xen64: save lots of registers
authorJeremy Fitzhardinge <jeremy@goop.org>
Tue, 8 Jul 2008 22:07:12 +0000 (15:07 -0700)
committerIngo Molnar <mingo@elte.hu>
Wed, 16 Jul 2008 09:05:23 +0000 (11:05 +0200)
commitc24481e9da2c7bc8aafab46e0bc64821244a24a6
tree50f5a7de7e7be85a70dce9ee221ebc72f861efd9
parentc05f1cfaba846dfbd4a67e348087d32326288fe0
xen64: save lots of registers

The Xen hypercall interface is allowed to trash any or all of the
argument registers, so we need to be careful that the kernel state
isn't damaged.  On 32-bit kernels, the hypercall parameter registers
same as a regparm function call, so we've got away without explicit
clobbering so far.  The 64-bit ABI defines lots of caller-save
registers, so save them all for safety.  We can trim this set later by
re-distributing the responsibility for saving all these registers.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.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>
include/asm-x86/paravirt.h