MIPS: kprobe: Add support.
This patch is based on previous work by Sony and Himanshu Chauhan. I have done some cleanup and implemented JProbes and KRETPROBES. The KRETPROBES part is pretty much copied verbatim from powerpc. A possible future enhance might be to factor out the common code. Signed-off-by: David Daney <ddaney@caviumnetworks.com> Cc: Himanshu Chauhan <hschauhan@nulltrace.org> To: linux-mips@linux-mips.org To: ananth@in.ibm.com, To: anil.s.keshavamurthy@intel.com To: davem@davemloft.net To: masami.hiramatsu.pt@hitachi.com Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/1525/ Patchwork: https://patchwork.linux-mips.org/patch/1530/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This commit is contained in:
David Daney
Ralf Baechle
Родитель
2ea6399f55
Коммит
c1bf207d6e
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@ -10,6 +10,8 @@ config MIPS
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select HAVE_DYNAMIC_FTRACE
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select HAVE_FTRACE_MCOUNT_RECORD
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select HAVE_FUNCTION_GRAPH_TRACER
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select HAVE_KPROBES
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select HAVE_KRETPROBES
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select RTC_LIB if !MACH_LOONGSON
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mainmenu "Linux/MIPS Kernel Configuration"
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@ -259,6 +259,9 @@ endif
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vmlinux.32: vmlinux
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$(OBJCOPY) -O $(32bit-bfd) $(OBJCOPYFLAGS) $< $@
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#obj-$(CONFIG_KPROBES) += kprobes.o
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#
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# The 64-bit ELF tools are pretty broken so at this time we generate 64-bit
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# ELF files from 32-bit files by conversion.
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@ -30,6 +30,8 @@
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#define BRK_BUG 512 /* Used by BUG() */
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#define BRK_KDB 513 /* Used in KDB_ENTER() */
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#define BRK_MEMU 514 /* Used by FPU emulator */
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#define BRK_KPROBE_BP 515 /* Kprobe break */
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#define BRK_KPROBE_SSTEPBP 516 /* Kprobe single step software implementation */
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#define BRK_MULOVF 1023 /* Multiply overflow */
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#endif /* __ASM_BREAK_H */
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@ -8,6 +8,9 @@ enum die_val {
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DIE_FP,
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DIE_TRAP,
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DIE_RI,
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DIE_PAGE_FAULT,
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DIE_BREAK,
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DIE_SSTEPBP
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};
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#endif /* _ASM_MIPS_KDEBUG_H */
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@ -0,0 +1,92 @@
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/*
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* Kernel Probes (KProbes)
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* include/asm-mips/kprobes.h
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*
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* Copyright 2006 Sony Corp.
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* Copyright 2010 Cavium Networks
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; version 2 of the License.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#ifndef _ASM_KPROBES_H
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#define _ASM_KPROBES_H
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#include <linux/ptrace.h>
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#include <linux/types.h>
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#include <asm/cacheflush.h>
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#include <asm/kdebug.h>
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#include <asm/inst.h>
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#define __ARCH_WANT_KPROBES_INSN_SLOT
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struct kprobe;
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struct pt_regs;
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typedef union mips_instruction kprobe_opcode_t;
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#define MAX_INSN_SIZE 2
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#define flush_insn_slot(p) \
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do { \
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flush_icache_range((unsigned long)p->addr, \
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(unsigned long)p->addr + \
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(MAX_INSN_SIZE * sizeof(kprobe_opcode_t))); \
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} while (0)
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#define kretprobe_blacklist_size 0
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void arch_remove_kprobe(struct kprobe *p);
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/* Architecture specific copy of original instruction*/
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struct arch_specific_insn {
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/* copy of the original instruction */
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kprobe_opcode_t *insn;
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};
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struct prev_kprobe {
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struct kprobe *kp;
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unsigned long status;
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unsigned long old_SR;
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unsigned long saved_SR;
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unsigned long saved_epc;
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};
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#define MAX_JPROBES_STACK_SIZE 128
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#define MAX_JPROBES_STACK_ADDR \
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(((unsigned long)current_thread_info()) + THREAD_SIZE - 32 - sizeof(struct pt_regs))
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#define MIN_JPROBES_STACK_SIZE(ADDR) \
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((((ADDR) + MAX_JPROBES_STACK_SIZE) > MAX_JPROBES_STACK_ADDR) \
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? MAX_JPROBES_STACK_ADDR - (ADDR) \
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: MAX_JPROBES_STACK_SIZE)
