From 55aedddb6149ab71bec9f050846855113977b033 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 11 Jul 2019 13:40:55 +0200 Subject: x86/paravirt: Make read_cr2() CALLEE_SAVE The one paravirt read_cr2() implementation (Xen) is actually quite trivial and doesn't need to clobber anything other than the return register. Making read_cr2() CALLEE_SAVE avoids all the PUSH/POP nonsense and allows more convenient use from assembly. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner Reviewed-by: Juergen Gross Cc: bp@alien8.de Cc: rostedt@goodmis.org Cc: luto@kernel.org Cc: torvalds@linux-foundation.org Cc: hpa@zytor.com Cc: dave.hansen@linux.intel.com Cc: zhe.he@windriver.com Cc: joel@joelfernandes.org Cc: devel@etsukata.com Link: https://lkml.kernel.org/r/20190711114335.887392493@infradead.org --- arch/x86/xen/xen-ops.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'arch/x86/xen/xen-ops.h') diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h index 2f111f47ba98..45a441c33d6d 100644 --- a/arch/x86/xen/xen-ops.h +++ b/arch/x86/xen/xen-ops.h @@ -134,6 +134,9 @@ __visible void xen_irq_disable_direct(void); __visible unsigned long xen_save_fl_direct(void); __visible void xen_restore_fl_direct(unsigned long); +__visible unsigned long xen_read_cr2(void); +__visible unsigned long xen_read_cr2_direct(void); + /* These are not functions, and cannot be called normally */ __visible void xen_iret(void); __visible void xen_sysret32(void); -- cgit v1.2.3