bisecting cause commit starting from ac935d22736659be734251247dcc6f444fb98972 building syzkaller on 3698959af9a7a34fa3fb3ddf999034a66f4e886f testing commit ac935d22736659be734251247dcc6f444fb98972 with gcc (GCC) 8.1.0 kernel signature: 3e1119b04951e0cd410e944adfb992d5b6ae5d6357a1a5038373c4408a1f959e all runs: crashed: no output from test machine testing release v5.6 testing commit 7111951b8d4973bda27ff663f2cf18b663d15b48 with gcc (GCC) 8.1.0 kernel signature: 572560ae2b3a72ae58a7e23d37803d6b9911463392e6cc1833dbecc168c101b5 all runs: crashed: no output from test machine testing release v5.5 testing commit d5226fa6dbae0569ee43ecfc08bdcd6770fc4755 with gcc (GCC) 8.1.0 kernel signature: 45aee7f17e5cd1e14b98441ae9b7ea0bca038da1e5cddee62391e21c61e4f6fe all runs: crashed: no output from test machine testing release v5.4 testing commit 219d54332a09e8d8741c1e1982f5eae56099de85 with gcc (GCC) 8.1.0 kernel signature: 41e42e0bcad9fa16b5848d6c32ca3dbb0bae5e58adafd59dd9703c8f2dbf1c3e run #0: crashed: unexpected kernel reboot run #1: crashed: unexpected kernel reboot run #2: crashed: unexpected kernel reboot run #3: crashed: unexpected kernel reboot run #4: crashed: unexpected kernel reboot run #5: crashed: unexpected kernel reboot run #6: crashed: unexpected kernel reboot run #7: crashed: no output from test machine run #8: crashed: no output from test machine run #9: crashed: no output from test machine testing release v5.3 testing commit 4d856f72c10ecb060868ed10ff1b1453943fc6c8 with gcc (GCC) 8.1.0 kernel signature: c8014ea40d2c56ad4be78a38af2562c5f323b5f218465d92d309f9273103de7b all runs: crashed: unexpected kernel reboot testing release v5.2 testing commit 0ecfebd2b52404ae0c54a878c872bb93363ada36 with gcc (GCC) 8.1.0 kernel signature: aa791796ae640e61e27fdc5998b71654c62947c6bb8ee7ddd96c9d371a4834ed run #0: crashed: unexpected kernel reboot run #1: crashed: unexpected kernel reboot run #2: crashed: unexpected kernel reboot run #3: crashed: unexpected kernel reboot run #4: crashed: unexpected kernel reboot run #5: crashed: unexpected kernel reboot run #6: crashed: unexpected kernel reboot run #7: crashed: unexpected kernel reboot run #8: crashed: no output from test machine run #9: crashed: no output from test machine testing release v5.1 testing commit e93c9c99a629c61837d5a7fc2120cd2b6c70dbdd with gcc (GCC) 8.1.0 kernel signature: 46a0d4f98ce2f7f95e1464d65dd64e249156d0605fc89c1b25fbc9c3d0bf91a9 run #0: crashed: unexpected kernel reboot run #1: crashed: unexpected kernel reboot run #2: crashed: unexpected kernel reboot run #3: crashed: unexpected kernel reboot run #4: crashed: unexpected kernel reboot run #5: crashed: unexpected kernel reboot run #6: crashed: unexpected kernel reboot run #7: crashed: no output from test machine run #8: crashed: no output from test machine run #9: crashed: no output from test machine testing release v5.0 testing commit 1c163f4c7b3f621efff9b28a47abb36f7378d783 with gcc (GCC) 8.1.0 kernel signature: b75b54404706bd856df88a20b7fd6710be2c2a72ae5904392228fbf211971f50 run #0: crashed: unexpected kernel reboot run #1: crashed: unexpected kernel reboot run #2: crashed: unexpected kernel reboot run #3: crashed: unexpected kernel reboot run #4: crashed: unexpected kernel reboot run #5: crashed: unexpected kernel reboot run #6: crashed: unexpected kernel reboot run #7: crashed: unexpected kernel reboot run #8: crashed: unexpected kernel reboot run #9: crashed: no output from test machine testing release v4.20 testing commit 8fe28cb58bcb235034b64cbbb7550a8a43fd88be with gcc (GCC) 8.1.0 kernel signature: 095720b3cd2df8f875481f392cb690a20d946dc2a108d79fb6a8184646d3c5f2 run #0: crashed: unexpected kernel reboot run #1: crashed: unexpected kernel reboot run #2: