bisecting cause commit starting from f40ddce88593482919761f74910f42f4b84c004b building syzkaller on 98682e5e2aefc9aad61354f4f3ac93be96002a2a testing commit f40ddce88593482919761f74910f42f4b84c004b with gcc (GCC) 10.2.1 20210217 kernel signature: 31380acbde5081ebcc03b8b1cc92921ed4a81eb7f97a79d4e8ce6ac16d2b8953 run #0: crashed: INFO: task hung in addrconf_dad_work run #1: crashed: INFO: task hung in linkwatch_event run #2: crashed: INFO: task hung in linkwatch_event run #3: crashed: INFO: task hung in addrconf_dad_work run #4: crashed: INFO: task hung in linkwatch_event run #5: crashed: INFO: task hung in linkwatch_event run #6: crashed: INFO: task hung in addrconf_dad_work run #7: crashed: INFO: task hung in addrconf_dad_work run #8: crashed: INFO: task hung in addrconf_dad_work run #9: crashed: INFO: task hung in addrconf_dad_work testing release v5.10 testing commit 2c85ebc57b3e1817b6ce1a6b703928e113a90442 with gcc (GCC) 10.2.1 20210217 kernel signature: 07832ad157a2f1ad292c1f7361e44f05f5f1a63f52599ba6ca147467259ef5f8 run #0: crashed: INFO: task hung in addrconf_dad_work run #1: crashed: INFO: task hung in addrconf_dad_work run #2: crashed: INFO: task hung in linkwatch_event run #3: crashed: INFO: task hung in addrconf_dad_work run #4: crashed: INFO: task hung in linkwatch_event run #5: crashed: INFO: task hung in disconnect_work run #6: crashed: INFO: task hung in addrconf_dad_work run #7: crashed: INFO: task hung in disconnect_work run #8: boot failed: can't ssh into the instance run #9: crashed: INFO: task hung in disconnect_work testing release v5.9 testing commit bbf5c979011a099af5dc76498918ed7df445635b with gcc (GCC) 10.2.1 20210217 kernel signature: 4982d648f34b34a14f5d14be196adc9606eea9098e868e858a5fcadcd19f17d4 run #0: crashed: INFO: task hung in disconnect_work run #1: crashed: INFO: task hung in disconnect_work run #2: crashed: INFO: task hung in linkwatch_event run #3: crashed: INFO: task hung in addrconf_dad_work run #4: crashed: INFO: task hung in linkwatch_event run #5: crashed: INFO: task hung in disconnect_work run #6: crashed: INFO: task hung in cfg80211_dfs_channels_update_work run #7: crashed: INFO: task hung in addrconf_dad_work run #8: crashed: INFO: task hung in addrconf_dad_work run #9: crashed: INFO: task hung in disconnect_work testing release v5.8 testing commit bcf876870b95592b52519ed4aafcf9d95999bc9c with gcc (GCC) 8.4.1 20210217 kernel signature: 7846484ba3fe701bdfa7fc4a606543fc283b3f1fe345bf1330247f6e4ec67c28 run #0: crashed: INFO: task hung in disconnect_work run #1: crashed: INFO: task hung in cfg80211_event_work run #2: crashed: INFO: task hung in addrconf_dad_work run #3: crashed: INFO: task hung in addrconf_dad_work run #4: crashed: INFO: task hung in addrconf_dad_work run #5: crashed: INFO: task hung in addrconf_dad_work run #6: crashed: INFO: task hung in linkwatch_event run #7: crashed: INFO: task hung in disconnect_work run #8: crashed: INFO: task hung in addrconf_dad_work run #9: crashed: INFO: task hung in cfg80211_event_work testing release v5.7 testing commit 3d77e6a8804abcc0504c904bd6e5cdf3a5cf8162 with gcc (GCC) 8.4.1 20210217 kernel signature: 453cc8c1a9c35695c2777696601bb7f33aad2f0c2fe8676187d33203af0eb1a3 run #0: crashed: INFO: task hung in addrconf_dad_work run #1: crashed: INFO: task hung in disconnect_work run #2: crashed: INFO: task hung in addrconf_dad_work run #3: crashed: INFO: task hung in linkwatch_event run #4: crashed: INFO: task hung in addrconf_dad_work run #5: crashed: INFO: task hung in addrconf_dad_work run #6: crashed: INFO: task hung in linkwatch_event run #7: crashed: INFO: task hung in disconnect_work run #8: crashed: INFO: task hung in disconnect_work run #9: crashed: INFO: task hung in addrconf_dad_work testing release v5.6 testing commit 7111951b8d4973bda27ff663f2cf18b663d15b48 with gcc (GCC) 8.4.1 20210217 kernel signature: 27f1b82998d6e62f6ee66b52d34d74089d8c75235cac14df8ce965fb9a84ea76 run #0: crashed: INFO: task hung in cfg80211_dfs_channels_update_work run #1: crashed: INFO: task hung in addrconf_dad_work run #2: crashed: INFO: task hung in addrconf_dad_work run #3: crashed: INFO: task hung in disconnect_work run #4: crashed: INFO: task hung in cfg80211_event_work run #5: crashed: INFO: task