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/* per-cpu kprobe control block */
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struct kprobe_ctlblk {
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unsigned long kprobe_status;
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unsigned long kprobe_old_SR;
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unsigned long kprobe_saved_SR;
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unsigned long kprobe_saved_epc;
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unsigned long jprobe_saved_sp;
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struct pt_regs jprobe_saved_regs;
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u8 jprobes_stack[MAX_JPROBES_STACK_SIZE];
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struct prev_kprobe prev_kprobe;
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};
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extern int kprobe_exceptions_notify(struct notifier_block *self,
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unsigned long val, void *data);
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#endif /* _ASM_KPROBES_H */
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@ -76,6 +76,7 @@ obj-$(CONFIG_IRQ_TXX9) += irq_txx9.o
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obj-$(CONFIG_IRQ_GT641XX) += irq-gt641xx.o
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obj-$(CONFIG_IRQ_GIC) += irq-gic.o
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obj-$(CONFIG_KPROBES) += kprobes.o
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obj-$(CONFIG_32BIT) += scall32-o32.o
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obj-$(CONFIG_64BIT) += scall64-64.o
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obj-$(CONFIG_MIPS32_COMPAT) += linux32.o ptrace32.o signal32.o
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@ -0,0 +1,557 @@
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/*
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* Kernel Probes (KProbes)
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* arch/mips/kernel/kprobes.c
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*
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* Copyright 2006 Sony Corp.
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* Copyright 2010 Cavium Networks
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*
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* Some portions copied from the powerpc version.
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*
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* Copyright (C) IBM Corporation, 2002, 2004
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; version 2 of the License.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#include <linux/kprobes.h>
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#include <linux/preempt.h>
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#include <linux/kdebug.h>
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#include <linux/slab.h>
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#include <asm/ptrace.h>
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#include <asm/break.h>
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#include <asm/inst.h>
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static const union mips_instruction breakpoint_insn = {
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.b_format = {
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.opcode = spec_op,
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.code = BRK_KPROBE_BP,
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.func = break_op
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}
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};
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static const union mips_instruction breakpoint2_insn = {
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.b_format = {
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.opcode = spec_op,
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.code = BRK_KPROBE_SSTEPBP,
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.func = break_op
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}
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};
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DEFINE_PER_CPU(struct kprobe *, current_kprobe);
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DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
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static int __kprobes insn_has_delayslot(union mips_instruction insn)
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{
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switch (insn.i_format.opcode) {
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/*
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* This group contains:
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* jr and jalr are in r_format format.
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*/
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case spec_op:
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switch (insn.r_format.func) {
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case jr_op:
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case jalr_op:
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break;
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default:
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goto insn_ok;
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}
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/*
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* This group contains:
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* bltz_op, bgez_op, bltzl_op, bgezl_op,
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* bltzal_op, bgezal_op, bltzall_op, bgezall_op.
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*/
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case bcond_op:
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/*
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* These are unconditional and in j_format.
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*/
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case jal_op:
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case j_op:
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/*
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* These are conditional and in i_format.
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*/
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case beq_op:
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case beql_op:
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case bne_op:
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case bnel_op:
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case blez_op:
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case blezl_op:
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case bgtz_op:
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case bgtzl_op:
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/*
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* These are the FPA/cp1 branch instructions.
