linux-sg2042/arch/x86/include/asm/kprobes.h

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#ifndef _ASM_X86_KPROBES_H
#define _ASM_X86_KPROBES_H
/*
* Kernel Probes (KProbes)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* Copyright (C) IBM Corporation, 2002, 2004
*
* See arch/x86/kernel/kprobes.c for x86 kprobes history.
*/
#include <linux/types.h>
#include <linux/ptrace.h>
#include <linux/percpu.h>
#include <asm/insn.h>
#define __ARCH_WANT_KPROBES_INSN_SLOT
#define ARCH_SUPPORTS_KPROBES_ON_FTRACE
struct pt_regs;
struct kprobe;
typedef u8 kprobe_opcode_t;
#define BREAKPOINT_INSTRUCTION 0xcc
#define RELATIVEJUMP_OPCODE 0xe9
kprobes/x86: Support kprobes jump optimization on x86 Introduce x86 arch-specific optimization code, which supports both of x86-32 and x86-64. This code also supports safety checking, which decodes whole of a function in which probe is inserted, and checks following conditions before optimization: - The optimized instructions which will be replaced by a jump instruction don't straddle the function boundary. - There is no indirect jump instruction, because it will jumps into the address range which is replaced by jump operand. - There is no jump/loop instruction which jumps into the address range which is replaced by jump operand. - Don't optimize kprobes if it is in functions into which fixup code will jumps. This uses text_poke_multibyte() which doesn't support modifying code on NMI/MCE handler. However, since kprobes itself doesn't support NMI/MCE code probing, it's not a problem. Changes in v9: - Use *_text_reserved() for checking the probe can be optimized. - Verify jump address range is in 2G range when preparing slot. - Backup original code when switching optimized buffer, instead of preparing buffer, because there can be int3 of other probes in preparing phase. - Check kprobe is disabled in arch_check_optimized_kprobe(). - Strictly check indirect jump opcodes (ff /4, ff /5). Changes in v6: - Split stop_machine-based jump patching code. - Update comments and coding style. Changes in v5: - Introduce stop_machine-based jump replacing. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Anders Kaseorg <andersk@ksplice.com> Cc: Tim Abbott <tabbott@ksplice.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Jason Baron <jbaron@redhat.com> Cc: Mathieu Desnoyers <compudj@krystal.dyndns.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> LKML-Reference: <20100225133446.6725.78994.stgit@localhost6.localdomain6> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-25 21:34:46 +08:00
#define RELATIVEJUMP_SIZE 5
#define RELATIVECALL_OPCODE 0xe8
#define RELATIVE_ADDR_SIZE 4
#define MAX_STACK_SIZE 64
#define MIN_STACK_SIZE(ADDR) \
(((MAX_STACK_SIZE) < (((unsigned long)current_thread_info()) + \
THREAD_SIZE - (unsigned long)(ADDR))) \
? (MAX_STACK_SIZE) \
: (((unsigned long)current_thread_info()) + \
THREAD_SIZE - (unsigned long)(ADDR)))
#define flush_insn_slot(p) do { } while (0)
kprobes/x86: Support kprobes jump optimization on x86 Introduce x86 arch-specific optimization code, which supports both of x86-32 and x86-64. This code also supports safety checking, which decodes whole of a function in which probe is inserted, and checks following conditions before optimization: - The optimized instructions which will be replaced by a jump instruction don't straddle the function boundary. - There is no indirect jump instruction, because it will jumps into the address range which is replaced by jump operand. - There is no jump/loop instruction which jumps into the address range which is replaced by jump operand. - Don't optimize kprobes if it is in functions into which fixup code will jumps. This uses text_poke_multibyte() which doesn't support modifying code on NMI/MCE handler. However, since kprobes itself doesn't support NMI/MCE code probing, it's not a problem. Changes in v9: - Use *_text_reserved() for checking the probe can be optimized. - Verify jump address range is in 2G range when preparing slot. - Backup original code when switching optimized buffer, instead of preparing buffer, because there can be int3 of other probes in preparing phase. - Check kprobe is disabled in arch_check_optimized_kprobe(). - Strictly check indirect jump opcodes (ff /4, ff /5). Changes in v6: - Split stop_machine-based jump patching code. - Update comments and coding style. Changes in v5: - Introduce stop_machine-based jump replacing. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Anders Kaseorg <andersk@ksplice.com> Cc: Tim Abbott <tabbott@ksplice.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Jason Baron <jbaron@redhat.com> Cc: Mathieu Desnoyers <compudj@krystal.dyndns.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> LKML-Reference: <20100225133446.6725.78994.stgit@localhost6.localdomain6> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-25 21:34:46 +08:00
