bisecting cause commit starting from f2850dd5ee015bd7b77043f731632888887689c7 building syzkaller on 84f4fc8afc9aedba4b3afa4bb76c3df6c6352c07 testing commit f2850dd5ee015bd7b77043f731632888887689c7 with gcc (GCC) 8.1.0 kernel signature: cf7006b78a49d3adfa475e04558d1c37035fd2d4f8f2833997c0c055295eccb0 all runs: crashed: general protection fault in fbcon_cursor testing release v5.5 testing commit d5226fa6dbae0569ee43ecfc08bdcd6770fc4755 with gcc (GCC) 8.1.0 kernel signature: 2f7744994861c320e2ad03447fc973fc245f4619a9f428ebc7972dfc462dd1f9 all runs: crashed: general protection fault in fbcon_cursor testing release v5.4 testing commit 219d54332a09e8d8741c1e1982f5eae56099de85 with gcc (GCC) 8.1.0 kernel signature: 85654c735e8f8120e247daef91af4e7e0a25bfbcfca54c9424f185071472a044 all runs: crashed: general protection fault in fbcon_cursor testing release v5.3 testing commit 4d856f72c10ecb060868ed10ff1b1453943fc6c8 with gcc (GCC) 8.1.0 kernel signature: 947bdd5ee25ee697432f8954885ef8667e41e3e8de1cd5a8c1f79960144b3542 all runs: crashed: general protection fault in fbcon_cursor testing release v5.2 testing commit 0ecfebd2b52404ae0c54a878c872bb93363ada36 with gcc (GCC) 8.1.0 kernel signature: 463d5020b303f1065d4bdf1ee13fdd9ab9b1740d7aa1b52e884de450e7fb145c all runs: crashed: general protection fault in fbcon_cursor testing release v5.1 testing commit e93c9c99a629c61837d5a7fc2120cd2b6c70dbdd with gcc (GCC) 8.1.0 kernel signature: 882084c6a2cd2e9c7f9503514f5a2bb89e2688df4f4f3aa7de7ea4b185210ff4 all runs: crashed: general protection fault in fbcon_cursor testing release v5.0 testing commit 1c163f4c7b3f621efff9b28a47abb36f7378d783 with gcc (GCC) 8.1.0 kernel signature: 36527da01d377c4f1eab0f99eaf570191b45c1c6848a0cc1207e1e8460426153 all runs: crashed: general protection fault in fbcon_cursor testing release v4.20 testing commit 8fe28cb58bcb235034b64cbbb7550a8a43fd88be with gcc (GCC) 8.1.0 kernel signature: ee1662a43e9ecc14fcd95f992df3c9c80759d38eeeec671415fc09eacf6d012c all runs: crashed: general protection fault in fbcon_cursor testing release v4.19 testing commit 84df9525b0c27f3ebc2ebb1864fa62a97fdedb7d with gcc (GCC) 8.1.0 kernel signature: 21e2ce5671f1ca7d807a5d00c55a4357316188c59b08ad357c83cf54dff5009d all runs: crashed: general protection fault in fbcon_cursor testing release v4.18 testing commit 94710cac0ef4ee177a63b5227664b38c95bbf703 with gcc (GCC) 8.1.0 kernel signature: 6fbeb0ae23f70758be062a72e971acf4598b954a5e39621ee133578d14634e2f all runs: crashed: general protection fault in fbcon_cursor testing release v4.17 testing commit 29dcea88779c856c7dc92040a0c01233263101d4 with gcc (GCC) 8.1.0 kernel signature: 594c6b02552ab12c36cc4f69b244f1456945a71fec685599a00de90fbf94a4bd all runs: crashed: general protection fault in fbcon_cursor testing release v4.16 testing commit 0adb32858b0bddf4ada5f364a84ed60b196dbcda with gcc (GCC) 8.1.0 kernel signature: 820df4e11885b382245b11bc9d20ed02a455df831889245b33afd63ea3999e62 all runs: crashed: general protection fault in fbcon_cursor testing release v4.15 testing commit d8a5b80568a9cb66810e75b182018e9edb68e8ff with gcc (GCC) 8.1.0 kernel signature: 6598fed21beb9ef7f677b234d073ae53e2dfe3cb01e0de5dc1c8c98024c1ed0d all runs: crashed: general protection fault in fbcon_cursor testing release v4.14 testing commit bebc6082da0a9f5d47a1ea2edc099bf671058bd4 with gcc (GCC) 8.1.0 kernel signature: 7012ebc937113ebcbde47c8b098d3ac9ff12e2ea86fcf45c30fb82acd8d2ee33 all runs: crashed: general protection fault in fbcon_cursor testing release v4.13 testing commit 569dbb88e80deb68974ef6fdd6a13edb9d686261 with gcc (GCC) 8.1.0 kernel signature: b10b8a8bbf58f2ce2e094dc70fa1e50f0481dae00590d9732e74287a361ef95a all runs: crashed: general protection fault in fbcon_cursor testing release v4.12 testing commit 6f7da290413ba713f0cdd9ff1a2a9bb129ef4f6c with gcc (GCC) 8.1.0 kernel signature: 4f04142505c2c02d7dcedbe542421143a2e8b86cbefe8a542cb4db153019e6d4 all runs: crashed: BUG: sleeping function called from invalid context in tap_get_minor testing release v4.11 testing commit a351e9b9fc24e982ec2f0e76379a49826036da12 with gcc (GCC) 7.3.0 kernel signature: fa8b7da6ceffbefca95aadffdb095dc4b5ae264c410cf68fc18799eb3b6da678 