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*/
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case cop1_op:
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#ifdef CONFIG_CPU_CAVIUM_OCTEON
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case lwc2_op: /* This is bbit0 on Octeon */
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case ldc2_op: /* This is bbit032 on Octeon */
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case swc2_op: /* This is bbit1 on Octeon */
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case sdc2_op: /* This is bbit132 on Octeon */
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#endif
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return 1;
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default:
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break;
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}
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insn_ok:
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return 0;
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}
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int __kprobes arch_prepare_kprobe(struct kprobe *p)
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{
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union mips_instruction insn;
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union mips_instruction prev_insn;
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int ret = 0;
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prev_insn = p->addr[-1];
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insn = p->addr[0];
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if (insn_has_delayslot(insn) || insn_has_delayslot(prev_insn)) {
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pr_notice("Kprobes for branch and jump instructions are not supported\n");
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ret = -EINVAL;
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goto out;
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}
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/* insn: must be on special executable page on mips. */
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p->ainsn.insn = get_insn_slot();
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if (!p->ainsn.insn) {
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ret = -ENOMEM;
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goto out;
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}
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/*
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* In the kprobe->ainsn.insn[] array we store the original
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* instruction at index zero and a break trap instruction at
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* index one.
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*/
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memcpy(&p->ainsn.insn[0], p->addr, sizeof(kprobe_opcode_t));
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p->ainsn.insn[1] = breakpoint2_insn;
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p->opcode = *p->addr;
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out:
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return ret;
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}
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void __kprobes arch_arm_kprobe(struct kprobe *p)
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{
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*p->addr = breakpoint_insn;
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flush_insn_slot(p);
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}
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void __kprobes arch_disarm_kprobe(struct kprobe *p)
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{
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*p->addr = p->opcode;
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flush_insn_slot(p);
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}
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void __kprobes arch_remove_kprobe(struct kprobe *p)
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{
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free_insn_slot(p->ainsn.insn, 0);
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}
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static void save_previous_kprobe(struct kprobe_ctlblk *kcb)
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{
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kcb->prev_kprobe.kp = kprobe_running();
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kcb->prev_kprobe.status = kcb->kprobe_status;
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kcb->prev_kprobe.old_SR = kcb->kprobe_old_SR;
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kcb->prev_kprobe.saved_SR = kcb->kprobe_saved_SR;
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kcb->prev_kprobe.saved_epc = kcb->kprobe_saved_epc;
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}
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static void restore_previous_kprobe(struct kprobe_ctlblk *kcb)
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{
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__get_cpu_var(current_kprobe) = kcb->prev_kprobe.kp;
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kcb->kprobe_status = kcb->prev_kprobe.status;
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kcb->kprobe_old_SR = kcb->prev_kprobe.old_SR;
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kcb->kprobe_saved_SR = kcb->prev_kprobe.saved_SR;
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kcb->kprobe_saved_epc = kcb->prev_kprobe.saved_epc;
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}
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static void set_current_kprobe(struct kprobe *p, struct pt_regs *regs,
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struct kprobe_ctlblk *kcb)
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{
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__get_cpu_var(current_kprobe) = p;
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kcb->kprobe_saved_SR = kcb->kprobe_old_SR = (regs->cp0_status & ST0_IE);
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kcb->kprobe_saved_epc = regs->cp0_epc;
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}
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static void prepare_singlestep(struct kprobe *p, struct pt_regs *regs)
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{
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regs->cp0_status &= ~ST0_IE;
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/* single step inline if the instruction is a break */
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if (p->opcode.word == breakpoint_insn.word ||
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p->opcode.word == breakpoint2_insn.word)
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regs->cp0_epc = (unsigned long)p->addr;
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else
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regs->cp0_epc = (unsigned long)&p->ainsn.insn[0];
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}
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static int __kprobes kprobe_handler(struct pt_regs *regs)
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{
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struct kprobe *p;
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int ret = 0;
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kprobe_opcode_t *addr;
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struct kprobe_ctlblk *kcb;
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addr = (kprobe_opcode_t *) regs->cp0_epc;
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/*
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* We don't want to be preempted for the entire
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* duration of kprobe processing
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*/
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preempt_disable();
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kcb = get_kprobe_ctlblk();
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/* Check we're not actually recursing */
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if (kprobe_running()) {
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p = get_kprobe(addr);
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if (p) {
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if (kcb->kprobe_status == KPROBE_HIT_SS &&
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p->ainsn.insn->word == breakpoint_insn.word) {
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regs->cp0_status &= ~ST0_IE;
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regs->cp0_status |= kcb->kprobe_saved_SR;
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goto no_kprobe;
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}
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/*
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* We have reentered the kprobe_handler(), since
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* another probe was hit while within the handler.