hung in disconnect_work run #6: crashed: INFO: task hung in cfg80211_event_work run #7: crashed: INFO: task hung in cfg80211_event_work run #8: crashed: INFO: task hung in addrconf_dad_work run #9: crashed: INFO: task hung in cfg80211_event_work testing release v5.5 testing commit d5226fa6dbae0569ee43ecfc08bdcd6770fc4755 with gcc (GCC) 8.4.1 20210217 kernel signature: 4658d923f6cfd96c8464cf31e576b941762bd165afa96d62622c7e614efce4d0 run #0: crashed: INFO: task hung in addrconf_dad_work run #1: crashed: INFO: task hung in addrconf_dad_work run #2: crashed: INFO: task hung in addrconf_dad_work run #3: crashed: INFO: task hung in disconnect_work run #4: crashed: INFO: task hung in addrconf_dad_work run #5: crashed: INFO: task hung in addrconf_dad_work run #6: crashed: INFO: task hung in linkwatch_event run #7: crashed: INFO: task hung in cfg80211_event_work run #8: crashed: INFO: task hung in addrconf_dad_work run #9: crashed: INFO: task hung in addrconf_dad_work testing release v5.4 testing commit 219d54332a09e8d8741c1e1982f5eae56099de85 with gcc (GCC) 8.4.1 20210217 kernel signature: 953d9d5c3e1824ebeebc8bdd2ce0c7fdeb53d99721f09336d6ea085ba3c0d6f0 run #0: crashed: INFO: task hung in addrconf_dad_work run #1: crashed: INFO: task hung in linkwatch_event run #2: crashed: INFO: task hung in disconnect_work run #3: crashed: INFO: task hung in addrconf_dad_work run #4: crashed: INFO: task hung in addrconf_dad_work run #5: crashed: INFO: task hung in addrconf_dad_work run #6: crashed: INFO: task hung in addrconf_dad_work run #7: crashed: INFO: task hung in cfg80211_event_work run #8: crashed: INFO: task hung in addrconf_dad_work run #9: crashed: INFO: task hung in addrconf_dad_work testing release v5.3 testing commit 4d856f72c10ecb060868ed10ff1b1453943fc6c8 with gcc (GCC) 8.4.1 20210217 kernel signature: 4112a685bfabeaae5cf8f1e839be53e8c9d17ef9c2fdd077033ccdcd123c98b8 all runs: boot failed: BUG: spinlock bad magic in nf_connlabels_get testing release v5.2 testing commit 0ecfebd2b52404ae0c54a878c872bb93363ada36 with gcc (GCC) 8.4.1 20210217 kernel signature: 74c2bc6782e144f6d25cfb12fb3a974f58ae03605a2e3b02d0169d6572ecfb43 all runs: boot failed: can't ssh into the instance testing release v5.1 testing commit e93c9c99a629c61837d5a7fc2120cd2b6c70dbdd with gcc (GCC) 8.4.1 20210217 kernel signature: c7eefb4ce691d2bda2f9eea810f058d346ccec9ef1d23a24c4ae6e4278c86cf4 all runs: boot failed: can't ssh into the instance testing release v5.0 testing commit 1c163f4c7b3f621efff9b28a47abb36f7378d783 with gcc (GCC) 8.4.1 20210217 kernel signature: ecf2e981e70a1e450b2c5688676eb627ac10cb1aaf1914c1daaeeda23eaf3846 all runs: boot failed: can't ssh into the instance testing release v4.20 testing commit 8fe28cb58bcb235034b64cbbb7550a8a43fd88be with gcc (GCC) 8.4.1 20210217 kernel signature: f4fb86f1ba47e1e5d288e676b45e9a7bd81227a7cc5d7ed1c29d5f441d356ec0 all runs: boot failed: can't ssh into the instance testing release v4.19 testing commit 84df9525b0c27f3ebc2ebb1864fa62a97fdedb7d with gcc (GCC) 8.4.1 20210217 kernel signature: ec9930eaff6a2a42b7ad9ac488b5ab8561336aa9bdb402ddb5b0e0b347a6b2b9 all runs: boot failed: can't ssh into the instance testing release v4.18 testing commit 94710cac0ef4ee177a63b5227664b38c95bbf703 with gcc (GCC) 8.4.1 20210217 kernel signature: 375bfb615b86d4d3d1630d7d79a717637184a3828c86cd8aad648635789c1293 all runs: boot failed: can't ssh into the instance testing release v4.17 testing commit 29dcea88779c856c7dc92040a0c01233263101d4 with gcc (GCC) 8.4.1 20210217 ./security/selinux/include/classmap.h:247:2: error: #error New address family defined, please update secclass_map. testing release v4.16 testing commit 0adb32858b0bddf4ada5f364a84ed60b196dbcda with gcc (GCC) 8.4.1 20210217 ./security/selinux/include/classmap.h:247:2: error: #error New address family defined, please update secclass_map. orc_dump.c:106:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] orc_dump.c:111:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] elf.c:135:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:140:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] testing release v4.15 testing commit d8a5b80568a9cb66810e75b182018e9edb68e8ff with gcc (GCC) 8.4.1 20210217 