bisecting fixing commit since d183c8e2647a7d45202c14a33631f6c09020f8ac building syzkaller on dd56146d2611f7de0fbb7d8db6c016d3dcdc6371 testing commit d183c8e2647a7d45202c14a33631f6c09020f8ac with gcc (GCC) 8.1.0 kernel signature: 7d65fbad6a9175771313a15cf940a4d3b35403a064bd66a0abc6819fc3eac413 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 a87f96283793d58b042618c689630db264715274 testing commit a87f96283793d58b042618c689630db264715274 with gcc (GCC) 8.1.0 kernel signature: 4e3903319737fa50cec3031998f94b2cf27eeba782a0f1ad68bd2a28775a6466 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: 36m11.668089124s (build: 15m56.708039445s, test: 19m27.015338035s) the crash still happens on HEAD commit msg: Linux 4.19.145 crash: general protection fault in prepare_to_wait IPv6: ADDRCONF(NETDEV_CHANGE): veth0_macvtap: link becomes ready device veth0_macvtap entered promiscuous mode IPv6: ADDRCONF(NETDEV_UP): macvtap0: link is not ready kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 7780 Comm: syz-executor.0 Not tainted 4.19.145-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 IPv6: ADDRCONF(NETDEV_UP): veth0_to_batadv: link is not ready RIP: 0010:__lock_acquire+0x1e0/0x4980 kernel/locking/lockdep.c:3294 Code: 28 00 00 00 0f 85 2a 30 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 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 28 32 00 00 49 81 7d 00 60 75 5d 89 0f 84 4a ff RSP: 0018:ffff88808e18f900 EFLAGS: 00010006 device veth1_macvtap entered promiscuous mode RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000003 RSI: 0000000000000000 RDI: ffffffff88520b00 RBP: ffff88808e18faf0 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000018 R14: ffff88808e26e300 R15: 0000000000000000 FS: 00007eff37c46700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f960dc45db8 CR3: 000000008e730000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: IPv6: ADDRCONF(NETDEV_UP): macsec0: link is not ready lock_acquire+0x173/0x3d0 kernel/locking/lockdep.c:3907 IPv6: ADDRCONF(NETDEV_UP): veth0_to_batadv: link is not ready __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x99/0xd0 kernel/locking/spinlock.c:152 prepare_to_wait+0x90/0x310 kernel/sched/wait.c:230 IPv6: ADDRCONF(NETDEV_UP): veth1_to_batadv: link is not ready nr_accept+0x1b0/0x640 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 __sys_accept4+0x32b/0x6b0 net/socket.c:1589 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! __do_sys_accept net/socket.c:1630 [inline] __se_sys_accept net/socket.c:1627 [inline] __x64_sys_accept+0x70/0xb0 net/socket.c:1627 batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! RIP: 0033:0x45b3c9 Code: 2d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb b5 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007eff37c45c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002b RAX: ffffffffffffffda RBX: 00007eff37c466d4 RCX: 000000000045b3c9 RDX: 0000000020000100 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000 batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000000 R14: 00000000004c15d8 R15: 000000000075c07c Modules linked in: ---[ end trace 726940dad527a07e ]--- batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! RIP: 0010:__lock_acquire+0x1e0/0x4980 kernel/locking/lockdep.c:3294 Code: 28 00 00 00 0f 85 2a 30 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 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 28 32 00 00 49 81 7d 00 60 75 5d 89 0f 84 4a ff RSP: 0018:ffff88808e18f900 EFLAGS: 00010006 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000003 RSI: 0000000000000000 RDI: ffffffff88520b00 RBP: ffff88808e18faf0 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000018 R14: ffff88808e26e300 R15: 0000000000000000 FS: 00007eff37c46700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f960dc45db8 CR3: 000000008e730000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400