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* We here save the original kprobes variables and
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* just single step on the instruction of the new probe
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* without calling any user handlers.
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*/
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save_previous_kprobe(kcb);
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set_current_kprobe(p, regs, kcb);
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kprobes_inc_nmissed_count(p);
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prepare_singlestep(p, regs);
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kcb->kprobe_status = KPROBE_REENTER;
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return 1;
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} else {
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if (addr->word != breakpoint_insn.word) {
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/*
|
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* The breakpoint instruction was removed by
|
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* another cpu right after we hit, no further
|
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* handling of this interrupt is appropriate
|
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*/
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ret = 1;
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goto no_kprobe;
|
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}
|
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p = __get_cpu_var(current_kprobe);
|
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if (p->break_handler && p->break_handler(p, regs))
|
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goto ss_probe;
|
||||
}
|
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goto no_kprobe;
|
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}
|
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|
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p = get_kprobe(addr);
|
||||
if (!p) {
|
||||
if (addr->word != breakpoint_insn.word) {
|
||||
/*
|
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* The breakpoint instruction was removed right
|
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* after we hit it. Another cpu has removed
|
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* either a probepoint or a debugger breakpoint
|
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* at this address. In either case, no further
|
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* handling of this interrupt is appropriate.
|
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*/
|
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ret = 1;
|
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}
|
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/* Not one of ours: let kernel handle it */
|
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goto no_kprobe;
|
||||
}
|
||||
|
||||
set_current_kprobe(p, regs, kcb);
|
||||
kcb->kprobe_status = KPROBE_HIT_ACTIVE;
|
||||
|
||||
if (p->pre_handler && p->pre_handler(p, regs)) {
|
||||
/* handler has already set things up, so skip ss setup */
|
||||
return 1;
|
||||
}
|
||||
|
||||
ss_probe:
|
||||
prepare_singlestep(p, regs);
|
||||
kcb->kprobe_status = KPROBE_HIT_SS;
|
||||
return 1;
|
||||
|
||||
no_kprobe:
|
||||
preempt_enable_no_resched();
|
||||
return ret;
|
||||
|
||||
}
|
||||
|
||||
/*
|
||||
* Called after single-stepping. p->addr is the address of the
|
||||
* instruction whose first byte has been replaced by the "break 0"
|
||||
* instruction. To avoid the SMP problems that can occur when we
|
||||
* temporarily put back the original opcode to single-step, we
|
||||
* single-stepped a copy of the instruction. The address of this
|
||||
* copy is p->ainsn.insn.
|
||||
*
|
||||
* This function prepares to return from the post-single-step
|
||||
* breakpoint trap.