orc_dump.c:106:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] orc_dump.c:111:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:36:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] elf.c:135:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:140:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] ./security/selinux/include/classmap.h:247:2: error: #error New address family defined, please update secclass_map. testing release v4.14 testing commit bebc6082da0a9f5d47a1ea2edc099bf671058bd4 with gcc (GCC) 8.4.1 20210217 orc_dump.c:105:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] orc_dump.c:110:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:36:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] elf.c:134:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:139:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] ./security/selinux/include/classmap.h:245:2: error: #error New address family defined, please update secclass_map. testing release v4.13 testing commit 569dbb88e80deb68974ef6fdd6a13edb9d686261 with gcc (GCC) 8.4.1 20210217 pager.c:35:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] elf.c:144:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:149:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] ./security/selinux/include/classmap.h:242:2: error: #error New address family defined, please update secclass_map. testing release v4.12 testing commit 6f7da290413ba713f0cdd9ff1a2a9bb129ef4f6c with gcc (GCC) 8.4.1 20210217 pager.c:35:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] elf.c:141:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:146:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] ./security/selinux/include/classmap.h:238:2: error: #error New address family defined, please update secclass_map. testing release v4.11 testing commit a351e9b9fc24e982ec2f0e76379a49826036da12 with gcc (GCC) 7.5.0 elf.c:141:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:146:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:35:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] testing release v4.10 testing commit c470abd4fde40ea6a0846a2beab642a578c0b8cd with gcc (GCC) 5.5.0 tools/include/linux/log2.h:19:1: error: ignoring attribute 'noreturn' because it conflicts with attribute 'const' [-Werror=attributes] elf.c:129:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:134:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:35:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] testing release v4.9 testing commit 69973b830859bc6529a7a0468ba0d80ee5117826 with gcc (GCC) 5.5.0 tools/include/linux/log2.h:19:1: error: ignoring attribute 'noreturn' because it conflicts with attribute 'const' [-Werror=attributes] elf.c:129:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:134:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:35:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] testing release v4.8 testing commit c8d2bc9bc39ebea8437fd974fdbc21847bb897a3 with gcc (GCC) 5.5.0 tools/include/linux/log2.h:19:1: error: ignoring attribute 'noreturn' because it conflicts with attribute 'const' [-Werror=attributes] elf.c:129:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:134:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:33:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] testing release v4.7 testing commit 523d939ef98fd712632d93a5a2b588e477a7565e with gcc (GCC) 5.5.0 tools/include/linux/log2.h:19:1: error: ignoring attribute 'noreturn' because it conflicts with attribute 'const' [-Werror=attributes] elf.c:122:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:127:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:33:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] testing release v4.6 testing commit 2dcd0af568b0cf583645c8a317dd12e344b1c72a with gcc (GCC) 5.5.0 tools/include/linux/log2.h:19:1: error: ignoring attribute 'noreturn' because it conflicts with attribute 'const' [-Werror=attributes] pager.c:33:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] revisions tested: 15, total time: 3h51m20.144226516s (build: 1h38m42.587837582s, test: 2h4m10.316021991s) the crash already happened on the oldest tested release commit msg: Linux 5.4 crash: INFO: task hung in addrconf_dad_work INFO: task kworker/1:0:17 blocked for more than 143 seconds. Not tainted 5.4.