Revert "x86 get_unmapped_area(): use proper mmap base for bottom-up direction"
authorLinus Torvalds <torvalds@linux-foundation.org>
Thu, 22 Aug 2013 16:13:06 +0000 (09:13 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 22 Aug 2013 17:18:44 +0000 (10:18 -0700)
commit5ea80f76a56605a190a7ea16846c82aa63dbd0aa
tree99e6547e8bbbcb3187676bb7a002be9d24c6b53e
parentd936d2d452ca1848cc4b397bdfb96d4278b9f934
Revert "x86 get_unmapped_area(): use proper mmap base for bottom-up direction"

This reverts commit df54d6fa54275ce59660453e29d1228c2b45a826.

The commit isn't necessarily wrong, but because it recalculates the
random mmap_base every time, it seems to confuse user memory allocators
that expect contiguous mmap allocations even when the mmap address isn't
specified.

In particular, the MATLAB Java runtime seems to be unhappy. See

  https://bugzilla.kernel.org/show_bug.cgi?id=60774

So we'll want to apply the random offset only once, and Radu has a patch
for that.  Revert this older commit in order to apply the other one.

Reported-by: Jeff Shorey <shoreyjeff@gmail.com>
Cc: Radu Caragea <sinaelgl@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
arch/x86/kernel/sys_x86_64.c
arch/x86/mm/mmap.c
include/linux/sched.h