From: Jeremy Fitzhardinge <jeremy@goop.org>
Date: Wed, 25 Jun 2008 04:19:26 +0000 (-0400)
Subject: x86/paravirt: split sysret and sysexit
X-Git-Tag: v2.6.27-rc1~1106^2~126
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d75cd22fdd5f7d203fb60014d426942df33dd9a6;p=pandora-kernel.git

x86/paravirt: split sysret and sysexit

Don't conflate sysret and sysexit; they're different instructions with
different semantics, and may be in use at the same time (at least
within the same kernel, depending on whether its an Intel or AMD
system).

sysexit - just return to userspace, does no register restoration of
    any kind; must explicitly atomically enable interrupts.

sysret - reloads flags from r11, so no need to explicitly enable
    interrupts on 64-bit, responsible for restoring usermode %gs

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citirx.com>
Cc: xen-devel <xen-devel@lists.xensource.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---

Reading git-diff-tree failed