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:0 D25656 17 2 0x80004000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: schedule+0xc1/0x260 kernel/sched/core.c:4145 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4204 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x8e5/0x1400 kernel/locking/mutex.c:1103 addrconf_dad_work+0xa1/0x1000 net/ipv6/addrconf.c:4033 process_one_work+0x8ca/0x16c0 kernel/workqueue.c:2269 worker_thread+0x82/0xb50 kernel/workqueue.c:2415 kthread+0x31d/0x3e0 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task kworker/1:1:22 blocked for more than 143 seconds. Not tainted 5.4.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:1 D28240 22 2 0x80004000 Workqueue: events linkwatch_event Call Trace: schedule+0xc1/0x260 kernel/sched/core.c:4145 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4204 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x8e5/0x1400 kernel/locking/mutex.c:1103 linkwatch_event+0x5/0x50 net/core/link_watch.c:242 process_one_work+0x8ca/0x16c0 kernel/workqueue.c:2269 worker_thread+0x82/0xb50 kernel/workqueue.c:2415 kthread+0x31d/0x3e0 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task kworker/0:2:3726 blocked for more than 143 seconds. Not tainted 5.4.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:2 D26448 3726 2 0x80004000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: schedule+0xc1/0x260 kernel/sched/core.c:4145 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4204 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x8e5/0x1400 kernel/locking/mutex.c:1103 addrconf_dad_work+0xa1/0x1000 net/ipv6/addrconf.c:4033 process_one_work+0x8ca/0x16c0 kernel/workqueue.c:2269 worker_thread+0x82/0xb50 kernel/workqueue.c:2415 kthread+0x31d/0x3e0 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task kworker/1:3:4884 blocked for more than 144 seconds. Not tainted 5.4.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:3 D26040 4884 2 0x80004000 Workqueue: events disconnect_work Call Trace: schedule+0xc1/0x260 kernel/sched/core.c:4145 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4204 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x8e5/0x1400 kernel/locking/mutex.c:1103 disconnect_work+0xf/0x1b0 net/wireless/sme.c:664 process_one_work+0x8ca/0x16c0 kernel/workqueue.c:2269 worker_thread+0x82/0xb50 kernel/workqueue.c:2415 kthread+0x31d/0x3e0 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task syz-executor.2:8677 blocked for more than 144 seconds. Not tainted 5.4.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D24992 8677 1 0x00000004 Call Trace: schedule+0xc1/0x260 kernel/sched/core.c:4145 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4204 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x8e5/0x1400 kernel/locking/mutex.c:1103 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x30a/0x8d0 net/core/rtnetlink.c:5242 netlink_rcv_skb+0x119/0x340 net/netlink/af_netlink.c:2477 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x3fc/0x5c0 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x71e/0xb70 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:657 __sys_sendto+0x1d3/0x2b0 net/socket.c:1952 __do_sys_sendto net/socket.c:1964 [inline] __se_sys_sendto net/socket.c:1960 [inline] __x64_sys_sendto+0xd8/0x1b0 net/socket.c:1960 do_syscall_64+0x8e/0x4e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x41922c Code: Bad RIP value. RSP: 002b:00007ffe1919a780 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00000000014a4320 RCX: 000000000041922c RDX: 0000000000000020 RSI: 00000000014a4370 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffe1919a7c4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000000 R15: 00000000014a4370 INFO: task syz-executor.4:8682 blocked for more than 144 seconds. Not tainted 5.4.