bisecting fixing commit since fc3abb53250a90ba2150eebd182137c136f4d25a building syzkaller on abf9ba4fc75d9b29af15625d44dcfc1360fad3b7 testing commit fc3abb53250a90ba2150eebd182137c136f4d25a with gcc (GCC) 8.4.1 20210217 kernel signature: 2d171b5e99cc1e86f328ad10335be5d24c0cdee9cf72ab9f90479e8592770217 run #0: crashed: BUG: soft lockup in smp_call_function run #1: crashed: BUG: soft lockup in rtnl_newlink run #2: crashed: BUG: soft lockup in rtnl_newlink run #3: crashed: BUG: soft lockup in do_idle run #4: crashed: BUG: soft lockup in do_idle run #5: crashed: BUG: soft lockup in do_idle run #6: crashed: BUG: soft lockup in do_idle run #7: crashed: BUG: soft lockup in do_idle run #8: crashed: BUG: workqueue lockup run #9: crashed: BUG: soft lockup in do_idle run #10: crashed: BUG: workqueue lockup run #11: crashed: BUG: soft lockup in newlstat run #12: crashed: BUG: workqueue lockup run #13: crashed: BUG: soft lockup in linkwatch_event run #14: crashed: BUG: workqueue lockup run #15: crashed: BUG: soft lockup in do_idle run #16: crashed: BUG: soft lockup in do_idle run #17: crashed: BUG: workqueue lockup run #18: crashed: BUG: soft lockup in do_idle run #19: crashed: BUG: soft lockup in do_idle testing current HEAD 17ae69aba89dbfa2139b7f8024b757ab3cc42f59 testing commit 17ae69aba89dbfa2139b7f8024b757ab3cc42f59 with gcc (GCC) 10.2.1 20210217 kernel signature: ef857d65c4d84760bee16e5b4398c2802ea9c6bb50252ebab9622f30683727d7 run #0: crashed: BUG: soft lockup in tc_modify_qdisc run #1: crashed: BUG: soft lockup in do_idle run #2: crashed: BUG: soft lockup in inet_rtm_newaddr run #3: crashed: BUG: soft lockup in do_idle run #4: crashed: BUG: soft lockup in mutex_spin_on_owner run #5: crashed: BUG: soft lockup in tc_modify_qdisc run #6: crashed: BUG: soft lockup in do_idle run #7: crashed: BUG: workqueue lockup run #8: crashed: BUG: soft lockup in rtnl_newlink run #9: crashed: BUG: soft lockup in linkwatch_event revisions tested: 2, total time: 24m55.041147811s (build: 13m1.164777173s, test: 11m1.303911135s) the crash still happens on HEAD commit msg: Merge tag 'landlock_v34' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security crash: BUG: soft lockup in linkwatch_event watchdog: BUG: soft lockup - CPU#1 stuck for 64s! [kworker/1:0:19] Modules linked in: irq event stamp: 28680 hardirqs last enabled at (28679): [] console_unlock+0x7c0/0x9c0 kernel/printk/printk.c:2651 hardirqs last disabled at (28680): [] sysvec_apic_timer_interrupt+0xb/0xc0 arch/x86/kernel/apic/apic.c:1100 softirqs last enabled at (28672): [] spin_unlock_bh include/linux/spinlock.h:399 [inline] softirqs last enabled at (28672): [] clusterip_netdev_event+0x369/0x540 net/ipv4/netfilter/ipt_CLUSTERIP.c:222 softirqs last disabled at (28670): [] spin_lock_bh include/linux/spinlock.h:359 [inline] softirqs last disabled at (28670): [] clusterip_netdev_event+0x13e/0x540 net/ipv4/netfilter/ipt_CLUSTERIP.c:196 CPU: 1 PID: 19 Comm: kworker/1:0 Not tainted 5.12.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events linkwatch_event RIP: 0010:arch_local_irq_enable arch/x86/include/asm/paravirt.h:695 [inline] RIP: 0010:arch_local_irq_restore arch/x86/include/asm/irqflags.h:140 [inline] RIP: 0010:console_unlock+0x7ea/0x9c0 kernel/printk/printk.c:2651 Code: 48 c7 c0 80 41 37 89 48 c1 e8 03 80 3c 18 00 0f 85 62 01 00 00 48 83 3d e3 ff e0 07 00 0f 84 8d 00 00 00 fb 66 0f 1f 44 00 00 d8 fd ff ff 48 89 c1 48 c7 c2 60 fb cb 87 be 40 00 00 00 48 c7 RSP: 0018:ffffc9000015f7d8 EFLAGS: 00000282 RAX: 1ffffffff126e830 RBX: dffffc0000000000 RCX: 1ffffffff17fda62 RDX: 0000000000000000 RSI: ffffffff87cb4340 RDI: ffffffff88132660 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffffff8bfecba7 R10: fffffbfff17fd974 R11: 76203a2945474e41 R12: ffffffff89cea328 R13: 0000000000000000 R14: ffffffff89cea2f0 R15: 0000000000000200 FS: 0000000000000000(0000) GS:ffff8881f6500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005628f92e48d0 CR3: 000000000928e000 CR4: 0000000000350ee0 Call Trace: vprintk_emit+0x1d1/0x4c0 kernel/printk/printk.c:2174 printk+0xad/0xde kernel/printk/printk.c:2216 addrconf_notify.cold+0x50/0x61 net/ipv6/addrconf.c:3571 notifier_call_chain+0x94/0x170 kernel/notifier.c:83 netdev_state_change net/core/dev.c:1512 [inline] netdev_state_change+0xd7/0x100 net/core/dev.c:1505 linkwatch_do_dev+0xeb/0x120 net/core/link_watch.c:167 __linkwatch_run_queue+0x1ac/0x560 net/core/link_watch.c:212 linkwatch_event+0x37/0x50 net/core/link_watch.c:251 process_one_work+0x84c/0x13b0 kernel/workqueue.c:2275 worker_thread+0x598/0xf80 kernel/workqueue.c:2421 kthread+0x36f/0x450 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294