[Drbd-dev] simplify procfs code for seq_file instances V2

[David Howells]

Note that your kernel hits the:

	inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage.
	swapper/0/0 [HC1[1]:SC0[0]:HE0:SE1] takes:
		(ptrval) (fs_reclaim){?.+.}, at: fs_reclaim_acquire+0x12/0x35
	{HARDIRQ-ON-W} state was registered at:
	  fs_reclaim_acquire+0x32/0x35
	  kmem_cache_alloc_node_trace+0x49/0x2cf
	  alloc_worker+0x1d/0x49
	  init_rescuer.part.7+0x19/0x8f
	  workqueue_init+0xc0/0x1fe
	  kernel_init_freeable+0xdc/0x433
	  kernel_init+0xa/0xf5
	  ret_from_fork+0x24/0x30

bug, as described here:

	https://groups.google.com/forum/#!msg/syzkaller-bugs/sJC3Y3hOM08/aO3z9JXoAgAJ

David