Messages in this thread Patch in this message | | | Date | Mon, 30 Jan 2006 21:44:49 +0900 | From | Masami Hiramatsu <> | Subject | [PATCH][1/2] kprobe: kprobe-booster against 2.6.16-rc1 for i386 |
| |
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: hiramatu@sdl.hitachi.co.jp
Signed-off-by: Masami Hiramatsu <hiramatu@sdl.hitachi.co.jp>
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; }
/*
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |