]> err.no Git - linux-2.6/commit
x86: fence oostores on 64-bit
authorNick Piggin <npiggin@suse.de>
Sat, 13 Oct 2007 01:06:00 +0000 (03:06 +0200)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Sat, 13 Oct 2007 01:41:21 +0000 (18:41 -0700)
commitdf1bdc0667eb3132fe60b3562347ca9133694ee0
tree5d044be900ccc9f13662e1aeae7df6ed108ee43a
parent2b9e0aae1d50e880c58d46788e5e3ebd89d75d62
x86: fence oostores on 64-bit

movnt* instructions are not strongly ordered with respect to other stores,
so if we are to assume stores are strongly ordered in the rest of the 64
bit code, we must fence these off (see similar examples in 32 bit code).

[ The AMD memory ordering document seems to say that nontemporal stores can
  also pass earlier regular stores, so maybe we need sfences _before_
  movnt* everywhere too? ]

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
arch/x86/lib/copy_user_nocache_64.S