============================= WARNING: suspicious RCU usage 5.12.0-rc6-syzkaller #0 Not tainted ----------------------------- kernel/sched/core.c:8294 Illegal context switch in RCU-bh read-side critical section! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 4 locks held by kworker/1:8/9733: #0: ffff888021575538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888021575538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888021575538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888021575538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888021575538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888021575538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x871/0x1600 kernel/workqueue.c:2246 #1: ffffc90015e87da8 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1600 kernel/workqueue.c:2250 #2: ffffffff8d6716e8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4572 #3: ffffffff8bf74480 (rcu_read_lock_bh){....}-{1:2}, at: addrconf_verify_rtnl+0x2b/0x1150 net/ipv6/addrconf.c:4459 stack backtrace: CPU: 1 PID: 9733 Comm: kworker/1:8 Not tainted 5.12.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: ipv6_addrconf addrconf_verify_work Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 ___might_sleep+0x229/0x2c0 kernel/sched/core.c:8294 __mutex_lock_common kernel/locking/mutex.c:928 [inline] __mutex_lock+0xa9/0x1120 kernel/locking/mutex.c:1096 __ipv6_dev_mc_dec+0x5f/0x340 net/ipv6/mcast.c:968 addrconf_leave_solict net/ipv6/addrconf.c:2182 [inline] addrconf_leave_solict net/ipv6/addrconf.c:2174 [inline] __ipv6_ifa_notify+0x5b6/0xa90 net/ipv6/addrconf.c:6097 ipv6_ifa_notify net/ipv6/addrconf.c:6120 [inline] ipv6_del_addr+0x463/0xae0 net/ipv6/addrconf.c:1294 addrconf_verify_rtnl+0xd59/0x1150 net/ipv6/addrconf.c:4488 addrconf_verify_work+0xf/0x20 net/ipv6/addrconf.c:4573 process_one_work+0x98d/0x1600 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 BUG: sleeping function called from invalid context at kernel/locking/mutex.c:928 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 9733, name: kworker/1:8 4 locks held by kworker/1:8/9733: #0: ffff888021575538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888021575538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888021575538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888021575538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888021575538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888021575538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x871/0x1600 kernel/workqueue.c:2246 #1: ffffc90015e87da8 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1600 kernel/workqueue.c:2250 #2: ffffffff8d6716e8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4572 #3: ffffffff8bf74480 (rcu_read_lock_bh){....}-{1:2}, at: addrconf_verify_rtnl+0x2b/0x1150 net/ipv6/addrconf.c:4459 Preemption disabled at: [] local_bh_disable include/linux/bottom_half.h:19 [inline] [] rcu_read_lock_bh include/linux/rcupdate.h:727 [inline] [] addrconf_verify_rtnl+0x41/0x1150 net/ipv6/addrconf.c:4461 CPU: 1 PID: 9733 Comm: kworker/1:8 Not tainted 5.12.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: ipv6_addrconf addrconf_verify_work Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 ___might_sleep.cold+0x1f1/0x237 kernel/sched/core.c:8328 __mutex_lock_common kernel/locking/mutex.c:928 [inline] __mutex_lock+0xa9/0x1120 kernel/locking/mutex.c:1096 __ipv6_dev_mc_dec+0x5f/0x340 net/ipv6/mcast.c:968 addrconf_leave_solict net/ipv6/addrconf.c:2182 [inline] addrconf_leave_solict net/ipv6/addrconf.c:2174 [inline] __ipv6_ifa_notify+0x5b6/0xa90 net/ipv6/addrconf.c:6097 ipv6_ifa_notify net/ipv6/addrconf.c:6120 [inline] ipv6_del_addr+0x463/0xae0 net/ipv6/addrconf.c:1294 addrconf_verify_rtnl+0xd59/0x1150 net/ipv6/addrconf.c:4488 addrconf_verify_work+0xf/0x20 net/ipv6/addrconf.c:4573 process_one_work+0x98d/0x1600 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 ============================= [ BUG: Invalid wait context ] 5.12.0-rc6-syzkaller #0 Tainted: G W ----------------------------- kworker/1:8/9733 is trying to lock: ffff88805eb66530 (&idev->mc_lock){+.+.}-{3:3}, at: __ipv6_dev_mc_dec+0x5f/0x340 net/ipv6/mcast.c:968 other info that might help us debug this: context-{4:4} 4 locks held by kworker/1:8/9733: #0: ffff888021575538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888021575538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888021575538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888021575538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888021575538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888021575538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x871/0x1600 kernel/workqueue.c:2246 #1: ffffc90015e87da8 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1600 kernel/workqueue.c:2250 #2: ffffffff8d6716e8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4572 #3: ffffffff8bf74480 (rcu_read_lock_bh){....}-{1:2}, at: addrconf_verify_rtnl+0x2b/0x1150 net/ipv6/addrconf.c:4459 stack backtrace: CPU: 1 PID: 9733 Comm: kworker/1:8 Tainted: G W 5.12.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: ipv6_addrconf addrconf_verify_work Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 print_lock_invalid_wait_context kernel/locking/lockdep.c:4551 [inline] check_wait_context kernel/locking/lockdep.c:4612 [inline] __lock_acquire.cold+0x219/0x3b4 kernel/locking/lockdep.c:4850 lock_acquire kernel/locking/lockdep.c:5510 [inline] lock_acquire+0x1ab/0x740 kernel/locking/lockdep.c:5475 __mutex_lock_common kernel/locking/mutex.c:949 [inline] __mutex_lock+0x139/0x1120 kernel/locking/mutex.c:1096 __ipv6_dev_mc_dec+0x5f/0x340 net/ipv6/mcast.c:968 addrconf_leave_solict net/ipv6/addrconf.c:2182 [inline] addrconf_leave_solict net/ipv6/addrconf.c:2174 [inline] __ipv6_ifa_notify+0x5b6/0xa90 net/ipv6/addrconf.c:6097 ipv6_ifa_notify net/ipv6/addrconf.c:6120 [inline] ipv6_del_addr+0x463/0xae0 net/ipv6/addrconf.c:1294 addrconf_verify_rtnl+0xd59/0x1150 net/ipv6/addrconf.c:4488 addrconf_verify_work+0xf/0x20 net/ipv6/addrconf.c:4573 process_one_work+0x98d/0x1600 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294