tree 91d1033d6699e28393c7a2cae63727ac22db92ac
parent b5637e65ee2cecd344b1f8ff750013f697d3ae16
author Andy Whitcroft <apw@shadowen.org> 1178488173 -0700
committer Linus Torvalds <torvalds@woody.linux-foundation.org> 1178565173 -0700

tty_register_driver: only allocate tty instances when defined

If device->num is zero we attempt to kmalloc() zero bytes.  When SLUB is
enabled this returns a null pointer and take that as an allocation failure
and fail the device register.  Check for no devices and avoid the
allocation.

[akpm: opportunistic kzalloc() conversion]
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>