1c with gcc (GCC) 8.4.1 20210217
kernel signature: 9adae58a2fb48f67f4cd4b780f69ffe1d308535dca58213b2f67e6f69db6e700
all runs: crashed: WARNING in bpf
testing current HEAD 29c52025152bab4c557d8174da58f1a4c8e70438
testing commit 29c52025152bab4c557d8174da58f1a4c8e70438 with gcc (GCC) 8.4.1 20210217
kernel signature: 7b02f0f76a35566432173cabb9484edb42994729a95ebeed31ba7946ea93eae0
all runs: crashed: WARNING in bpf
revisions tested: 2, total time: 21m33.997767342s (build: 13m55.527716258s, test: 6m21.362719656s)
the crash still happens on HEAD
commit msg: Linux 4.14.221
crash: WARNING in bpf
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
perf buffer not large enough
------------[ cut here ]------------
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1
WARNING: CPU: 0 PID: 9122 at kernel/trace/trace_event_perf.c:274 perf_trace_buf_alloc.cold.2+0x13/0x1c kernel/trace/trace_event_perf.c:273
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 9122 Comm: syz-executor.1 Not tainted 4.14.221-syzkaller #0
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+0x14b/0x1e7 lib/dump_stack.c:58
 panic+0x1b0/0x358 kernel/panic.c:183
 __warn.cold.7+0x25/0x25 kernel/panic.c:547
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
 report_bug+0x1a1/0x200 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:177 [inline]
 fixup_bug arch/x86/kernel/traps.c:172 [inline]
 do_error_trap+0x1bd/0x310 arch/x86/kernel/traps.c:295
IPv6: ADDRCONF(NETDEV_UP): batadv_slave_1: link is not ready
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:314
 invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:964
RIP: 0010:perf_trace_buf_alloc.cold.2+0x13/0x1c kernel/trace/trace_event_perf.c:273
RSP: 0018:ffff8881df2c7c10 EFLAGS: 00010282
RAX: 000000000000001c RBX: ffff8881e6c1431c RCX: 0000000000000000
RDX: 000000000000001c RSI: 0000000000000001 RDI: ffffed103be58f79
RBP: ffff8881df2c7c38 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: dffffc0000000000 R12: 0000000000209e54
R13: 0000000000209e54 R14: ffff8881e6c14300 R15: 0000000000000000
 perf_trace_bpf_map_keyval+0x1ba/0x830 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:612 [inline]
 SYSC_bpf kernel/bpf/syscall.c:1503 [inline]
 SyS_bpf+0x23c4/0x2fc0 kernel/bpf/syscall.c:1477
 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x465889
RSP: 002b:00007fdd97347188 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 000000000055bf00 RCX: 0000000000465889
RDX: 0000000000000020 RSI: 0000000020000040 RDI: 0000000000000002
RBP: 00000000004af68d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000055bf00
R13: 00007ffeef935edf R14: 00007fdd97347300 R15: 0000000000022000
Kernel Offset: disabled
Rebooting in 86400 seconds..