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D24992 8682 1 0x00000004 Call Trace: schedule+0xc1/0x260 kernel/sched/core.c:4145 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4204 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x8e5/0x1400 kernel/locking/mutex.c:1103 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x30a/0x8d0 net/core/rtnetlink.c:5242 netlink_rcv_skb+0x119/0x340 net/netlink/af_netlink.c:2477 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x3fc/0x5c0 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x71e/0xb70 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:657 __sys_sendto+0x1d3/0x2b0 net/socket.c:1952 __do_sys_sendto net/socket.c:1964 [inline] __se_sys_sendto net/socket.c:1960 [inline] __x64_sys_sendto+0xd8/0x1b0 net/socket.c:1960 do_syscall_64+0x8e/0x4e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x41922c Code: Bad RIP value. RSP: 002b:00007ffd425f87f0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00000000014a4320 RCX: 000000000041922c RDX: 0000000000000040 RSI: 00000000014a4370 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffd425f8834 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000000 R15: 00000000014a4370 INFO: task syz-executor.0:10260 blocked for more than 145 seconds. Not tainted 5.4.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28760 10260 8681 0x00000004 Call Trace: schedule+0xc1/0x260 kernel/sched/core.c:4145 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4204 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x8e5/0x1400 kernel/locking/mutex.c:1103 nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 genl_family_rcv_msg+0x5d8/0xf40 net/netlink/genetlink.c:624 genl_rcv_msg+0xb3/0x160 net/netlink/genetlink.c:654 netlink_rcv_skb+0x119/0x340 net/netlink/af_netlink.c:2477 genl_rcv+0x1f/0x30 net/netlink/genetlink.c:665 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x3fc/0x5c0 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x71e/0xb70 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:657 ___sys_sendmsg+0x653/0x950 net/socket.c:2311 __sys_sendmsg+0xce/0x170 net/socket.c:2356 do_syscall_64+0x8e/0x4e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465d99 Code: Bad RIP value. RSP: 002b:00007f3973573188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000056c0b0 RCX: 0000000000465d99 RDX: 0000000000000000 RSI: 0000000020000340 RDI: 0000000000000003 RBP: 00000000004bcf27 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c0b0 R13: 00007ffe9f2c7cef R14: 00007f3973573300 R15: 0000000000022000 INFO: task syz-executor.3:10265 blocked for more than 145 seconds. Not tainted 5.4.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28088 10265 8674 0x00000004 Call Trace: schedule+0xc1/0x260 kernel/sched/core.c:4145 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4204 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x8e5/0x1400 kernel/locking/mutex.c:1103 nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 genl_family_rcv_msg+0x5d8/0xf40 net/netlink/genetlink.c:624 genl_rcv_msg+0xb3/0x160 net/netlink/genetlink.c:654 netlink_rcv_skb+0x119/0x340 net/netlink/af_netlink.c:2477 genl_rcv+0x1f/0x30 net/netlink/genetlink.c:665 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x3fc/0x5c0 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x71e/0xb70 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:657 ___sys_sendmsg+0x653/0x950 net/socket.c:2311 __sys_sendmsg+0xce/0x170 net/socket.c:2356 do_syscall_64+0x8e/0x4e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465d99 Code: Bad RIP value. RSP: 002b:00007ff50eea4188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465d99 RDX: 0000000000000000 RSI: 0000000020000340 RDI: 0000000000000003 RBP: 00000000004bcf27 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007fff96dea49f R14: 00007ff50eea4300 R15: 0000000000022000 INFO: task syz-executor.3:10271 blocked for more than 146 seconds. Not tainted 5.4.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28760 10271 8674 0x00004004 Call Trace: schedule+0xc1/0x260 kernel/sched/core.c:4145 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4204 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x8e5/0x1400 kernel/locking/mutex.c:1103 nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 genl_family_rcv_msg+0x5d8/0xf40 net/netlink/genetlink.c:624 genl_rcv_msg+0xb3/0x160 net/netlink/genetlink.c:654 netlink_rcv_skb+0x119/0x340 net/netlink/af_netlink.c:2477 genl_rcv+0x1f/0x30 net/netlink/genetlink.c:665 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x3fc/0x5c0 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x71e/0xb70 