Imre Deak 954dc41937 wait: fix false timeouts when using wait_event_timeout() ... commit 4c663cfc52 upstream. Many callers of the wait_event_timeout() and wait_event_interruptible_timeout() expect that the return value will be positive if the specified condition becomes true before the timeout elapses. However, at the moment this isn't guaranteed. If the wake-up handler is delayed enough, the time remaining until timeout will be calculated as 0 - and passed back as a return value - even if the condition became true before the timeout has passed. Fix this by returning at least 1 if the condition becomes true. This semantic is in line with what wait_for_condition_timeout() does; see commit bb10ed09 ("sched: fix wait_for_completion_timeout() spurious failure under heavy load"). Daniel said "We have 3 instances of this bug in drm/i915. One case even where we switch between the interruptible and not interruptible wait_event_timeout variants, foolishly presuming they have the same semantics. I very much like this." One such bug is reported at https://bugs.freedesktop.org/show_bug.cgi?id=64133 Signed-off-by: Imre Deak <imre.deak@intel.com> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Jens Axboe <axboe@kernel.dk> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Dave Jones <davej@redhat.com> Cc: Lukas Czerner <lczerner@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2013-06-07 12:49:14 -07:00
..
acpi
asm-generic	mm: allow arch code to control the user page table ceiling	2013-05-07 19:51:55 -07:00
crypto
drm	drm/radeon: add new richland pci ids	2013-05-11 13:48:14 -07:00
keys
linux	wait: fix false timeouts when using wait_event_timeout()	2013-06-07 12:49:14 -07:00
math-emu
media
misc
mtd
net	ipv6: do not clear pinet6 field	2013-05-19 10:54:47 -07:00
pcmcia
rdma	infiniband: pass rdma_cm module to netlink_dump_start	2012-10-28 10:14:15 -07:00
rxrpc
scsi
sound	ALSA: Add a reference counter to card instance	2012-11-17 13:16:13 -08:00
target	target: Add link_magic for fabric allow_link destination target_items	2013-01-21 11:45:24 -08:00
trace	xen/mmu: Use Xen specific TLB flush instead of the generic one.	2012-11-17 13:15:54 -08:00
video	atmel_lcdfb: fix 16-bpp modes on older SOCs	2013-03-20 13:05:00 -07:00
xen	xen/blkback: correctly respond to unknown, non-native requests	2013-04-05 10:04:18 -07:00
Kbuild