crashed: KASAN: out-of-bounds Write in decode_operand run #3: crashed: unexpected kernel reboot run #4: crashed: unexpected kernel reboot run #5: crashed: unexpected kernel reboot run #6: crashed: unexpected kernel reboot run #7: crashed: unexpected kernel reboot run #8: crashed: unexpected kernel reboot run #9: crashed: unexpected kernel reboot testing release v4.19 testing commit 84df9525b0c27f3ebc2ebb1864fa62a97fdedb7d with gcc (GCC) 8.1.0 kernel signature: 6320ca8d3909511c44126216af4d36233ea90d9bf64cbb9c5e4590b3e1593fcc all runs: crashed: unexpected kernel reboot testing release v4.18 testing commit 94710cac0ef4ee177a63b5227664b38c95bbf703 with gcc (GCC) 8.1.0 kernel signature: 52f20de16ea1fca7c26b4d4a833674b59f1f7f6ade132d00f6c367d10122ac5e run #0: crashed: unexpected kernel reboot run #1: crashed: unexpected kernel reboot run #2: crashed: unexpected kernel reboot run #3: crashed: unexpected kernel reboot run #4: crashed: unexpected kernel reboot run #5: crashed: unexpected kernel reboot run #6: crashed: unexpected kernel reboot run #7: crashed: unexpected kernel reboot run #8: crashed: unexpected kernel reboot run #9: crashed: no output from test machine testing release v4.17 testing commit 29dcea88779c856c7dc92040a0c01233263101d4 with gcc (GCC) 8.1.0 kernel signature: 0a8320a76091cefd49fc2584333ec82a389777e9d82129d05c98b874f9beb87b all runs: crashed: unexpected kernel reboot testing release v4.16 testing commit 0adb32858b0bddf4ada5f364a84ed60b196dbcda with gcc (GCC) 8.1.0 kernel signature: ce776fa92fc78fce236434fd066161590830a500d74e86ba4eaf53cb309a97b4 run #0: crashed: unexpected kernel reboot run #1: crashed: unexpected kernel reboot run #2: crashed: unexpected kernel reboot run #3: crashed: unexpected kernel reboot run #4: crashed: unexpected kernel reboot run #5: crashed: unexpected kernel reboot run #6: crashed: unexpected kernel reboot run #7: crashed: unexpected kernel reboot run #8: crashed: no output from test machine run #9: crashed: no output from test machine testing release v4.15 testing commit d8a5b80568a9cb66810e75b182018e9edb68e8ff with gcc (GCC) 8.1.0 kernel signature: 6a68f698126da438d8a72d48b6f2363b05df41eca3c05e2a7114733e9ea2c6ca run #0: crashed: unexpected kernel reboot run #1: crashed: unexpected kernel reboot run #2: crashed: unexpected kernel reboot run #3: crashed: unexpected kernel reboot run #4: crashed: unexpected kernel reboot run #5: crashed: unexpected kernel reboot run #6: crashed: unexpected kernel reboot run #7: crashed: unexpected kernel reboot run #8: crashed: unexpected kernel reboot run #9: crashed: no output from test machine testing release v4.14 testing commit bebc6082da0a9f5d47a1ea2edc099bf671058bd4 with gcc (GCC) 8.1.0 kernel signature: 1c50d038924f2c33d1ba0e7a239f2f3c5f375e8cc56428c94f6232acee7348c4 run #0: crashed: unexpected kernel reboot run #1: crashed: unexpected kernel reboot run #2: crashed: unexpected kernel reboot run #3: crashed: unexpected kernel reboot run #4: crashed: unexpected kernel reboot run #5: crashed: unexpected kernel reboot run #6: crashed: unexpected kernel reboot run #7: crashed: unexpected kernel reboot run #8: crashed: unexpected kernel reboot run #9: crashed: no output from test machine testing release v4.13 testing commit 569dbb88e80deb68974ef6fdd6a13edb9d686261 with gcc (GCC) 8.1.0 kernel signature: 6cb184cf9a3bd16d12e33bde04d8f6c76f20ca30689747514121f1d03bc15d3f all runs: crashed: unexpected kernel reboot testing release v4.12 testing commit 6f7da290413ba713f0cdd9ff1a2a9bb129ef4f6c with gcc (GCC) 8.1.0 kernel signature: 660d0fb23f7796150142183e417ccc35e74d8a1bd32482b16693899d8384e13a 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: 8064b8bf8cd80a84c1351c2fe709bebfad93d6972f5ec0ae0031aca637afb1aa 