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:657 ___sys_sendmsg+0x653/0x950 net/socket.c:2311 __sys_sendmsg+0xce/0x170 net/socket.c:2356 do_syscall_64+0x8e/0x4e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465d99 Code: Bad RIP value. RSP: 002b:00007ff50ee83188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000056c008 RCX: 0000000000465d99 RDX: 0000000004000004 RSI: 00000000200000c0 RDI: 0000000000000005 RBP: 00000000004bcf27 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c008 R13: 00007fff96dea49f R14: 00007ff50ee83300 R15: 0000000000022000 INFO: task syz-executor.3:10277 blocked for more than 146 seconds. Not tainted 5.4.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28760 10277 8674 0x00000004 Call Trace: schedule+0xc1/0x260 kernel/sched/core.c:4145 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4204 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x8e5/0x1400 kernel/locking/mutex.c:1103 nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 genl_family_rcv_msg+0x5d8/0xf40 net/netlink/genetlink.c:624 genl_rcv_msg+0xb3/0x160 net/netlink/genetlink.c:654 netlink_rcv_skb+0x119/0x340 net/netlink/af_netlink.c:2477 genl_rcv+0x1f/0x30 net/netlink/genetlink.c:665 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x3fc/0x5c0 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x71e/0xb70 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:657 ___sys_sendmsg+0x653/0x950 net/socket.c:2311 __sys_sendmsg+0xce/0x170 net/socket.c:2356 do_syscall_64+0x8e/0x4e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465d99 Code: Bad RIP value. RSP: 002b:00007ff50ee62188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000056c0b0 RCX: 0000000000465d99 RDX: 0000000000000000 RSI: 0000000020000340 RDI: 0000000000000003 RBP: 00000000004bcf27 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c0b0 R13: 00007fff96dea49f R14: 00007ff50ee62300 R15: 0000000000022000 Showing all locks held in the system: 3 locks held by kworker/1:0/17: #0: ffff8880a57cb128 ((wq_completion)ipv6_addrconf){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880a57cb128 ((wq_completion)ipv6_addrconf){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880a57cb128 ((wq_completion)ipv6_addrconf){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880a57cb128 ((wq_completion)ipv6_addrconf){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880a57cb128 ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff8880a57cb128 ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff8880a57cb128 ((wq_completion)ipv6_addrconf){+.+.}, at: process_one_work+0x7dd/0x16c0 kernel/workqueue.c:2240 #1: ffff8880b4d37e00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}, at: process_one_work+0x811/0x16c0 kernel/workqueue.c:2244 #2: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: addrconf_dad_work+0xa1/0x1000 net/ipv6/addrconf.c:4033 3 locks held by kworker/1:1/22: #0: ffff8880b5827d28 ((wq_completion)events){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880b5827d28 ((wq_completion)events){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880b5827d28 ((wq_completion)events){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880b5827d28 ((wq_completion)events){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880b5827d28 ((wq_completion)events){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff8880b5827d28 ((wq_completion)events){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff8880b5827d28 ((wq_completion)events){+.+.}, at: process_one_work+0x7dd/0x16c0 kernel/workqueue.c:2240 #1: ffff8880b4edfe00 ((linkwatch_work).work){+.+.}, at: process_one_work+0x811/0x16c0 kernel/workqueue.c:2244 #2: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: linkwatch_event+0x5/0x50 net/core/link_watch.c:242 1 lock held by khungtaskd/1565: #0: ffffffff8a0cb2c0 (rcu_read_lock){....}, at: debug_show_all_locks+0x52/0x2be kernel/locking/lockdep.c:5335 3 locks held by kworker/0:2/3726: #0: ffff8880a57cb128 ((wq_completion)ipv6_addrconf){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880a57cb128 ((wq_completion)ipv6_addrconf){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880a57cb128 ((wq_completion)ipv6_addrconf){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880a57cb128 ((wq_completion)ipv6_addrconf){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880a57cb128 ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff8880a57cb128 ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff8880a57cb128 ((wq_completion)ipv6_addrconf){+.