INFO: task syz-executor.5:5373 blocked for more than 143 seconds. Not tainted 5.15.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:26464 pid: 5373 ppid: 10859 flags:0x00024004 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6287 schedule+0xd3/0x270 kernel/sched/core.c:6366 schedule_timeout+0x1db/0x2a0 kernel/time/timer.c:1857 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x176/0x280 kernel/sched/completion.c:138 io_wq_exit_workers fs/io-wq.c:1181 [inline] io_wq_put_and_exit+0x4b2/0xd20 fs/io-wq.c:1216 io_uring_clean_tctx fs/io_uring.c:9614 [inline] io_uring_cancel_generic+0x5fe/0x740 fs/io_uring.c:9694 io_uring_files_cancel include/linux/io_uring.h:16 [inline] do_exit+0x265/0x2a30 kernel/exit.c:780 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x47f/0x2160 kernel/signal.c:2868 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:865 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665f9 RSP: 002b:00007f07ce5ef188 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: 00000000000002e7 RBX: 000000000056c038 RCX: 00000000004665f9 RDX: 000000000000011f RSI: 0000000000006b46 RDI: 0000000000000006 RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038 R13: 00007ffd4f989aaf R14: 00007f07ce5ef300 R15: 0000000000022000 INFO: task syz-executor.0:5441 blocked for more than 143 seconds. Not tainted 5.15.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:26536 pid: 5441 ppid: 6544 flags:0x00024004 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6287 schedule+0xd3/0x270 kernel/sched/core.c:6366 schedule_timeout+0x1db/0x2a0 kernel/time/timer.c:1857 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x176/0x280 kernel/sched/completion.c:138 io_wq_exit_workers fs/io-wq.c:1181 [inline] io_wq_put_and_exit+0x4b2/0xd20 fs/io-wq.c:1216 io_uring_clean_tctx fs/io_uring.c:9614 [inline] io_uring_cancel_generic+0x5fe/0x740 fs/io_uring.c:9694 io_uring_files_cancel include/linux/io_uring.h:16 [inline] do_exit+0x265/0x2a30 kernel/exit.c:780 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x47f/0x2160 kernel/signal.c:2868 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:865 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665f9 RSP: 002b:00007fe705736188 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: 0000000000000433 RBX: 000000000056c038 RCX: 00000000004665f9 RDX: 000000000000011f RSI: 0000000000006b46 RDI: 0000000000000006 RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038 R13: 00007ffcfe67ea5f R14: 00007fe705736300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8b97fe20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446 1 lock held by in:imklog/6257: #0: ffff88807480d9f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 2 locks held by rs:main Q:Reg/6262: #0: ffff88801a11c5f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 #1: ffff888147f38460 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x12d/0x250 fs/read_write.c:647 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xc1d/0xf50 kernel/hung_task.c:295 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 6262 Comm: rs:main Q:Reg Not tainted 5.15.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:write_comp_data kernel/kcov.c:218 [inline] RIP: 0010:__sanitizer_cov_trace_cmp8+0x3/0x70 kernel/kcov.c:264 Code: 1f 48 83 c2 01 4c 89 44 38 e8 48 c7 44 38 e0 07 00 00 00 48 89 4c 38 f0 4e 89 54 c8 20 48 89 10 c3 66 0f 1f 44 00 00 49 89 f8 03 00 00 00 4c 8b 14 24 48 89 f1 65 48 8b 34 25 40 f0 01 00 e8 RSP: 0018:ffffc9000c22f410 EFLAGS: 00000082 RAX: 00000000ffffffa8 RBX: ffffffff902a73f8 RCX: 0000000000000002 RDX: 0000000000000000 RSI: ffff88823bd95000 RDI: ffff88823bd941d3 RBP: ffff88823bd95000 R08: ffff88823bd941d3 R09: ffffffff8eef300f R10: ffffffff81bd8bb0 R11: 0000000000000001 R12: ffff888140ff2b40 R13: 0000000000000040 R14: ffff88823bd941d3 R15: dffffc0000000000 FS: 00007f3b6316e700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fea85119018 CR3: 000000007434e000 CR4: 0000000000350ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: for_each_canary mm/kfence/core.c:254 [inline] kfence_guarded_alloc mm/kfence/core.c:321 [inline] __kfence_alloc+0x710/0xca0 mm/kfence/core.c:779 kfence_alloc include/linux/kfence.h:124 [inline] slab_alloc_node mm/slub.c:3124 [inline] slab_alloc mm/slub.c:3214 [inline] kmem_cache_alloc+0x1c4/0x390 mm/slub.c:3219 kmem_cache_zalloc include/linux/slab.h:711 [inline] ext4_init_io_end+0x23/0x170 fs/ext4/page-io.c:276 ext4_writepages+0x8fd/0x3ba0 fs/ext4/inode.c:2755 do_writepages+0x1ab/0x7b0 mm/page-writeback.c:2364 filemap_fdatawrite_wbc mm/filemap.c:400 [inline] filemap_fdatawrite_wbc+0x1d6/0x2f0 mm/filemap.c:390 __filemap_fdatawrite_range mm/filemap.c:433 [inline] file_write_and_wait_range+0x163/0x1e0 mm/filemap.c:810 ext4_sync_file+0x21f/0xfd0 fs/ext4/fsync.c:151 vfs_fsync_range+0x13a/0x220 fs/sync.c:200 generic_write_sync include/linux/fs.h:2955 [inline] ext4_buffered_write_iter+0x36a/0x500 fs/ext4/file.c:277 ext4_file_write_iter+0x423/0x14e0 fs/ext4/file.c:680 call_write_iter include/linux/fs.h:2163 [inline] new_sync_write+0x40b/0x640 fs/read_write.c:507 vfs_write+0x7cf/0xae0 fs/read_write.c:594 ksys_write+0x12d/0x250 fs/read_write.c:647 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f3b65bb21cd Code: c2 20 00 00 75 10 b8 01 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ae fc ff ff 48 89 04 24 b8 01 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 f7 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007f3b6316d590 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f3b580272a0 RCX: 00007f3b65bb21cd RDX: 0000000000000088 RSI: 00007f3b580272a0 RDI: 000000000000000a RBP: 0000000000000000 R08: 0000000000000000 R09: 3a7461202c7d333a R10: 0000000000000000 R11: 0000000000000293 R12: 00007f3b58027020 R13: 00007f3b6316d5b0 R14: 000055a5032337c0 R15: 0000000000000088 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 48 83 c2 01 add $0x1,%rdx 4: 4c 89 44 38 e8 mov %r8,-0x18(%rax,%rdi,1) 9: 48 c7 44 38 e0 07 00 movq $0x7,-0x20(%rax,%rdi,1) 10: 00 00 12: 48 89 4c 38 f0 mov %rcx,-0x10(%rax,%rdi,1) 17: 4e 89 54 c8 20 mov %r10,0x20(%rax,%r9,8) 1c: 48 89 10 mov %rdx,(%rax) 1f: c3 retq 20: 66 0f 1f 44 00 00 nopw 0x0(%rax,%rax,1) 26: 49 89 f8 mov %rdi,%r8 * 29: bf 03 00 00 00 mov $0x3,%edi <-- trapping instruction 2e: 4c 8b 14 24 mov (%rsp),%r10 32: 48 89 f1 mov %rsi,%rcx 35: 65 48 8b 34 25 40 f0 mov %gs:0x1f040,%rsi 3c: 01 00 3e: e8 .byte 0xe8