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: e494d3d528dab4c71a5999d1fc7d40d265c4f7913802404adc3c648f3895d933 run #0: crashed: unexpected kernel reboot run #1: crashed: unexpected kernel reboot run #2: crashed: unexpected kernel reboot run #3: crashed: unexpected kernel reboot run #4: crashed: unexpected kernel reboot run #5: crashed: unexpected kernel reboot run #6: crashed: unexpected kernel reboot run #7: crashed: unexpected kernel reboot run #8: crashed: unexpected kernel reboot run #9: crashed: no output from test machine testing release v4.9 testing commit 69973b830859bc6529a7a0468ba0d80ee5117826 with gcc (GCC) 5.5.0 kernel signature: b557d023406b73904d08434c07e91b6ac44ab722c4ea707a8af3f182a4b3737d all runs: crashed: unexpected kernel reboot testing release v4.8 testing commit c8d2bc9bc39ebea8437fd974fdbc21847bb897a3 with gcc (GCC) 5.5.0 kernel signature: f98ba87d0cbedf6df04942d8a32eb737880e6e1673ee1282299402bb779632c2 run #0: crashed: unexpected kernel reboot run #1: crashed: unexpected kernel reboot run #2: crashed: unexpected kernel reboot run #3: crashed: unexpected kernel reboot run #4: crashed: unexpected kernel reboot run #5: crashed: unexpected kernel reboot run #6: crashed: unexpected kernel reboot run #7: crashed: unexpected kernel reboot run #8: crashed: no output from test machine run #9: crashed: no output from test machine testing release v4.7 testing commit 523d939ef98fd712632d93a5a2b588e477a7565e with gcc (GCC) 5.5.0 kernel signature: c032b8a91fdad9fd7d69b10e754e0557ef73f0b66d2360dd98112a652881a8b0 run #0: crashed: general protection fault in geneve_sock_add run #1: crashed: general protection fault in find_inlist_lock run #2: crashed: WARNING in evict run #3: crashed: general protection fault in ext4_release_file run #4: crashed: general protection fault in ipt_do_table run #5: crashed: WARNING: ODEBUG bug in fib6_run_gc run #6: crashed: general protection fault in do_exit run #7: crashed: general protection fault in mm_update_next_owner run #8: crashed: unexpected kernel reboot run #9: crashed: unexpected kernel reboot testing release v4.6 testing commit 2dcd0af568b0cf583645c8a317dd12e344b1c72a with gcc (GCC) 5.5.0 kernel signature: 3be083c5e28f318df422f0dbb70c8a56262898466af4e2e2ceb6ef5872db3734 all runs: crashed: WARNING in sysfs_warn_dup revisions tested: 23, total time: 4h27m12.003240093s (build: 2h5m43.001648125s, test: 2h18m36.620920718s) the crash already happened on the oldest tested release commit msg: Linux 4.6 crash: WARNING in sysfs_warn_dup device bridge_slave_0 entered promiscuous mode bridge0: port 2(bridge_slave_1) entered blocking state bridge0: port 2(bridge_slave_1) entered disabled state device bridge_slave_1 entered promiscuous mode ------------[ cut here ]------------ WARNING: CPU: 0 PID: 5931 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: 5931 Comm: syz-executor.3 Not tainted 4.6.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 0000000000000000 ffff8800b9d6efc8 ffffffff82c65932 ffffffff85e81040 ffff8800b9d6f0a0 ffffffff85f2bdc0 ffffffff8191b86b 0000000000000009 ffff8800b9d6f090 ffffffff8160d374 0000000041b58ab3 ffffffff86b12d72 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0x136/0x1d4 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.0+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+0x677/0x1350 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+0x8e8/0xd00 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+0x3da/0x560 net/netlink/af_netlink.c:1240 [] netlink_sendmsg+0x9bb/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 net/socket.c:1648 [inline] [] SyS_sendto+0x1ca/0x290 net/socket.c:1616 [] entry_SYSCALL_64_fastpath+0x23/0xc1 Kernel Offset: disabled