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[PATCH] kprobe: fix resume execution on i386
- From: Masami Hiramatsu <hiramatu at sdl dot hitachi dot co dot jp>
- To: Andrew Morton <akpm at osdl dot org>, Ananth N Mavinakayanahalli <ananth at in dot ibm dot com>, "Keshavamurthy, Anil S" <anil dot s dot keshavamurthy at intel dot com>, Prasanna S Panchamukhi <prasanna at in dot ibm dot com>
- Cc: SystemTAP <systemtap at sources dot redhat dot com>, linux-kernel <linux-kernel at vger dot kernel dot org>, Jim Keniston <jkenisto at us dot ibm dot com>, Yumiko Sugita <sugita at sdl dot hitachi dot co dot jp>, Satoshi Oshima <soshima at redhat dot com>, Hideo Aoki <haoki at redhat dot com>
- Date: Wed, 26 Apr 2006 16:50:05 +0900
- Subject: [PATCH] kprobe: fix resume execution on i386
Hi, Andrew
Here is a patch to fix resume_execution() to handle
iret and absolute jump opcode correctly on i386.
This patch can be applied against 2.6.17-rc2.
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 | 14 +++++++++-----
1 files changed, 9 insertions(+), 5 deletions(-)
diff -Narup a/arch/i386/kernel/kprobes.c b/arch/i386/kernel/kprobes.c
--- a/arch/i386/kernel/kprobes.c 2006-04-21 12:23:45.000000000 +0900
+++ b/arch/i386/kernel/kprobes.c 2006-04-21 21:26:51.000000000 +0900
@@ -452,10 +452,11 @@ static void __kprobes resume_execution(s
*tos &= ~(TF_MASK | IF_MASK);
*tos |= kcb->kprobe_old_eflags;
break;
- case 0xc3: /* ret/lret */
- case 0xcb:
- case 0xc2:
+ case 0xc2: /* iret/ret/lret */
+ case 0xc3:
case 0xca:
+ case 0xcb:
+ case 0xcf:
case 0xea: /* jmp absolute -- eip is correct */
/* eip is already adjusted, no more changes required */
p->ainsn.boostable = 1;
@@ -463,10 +464,13 @@ static void __kprobes resume_execution(s
case 0xe8: /* call relative - Fix return addr */
*tos = orig_eip + (*tos - copy_eip);
break;
+ case 0x9a: /* call absolute -- same as call absolute, indirect */
+ *tos = orig_eip + (*tos - copy_eip);
+ goto no_change;
case 0xff:
if ((p->ainsn.insn[1] & 0x30) == 0x10) {
- /* call absolute, indirect */
- /*
+ /*
+ * call absolute, indirect
* Fix return addr; eip is correct.
* But this is not boostable
*/