|
||||
*/
|
||||
static void __kprobes resume_execution(struct kprobe *p,
|
||||
struct pt_regs *regs,
|
||||
struct kprobe_ctlblk *kcb)
|
||||
{
|
||||
unsigned long orig_epc = kcb->kprobe_saved_epc;
|
||||
regs->cp0_epc = orig_epc + 4;
|
||||
}
|
||||
|
||||
static inline int post_kprobe_handler(struct pt_regs *regs)
|
||||
{
|
||||
struct kprobe *cur = kprobe_running();
|
||||
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
|
||||
|
||||
if (!cur)
|
||||
return 0;
|
||||
|
||||
if ((kcb->kprobe_status != KPROBE_REENTER) && cur->post_handler) {
|
||||
kcb->kprobe_status = KPROBE_HIT_SSDONE;
|
||||
cur->post_handler(cur, regs, 0);
|
||||
}
|
||||
|
||||
resume_execution(cur, regs, kcb);
|
||||
|
||||
regs->cp0_status |= kcb->kprobe_saved_SR;
|
||||
|
||||
/* Restore back the original saved kprobes variables and continue. */
|
||||
if (kcb->kprobe_status == KPROBE_REENTER) {
|
||||
restore_previous_kprobe(kcb);
|
||||
goto out;
|
||||
}
|
||||
reset_current_kprobe();
|
||||
out:
|
||||
preempt_enable_no_resched();
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
||||
static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
|
||||
{
|
||||
struct kprobe *cur = kprobe_running();
|
||||
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
|
||||
|
||||
if (cur->fault_handler && cur->fault_handler(cur, regs, trapnr))
|
||||
return 1;
|
||||
|
||||
if (kcb->kprobe_status & KPROBE_HIT_SS) {
|
||||
resume_execution(cur, regs, kcb);
|
||||
regs->cp0_status |= kcb->kprobe_old_SR;
|
||||
|
||||
reset_current_kprobe();
|
||||
preempt_enable_no_resched();
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Wrapper routine for handling exceptions.
|
||||
*/
|
||||
int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
|
||||
unsigned long val, void *data)
|
||||
{
|
||||
|
||||
struct die_args *args = (struct die_args *)data;
|
||||
int ret = NOTIFY_DONE;
|
||||
|
||||
switch (val) {
|
||||
case DIE_BREAK:
|
||||
if (kprobe_handler(args->regs))
|
||||
ret = NOTIFY_STOP;
|
||||
break;
|
||||
case DIE_SSTEPBP:
|
||||
if (post_kprobe_handler(args->regs))
|
||||
ret = NOTIFY_STOP;
|
||||
break;
|
||||
|
||||
case DIE_PAGE_FAULT:
|
||||
/* kprobe_running() needs smp_processor_id() */
|
||||
preempt_disable();
|
||||
|
||||
if (kprobe_running()
|
||||
&& kprobe_fault_handler(args->regs, args->trapnr))
|
||||
ret = NOTIFY_STOP;
|
||||
preempt_enable();
|
||||
break;
|
||||
default:
|
||||
break;
|
||||
}
|
||||
return ret;
|
||||
}
|
||||
|
||||
int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
|
||||
{
|
||||
struct jprobe *jp = container_of(p, struct jprobe, kp);
|
||||
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
|
||||
|
||||
kcb->jprobe_saved_regs = *regs;
|
||||
kcb->jprobe_saved_sp = regs->regs[29];
|
||||
|
||||
memcpy(kcb->jprobes_stack, (void *)kcb->jprobe_saved_sp,
|
||||
MIN_JPROBES_STACK_SIZE(kcb->jprobe_saved_sp));
|
||||
|
||||
regs->cp0_epc = (unsigned long)(jp->entry);
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
||||
/* Defined in the inline asm below. */
|
||||
void jprobe_return_end(void);
|
||||
|
||||
void __kprobes jprobe_return(void)
|
||||
{
|
||||
/* Assembler quirk necessitates this '0,code' business. */
|
||||
asm volatile(
|
||||
"break 0,%0\n\t"
|
||||
".globl jprobe_return_end\n"
|
||||
"jprobe_return_end:\n"
|
||||
: : "n" (BRK_KPROBE_BP) : "memory");
|
||||
}
|
||||
|
||||
int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
|
||||
{
|
