b24fdd0f1c
commit f43b9876e857c739d407bc56df288b0ebe1a9164 upstream. Do fine-grained Kconfig for all the various retbleed parts. NOTE: if your compiler doesn't support return thunks this will silently 'upgrade' your mitigation to IBPB, you might not like this. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> [cascardo: there is no CONFIG_OBJTOOL] [cascardo: objtool calling and option parsing has changed] Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> [bwh: Backported to 5.10: - In scripts/Makefile.build, add the objtool option with an ifdef block, same as for other options - Adjust filename, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
47 lines
1.1 KiB
C
47 lines
1.1 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _ASM_X86_LINKAGE_H
|
|
#define _ASM_X86_LINKAGE_H
|
|
|
|
#include <linux/stringify.h>
|
|
|
|
#undef notrace
|
|
#define notrace __attribute__((no_instrument_function))
|
|
|
|
#ifdef CONFIG_X86_32
|
|
#define asmlinkage CPP_ASMLINKAGE __attribute__((regparm(0)))
|
|
#endif /* CONFIG_X86_32 */
|
|
|
|
#ifdef __ASSEMBLY__
|
|
|
|
#if defined(CONFIG_X86_64) || defined(CONFIG_X86_ALIGNMENT_16)
|
|
#define __ALIGN .p2align 4, 0x90
|
|
#define __ALIGN_STR __stringify(__ALIGN)
|
|
#endif
|
|
|
|
#if defined(CONFIG_RETHUNK) && !defined(__DISABLE_EXPORTS) && !defined(BUILD_VDSO)
|
|
#define RET jmp __x86_return_thunk
|
|
#else /* CONFIG_RETPOLINE */
|
|
#ifdef CONFIG_SLS
|
|
#define RET ret; int3
|
|
#else
|
|
#define RET ret
|
|
#endif
|
|
#endif /* CONFIG_RETPOLINE */
|
|
|
|
#else /* __ASSEMBLY__ */
|
|
|
|
#if defined(CONFIG_RETHUNK) && !defined(__DISABLE_EXPORTS) && !defined(BUILD_VDSO)
|
|
#define ASM_RET "jmp __x86_return_thunk\n\t"
|
|
#else /* CONFIG_RETPOLINE */
|
|
#ifdef CONFIG_SLS
|
|
#define ASM_RET "ret; int3\n\t"
|
|
#else
|
|
#define ASM_RET "ret\n\t"
|
|
#endif
|
|
#endif /* CONFIG_RETPOLINE */
|
|
|
|
#endif /* __ASSEMBLY__ */
|
|
|
|
#endif /* _ASM_X86_LINKAGE_H */
|
|
|