all runs: crashed: BUG: sleeping function called from invalid context in tap_get_minor testing release v4.10 testing commit c470abd4fde40ea6a0846a2beab642a578c0b8cd with gcc (GCC) 5.5.0 kernel signature: ef5bbfa68874aae676382976d60fda57389914893d4c5801da0c735097713b05 all runs: crashed: general protection fault in do_update_region testing release v4.9 testing commit 69973b830859bc6529a7a0468ba0d80ee5117826 with gcc (GCC) 5.5.0 kernel signature: 5fc7d8b8001f5c5e17d422b577caa65946434a689186ed3e526e1b4bc0516b79 all runs: crashed: general protection fault in do_update_region testing release v4.8 testing commit c8d2bc9bc39ebea8437fd974fdbc21847bb897a3 with gcc (GCC) 5.5.0 kernel signature: 1a842390e24e557f7c3019a5bd25cd589a523b080703ac93eeea571d3a050c36 all runs: crashed: general protection fault in do_update_region testing release v4.7 testing commit 523d939ef98fd712632d93a5a2b588e477a7565e with gcc (GCC) 5.5.0 kernel signature: cfd446062657ee27736af5cf8ce3c5edc0b9285ad3363c7180474cbc3c68359d all runs: crashed: general protection fault in do_update_region testing release v4.6 testing commit 2dcd0af568b0cf583645c8a317dd12e344b1c72a with gcc (GCC) 5.5.0 kernel signature: 269b735abf7e7c2d24c9644a17f99f97faf0374b5afbd176980dbd32f4f0f0bf all runs: crashed: WARNING in sysfs_warn_dup revisions tested: 22, total time: 3h19m45.579766098s (build: 1h58m54.52251795s, test: 1h18m36.469640042s) the crash already happened on the oldest tested release commit msg: Linux 4.6 crash: WARNING in sysfs_warn_dup IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready bond0: Enslaving bond_slave_1 as an active interface with an up link IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready ------------[ cut here ]------------ WARNING: CPU: 0 PID: 7553 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x7b/0xa0 fs/sysfs/dir.c:30 sysfs: cannot create duplicate filename '/class/macvtap/tap50' Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 7553 Comm: syz-executor.0 Not tainted 4.6.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 1ffffffff0d95756 ffff8800b3dd6fb0 ffffffff82c74fc6 ffffffff85c81040 ffff8800b3dd7088 ffffffff85d2bac0 ffffffff81922ccb ffff8800b3dd7078 ffffffff8160cf4e 0000000041b58ab3 ffffffff868f2161 ffffffff8160cd9f Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xe6/0x120 lib/dump_stack.c:51 [] panic+0x1af/0x348 kernel/panic.c:152 [] __warn+0x18d/0x1b0 kernel/panic.c:504 [] warn_slowpath_fmt+0x92/0xb0 kernel/panic.c:527 [] sysfs_warn_dup+0x7b/0xa0 fs/sysfs/dir.c:30 [] sysfs_do_create_link_sd.isra.2+0xd1/0xf0 fs/sysfs/symlink.c:51 [] sysfs_do_create_link fs/sysfs/symlink.c:80 [inline] [] sysfs_create_link+0x43/0xb0 fs/sysfs/symlink.c:92 [] device_add_class_symlinks drivers/base/core.c:891 [inline] [] device_add+0x689/0x1360 drivers/base/core.c:1086 [] device_create_groups_vargs+0x1c8/0x220 drivers/base/core.c:1709 [] device_create_vargs drivers/base/core.c:1749 [inline] [] device_create+0x88/0xa0 drivers/base/core.c:1785 [] macvtap_device_event+0x1c4/0x2a0 drivers/net/macvtap.c:1298 [] notifier_call_chain+0x8b/0x170 kernel/notifier.c:93 [] __raw_notifier_call_chain kernel/notifier.c:394 [inline] [] raw_notifier_call_chain+0x11/0x20 kernel/notifier.c:401 [] call_netdevice_notifiers_info+0x47/0x80 net/core/dev.c:1643 [] call_netdevice_notifiers net/core/dev.c:1659 [inline] [] register_netdevice+0x88a/0xce0 net/core/dev.c:7027 [] macvlan_common_newlink+0x8b9/0x1090 drivers/net/macvlan.c:1316 [] macvtap_newlink+0xbf/0x110 drivers/net/macvtap.c:471 [] rtnl_newlink+0xd4b/0x1230 net/core/rtnetlink.c:2466 [] rtnetlink_rcv_msg+0x222/0x680 net/core/rtnetlink.c:3513 [] netlink_rcv_skb+0x242/0x350 net/netlink/af_netlink.c:2277 [] rtnetlink_rcv+0x25/0x30 net/core/rtnetlink.c:3519 [] netlink_unicast_kernel net/netlink/af_netlink.c:1214 [inline] [] netlink_unicast+0x455/0x660 net/netlink/af_netlink.c:1240 [] netlink_sendmsg+0x893/0xb40 net/netlink/af_netlink.c:1786 [] sock_sendmsg_nosec net/socket.c:612 [inline] [] sock_sendmsg+0xb5/0xf0 net/socket.c:622 [] SYSC_sendto+0x1c9/0x300 net/socket.c:1648 [] SyS_sendto+0x9/0x10 net/socket.c:1616 [] entry_SYSCALL_64_fastpath+0x23/0xc1 Kernel Offset: disabled