INFO: task syz-executor0:13722 blocked for more than 140 seconds.
      Not tainted 4.19.0-rc7+ #53
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor0   D24240 13722   5903 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2825 [inline]
 __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473
 schedule+0xfe/0x460 kernel/sched/core.c:3517
 __rwsem_down_write_failed_common+0xbb9/0x1670 kernel/locking/rwsem-xadd.c:566
 rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:595
 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117
 __down_write arch/x86/include/asm/rwsem.h:142 [inline]
 down_write+0xa5/0x130 kernel/locking/rwsem.c:72
 inode_lock include/linux/fs.h:738 [inline]
 chown_common+0x3a9/0x730 fs/open.c:629
 do_fchownat+0x16e/0x250 fs/open.c:662
 __do_sys_lchown fs/open.c:687 [inline]
 __se_sys_lchown fs/open.c:685 [inline]
 __x64_sys_lchown+0x7e/0xc0 fs/open.c:685
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457579
Code: Bad RIP value.
RSP: 002b:00007f47bd6dac78 EFLAGS: 00000246 ORIG_RAX: 000000000000005e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457579
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000080
RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f47bd6db6d4
R13: 00000000004c26cf R14: 00000000004d37f8 R15: 00000000ffffffff
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 PID: 986 Comm: khungtaskd Not tainted 4.19.0-rc7+ #53
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+0x1c4/0x2b4 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold.3+0x63/0xa2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1b3/0x1ed 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:144 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline]
 watchdog+0xb3e/0x1050 kernel/hung_task.c:265
 kthread+0x35a/0x420 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413
Sending NMI from CPU 1 to CPUs 0:
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.745 msecs
NMI backtrace for cpu 0
CPU: 0 PID: 5903 Comm: syz-executor0 Not tainted 4.19.0-rc7+ #53
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:check_kcov_mode kernel/kcov.c:67 [inline]
RIP: 0010:write_comp_data+0x1b/0x70 kernel/kcov.c:122
Code: ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 65 4c 8b 04 25 40 ee 01 00 65 8b 05 9f 18 83 7e a9 00 01 1f 00 48 89 e5 75 51 <41> 8b 80 d0 12 00 00 83 f8 03 75 45 49 8b 80 d8 12 00 00 45 8b 80
RSP: 0018:ffff8801bef9e800 EFLAGS: 00000046
RAX: 0000000080000000 RBX: 0000000000000000 RCX: ffffffff838d491a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: ffff8801bef9e800 R08: ffff8801ce720440 R09: fffff94000bd987e
R10: fffff94000bd987e R11: ffffea0005ecc3f7 R12: 0000000000000000
R13: ffffffff88408fc0 R14: ffffffff88158720 R15: dffffc0000000000
FS:  0000000002692940(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffff600400 CR3: 00000001d37d1000 CR4: 00000000001406f0
DR0: 0000000000004000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __sanitizer_cov_trace_const_cmp4+0x16/0x20 kernel/kcov.c:188
 check_preemption_disabled+0x3a/0x200 lib/smp_processor_id.c:15
 __this_cpu_preempt_check+0x1c/0x1f lib/smp_processor_id.c:62
 lookup_bh_lru fs/buffer.c:1261 [inline]
 __find_get_block+0x183/0xf20 fs/buffer.c:1290
 __getblk_slow fs/buffer.c:1039 [inline]
 __getblk_gfp+0x2b3/0xd50 fs/buffer.c:1320
 __bread_gfp+0x2d/0x300 fs/buffer.c:1354
 sb_bread include/linux/buffer_head.h:307 [inline]
 fat__get_entry+0x5a6/0xa40 fs/fat/dir.c:101
 fat_get_entry fs/fat/dir.c:129 [inline]
 fat_search_long+0x33b/0x1570 fs/fat/dir.c:477
 vfat_find+0x16d/0x1a0 fs/fat/namei_vfat.c:697
 vfat_lookup+0x107/0x640 fs/fat/namei_vfat.c:711
 __lookup_slow+0x2b5/0x540 fs/namei.c:1671
 lookup_slow+0x57/0x80 fs/namei.c:1688
 walk_component+0x92b/0x25c0 fs/namei.c:1810
 link_path_walk.part.40+0xa61/0x1530 fs/namei.c:2141
 link_path_walk fs/namei.c:2072 [inline]
 path_openat+0x270/0x5160 fs/namei.c:3533
 do_filp_open+0x255/0x380 fs/namei.c:3564
 do_sys_open+0x568/0x700 fs/open.c:1063
 __do_sys_open fs/open.c:1081 [inline]
 __se_sys_open fs/open.c:1076 [inline]
 __x64_sys_open+0x7e/0xc0 fs/open.c:1076
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4555a0
Code: 31 c0 e9 45 ff ff ff 0f 1f 00 80 3f 00 0f 84 f7 00 00 00 55 53 b9 02 00 00 00 be 00 08 09 00 89 c8 48 81 ec 98 00 00 00 0f 05 <48> 3d 00 f0 ff ff 48 89 c3 0f 87 e9 00 00 00 85 db 0f 88 2f 01 00
RSP: 002b:00007fff20d28140 EFLAGS: 00000202 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004555a0
RDX: 0000000000000000 RSI: 0000000000090800 RDI: 00000000004bc2ce
RBP: 000000000000044f R08: 0000000000000001 R09: 0000000002692940
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000011
R13: 000000000004fc8a R14: 00000000000000fb R15: 0000000000000000