Hello, When using Healer to fuzz the latest Linux kernel, the following crash was triggered. HEAD commit: 4357f03d6611 Merge tag 'pm-5.15-rc2 git tree: upstream console output: https://drive.google.com/file/d/1AJpdt-ENezAYZ0xo3787EvsK09-Vz404/view?usp=sharing kernel config: https://drive.google.com/file/d/1HKZtF_s3l6PL3OoQbNq_ei9CdBus-Tz0/view?usp=sharing If you fix this issue, please add the following tag to the commit: Reported-by: Hao Sun <sunhao.th@xxxxxxxxx> BUG: sleeping function called from invalid context at kernel/rcu/tree_exp.h:854 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 21, name: ksoftirqd/1 2 locks held by ksoftirqd/1/21: #0: ffffffff85a1d4a0 (rcu_callback){....}-{0:0}, at: rcu_do_batch kernel/rcu/tree.c:2500 [inline] #0: ffffffff85a1d4a0 (rcu_callback){....}-{0:0}, at: rcu_core+0x283/0x9f0 kernel/rcu/tree.c:2743 #1: ffffffff85a1fd28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #1: ffffffff85a1fd28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x32d/0x460 kernel/rcu/tree_exp.h:837 Preemption disabled at: [<ffffffff8460005c>] softirq_handle_begin kernel/softirq.c:396 [inline] [<ffffffff8460005c>] __do_softirq+0x5c/0x561 kernel/softirq.c:534 CPU: 1 PID: 21 Comm: ksoftirqd/1 Not tainted 5.15.0-rc1+ #19 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x8d/0xcf lib/dump_stack.c:106 ___might_sleep+0x1f0/0x250 kernel/sched/core.c:9538 synchronize_rcu_expedited+0x2db/0x460 kernel/rcu/tree_exp.h:853 bdi_remove_from_list mm/backing-dev.c:938 [inline] bdi_unregister+0x97/0x270 mm/backing-dev.c:946 release_bdi+0x4a/0x70 mm/backing-dev.c:968 kref_put include/linux/kref.h:65 [inline] bdi_put+0x47/0x70 mm/backing-dev.c:976 bdev_free_inode+0x59/0xc0 block/bdev.c:408 i_callback+0x24/0x50 fs/inode.c:224 rcu_do_batch kernel/rcu/tree.c:2508 [inline] rcu_core+0x2d6/0x9f0 kernel/rcu/tree.c:2743 __do_softirq+0xe9/0x561 kernel/softirq.c:558 run_ksoftirqd+0x2d/0x60 kernel/softirq.c:920 smpboot_thread_fn+0x225/0x320 kernel/smpboot.c:164 kthread+0x178/0x1b0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 BUG: scheduling while atomic: ksoftirqd/1/21/0x00000101 2 locks held by ksoftirqd/1/21: #0: ffffffff85a1d4a0 (rcu_callback){....}-{0:0}, at: rcu_do_batch kernel/rcu/tree.c:2500 [inline] #0: ffffffff85a1d4a0 (rcu_callback){....}-{0:0}, at: rcu_core+0x283/0x9f0 kernel/rcu/tree.c:2743 #1: ffffffff85a1fd28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #1: ffffffff85a1fd28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x32d/0x460 kernel/rcu/tree_exp.h:837 Modules linked in: Preemption disabled at: [<ffffffff8460005c>] softirq_handle_begin kernel/softirq.c:396 [inline] [<ffffffff8460005c>] __do_softirq+0x5c/0x561 kernel/softirq.c:534
