bisecting fixing commit since e6986423d28362aafe64d3757bbbc493f2687f8f building syzkaller on b0e8efcb4b0aac61f4647a76bbe54a5d38a370ba testing commit e6986423d28362aafe64d3757bbbc493f2687f8f with gcc (GCC) 8.1.0 run #0: crashed: INFO: trying to register non-static key in __icmp_send run #1: crashed: WARNING: bad unlock balance detected! run #2: crashed: unregister_netdevice: waiting for DEV to become free run #3: crashed: general protection fault in fib6_purge_rt run #4: crashed: unregister_netdevice: waiting for DEV to become free run #5: crashed: unregister_netdevice: waiting for DEV to become free run #6: crashed: unregister_netdevice: waiting for DEV to become free run #7: crashed: kernel BUG at net/ipv6/route.c:LINE! run #8: crashed: general protection fault in fib6_purge_rt run #9: crashed: unregister_netdevice: waiting for DEV to become free testing current HEAD cfef46d692efd852a0da6803f920cc756eea2855 testing commit cfef46d692efd852a0da6803f920cc756eea2855 with gcc (GCC) 8.1.0 all runs: crashed: BUG: using smp_processor_id() in preemptible [ADDR] code: syz-executor revisions tested: 2, total time: 25m4.956973959s (build: 11m44.718334534s, test: 11m38.964904297s) the crash still happens on HEAD crash: BUG: using smp_processor_id() in preemptible [ADDR] code: syz-executor Started in network mode Own node identity ac1414aa, cluster identity 4711 New replicast peer: 172.20.20.187 check_preemption_disabled: 8 callbacks suppressed BUG: using smp_processor_id() in preemptible [00000000] code: syz-executor.3/7206 caller is dst_cache_get+0x33/0xa0 net/core/dst_cache.c:68 CPU: 0 PID: 7206 Comm: syz-executor.3 Not tainted 5.3.0-rc3+ #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x113/0x167 lib/dump_stack.c:113 check_preemption_disabled lib/smp_processor_id.c:47 [inline] debug_smp_processor_id.cold.2+0x84/0x97 lib/smp_processor_id.c:57 dst_cache_get+0x33/0xa0 net/core/dst_cache.c:68 tipc_udp_xmit.isra.15+0xb9/0xc60 net/tipc/udp_media.c:164 tipc_udp_send_msg+0x229/0x3d0 net/tipc/udp_media.c:254 tipc_bearer_xmit_skb+0x12c/0x290 net/tipc/bearer.c:503 tipc_enable_bearer+0x7a6/0xab0 net/tipc/bearer.c:328 __tipc_nl_bearer_enable+0x265/0x390 net/tipc/bearer.c:899 tipc_nl_bearer_enable+0x1d/0x30 net/tipc/bearer.c:907 genl_family_rcv_msg+0x5d5/0x1150 net/netlink/genetlink.c:629 genl_rcv_msg+0xa7/0x140 net/netlink/genetlink.c:654 netlink_rcv_skb+0x13f/0x380 net/netlink/af_netlink.c:2477 genl_rcv+0x23/0x40 net/netlink/genetlink.c:665 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x444/0x640 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x75d/0xc40 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xe6/0x110 net/socket.c:657 ___sys_sendmsg+0x658/0x980 net/socket.c:2311 __sys_sendmsg+0xd9/0x180 net/socket.c:2356 __do_sys_sendmsg net/socket.c:2365 [inline] __se_sys_sendmsg net/socket.c:2363 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2363 do_syscall_64+0xd6/0x550 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458c29 Code: ad b8 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 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f94de184c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458c29 RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 000000000000000a RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f94de1856d4 R13: 00000000004c62bc R14: 00000000004dab98 R15: 00000000ffffffff BUG: using smp_processor_id() in preemptible [00000000] code: syz-executor.3/7206 caller is dst_cache_set_ip4+0x97/0x2dc net/core/dst_cache.c:98 CPU: 1 PID: 7206 Comm: syz-executor.3 Not tainted 5.3.0-rc3+ #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x113/0x167 lib/dump_stack.c:113 check_preemption_disabled lib/smp_processor_id.c:47 [inline] debug_smp_processor_id.cold.2+0x84/0x97 lib/smp_processor_id.c:57 dst_cache_set_ip4+0x97/0x2dc net/core/dst_cache.c:98 tipc_udp_xmit.isra.15+0x7c2/0xc60 net/tipc/udp_media.c:182 tipc_udp_send_msg+0x229/0x3d0 net/tipc/udp_media.c:254 tipc_bearer_xmit_skb+0x12c/0x290 net/tipc/bearer.c:503 tipc_enable_bearer+0x7a6/0xab0 net/tipc/bearer.c:328 __tipc_nl_bearer_enable+0x265/0x390 net/tipc/bearer.c:899 tipc_nl_bearer_enable+0x1d/0x30 net/tipc/bearer.c:907 genl_family_rcv_msg+0x5d5/0x1150 net/netlink/genetlink.c:629 genl_rcv_msg+0xa7/0x140 net/netlink/genetlink.c:654 netlink_rcv_skb+0x13f/0x380 net/netlink/af_netlink.c:2477 genl_rcv+0x23/0x40 net/netlink/genetlink.c:665 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x444/0x640 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x75d/0xc40 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xe6/0x110 net/socket.c:657 ___sys_sendmsg+0x658/0x980 net/socket.c:2311 __sys_sendmsg+0xd9/0x180 net/socket.c:2356 __do_sys_sendmsg net/socket.c:2365 [inline] __se_sys_sendmsg net/socket.c:2363 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2363 do_syscall_64+0xd6/0x550 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458c29 Code: ad b8 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 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f94de184c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458c29 RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 000000000000000a RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f94de1856d4 R13: 00000000004c62bc R14: 00000000004dab98 R15: 00000000ffffffff Enabled bearer , priority 10