bisecting fixing commit since 97ab07e11fbf55c86c3758e07ab295028bf17f94 building syzkaller on cd626f3ba9f85027426d4fbed73e79e523e8e138 testing commit 97ab07e11fbf55c86c3758e07ab295028bf17f94 with gcc (GCC) 8.4.1 20210217 kernel signature: d0e57fc49cd421bcfd137e5dd23e3d0ad0debab4f3de6b3b37933d9a2fde8bd0 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: OK run #6: OK run #7: OK run #8: OK run #9: OK run #10: OK run #11: OK run #12: OK run #13: OK run #14: OK run #15: OK run #16: OK run #17: OK run #18: OK run #19: OK reproducer seems to be flaky testing current HEAD 255b58a2b3af0baa0ee11507390349217b8b73b0 testing commit 255b58a2b3af0baa0ee11507390349217b8b73b0 with gcc (GCC) 8.4.1 20210217 kernel signature: 3ca57a32ad3fed69f65eabd60515123ce7d964fdcc364aa160f8a7b95086f3f3 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: OK run #6: OK run #7: OK run #8: OK run #9: OK run #10: OK run #11: OK run #12: OK run #13: OK run #14: OK run #15: OK run #16: OK run #17: OK run #18: OK run #19: OK Reproducer flagged being flaky revisions tested: 2, total time: 39m30.96785763s (build: 15m13.419683435s, test: 23m19.083593326s) the crash still happens on HEAD commit msg: Linux 4.19.176 crash: general protection fault in prepare_to_wait 8021q: adding VLAN 0 to HW filter on device batadv0 IPv6: ADDRCONF(NETDEV_UP): vxcan1: link is not ready 8021q: adding VLAN 0 to HW filter on device batadv0 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: 1 PID: 6583 Comm: syz-executor.1 Not tainted 4.19.176-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__lock_acquire+0x1e0/0x4950 kernel/locking/lockdep.c:3294 Code: 28 00 00 00 0f 85 06 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 e2 31 00 00 49 81 7d 00 a0 71 0b 89 0f 84 4a ff RSP: 0018:ffff8881e11ef900 EFLAGS: 00010006 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000003 RSI: 0000000000000000 RDI: ffffffff88120080 RBP: ffff8881e11efaf0 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000018 R14: ffff8881e0bee000 R15: 0000000000000000 FS: 00007ff9fe6b0700(0000) GS:ffff8881f6900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff9fe66e718 CR3: 00000001e29dc005 CR4: 00000000001606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x173/0x3d0 kernel/locking/lockdep.c:3907 __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 nr_accept+0x1b0/0x640 net/netrom/af_netrom.c:796 __sys_accept4+0x32b/0x6b0 net/socket.c:1589 __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 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4610d9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ff9fe6b01a8 EFLAGS: 00000246 ORIG_RAX: 000000000000002b RAX: ffffffffffffffda RBX: 000000000052c050 RCX: 00000000004610d9 RDX: 0000000020000080 RSI: 0000000020000280 RDI: 0000000000000004 RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004e9c80 R14: 00000000004ab499 R15: 00007ff9fe6b06bc Modules linked in: ---[ end trace cb05566e5ddb6fc9 ]--- RIP: 0010:__lock_acquire+0x1e0/0x4950 kernel/locking/lockdep.c:3294 Code: 28 00 00 00 0f 85 06 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 e2 31 00 00 49 81 7d 00 a0 71 0b 89 0f 84 4a ff RSP: 0018:ffff8881e11ef900 EFLAGS: 00010006 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000003 RSI: 0000000000000000 RDI: ffffffff88120080 RBP: ffff8881e11efaf0 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000018 R14: ffff8881e0bee000 R15: 0000000000000000 FS: 00007ff9fe6b0700(0000) GS:ffff8881f6900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff9fe66e718 CR3: 00000001e29dc005 CR4: 00000000001606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400