bisecting cause commit starting from 83dadd4cfb0c472ad1b19d05343766018a14a458 building syzkaller on a0234d980eccaa87f5821ac8e95ed9c94a104acf testing commit 83dadd4cfb0c472ad1b19d05343766018a14a458 with gcc (GCC) 8.1.0 kernel signature: bdd2de09e55ba2ff6120e659760d4365fc58e5a24d346db75a6306392e8f6614 all runs: crashed: WARNING in squashfs_read_table testing release v5.10 testing commit 2c85ebc57b3e1817b6ce1a6b703928e113a90442 with gcc (GCC) 8.1.0 kernel signature: 395a614079c9030036488f72c030c4708fae86b9aba956ca15d15003efd3a593 all runs: crashed: WARNING in squashfs_read_table testing release v5.9 testing commit bbf5c979011a099af5dc76498918ed7df445635b with gcc (GCC) 8.1.0 kernel signature: 267e4e72ea6151d6ca484a7d3cc70be89ff7365b860f2a296ca76a677664b0bf all runs: crashed: WARNING in squashfs_read_table testing release v5.8 testing commit bcf876870b95592b52519ed4aafcf9d95999bc9c with gcc (GCC) 8.1.0 kernel signature: e1b748eb2406e6b7622d3ac2ddd4d5444e7de9e64fd85ab34f83bf371b1755d5 all runs: crashed: WARNING in squashfs_read_table testing release v5.7 testing commit 3d77e6a8804abcc0504c904bd6e5cdf3a5cf8162 with gcc (GCC) 8.1.0 kernel signature: 47862bb6707373f5ffcdd61ba6af4294f0c423a6cb2ee4daa5590631048de304 all runs: crashed: WARNING in squashfs_read_table testing release v5.6 testing commit 7111951b8d4973bda27ff663f2cf18b663d15b48 with gcc (GCC) 8.1.0 kernel signature: 61d2f47e590b5f5b9af99913aeee4a183890a5a3a42d33ead5af338d6fce77b0 run #0: crashed: WARNING in squashfs_read_table run #1: crashed: WARNING in squashfs_read_table run #2: crashed: WARNING in squashfs_read_table run #3: crashed: WARNING in squashfs_read_table run #4: crashed: WARNING in squashfs_read_table run #5: crashed: WARNING in squashfs_read_table run #6: crashed: WARNING in squashfs_read_table run #7: crashed: WARNING in squashfs_read_table run #8: crashed: WARNING in squashfs_read_table run #9: boot failed: can't ssh into the instance testing release v5.5 testing commit d5226fa6dbae0569ee43ecfc08bdcd6770fc4755 with gcc (GCC) 8.1.0 kernel signature: c02e30c85a426c1e8f9c3abeaf54f05a4c728b21f645f4db12a4be37adab4f4f all runs: crashed: WARNING in squashfs_read_table testing release v5.4 testing commit 219d54332a09e8d8741c1e1982f5eae56099de85 with gcc (GCC) 8.1.0 kernel signature: 418d776f3a3a1cc9254eb5d6ca3b32cfdd18be0b9d67b015b468405fb2daecff all runs: crashed: WARNING in squashfs_read_table testing release v5.3 testing commit 4d856f72c10ecb060868ed10ff1b1453943fc6c8 with gcc (GCC) 8.1.0 kernel signature: e249628c1ee34f77f2aa319be282abb58f3d9140778e2d153979f2cd76c9b777 all runs: crashed: WARNING in squashfs_read_table testing release v5.2 testing commit 0ecfebd2b52404ae0c54a878c872bb93363ada36 with gcc (GCC) 8.1.0 kernel signature: a6a68d9583d3a8125b02c95fc9622169e78400904b09f46799b9f3c98b341f31 all runs: crashed: WARNING in squashfs_read_table testing release v5.1 testing commit e93c9c99a629c61837d5a7fc2120cd2b6c70dbdd with gcc (GCC) 8.1.0 kernel signature: f8444d7f606701f2cba2c2b1e79ec64e2e00a9604951e8f29c97fd39394d2e63 all runs: crashed: WARNING in squashfs_read_table testing release v5.0 testing commit 1c163f4c7b3f621efff9b28a47abb36f7378d783 with gcc (GCC) 8.1.0 kernel signature: d1de21bb044e544efe5b0b18676c1120101c7d2ac339371f47a9b257538ce7cb all runs: crashed: WARNING in squashfs_read_table testing release v4.20 testing commit 8fe28cb58bcb235034b64cbbb7550a8a43fd88be with gcc (GCC) 8.1.0 kernel signature: bbda2fd3bb8f4be8f780f770d9226da10fff12ad8c60d7075071d084b856b272 all runs: crashed: WARNING in squashfs_read_table testing release v4.19 testing commit 84df9525b0c27f3ebc2ebb1864fa62a97fdedb7d with gcc (GCC) 8.1.0 kernel signature: 49d1c0d58a1b73f22ae88dd8d84d66faeb363a6b3632f71c62820adafe124ec3 all runs: crashed: WARNING in squashfs_read_table testing release v4.18 testing commit 94710cac0ef4ee177a63b5227664b38c95bbf703 with gcc (GCC) 8.1.0 kernel signature: 5b83f437dc7932d520144d2d7de4b79bdf4c1f3f71ab9412862ee30b4d6adc50 all runs: crashed: WARNING in squashfs_read_table testing release v4.17 testing commit 29dcea88779c856c7dc92040a0c01233263101d4 with gcc (GCC) 8.1.0 kernel signature: fb076a9280128373fb20360bfe50eddb3bab0dba5baaa52e3a2f3edc85311ecf all runs: crashed: WARNING in squashfs_read_table testing release v4.16 testing commit 0adb32858b0bddf4ada5f364a84ed60b196dbcda with gcc (GCC) 8.1.0 kernel