msm: mdss: Fix possible buffer overflow in ppp

Correct the limit check for the buffer format and avoid the
possible buffer overflow.

CRs-Fixed: 542730
Signed-off-by: Shivaraj Shetty <shivaraj@codeaurora.org>
Change-Id: I78f86cf8e7dcd0b3f4e124fbbf70353796583a47
writeback: fix occasional slow sync(1)

In case when system contains no dirty pages, wakeup_flusher_threads() will
submit WB_SYNC_NONE writeback for 0 pages so wb_writeback() exits
immediately without doing anything, even though there are dirty inodes in
the system.  Thus sync(1) will write all the dirty inodes from a
WB_SYNC_ALL writeback pass which is slow.

Fix the problem by using get_nr_dirty_pages() in wakeup_flusher_threads()
instead of calculating number of dirty pages manually.  That function also
takes number of dirty inodes into account.

Signed-off-by: Jan Kara <jack@suse.cz>
Reported-by: Paul Taysom <taysom@chromium.org>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/power/powersuspend: default to userspace for now

Signed-off-by: Paul Reioux <reioux@gmail.com>