[RFC v2 04/23] x86: Add macro to get symbol address for PIE support
From: Thomas Garnier <hidden>
Date: 2017-08-10 17:25:56
Also in:
kvm, linux-arch, linux-pm, xen-devel
Subsystem:
the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
Add a new _ASM_GET_PTR macro to fetch a symbol address. It will be used to replace "_ASM_MOV $<symbol>, %dst" code construct that are not compatible with PIE. Signed-off-by: Thomas Garnier <redacted> --- arch/x86/include/asm/asm.h | 13 +++++++++++++ 1 file changed, 13 insertions(+)
diff --git a/arch/x86/include/asm/asm.h b/arch/x86/include/asm/asm.h
index 7a9df3beb89b..bf2842cfb583 100644
--- a/arch/x86/include/asm/asm.h
+++ b/arch/x86/include/asm/asm.h@@ -55,6 +55,19 @@ # define CC_OUT(c) [_cc_ ## c] "=qm" #endif +/* Macros to get a global variable address with PIE support on 64-bit */ +#ifdef CONFIG_X86_32 +#define __ASM_GET_PTR_PRE(_src) __ASM_FORM_COMMA(movl $##_src) +#else +#ifdef __ASSEMBLY__ +#define __ASM_GET_PTR_PRE(_src) __ASM_FORM_COMMA(leaq (_src)(%rip)) +#else +#define __ASM_GET_PTR_PRE(_src) __ASM_FORM_COMMA(leaq (_src)(%%rip)) +#endif +#endif +#define _ASM_GET_PTR(_src, _dst) \ + __ASM_GET_PTR_PRE(_src) __ASM_FORM(_dst) + /* Exception table entry */ #ifdef __ASSEMBLY__ # define _ASM_EXTABLE_HANDLE(from, to, handler) \
--
2.14.0.434.g98096fd7a8-goog
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel