INFO: task syz-executor.2:10444 blocked for more than 143 seconds. Not tainted 6.0.0-syzkaller-09589-g55be6084c8e0 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:25520 pid:10444 ppid:3432 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5178 [inline] __schedule+0xadf/0x5270 kernel/sched/core.c:6490 schedule+0xda/0x1b0 kernel/sched/core.c:6566 wb_wait_for_completion+0x17e/0x240 fs/fs-writeback.c:191 __writeback_inodes_sb_nr+0x1d7/0x280 fs/fs-writeback.c:2620 try_to_writeback_inodes_sb+0x94/0xc0 fs/fs-writeback.c:2668 ext4_nonda_switch+0x1aa/0x1f0 fs/ext4/inode.c:2950 ext4_da_write_begin+0x16d/0xae0 fs/ext4/inode.c:2977 generic_perform_write+0x246/0x560 mm/filemap.c:3745 ext4_buffered_write_iter+0x15b/0x460 fs/ext4/file.c:285 ext4_file_write_iter+0x8b8/0x16e0 fs/ext4/file.c:700 __kernel_write_iter+0x25e/0x730 fs/read_write.c:517 dump_emit_page fs/coredump.c:857 [inline] dump_user_range+0x230/0x700 fs/coredump.c:908 elf_core_dump+0x26de/0x3510 fs/binfmt_elf.c:2311 do_coredump+0x2732/0x3c40 fs/coredump.c:755 get_signal+0x1be1/0x2430 kernel/signal.c:2844 arch_do_signal_or_restart+0x82/0x2300 arch/x86/kernel/signal.c:869 exit_to_user_mode_loop kernel/entry/common.c:166 [inline] exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:201 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:307 exc_page_fault+0xbc/0x170 arch/x86/mm/fault.c:1557 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570 RIP: 0033:0x7f862aa27d77 RSP: 002b:00007f86299df260 EFLAGS: 00010206 RAX: 0000000000000000 RBX: 00007f862abac050 RCX: 00007f862aa8b5a9 RDX: 00007f86299df280 RSI: 00007f86299df3b0 RDI: 000000000000000b RBP: 000000000000000b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007ffcee8bb08f R14: 00007f86299fe300 R15: 0000000000022000 INFO: lockdep is turned off. NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.0.0-syzkaller-09589-g55be6084c8e0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x46/0x14f lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x206/0x250 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xbf9/0xf30 kernel/hung_task.c:377 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3474 Comm: kworker/1:1 Not tainted 6.0.0-syzkaller-09589-g55be6084c8e0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 Workqueue: events nsim_dev_trap_report_work RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:166 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:200 Code: 48 89 ef 5d e9 f1 c4 4c 00 5d be 03 00 00 00 e9 d6 43 84 02 66 0f 1f 44 00 00 48 8b be a8 01 00 00 e8 b4 ff ff ff 31 c0 c3 90 <65> 8b 05 f9 24 87 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b RSP: 0018:ffffc9000351f8c0 EFLAGS: 00000283 RAX: 0000000000000000 RBX: ffffffff91227060 RCX: ffffffff81c8fc96 RDX: ffff88807a5b3b00 RSI: 0000000000000000 RDI: 0000000000000006 RBP: ffff88823bcf26da R08: 0000000000000006 R09: ffff88823bcf26da R10: ffff88823bcf2f00 R11: 0000000000000001 R12: dffffc0000000000 R13: ffff88823bcf2f00 R14: ffff88823bcf2f00 R15: ffff88823bcf2f00 FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f616b8a1990 CR3: 000000000bc8e000 CR4: 0000000000350ee0 Call Trace: for_each_canary mm/kfence/core.c:344 [inline] kfence_guarded_alloc mm/kfence/core.c:438 [inline] __kfence_alloc+0xed6/0x1580 mm/kfence/core.c:1042 kfence_alloc include/linux/kfence.h:128 [inline] slab_alloc_node mm/slub.c:3166 [inline] kmem_cache_alloc_node+0x227/0x3f0 mm/slub.c:3298 __alloc_skb+0x210/0x2f0 net/core/skbuff.c:497 alloc_skb include/linux/skbuff.h:1265 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:742 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:799 [inline] nsim_dev_trap_report_work+0x2ad/0xc50 drivers/net/netdevsim/dev.c:844 process_one_work+0x991/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306