Comment 11 for bug 1824981

The "NULL pointer dereference" bug create state D pocesses waiting in call_rwsem_down_write_failed.

[ +0.000341] genesplicer D 0 53349 52579 0x80000000
[ +0.000362] Call Trace:
[ +0.000346] __schedule+0x291/0x8a0
[ +0.000348] ? mempool_free+0x2f/0x90
[ +0.000347] schedule+0x2c/0x80
[ +0.000356] rwsem_down_write_failed+0x169/0x360
[ +0.000344] ? is_size_safe_to_change+0x3c/0xd0 [cifs]
[ +0.000339] call_rwsem_down_write_failed+0x17/0x30
[ +0.000336] ? call_rwsem_down_write_failed+0x17/0x30
[ +0.000332] down_write+0x2d/0x40
[ +0.000331] cifs_new_fileinfo+0xc3/0x3a0 [cifs]
[ +0.000332] cifs_open+0x3db/0x8d0 [cifs]
[ +0.000329] do_dentry_open+0x1c2/0x310
[ +0.000360] ? cifs_uncached_writev_complete+0x3f0/0x3f0 [cifs]
[ +0.000340] ? do_dentry_open+0x1c2/0x310
[ +0.000337] ? __inode_permission+0x5b/0x160
[ +0.000342] ? cifs_uncached_writev_complete+0x3f0/0x3f0 [cifs]
[ +0.000353] vfs_open+0x4f/0x80
[ +0.000334] path_openat+0x66e/0x1770
[ +0.000335] do_filp_open+0x9b/0x110
[ +0.000331] ? __check_object_size+0xaf/0x1b0
[ +0.000332] do_sys_open+0x1bb/0x2c0
[ +0.000329] ? do_sys_open+0x1bb/0x2c0
[ +0.000327] SyS_openat+0x14/0x20
[ +0.000325] do_syscall_64+0x73/0x130
[ +0.000352] entry_SYSCALL_64_after_hwframe+0x3d/0xa2
[ +0.000338] RIP: 0033:0x14620e613c8e
[ +0.000333] RSP: 002b:00007ffcc83c3d30 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
[ +0.000344] RAX: ffffffffffffffda RBX: 000055e697d33260 RCX: 000014620e613c8e
[ +0.000356] RDX: 0000000000000000 RSI: 00007ffcc83c41c0 RDI: 00000000ffffff9c
[ +0.000338] RBP: 000055e6965d798b R08: 0000000000000000 R09: 0000000000000000
[ +0.000338] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000008
[ +0.000337] R13: 000055e6965d798b R14: 0000000000000000 R15: 0000000000000000