VMExit: intr_info=00000000 errcode=00000000 ilen=00000002 reason=80000021 qualification=0000000000000000 IDTVectoring: info=00000000 errcode=00000000 TSC Offset = 0xffffff118296ae56 EPT pointer = 0x00000001c0fac01e INFO: task syz-executor0:20334 blocked for more than 140 seconds. Not tainted 4.20.0-rc2+ #333 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D22776 20334 6010 0x00000004 Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472 schedule+0xfe/0x460 kernel/sched/core.c:3516 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3574 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0xaff/0x16f0 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 lock_fat fs/fat/fatent.c:279 [inline] fat_count_free_clusters+0x122/0xe30 fs/fat/fatent.c:658 fat_statfs+0x3b4/0x4c0 fs/fat/inode.c:822 statfs_by_dentry+0x136/0x210 fs/statfs.c:64 vfs_statfs+0x47/0x2e0 fs/statfs.c:74 fd_statfs+0x48/0x90 fs/statfs.c:104 __do_sys_fstatfs+0x7f/0xf0 fs/statfs.c:200 __se_sys_fstatfs fs/statfs.c:197 [inline] __x64_sys_fstatfs+0x54/0x80 fs/statfs.c:197 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457569 Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f1bbc23cc78 EFLAGS: 00000246 ORIG_RAX: 000000000000008a RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000457569 RDX: 0000000000000000 RSI: 00000000200004c0 RDI: 000000000000000b RBP: 000000000072c0e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f1bbc23d6d4 R13: 00000000004bde43 R14: 00000000004cd018 R15: 00000000ffffffff Showing all locks held in the system: 4 locks held by kworker/u4:0/7: 1 lock held by khungtaskd/1008: #0: 000000007b8bda24 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4379 1 lock held by rsyslogd/5881: #0: 0000000047e3413a (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/5971: #0: 00000000396bfe40 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000ea44d7dd (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5972: #0: 0000000069a67833 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000093966da8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5973: #0: 00000000cd3882ca (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000099337b68 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5974: #0: 000000008998704c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000049f1bda2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5975: #0: 00000000e1d7c71b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000c3641ab7 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5976: #0: 00000000a1b0ff3b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000df77e02f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5977: #0: 000000008a50ebd8 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000006caab482 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 1 lock held by syz-executor1/13534: #0: 000000002e70d2b8 (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds+0x53/0x120 fs/exec.c:1404 2 locks held by syz-executor0/20283: 1 lock held by syz-executor0/20334: #0: 000000002370b28b (&sbi->fat_lock){+.+.}, at: lock_fat fs/fat/fatent.c:279 [inline] #0: 000000002370b28b (&sbi->fat_lock){+.+.}, at: fat_count_free_clusters+0x122/0xe30 fs/fat/fatent.c:658 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1008 Comm: khungtaskd Not tainted 4.20.0-rc2+ #333 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+0x244/0x39d lib/dump_stack.c:113 nmi_cpu_backtrace.cold.2+0x5c/0xa1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1e8/0x22a lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xb51/0x1060 kernel/hung_task.c:289 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.041 msecs NMI backtrace for cpu 1 CPU: 1 PID: 7 Comm: kworker/u4:0 Not tainted 4.20.0-rc2+ #333 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-7:0) RIP: 0010:arch_atomic_try_cmpxchg arch/x86/include/asm/atomic.h:200 [inline] RIP: 0010:atomic_try_cmpxchg include/asm-generic/atomic-instrumented.h:73 [inline] RIP: 0010:atomic_fetch_add_unless include/linux/atomic.h:580 [inline] RIP: 0010:atomic_add_unless include/linux/atomic.h:597 [inline] RIP: 0010:page_ref_add_unless include/linux/page_ref.h:157 [inline] RIP: 0010:get_page_unless_zero include/linux/mm.h:531 [inline] RIP: 0010:page_cache_get_speculative include/linux/pagemap.h:186 [inline] RIP: 0010:find_get_entry+0x5eb/0x1120 mm/filemap.c:1426 Code: 2b 85 25 00 41 0f b6 06 84 c0 74 08 3c 03 0f 8e 60 09 00 00 41 8b 9c 24 e0 fc ff ff 48 8b 95 80 fc ff ff 89 d8 f0 44 0f b1 2a <41> 0f 94 c5 31 ff 89 c3 44 89 ee e8 65 49 e2 ff 45 84 ed 0f 84 b8 RSP: 0018:ffff8881d9ae5cc0 EFLAGS: 00000246 RAX: 0000000000000002 RBX: 0000000000000002 RCX: ffffffff819d3f15 RDX: ffffea000710f2b4 RSI: 0000000000000004 RDI: ffff8881d9ae5d30 RBP: ffff8881d9ae6078 R08: ffffed103b35cba7 R09: ffffed103b35cba6 R10: ffffed103b35cba6 R11: 0000000000000003 R12: ffff8881d9ae6050 R13: 0000000000000003 R14: ffffed103b35cba6 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8881daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001ca400000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: pagecache_get_page+0x12f/0xf00 mm/filemap.c:1518 find_or_create_page include/linux/pagemap.h:322 [inline] grow_dev_page fs/buffer.c:947 [inline] grow_buffers fs/buffer.c:1016 [inline] __getblk_slow fs/buffer.c:1043 [inline] __getblk_gfp+0x3aa/0xd50 fs/buffer.c:1320 __bread_gfp+0x2d/0x310 fs/buffer.c:1354 sb_bread include/linux/buffer_head.h:307 [inline] __fat_write_inode+0x347/0xb60 fs/fat/inode.c:859 fat_write_inode+0x97/0x180 fs/fat/inode.c:908 write_inode fs/fs-writeback.c:1176 [inline] __writeback_single_inode+0xf56/0x1660 fs/fs-writeback.c:1375 writeback_sb_inodes+0x71f/0x1210 fs/fs-writeback.c:1580 __writeback_inodes_wb+0x1b9/0x340 fs/fs-writeback.c:1649 wb_writeback+0xa73/0xfc0 fs/fs-writeback.c:1758 wb_check_start_all fs/fs-writeback.c:1882 [inline] wb_do_writeback fs/fs-writeback.c:1908 [inline] wb_workfn+0xee9/0x1790 fs/fs-writeback.c:1942 process_one_work+0xc90/0x1c40 kernel/workqueue.c:2153 worker_thread+0x17f/0x1390 kernel/workqueue.c:2296 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352