bisecting fixing commit since 9fa690a2a016e1b55356835f047b952e67d3d73a building syzkaller on 5ed23f9aa677d71bc60f61df8e05046151868541 testing commit 9fa690a2a016e1b55356835f047b952e67d3d73a with gcc (GCC) 8.1.0 kernel signature: 776bf39bc99196be74053b4f913d91e0e28cf549b43b29f4c1c7bda977e29765 run #0: crashed: general protection fault in prepare_to_wait run #1: crashed: general protection fault in prepare_to_wait run #2: crashed: general protection fault in prepare_to_wait run #3: crashed: general protection fault in prepare_to_wait run #4: crashed: general protection fault in prepare_to_wait run #5: crashed: general protection fault in prepare_to_wait run #6: crashed: general protection fault in prepare_to_wait run #7: OK run #8: OK run #9: OK testing current HEAD 4f68020fef1c6cf1b680ffb6481ac41379283ea3 testing commit 4f68020fef1c6cf1b680ffb6481ac41379283ea3 with gcc (GCC) 8.1.0 kernel signature: fa4c2ac1cd671717bcb9ba5666f0c82af9dac33d6d6065f75222d76b42332ec7 run #0: crashed: general protection fault in prepare_to_wait run #1: crashed: general protection fault in prepare_to_wait run #2: crashed: general protection fault in prepare_to_wait run #3: crashed: general protection fault in prepare_to_wait run #4: crashed: general protection fault in prepare_to_wait run #5: crashed: general protection fault in prepare_to_wait run #6: crashed: general protection fault in prepare_to_wait run #7: OK run #8: OK run #9: OK revisions tested: 2, total time: 37m44.921166194s (build: 17m8.243823143s, test: 19m59.509304181s) the crash still happens on HEAD commit msg: Linux 4.14.182 crash: general protection fault in prepare_to_wait batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! kasan: CONFIG_KASAN_INLINE enabled batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] PREEMPT SMP KASAN Modules linked in: CPU: 1 PID: 7708 Comm: syz-executor.2 Not tainted 4.14.182-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8880a771a280 task.stack: ffff8880899b0000 RIP: 0010:__lock_acquire+0x1d5/0x4500 kernel/locking/lockdep.c:3369 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! RSP: 0018:ffff8880899b78f0 EFLAGS: 00010006 IPv6: ADDRCONF(NETDEV_UP): batadv_slave_1: link is not ready RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 batman_adv: batadv0: Interface activated: batadv_slave_1 RDX: 0000000000000003 RSI: 0000000000000000 RDI: ffffffff87f16680 RBP: ffff8880899b7ac0 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000001 R11: ffff8880a771a280 R12: 0000000000000018 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000 FS: 00007fa15bbcf700(0000) GS:ffff8880aed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa15bb6bdb8 CR3: 0000000089927000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 device veth0_macvtap entered promiscuous mode DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: IPv6: ADDRCONF(NETDEV_UP): macvtap0: link is not ready batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 lock_acquire+0x173/0x400 kernel/locking/lockdep.c:3998 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x99/0xd0 kernel/locking/spinlock.c:160 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! prepare_to_wait+0x8a/0x3b0 kernel/sched/wait.c:234 batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! nr_accept+0x1a8/0x670 net/netrom/af_netrom.c:796 batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! SYSC_accept4+0x306/0x5e0 net/socket.c:1587 IPv6: ADDRCONF(NETDEV_UP): batadv_slave_0: link is not ready batman_adv: batadv0: Interface activated: batadv_slave_0 batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 SyS_accept4 net/socket.c:1537 [inline] SYSC_accept net/socket.c:1621 [inline] SyS_accept+0xb/0x10 net/socket.c:1618 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 IPv6: ADDRCONF(NETDEV_UP): batadv_slave_1: link is not ready batman_adv: batadv0: Interface activated: batadv_slave_1 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x45b349 RSP: 002b:00007fa15bbcec78 EFLAGS: 00000246 ORIG_RAX: 000000000000002b RAX: ffffffffffffffda RBX: 00007fa15bbcf6d4 RCX: 000000000045b349 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000000 R14: 00000000004c1558 R15: 000000000075c07c Code: 00 00 00 00 8b 84 24 98 00 00 00 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 48 b8 00 00 00 00 00 fc ff df 4c 89 e2 48 c1 ea 03 <80> 3c 02 00 0f 85 f2 30 00 00 49 81 3c 24 e0 e4 e7 88 0f 84 30 RIP: __lock_acquire+0x1d5/0x4500 kernel/locking/lockdep.c:3369 RSP: ffff8880899b78f0 ---[ end trace 8ae599b4ce9e96ea ]---