signature: 1c0f0429d559b9043d8137621bff26350af9503d834215b0e700ce1561d96f3c all runs: crashed: WARNING in squashfs_read_table testing release v4.15 testing commit d8a5b80568a9cb66810e75b182018e9edb68e8ff with gcc (GCC) 8.1.0 kernel signature: 2292c09bfe40ebd2b8d8073dde513defef0f4841cd8d2c7cd73b19e7749cd830 all runs: crashed: WARNING in squashfs_read_table testing release v4.14 testing commit bebc6082da0a9f5d47a1ea2edc099bf671058bd4 with gcc (GCC) 8.1.0 kernel signature: dc0cb55cfef7025cc6cea1320286ea5a66d71724de7ad652aae085824ed838d8 run #0: crashed: WARNING in squashfs_read_table run #1: crashed: WARNING in squashfs_read_table run #2: crashed: WARNING in corrupted run #3: crashed: WARNING in squashfs_read_table run #4: crashed: WARNING in squashfs_read_table run #5: crashed: WARNING in squashfs_read_table run #6: crashed: WARNING in squashfs_read_table run #7: crashed: WARNING in squashfs_read_table run #8: crashed: WARNING in squashfs_read_table run #9: crashed: WARNING in squashfs_read_table testing release v4.13 testing commit 569dbb88e80deb68974ef6fdd6a13edb9d686261 with gcc (GCC) 8.1.0 kernel signature: 921d1d006917767311f4c257579c2910ab0100afc94e6774e6c35521ee5b03a9 all runs: crashed: WARNING in squashfs_read_table testing release v4.12 testing commit 6f7da290413ba713f0cdd9ff1a2a9bb129ef4f6c with gcc (GCC) 8.1.0 kernel signature: b9b41ff1c638e3c965cda086318f566f9189ba0e04f0f0fdc597920dbeefa2e0 all runs: basic kernel testing failed: 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: bd4432bed406c889762cbd7f0b9cb72cf9fa01c98b199a3b2156aa700dc70b12 all runs: basic kernel testing failed: 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: 70fad9a8f7005708add01b6cb56436fb5c29771d181e78826acb76f4e88f4db3 all runs: crashed: WARNING in squashfs_read_table testing release v4.9 testing commit 69973b830859bc6529a7a0468ba0d80ee5117826 with gcc (GCC) 5.5.0 kernel signature: 925145d773d61c1e1e3cfb41b56b7611d111513f17f9da164ea846b8e9f5fe7d run #0: crashed: WARNING in squashfs_read_table run #1: crashed: WARNING in squashfs_read_table run #2: crashed: WARNING in squashfs_read_table run #3: crashed: WARNING in squashfs_read_table run #4: crashed: WARNING in squashfs_read_table run #5: crashed: WARNING in squashfs_read_table run #6: crashed: WARNING in corrupted run #7: crashed: WARNING in squashfs_read_table run #8: crashed: WARNING in squashfs_read_table run #9: crashed: WARNING in squashfs_read_table testing release v4.8 testing commit c8d2bc9bc39ebea8437fd974fdbc21847bb897a3 with gcc (GCC) 5.5.0 kernel signature: 722ee71d760bebe44d8d96975e691bb99ab29ba244cf29f89c1a78dc61b49d9e all runs: crashed: WARNING in squashfs_read_table testing release v4.7 testing commit 523d939ef98fd712632d93a5a2b588e477a7565e with gcc (GCC) 5.5.0 kernel signature: 3ca7d6cb74a092e87999fed63beee3b37dfae7a7fe66d8b51b7673bf688c1181 run #0: crashed: WARNING in alloc_kmem_pages run #1: crashed: WARNING in alloc_kmem_pages run #2: crashed: WARNING in corrupted run #3: crashed: WARNING in alloc_kmem_pages run #4: crashed: WARNING in corrupted run #5: crashed: WARNING in alloc_kmem_pages run #6: crashed: WARNING in corrupted run #7: crashed: WARNING in alloc_kmem_pages run #8: crashed: WARNING in alloc_kmem_pages run #9: crashed: WARNING in alloc_kmem_pages testing release v4.6 testing commit 2dcd0af568b0cf583645c8a317dd12e344b1c72a with gcc (GCC) 5.5.0 kernel signature: e30709e2c4a853849d1da12f0f3b0580f8f32f34dd330639faa3f40d4b8d3175 all runs: crashed: WARNING in sysfs_warn_dup revisions tested: 27, total time: 3h45m14.086476257s (build: 2h18m0.960978319s, test: 1h23m5.843628139s) 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 bridge0: port 1(bridge_slave_0) entered blocking state bridge0: port 1(bridge_slave_0) entered disabled state device bridge_slave_0 entered promiscuous mode ------------[ cut here ]------------ WARNING: CPU: 0 PID: 7914 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: 7914 Comm: syz-executor.4 Not tainted 4.6.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 0000000000000000 ffff8800b2556fc8 ffffffff82dab352 ffffffff8667aec0 ffff8800b25570a0 ffffffff8672c880 ffffffff818db72b 0000000000000009 ffff8800b2557090 ffffffff815c7a54 0000000041b58ab3 ffffffff8777b6e3 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+0x6a1/0x1400 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