+.}, at: process_one_work+0x7dd/0x16c0 kernel/workqueue.c:2240 #1: ffff8880a9f47e00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}, at: process_one_work+0x811/0x16c0 kernel/workqueue.c:2244 #2: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: addrconf_dad_work+0xa1/0x1000 net/ipv6/addrconf.c:4033 3 locks held by kworker/1:3/4884: #0: ffff8880b5827d28 ((wq_completion)events){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880b5827d28 ((wq_completion)events){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880b5827d28 ((wq_completion)events){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880b5827d28 ((wq_completion)events){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880b5827d28 ((wq_completion)events){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff8880b5827d28 ((wq_completion)events){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff8880b5827d28 ((wq_completion)events){+.+.}, at: process_one_work+0x7dd/0x16c0 kernel/workqueue.c:2240 #1: ffff8880aa1f7e00 (cfg80211_disconnect_work){+.+.}, at: process_one_work+0x811/0x16c0 kernel/workqueue.c:2244 #2: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: disconnect_work+0xf/0x1b0 net/wireless/sme.c:664 1 lock held by in:imklog/8175: #0: ffff8880b47b3da0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x96/0xb0 fs/file.c:801 1 lock held by syz-executor.2/8677: #0: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x30a/0x8d0 net/core/rtnetlink.c:5242 1 lock held by syz-executor.4/8682: #0: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x30a/0x8d0 net/core/rtnetlink.c:5242 3 locks held by kworker/1:4/10040: #0: ffff8880b5836128 ((wq_completion)events_power_efficient){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880b5836128 ((wq_completion)events_power_efficient){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880b5836128 ((wq_completion)events_power_efficient){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880b5836128 ((wq_completion)events_power_efficient){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880b5836128 ((wq_completion)events_power_efficient){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff8880b5836128 ((wq_completion)events_power_efficient){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff8880b5836128 ((wq_completion)events_power_efficient){+.+.}, at: process_one_work+0x7dd/0x16c0 kernel/workqueue.c:2240 #1: ffff8880a1e6fe00 ((reg_check_chans).work){+.+.}, at: process_one_work+0x811/0x16c0 kernel/workqueue.c:2244 #2: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: reg_check_chans_work+0x74/0xb60 net/wireless/reg.c:2196 3 locks held by syz-executor.0/10256: 2 locks held by syz-executor.0/10260: #0: ffffffff8bd673e8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 net/netlink/genetlink.c:664 #1: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 2 locks held by syz-executor.3/10265: #0: ffffffff8bd673e8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 net/netlink/genetlink.c:664 #1: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 2 locks held by syz-executor.3/10271: #0: ffffffff8bd673e8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 net/netlink/genetlink.c:664 #1: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 2 locks held by syz-executor.3/10277: #0: ffffffff8bd673e8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 net/netlink/genetlink.c:664 #1: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 2 locks held by syz-executor.3/10280: #0: ffffffff8bd673e8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 net/netlink/genetlink.c:664 #1: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 2 locks held by syz-executor.3/10281: #0: ffffffff8bd673e8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 net/netlink/genetlink.c:664 #1: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 2 locks held by syz-executor.3/10282: #0: ffffffff8bd673e8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 net/netlink/genetlink.c:664 #1: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 2 locks held by syz-executor.5/10266: #0: ffffffff8bd673e8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 net/netlink/genetlink.c:664 #1: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 2 locks held by syz-executor.5/10273: #0: ffffffff8bd673e8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 net/netlink/genetlink.c:664 #1: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 2 locks held by syz-executor.5/10278: #0: ffffffff8bd673e8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 net/netlink/genetlink.c:664 #1: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 2 locks held by syz-executor.5/10283: #0: ffffffff8bd673e8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 net/netlink/genetlink.c:664 #1: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 2 locks held by syz-executor.5/10284: #0: ffffffff8bd673e8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 net/netlink/genetlink.c:664 #1: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 2 locks held by syz-executor.5/10286: #0: ffffffff8bd673e8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 net/netlink/genetlink.c:664 #1: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 2 locks held by syz-executor.1/10267: #0: ffffffff8bd673e8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 net/netlink/genetlink.c:664 #1: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 2 locks held by syz-executor.1/10272: #0: ffffffff8bd673e8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 net/netlink/genetlink.c:664 #1: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 2 locks held by syz-executor.1/10279: #0: ffffffff8bd673e8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 net/netlink/genetlink.c:664 #1: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 2 locks held by syz-executor.1/10285: #0: ffffffff8bd673e8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 net/netlink/genetlink.c:664 #1: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 2 locks held by syz-executor.1/10287: #0: ffffffff8bd673e8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 net/netlink/genetlink.c:664 #1: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 2 locks held by syz-executor.1/10288: #0: ffffffff8bd673e8 (cb_lock){++++}, at: genl_rcv+0x10/0x30 net/netlink/genetlink.c:664 #1: ffffffff8bcae280 (rtnl_mutex){+.+.}, at: nl80211_pre_doit+0x27b/0x500 net/wireless/nl80211.c:13814 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1565 Comm: khungtaskd Not tainted 5.4.0-syzkaller #0 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+0x96/0xe0 lib/dump_stack.c:118 nmi_cpu_backtrace.cold.6+0x2e/0x33 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x183/0x1ac lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0x6e7/0xce0 kernel/hung_task.c:289 kthread+0x31d/0x3e0 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 1533 Comm: kworker/u4:4 Not tainted 5.4.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_tt_purge RIP: 0010:__preempt_count_sub arch/x86/include/asm/preempt.h:84 [inline] RIP: 0010:preempt_count_sub+0x59/0x140 kernel/sched/core.c:3821 Code: 85 ea 00 00 00 8b 0d 26 c4 e0 0c 85 c9 75 1b 65 8b 05 83 e1 bd 7e 89 c2 81 e2 ff ff ff 7f 39 d3 7f 13 81 fb fe 00 00 00 76 66 db 65 01 1d 66 e1 bd 7e 5b c3 e8 07 e5 24 02 85 c0 74 f5 48 c7 RSP: 0018:ffff8880b26b7ce0 EFLAGS: 00000002 RAX: 0000000080000001 RBX: 0000000000000001 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffffffff8e24d220 RBP: ffffffff87d3ab40 R08: 0000000000000001 R09: ffffed1012dc03ea R10: ffffed1012dc03e9 R11: ffff888096e01f4b R12: ffff8880b25e6700 R13: ffff888093fd11b8 R14: ffff8880a9665f40 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb955e8c020 CR3: 00000000b371a000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __local_bh_enable_ip+0x118/0x1d0 kernel/softirq.c:192 spin_unlock_bh include/linux/spinlock.h:383 [inline] batadv_tt_global_purge net/batman-adv/translation-table.c:2531 [inline] batadv_tt_purge+0x260/0xa60 net/batman-adv/translation-table.c:3802 process_one_work+0x8ca/0x16c0 kernel/workqueue.c:2269 worker_thread+0x82/0xb50 kernel/workqueue.c:2415 kthread+0x31d/0x3e0 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352