INFO: task syz-executor386:8105 blocked for more than 140 seconds. Not tainted 4.19.211-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor386 D27400 8105 8103 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 fuse_wait_on_page_writeback fs/fuse/file.c:383 [inline] fuse_wait_on_page_writeback.isra.0+0x11b/0x170 fs/fuse/file.c:379 fuse_launder_page fs/fuse/file.c:2033 [inline] fuse_launder_page+0xb6/0xe0 fs/fuse/file.c:2026 do_launder_page mm/truncate.c:655 [inline] invalidate_inode_pages2_range+0x795/0x1110 mm/truncate.c:725 fuse_finish_open+0x2e2/0x590 fs/fuse/file.c:182 fuse_open_common+0x254/0x2c0 fs/fuse/file.c:222 do_dentry_open+0x4aa/0x1160 fs/open.c:796 do_last fs/namei.c:3421 [inline] path_openat+0x793/0x2df0 fs/namei.c:3537 do_filp_open+0x18c/0x3f0 fs/namei.c:3567 do_sys_open+0x3b3/0x520 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f80d2f0d509 Code: Bad RIP value. RSP: 002b:00007f80d2ebe2f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 00007f80d2f9e4c0 RCX: 00007f80d2f0d509 RDX: 00007f80d2f0d509 RSI: 0000000000000000 RDI: 0000000020000400 RBP: 00007f80d2f6b164 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0030656c69662f2e R13: 00007f80d2f67158 R14: 00007f80d2f69160 R15: 00007f80d2f9e4c8 Showing all locks held in the system: 1 lock held by khungtaskd/1570: #0: 00000000f6a4dfa2 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 2 locks held by syz-executor386/8105: #0: 00000000d0c65fea (sb_writers#11){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline] #0: 00000000d0c65fea (sb_writers#11){.+.+}, at: mnt_want_write+0x3a/0xb0 fs/namespace.c:360 #1: 000000000b1f1adb (&sb->s_type->i_mutex_key#17){+.+.}, at: inode_lock include/linux/fs.h:748 [inline] #1: 000000000b1f1adb (&sb->s_type->i_mutex_key#17){+.+.}, at: fuse_open_common+0x1bc/0x2c0 fs/fuse/file.c:215 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1570 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x991/0xe60 kernel/hung_task.c:287 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4691 Comm: systemd-journal Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:___bpf_prog_run+0x1262/0x4e80 kernel/bpf/core.c:1281 Code: f8 83 e0 07 83 c0 03 38 c8 7c 08 84 c9 0f 85 0e 2c 00 00 4d 63 7e 04 48 89 d7 48 89 14 24 4c 89 fe e8 82 3d f6 ff 48 8b 14 24 <4c> 39 fa 0f 82 0d 24 00 00 e8 60 3c f6 ff 49 8d 7e 02 48 89 f8 48 RSP: 0018:ffff8880a0e3fa30 EFLAGS: 00000293 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffffffff816c48fe RDX: 0000000000000027 RSI: ffff8880a0e34540 RDI: 0000000000000006 RBP: ffff8880a0e3fb00 R08: 0000000000000000 R09: 0000000000000027 R10: 0000000000000006 R11: 0000000000000000 R12: ffffffff886fb460 R13: ffffed10141c7f62 R14: ffffc90001a95070 R15: 0000000040000000 FS: 00007feb820748c0(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007feb7f445000 CR3: 00000000a11d5000 CR4: 00000000003406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ---------------- Code disassembly (best guess): 0: f8 clc 1: 83 e0 07 and $0x7,%eax 4: 83 c0 03 add $0x3,%eax 7: 38 c8 cmp %cl,%al 9: 7c 08 jl 0x13 b: 84 c9 test %cl,%cl d: 0f 85 0e 2c 00 00 jne 0x2c21 13: 4d 63 7e 04 movslq 0x4(%r14),%r15 17: 48 89 d7 mov %rdx,%rdi 1a: 48 89 14 24 mov %rdx,(%rsp) 1e: 4c 89 fe mov %r15,%rsi 21: e8 82 3d f6 ff callq 0xfff63da8 26: 48 8b 14 24 mov (%rsp),%rdx * 2a: 4c 39 fa cmp %r15,%rdx <-- trapping instruction 2d: 0f 82 0d 24 00 00 jb 0x2440 33: e8 60 3c f6 ff callq 0xfff63c98 38: 49 8d 7e 02 lea 0x2(%r14),%rdi 3c: 48 89 f8 mov %rdi,%rax 3f: 48 rex.W