x86, asmlinkage, paravirt: Don't rely on local assembler labels
authorAndi Kleen <ak@linux.intel.com>
Tue, 22 Oct 2013 16:07:55 +0000 (09:07 -0700)
committerH. Peter Anvin <hpa@linux.intel.com>
Thu, 30 Jan 2014 06:17:17 +0000 (22:17 -0800)
The paravirt patching code assumes that it can reference a
local assembler label between two different top level assembler
statements. This does not work with LTO
where the assembler code may end up in different assembler files.

Replace it with extern / global /asm linkage labels.

This also removes one redundant copy of the macro.

Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1382458079-24450-4-git-send-email-andi@firstfloor.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
arch/x86/include/asm/paravirt_types.h

index aab8f671b523f7801608c880225558d425889061..7549b8b369e47cf540d5dbb747b870ab42eb5b6a 100644 (file)
@@ -388,10 +388,11 @@ extern struct pv_lock_ops pv_lock_ops;
        _paravirt_alt(insn_string, "%c[paravirt_typenum]", "%c[paravirt_clobber]")
 
 /* Simple instruction patching code. */
-#define DEF_NATIVE(ops, name, code)                                    \
-       extern const char start_##ops##_##name[] __visible,             \
-                         end_##ops##_##name[] __visible;               \
-       asm("start_" #ops "_" #name ": " code "; end_" #ops "_" #name ":")
+#define NATIVE_LABEL(a,x,b) "\n\t.globl " a #x "_" #b "\n" a #x "_" #b ":\n\t"
+
+#define DEF_NATIVE(ops, name, code)                                    \
+       __visible extern const char start_##ops##_##name[], end_##ops##_##name[];       \
+       asm(NATIVE_LABEL("start_", ops, name) code NATIVE_LABEL("end_", ops, name))
 
 unsigned paravirt_patch_nop(void);
 unsigned paravirt_patch_ident_32(void *insnbuf, unsigned len);