||||
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
|
||||
|
||||
if (regs->cp0_epc >= (unsigned long)jprobe_return &&
|
||||
regs->cp0_epc <= (unsigned long)jprobe_return_end) {
|
||||
*regs = kcb->jprobe_saved_regs;
|
||||
memcpy((void *)kcb->jprobe_saved_sp, kcb->jprobes_stack,
|
||||
MIN_JPROBES_STACK_SIZE(kcb->jprobe_saved_sp));
|
||||
preempt_enable_no_resched();
|
||||
|
||||
return 1;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Function return probe trampoline:
|
||||
* - init_kprobes() establishes a probepoint here
|
||||
* - When the probed function returns, this probe causes the
|
||||
* handlers to fire
|
||||
*/
|
||||
static void __used kretprobe_trampoline_holder(void)
|
||||
{
|
||||
asm volatile(
|
||||
".set push\n\t"
|
||||
/* Keep the assembler from reordering and placing JR here. */
|
||||
".set noreorder\n\t"
|
||||
"nop\n\t"
|
||||
".global kretprobe_trampoline\n"
|
||||
"kretprobe_trampoline:\n\t"
|
||||
"nop\n\t"
|
||||
".set pop"
|
||||
: : : "memory");
|
||||
}
|
||||
|
||||
void kretprobe_trampoline(void);
|
||||
|
||||
void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
|
||||
struct pt_regs *regs)
|
||||
{
|
||||
ri->ret_addr = (kprobe_opcode_t *) regs->regs[31];
|
||||
|
||||
/* Replace the return addr with trampoline addr */
|
||||
regs->regs[31] = (unsigned long)kretprobe_trampoline;
|
||||
}
|
||||
|
||||
/*
|
||||
* Called when the probe at kretprobe trampoline is hit
|
||||
*/
|
||||
static int __kprobes trampoline_probe_handler(struct kprobe *p,
|
||||
struct pt_regs *regs)
|
||||
{
|
||||
struct kretprobe_instance *ri = NULL;
|
||||
struct hlist_head *head, empty_rp;
|
||||
struct hlist_node *node, *tmp;
|
||||
unsigned long flags, orig_ret_address = 0;
|
||||
unsigned long trampoline_address = (unsigned long)kretprobe_trampoline;
|
||||
|
||||
INIT_HLIST_HEAD(&empty_rp);
|
||||
kretprobe_hash_lock(current, &head, &flags);
|
||||
|
||||
/*
|
||||
* It is possible to have multiple instances associated with a given
|
||||
* task either because an multiple functions in the call path
|
||||
* have a return probe installed on them, and/or more than one return
|
||||
* return probe was registered for a target function.
|
||||
*
|
||||
* We can handle this because:
|
||||
* - instances are always inserted at the head of the list
|
||||
* - when multiple return probes are registered for the same
|
||||
* function, the first instance's ret_addr will point to the
|
||||
* real return address, and all the rest will point to
|
||||
* kretprobe_trampoline
|
||||
*/
|
||||
hlist_for_each_entry_safe(ri, node, tmp, head, hlist) {
|
||||
if (ri->task != current)
|
||||
/* another task is sharing our hash bucket */
|
||||
continue;
|
||||
|
||||
if (ri->rp && ri->rp->handler)
|
||||
ri->rp->handler(ri, regs);
|
||||
|
||||
orig_ret_address = (unsigned long)ri->ret_addr;
|
||||
recycle_rp_inst(ri, &empty_rp);
|
||||
|
||||
if (orig_ret_address != trampoline_address)
|
||||
/*
|
||||
* This is the real return address. Any other
|
||||
* instances associated with this task are for
|
||||
* other calls deeper on the call stack
|
||||
*/
|
||||
break;
|
||||
}
|
||||
|
||||
kretprobe_assert(ri, orig_ret_address, trampoline_address);
|
||||
instruction_pointer(regs) = orig_ret_address;
|
||||
|
||||
reset_current_kprobe();
|
||||
kretprobe_hash_unlock(current, &flags);
|
||||
preempt_enable_no_resched();
|
||||
|
||||
hlist_for_each_entry_safe(ri, node, tmp, &empty_rp, hlist) {
|
||||
hlist_del(&ri->hlist);
|
||||
kfree(ri);
|
||||
}
|
||||
/*
|
||||
* By returning a non-zero value, we are telling
|
||||
* kprobe_handler() that we don't want the post_handler
|
||||
* to run (and have re-enabled preemption)
|
||||
*/
|
||||
return 1;
|
||||
}
|
||||
|
||||
int __kprobes arch_trampoline_kprobe(struct kprobe *p)
|
||||
{
|
||||
if (p->addr == (kprobe_opcode_t *)kretprobe_trampoline)
|
||||
return 1;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static struct kprobe trampoline_p = {
|
||||
.addr = (kprobe_opcode_t *)kretprobe_trampoline,
|
||||
.pre_handler = trampoline_probe_handler
|
||||
};
|
||||
|
||||
int __init arch_init_kprobes(void)
|
||||
{
|
||||
return register_kprobe(&trampoline_p);
|
||||
}
|
||||
|
|
@ -25,6 +25,7 @@
|
|||
#include <linux/ptrace.h>
|
||||
#include <linux/kgdb.h>
|
||||
#include <linux/kdebug.h>
|
||||
#include <linux/kprobes.h>
|
||||
#include <linux/notifier.h>
|
||||
#include <linux/kdb.h>
|
||||
|
||||
|
|
@ -334,7 +335,7 @@ void show_regs(struct pt_regs *regs)
|
|||
__show_regs((struct pt_regs *)regs);
|
||||
}
|
||||
|
||||
void show_registers(const struct pt_regs *regs)
|
||||
void show_registers(struct pt_regs *regs)
|
||||
{
|
||||
const int field = 2 * sizeof(unsigned long);
|
||||
|
||||
|
|
@ -783,6 +784,25 @@ asmlinkage void do_bp(struct pt_regs *regs)
|
|||
if (bcode >= (1 << 10))
|
||||
bcode >>= 10;
|
||||
|
||||
/*
|
||||
* notify the kprobe handlers, if instruction is likely to
|
||||
* pertain to them.
|
||||
*/
|
||||
switch (bcode) {
|
||||
case BRK_KPROBE_BP:
|
||||
if (notify_die(DIE_BREAK, "debug", regs, bcode, 0, 0) == NOTIFY_STOP)
|
||||
return;
|
||||
else
|
||||
break;
|
||||
case BRK_KPROBE_SSTEPBP:
|
||||
if (notify_die(DIE_SSTEPBP, "single_step", regs, bcode, 0, 0) == NOTIFY_STOP)
|
||||
return;
|
||||
else
|
||||
break;
|
||||
default:
|
||||
break;
|
||||
}
|
||||
|
||||
do_trap_or_bp(regs, bcode, "Break");
|
||||
return;
|
||||
|
||||
|
|
|
|||
|
|
@ -17,6 +17,7 @@
|
|||
#include <linux/mm.h>
|
||||
#include <linux/smp.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/kprobes.h>
|
||||
|
||||
#include <asm/branch.h>
|
||||
#include <asm/mmu_context.h>
|
||||
|
|
@ -24,13 +25,14 @@
|
|||
#include <asm/uaccess.h>
|
||||
#include <asm/ptrace.h>
|
||||
#include <asm/highmem.h> /* For VMALLOC_END */
|
||||
#include <linux/kdebug.h>
|
||||
|
||||
/*
|
||||
* This routine handles page faults. It determines the address,
|
||||
* and the problem, and then passes it off to one of the appropriate
|
||||
* routines.
|
||||
*/
|
||||
asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long write,
|
||||
asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, unsigned long write,
|
||||
unsigned long address)
|
||||
{
|
||||
struct vm_area_struct * vma = NULL;
|
||||
|
|
@ -46,6 +48,17 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long write,
|
|||
field, regs->cp0_epc);
|
||||
#endif
|
||||
|
||||
#ifdef CONFIG_KPROBES
|
||||
/*
|
||||
* This is to notify the fault handler of the kprobes. The
|
||||
* exception code is redundant as it is also carried in REGS,
|
||||
* but we pass it anyhow.
|
||||
*/
|
||||
if (notify_die(DIE_PAGE_FAULT, "page fault", regs, -1,
|
||||
(regs->cp0_cause >> 2) & 0x1f, SIGSEGV) == NOTIFY_STOP)
|
||||
return;
|
||||
#endif
|
||||
|
||||
info.si_code = SEGV_MAPERR;
|
||||
|
||||
/*
|
||||
|
|
|
|||
Загрузка…
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