syzbot

INFO: task syz.0.17:4424 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17        state:D stack:29008 pid: 4424 ppid:  4314 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 rwsem_down_write_slowpath+0xc46/0x11f0 kernel/locking/rwsem.c:1165
 inode_lock_nested include/linux/fs.h:822 [inline]
 filename_create+0x1f2/0x450 fs/namei.c:3835
 do_mkdirat+0x9d/0x5a0 fs/namei.c:4080
 __do_sys_mkdirat fs/namei.c:4105 [inline]
 __se_sys_mkdirat fs/namei.c:4103 [inline]
 __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4103
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f60595b6ba9
RSP: 002b:00007f6058c05038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f60597fe090 RCX: 00007f60595b6ba9
RDX: 0000000000000000 RSI: 0000200000002040 RDI: ffffffffffffff9c
RBP: 00007f6059639e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f60597fe128 R14: 00007f60597fe090 R15: 00007ffebb2f8208
 </TASK>
INFO: task syz.3.20:4427 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.20        state:D stack:29088 pid: 4427 ppid:  4321 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 rwsem_down_write_slowpath+0xc46/0x11f0 kernel/locking/rwsem.c:1165
 inode_lock_nested include/linux/fs.h:822 [inline]
 filename_create+0x1f2/0x450 fs/namei.c:3835
 do_mkdirat+0x9d/0x5a0 fs/namei.c:4080
 __do_sys_mkdirat fs/namei.c:4105 [inline]
 __se_sys_mkdirat fs/namei.c:4103 [inline]
 __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4103
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fa6a3233ba9
RSP: 002b:00007fa6a2882038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007fa6a347b090 RCX: 00007fa6a3233ba9
RDX: 0000000000000000 RSI: 0000200000002040 RDI: ffffffffffffff9c
RBP: 00007fa6a32b6e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa6a347b128 R14: 00007fa6a347b090 R15: 00007ffd2c652588
 </TASK>
INFO: task syz.4.21:4436 blocked for more than 146 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.21        state:D stack:29088 pid: 4436 ppid:  4323 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 rwsem_down_write_slowpath+0xc46/0x11f0 kernel/locking/rwsem.c:1165
 inode_lock_nested include/linux/fs.h:822 [inline]
 filename_create+0x1f2/0x450 fs/namei.c:3835
 do_mkdirat+0x9d/0x5a0 fs/namei.c:4080
 __do_sys_mkdirat fs/namei.c:4105 [inline]
 __se_sys_mkdirat fs/namei.c:4103 [inline]
 __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4103
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc7c6cb6ba9
RSP: 002b:00007fc7c6305038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007fc7c6efe090 RCX: 00007fc7c6cb6ba9
RDX: 0000000000000000 RSI: 0000200000002040 RDI: ffffffffffffff9c
RBP: 00007fc7c6d39e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc7c6efe128 R14: 00007fc7c6efe090 R15: 00007ffd58d68cc8
 </TASK>
INFO: task syz.2.19:4435 blocked for more than 148 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.19        state:D stack:29088 pid: 4435 ppid:  4326 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 rwsem_down_write_slowpath+0xc46/0x11f0 kernel/locking/rwsem.c:1165
 inode_lock_nested include/linux/fs.h:822 [inline]
 filename_create+0x1f2/0x450 fs/namei.c:3835
 do_mkdirat+0x9d/0x5a0 fs/namei.c:4080
 __do_sys_mkdirat fs/namei.c:4105 [inline]
 __se_sys_mkdirat fs/namei.c:4103 [inline]
 __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4103
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f03c4ee8ba9
RSP: 002b:00007f03c4537038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f03c5130090 RCX: 00007f03c4ee8ba9
RDX: 0000000000000000 RSI: 0000200000002040 RDI: ffffffffffffff9c
RBP: 00007f03c4f6be19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f03c5130128 R14: 00007f03c5130090 R15: 00007ffc8d0d1718
 </TASK>
INFO: task syz.1.18:4437 blocked for more than 150 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.18        state:D stack:29088 pid: 4437 ppid:  4316 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 rwsem_down_write_slowpath+0xc46/0x11f0 kernel/locking/rwsem.c:1165
 inode_lock_nested include/linux/fs.h:822 [inline]
 filename_create+0x1f2/0x450 fs/namei.c:3835
 do_mkdirat+0x9d/0x5a0 fs/namei.c:4080
 __do_sys_mkdirat fs/namei.c:4105 [inline]
 __se_sys_mkdirat fs/namei.c:4103 [inline]
 __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4103
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fd8f209eba9
RSP: 002b:00007fd8f16ed038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007fd8f22e6090 RCX: 00007fd8f209eba9
RDX: 0000000000000000 RSI: 0000200000002040 RDI: ffffffffffffff9c
RBP: 00007fd8f2121e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd8f22e6128 R14: 00007fd8f22e6090 R15: 00007ffd5aa79348
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c11c660 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
1 lock held by kswapd0/254:
1 lock held by udevd/3559:
2 locks held by getty/3949:
 #0: ffff88814cfa1098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc900025e62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
2 locks held by kworker/u4:6/4338:
2 locks held by syz.0.17/4423:
1 lock held by syz.0.17/4424:
 #0: ffff8880599fc188 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:822 [inline]
 #0: ffff8880599fc188 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: filename_create+0x1f2/0x450 fs/namei.c:3835
1 lock held by syz.3.20/4426:
1 lock held by syz.3.20/4427:
 #0: ffff8880599fc6d0 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:822 [inline]
 #0: ffff8880599fc6d0 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: filename_create+0x1f2/0x450 fs/namei.c:3835
1 lock held by syz.4.21/4431:
1 lock held by syz.4.21/4436:
 #0: ffff8880599fd160 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:822 [inline]
 #0: ffff8880599fd160 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: filename_create+0x1f2/0x450 fs/namei.c:3835
1 lock held by syz.2.19/4432:
1 lock held by syz.2.19/4435:
 #0: ffff8880599fcc18 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:822 [inline]
 #0: ffff8880599fcc18 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: filename_create+0x1f2/0x450 fs/namei.c:3835
2 locks held by syz.1.18/4434:
1 lock held by syz.1.18/4437:
 #0: ffff8880599fd6a8 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:822 [inline]
 #0: ffff8880599fd6a8 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: filename_create+0x1f2/0x450 fs/namei.c:3835
2 locks held by syz.5.22/4533:
1 lock held by syz.5.22/4535:
 #0: ffff8880599fdbf0 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:822 [inline]
 #0: ffff8880599fdbf0 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: filename_create+0x1f2/0x450 fs/namei.c:3835
2 locks held by syz.9.26/4574:
1 lock held by syz.9.26/4575:
 #0: ffff8880599fe138 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:822 [inline]
 #0: ffff8880599fe138 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: filename_create+0x1f2/0x450 fs/namei.c:3835