[PATCH v2 7/8] x86/xen: Add unwind hint annotations

[Josh Poimboeuf]

Add unwind hint annotations to the xen head code so the ORC unwinder can
read head_64.o.

hypercall_page needs empty annotations at 32-byte intervals to match the
'xen_hypercall_*' ELF functions at those locations.

Signed-off-by: Josh Poimboeuf <jpoim...@redhat.com>
---
 arch/x86/xen/xen-head.S | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/x86/xen/xen-head.S b/arch/x86/xen/xen-head.S
index 9753225289e8..124941d09b2b 100644
--- a/arch/x86/xen/xen-head.S
+++ b/arch/x86/xen/xen-head.S
@@ -9,6 +9,7 @@
 #include <asm/boot.h>
 #include <asm/asm.h>
 #include <asm/page_types.h>
+#include <asm/unwind_hints.h>
 
 #include <xen/interface/elfnote.h>
 #include <xen/interface/features.h>
@@ -19,6 +20,7 @@
 #ifdef CONFIG_XEN_PV
        __INIT
 ENTRY(startup_xen)
+       UNWIND_HINT_EMPTY
        cld
 
        /* Clear .bss */
@@ -40,7 +42,10 @@ END(startup_xen)
 .pushsection .text
        .balign PAGE_SIZE
 ENTRY(hypercall_page)
-       .skip PAGE_SIZE
+       .rept (PAGE_SIZE / 32)
+               UNWIND_HINT_EMPTY
+               .skip 32
+       .endr
 
 #define HYPERCALL(n) \
        .equ xen_hypercall_##n, hypercall_page + __HYPERVISOR_##n * 32; \
-- 
2.13.5