Commit 35de5b06 authored by Andy Lutomirski's avatar Andy Lutomirski Committed by Ingo Molnar
Browse files

x86/asm: Stop depending on ptrace.h in alternative.h 



alternative.h pulls in ptrace.h, which means that alternatives can't
be used in anything referenced from ptrace.h, which is a mess.

Break the dependency by pulling text patching helpers into their own
header.

Signed-off-by: default avatarAndy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/99b93b13f2c9eb671f5c98bba4c2cbdc061293a2.1461698311.git.luto@kernel.org


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent ffc5fce9

arch/x86/include/asm/alternative.h

+0 −33
Original line number Diff line number Diff line
@@ -5,7 +5,6 @@ 
#include <linux/stddef.h>

#include <linux/stringify.h>

#include <asm/asm.h>

#include <asm/ptrace.h>



/*

 * Alternative inline assembly for SMP.
@@ -233,36 +232,4 @@ static inline int alternatives_text_reserved(void *start, void *end) 
 */

#define ASM_NO_INPUT_CLOBBER(clbr...) "i" (0) : clbr



struct paravirt_patch_site;

#ifdef CONFIG_PARAVIRT

void apply_paravirt(struct paravirt_patch_site *start,

		    struct paravirt_patch_site *end);

#else

static inline void apply_paravirt(struct paravirt_patch_site *start,

				  struct paravirt_patch_site *end)

{}

#define __parainstructions	NULL

#define __parainstructions_end	NULL

#endif



extern void *text_poke_early(void *addr, const void *opcode, size_t len);



/*

 * Clear and restore the kernel write-protection flag on the local CPU.

 * Allows the kernel to edit read-only pages.

 * Side-effect: any interrupt handler running between save and restore will have

 * the ability to write to read-only pages.

 *

 * Warning:

 * Code patching in the UP case is safe if NMIs and MCE handlers are stopped and

 * no thread can be preempted in the instructions being modified (no iret to an

 * invalid instruction possible) or if the instructions are changed from a

 * consistent state to another consistent state atomically.

 * On the local CPU you need to be protected again NMI or MCE handlers seeing an

 * inconsistent instruction while you patch.

 */

extern void *text_poke(void *addr, const void *opcode, size_t len);

extern int poke_int3_handler(struct pt_regs *regs);

extern void *text_poke_bp(void *addr, const void *opcode, size_t len, void *handler);



#endif /* _ASM_X86_ALTERNATIVE_H */

arch/x86/include/asm/kgdb.h

+2 −0
Original line number Diff line number Diff line
@@ -6,6 +6,8 @@ 
 * Copyright (C) 2008 Wind River Systems, Inc.

 */



#include <asm/ptrace.h>



/*

 * BUFMAX defines the maximum number of characters in inbound/outbound

 * buffers at least NUMREGBYTES*2 are needed for register packets

arch/x86/include/asm/setup.h

+1 −0
Original line number Diff line number Diff line
@@ -6,6 +6,7 @@ 
#define COMMAND_LINE_SIZE 2048



#include <linux/linkage.h>

#include <asm/page_types.h>



#ifdef __i386__

arch/x86/include/asm/text-patching.h

0 → 100644
+40 −0
Original line number Diff line number Diff line 
#ifndef _ASM_X86_TEXT_PATCHING_H

#define _ASM_X86_TEXT_PATCHING_H



#include <linux/types.h>

#include <linux/stddef.h>

#include <asm/ptrace.h>



struct paravirt_patch_site;

#ifdef CONFIG_PARAVIRT

void apply_paravirt(struct paravirt_patch_site *start,

		    struct paravirt_patch_site *end);

#else

static inline void apply_paravirt(struct paravirt_patch_site *start,

				  struct paravirt_patch_site *end)

{}

#define __parainstructions	NULL

#define __parainstructions_end	NULL

#endif



extern void *text_poke_early(void *addr, const void *opcode, size_t len);



/*

 * Clear and restore the kernel write-protection flag on the local CPU.

 * Allows the kernel to edit read-only pages.

 * Side-effect: any interrupt handler running between save and restore will have

 * the ability to write to read-only pages.

 *

 * Warning:

 * Code patching in the UP case is safe if NMIs and MCE handlers are stopped and

 * no thread can be preempted in the instructions being modified (no iret to an

 * invalid instruction possible) or if the instructions are changed from a

 * consistent state to another consistent state atomically.

 * On the local CPU you need to be protected again NMI or MCE handlers seeing an

 * inconsistent instruction while you patch.

 */

extern void *text_poke(void *addr, const void *opcode, size_t len);

extern int poke_int3_handler(struct pt_regs *regs);

extern void *text_poke_bp(void *addr, const void *opcode, size_t len, void *handler);



#endif /* _ASM_X86_TEXT_PATCHING_H */

arch/x86/kernel/alternative.c

+1 −0
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@ 
#include <linux/stop_machine.h>

#include <linux/slab.h>

#include <linux/kdebug.h>

#include <asm/text-patching.h>

#include <asm/alternative.h>

#include <asm/sections.h>

#include <asm/pgtable.h>

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