bisecting fixing commit since 45f092f9e9cb31486db546e39bfe7cc0b3f57099 building syzkaller on cfc9868f25f37077a00800c89ed55586a333cdf3 testing commit 45f092f9e9cb31486db546e39bfe7cc0b3f57099 with gcc (GCC) 8.1.0 kernel signature: 5fbc5bbe7639e8d4930d0a520cca9583fd2ea110 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: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing current HEAD a844dc4c544291470aa69edbe2434b040794e269 testing commit a844dc4c544291470aa69edbe2434b040794e269 with gcc (GCC) 8.1.0 kernel signature: 882af1e369de743b7f5f15fa7e6cb71b4cb1d8ed run #0: crashed: general protection fault in prepare_to_wait run #1: OK run #2: OK run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK revisions tested: 2, total time: 36m33.017377773s (build: 15m59.348836683s, test: 19m55.090719819s) the crash still happens on HEAD commit msg: Linux 4.14.158 crash: general protection fault in prepare_to_wait IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bond: link becomes ready IPv6: ADDRCONF(NETDEV_UP): veth1_to_hsr: link is not ready hsr0: Slave B (hsr_slave_1) is not up; please bring it up to get a fully working HSR network 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 Modules linked in: CPU: 1 PID: 6806 Comm: syz-executor.2 Not tainted 4.14.158-syzkaller #0 kobject: 'loop1' (ffff8880a4a2ef20): kobject_uevent_env Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff88808c256300 task.stack: ffff88808e018000 RIP: 0010:__lock_acquire+0x1d5/0x4500 kernel/locking/lockdep.c:3365 RSP: 0018:ffff88808e01f8f0 EFLAGS: 00010006 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000003 RSI: 0000000000000000 RDI: ffffffff879169c0 RBP: ffff88808e01fac0 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000001 R11: ffff88808c256300 R12: 0000000000000018 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000 FS: 00007fe579074700(0000) GS:ffff8880aef00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb2e9fe4db8 CR3: 0000000091d3c000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kobject: 'loop1' (ffff8880a4a2ef20): fill_kobj_path: path = '/devices/virtual/block/loop1' lock_acquire+0x173/0x400 kernel/locking/lockdep.c:3994 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x99/0xd0 kernel/locking/spinlock.c:160 prepare_to_wait+0x8a/0x3b0 kernel/sched/wait.c:234 nr_accept+0x1a8/0x670 net/netrom/af_netrom.c:796 SYSC_accept4+0x306/0x5e0 net/socket.c:1587 SyS_accept4+0x9/0x10 net/socket.c:1537 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x459829 RSP: 002b:00007fe579073c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000120 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000459829 RDX: 0000000020000240 RSI: 00000000200002c0 RDI: 0000000000000006 RBP: 000000000075c118 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000800 R11: 0000000000000246 R12: 00007fe5790746d4 R13: 00000000004bf7c8 R14: 00000000004d1230 R15: 00000000ffffffff 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 a0 e2 7a 88 0f 84 30 RIP: __lock_acquire+0x1d5/0x4500 kernel/locking/lockdep.c:3365 RSP: ffff88808e01f8f0 ---[ end trace 9bdd849efb4b2046 ]---