Hi, Andrew
Here is a patch to clean up kprobe's resume_execute() for i386 arch
against linux-2.6.16-rc1 and also appliable against 2.6.16-rc1-mm4.
Before applying kprobe-booster, I'd like to cleanup codes. It is useful
to simplify (and easy to understand) kprobe-booster patch.
Best Regards,
--
Masami HIRAMATSU
2nd Research Dept.
Hitachi, Ltd., Systems Development Laboratory
E-mail: [email protected]
Signed-off-by: Masami Hiramatsu <[email protected]>
kprobes.c | 26 ++++++++++----------------
1 files changed, 10 insertions(+), 16 deletions(-)
diff -Narup a/arch/i386/kernel/kprobes.c b/arch/i386/kernel/kprobes.c
--- a/arch/i386/kernel/kprobes.c 2006-01-24 19:07:26.000000000 +0900
+++ b/arch/i386/kernel/kprobes.c 2006-01-30 18:17:17.000000000 +0900
@@ -350,10 +350,10 @@ static void __kprobes resume_execution(s
struct pt_regs *regs, struct kprobe_ctlblk *kcb)
{
unsigned long *tos = (unsigned long *)®s->esp;
- unsigned long next_eip = 0;
unsigned long copy_eip = (unsigned long)&p->ainsn.insn;
unsigned long orig_eip = (unsigned long)p->addr;
+ regs->eflags &= ~TF_MASK;
switch (p->ainsn.insn[0]) {
case 0x9c: /* pushfl */
*tos &= ~(TF_MASK | IF_MASK);
@@ -363,9 +363,9 @@ static void __kprobes resume_execution(s
case 0xcb:
case 0xc2:
case 0xca:
- regs->eflags &= ~TF_MASK;
- /* eip is already adjusted, no more changes required*/
- return;
+ case 0xea: /* jmp absolute -- eip is correct */
+ /* eip is already adjusted, no more changes required */
+ goto no_change;
case 0xe8: /* call relative - Fix return addr */
*tos = orig_eip + (*tos - copy_eip);
break;
@@ -373,27 +373,21 @@ static void __kprobes resume_execution(s
if ((p->ainsn.insn[1] & 0x30) == 0x10) {
/* call absolute, indirect */
/* Fix return addr; eip is correct. */
- next_eip = regs->eip;
*tos = orig_eip + (*tos - copy_eip);
+ goto no_change;
} else if (((p->ainsn.insn[1] & 0x31) == 0x20) || /* jmp near, absolute indirect */
((p->ainsn.insn[1] & 0x31) == 0x21)) { /* jmp far, absolute indirect */
/* eip is correct. */
- next_eip = regs->eip;
+ goto no_change;
}
- break;
- case 0xea: /* jmp absolute -- eip is correct */
- next_eip = regs->eip;
- break;
default:
break;
}
- regs->eflags &= ~TF_MASK;
- if (next_eip) {
- regs->eip = next_eip;
- } else {
- regs->eip = orig_eip + (regs->eip - copy_eip);
- }
+ regs->eip = orig_eip + (regs->eip - copy_eip);
+
+no_change:
+ return;
}
/*
Hi, Andrew
The kprobe-booster's patches in current -mm tree
(kprobes-clean-up-resume_execute.patch and x86-kprobes-booster.patch)
are under the influence of the NX-protection support patch
which was merged into linus tree(2.6.16-rc5).
So I fixed those patches.
Here is a patch to clean up kprobe's resume_execute() for i386 arch
against linux-2.6.16-rc5.
This patch makes resume_execute() simple, and useful to simplify the
kprobe-booster patch.
Could you replace the previous patches with these patches?
Best Regards,
--
Masami HIRAMATSU
2nd Research Dept.
Hitachi, Ltd., Systems Development Laboratory
E-mail: [email protected]
Signed-off-by: Masami Hiramatsu <[email protected]>
kprobes.c | 26 ++++++++++----------------
1 files changed, 10 insertions(+), 16 deletions(-)
diff -Narup a/arch/i386/kernel/kprobes.c b/arch/i386/kernel/kprobes.c
--- a/arch/i386/kernel/kprobes.c 2006-02-27 16:21:33.000000000 +0900
+++ b/arch/i386/kernel/kprobes.c 2006-02-27 16:30:58.000000000 +0900
@@ -362,10 +362,10 @@ static void __kprobes resume_execution(s
struct pt_regs *regs, struct kprobe_ctlblk *kcb)
{
unsigned long *tos = (unsigned long *)®s->esp;
- unsigned long next_eip = 0;
unsigned long copy_eip = (unsigned long)p->ainsn.insn;
unsigned long orig_eip = (unsigned long)p->addr;
+ regs->eflags &= ~TF_MASK;
switch (p->ainsn.insn[0]) {
case 0x9c: /* pushfl */
*tos &= ~(TF_MASK | IF_MASK);
@@ -375,9 +375,9 @@ static void __kprobes resume_execution(s
case 0xcb:
case 0xc2:
case 0xca:
- regs->eflags &= ~TF_MASK;
- /* eip is already adjusted, no more changes required*/
- return;
+ case 0xea: /* jmp absolute -- eip is correct */
+ /* eip is already adjusted, no more changes required */
+ goto no_change;
case 0xe8: /* call relative - Fix return addr */
*tos = orig_eip + (*tos - copy_eip);
break;
@@ -385,27 +385,21 @@ static void __kprobes resume_execution(s
if ((p->ainsn.insn[1] & 0x30) == 0x10) {
/* call absolute, indirect */
/* Fix return addr; eip is correct. */
- next_eip = regs->eip;
*tos = orig_eip + (*tos - copy_eip);
+ goto no_change;
} else if (((p->ainsn.insn[1] & 0x31) == 0x20) || /* jmp near, absolute indirect */
((p->ainsn.insn[1] & 0x31) == 0x21)) { /* jmp far, absolute indirect */
/* eip is correct. */
- next_eip = regs->eip;
+ goto no_change;
}
- break;
- case 0xea: /* jmp absolute -- eip is correct */
- next_eip = regs->eip;
- break;
default:
break;
}
- regs->eflags &= ~TF_MASK;
- if (next_eip) {
- regs->eip = next_eip;
- } else {
- regs->eip = orig_eip + (regs->eip - copy_eip);
- }
+ regs->eip = orig_eip + (regs->eip - copy_eip);
+
+no_change:
+ return;
}
/*