/* optinsn template addresses */
extern kprobe_opcode_t optprobe_template_entry;
extern kprobe_opcode_t optprobe_template_val;
extern kprobe_opcode_t optprobe_template_call;
extern kprobe_opcode_t optprobe_template_end;
#define MAX_OPTIMIZED_LENGTH (MAX_INSN_SIZE + RELATIVE_ADDR_SIZE)
#define MAX_OPTINSN_SIZE \
(((unsigned long)&optprobe_template_end - \
(unsigned long)&optprobe_template_entry) + \
MAX_OPTIMIZED_LENGTH + RELATIVEJUMP_SIZE)
extern const int kretprobe_blacklist_size;
void arch_remove_kprobe(struct kprobe *p);
void kretprobe_trampoline(void);
/* Architecture specific copy of original instruction*/
struct arch_specific_insn {
/* copy of the original instruction */
kprobe_opcode_t *insn;
/*
* boostable = -1: This instruction type is not boostable.
* boostable = 0: This instruction type is boostable.
* boostable = 1: This instruction has been boosted: we have
* added a relative jump after the instruction copy in insn,
* so no single-step and fixup are needed (unless there's
* a post_handler or break_handler).
*/
int boostable;
};
kprobes/x86: Support kprobes jump optimization on x86 Introduce x86 arch-specific optimization code, which supports both of x86-32 and x86-64. This code also supports safety checking, which decodes whole of a function in which probe is inserted, and checks following conditions before optimization: - The optimized instructions which will be replaced by a jump instruction don't straddle the function boundary. - There is no indirect jump instruction, because it will jumps into the address range which is replaced by jump operand. - There is no jump/loop instruction which jumps into the address range which is replaced by jump operand. - Don't optimize kprobes if it is in functions into which fixup code will jumps. This uses text_poke_multibyte() which doesn't support modifying code on NMI/MCE handler. However, since kprobes itself doesn't support NMI/MCE code probing, it's not a problem. Changes in v9: - Use *_text_reserved() for checking the probe can be optimized. - Verify jump address range is in 2G range when preparing slot. - Backup original code when switching optimized buffer, instead of preparing buffer, because there can be int3 of other probes in preparing phase. - Check kprobe is disabled in arch_check_optimized_kprobe(). - Strictly check indirect jump opcodes (ff /4, ff /5). Changes in v6: - Split stop_machine-based jump patching code. - Update comments and coding style. Changes in v5: - Introduce stop_machine-based jump replacing. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Anders Kaseorg <andersk@ksplice.com> Cc: Tim Abbott <tabbott@ksplice.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Jason Baron <jbaron@redhat.com> Cc: Mathieu Desnoyers <compudj@krystal.dyndns.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> LKML-Reference: <20100225133446.6725.78994.stgit@localhost6.localdomain6> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-25 21:34:46 +08:00
struct arch_optimized_insn {
/* copy of the original instructions */
kprobe_opcode_t copied_insn[RELATIVE_ADDR_SIZE];
/* detour code buffer */
kprobe_opcode_t *insn;
/* the size of instructions copied to detour code buffer */
size_t size;
};
/* Return true (!0) if optinsn is prepared for optimization. */
static inline int arch_prepared_optinsn(struct arch_optimized_insn *optinsn)
{
return optinsn->size;
}
struct prev_kprobe {
struct kprobe *kp;
unsigned long status;
unsigned long old_flags;
unsigned long saved_flags;
};
/* per-cpu kprobe control block */
struct kprobe_ctlblk {
unsigned long kprobe_status;
unsigned long kprobe_old_flags;
unsigned long kprobe_saved_flags;
unsigned long *jprobe_saved_sp;
struct pt_regs jprobe_saved_regs;
kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
struct prev_kprobe prev_kprobe;
};
extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
extern int kprobe_exceptions_notify(struct notifier_block *self,
unsigned long val, void *data);
#endif /* _ASM_X86_KPROBES_H */