Commit-ID: e55848a4f8ee52465771983e144f0c3337776eda
Gitweb: http://git.kernel.org/tip/e55848a4f8ee52465771983e144f0c3337776eda
Author: Oleg Nesterov <oleg@xxxxxxxxxx>
AuthorDate: Mon, 31 Mar 2014 17:24:14 +0200
Committer: Oleg Nesterov <oleg@xxxxxxxxxx>
CommitDate: Thu, 17 Apr 2014 21:58:20 +0200
uprobes/x86: Conditionalize the usage of handle_riprel_insn()
arch_uprobe_analyze_insn() calls handle_riprel_insn() at the start,
but only "0xff" and "default" cases need the UPROBE_FIX_RIP_ logic.
Move the callsite into "default" case and change the "0xff" case to
fall-through.
We are going to add the various hooks to handle the rip-relative
jmp/call instructions (and more), we need this change to enforce the
fact that the new code can not conflict with is_riprel_insn() logic
which, after this change, can only be used by default_xol_ops.
Note: arch_uprobe_abort_xol() still calls handle_riprel_post_xol()
directly. This is fine unless another _xol_ops we may add later will
need to reuse "UPROBE_FIX_RIP_AX|UPROBE_FIX_RIP_CX" bits in ->fixup.
In this case we can add uprobe_xol_ops->abort() hook, which (perhaps)
we will need anyway in the long term.
Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>
Reviewed-by: Jim Keniston <jkenisto@xxxxxxxxxx>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>
---
arch/x86/kernel/uprobes.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/arch/x86/kernel/uprobes.c b/arch/x86/kernel/uprobes.c
index 13ad8a3..08cdb82 100644
--- a/arch/x86/kernel/uprobes.c
+++ b/arch/x86/kernel/uprobes.c
@@ -482,8 +482,6 @@ int arch_uprobe_analyze_insn(struct arch_uprobe *auprobe, struct mm_struct *mm,
* and annotate arch_uprobe->fixups accordingly. To start with, ->fixups
* is either zero or it reflects rip-related fixups.
*/
- handle_riprel_insn(auprobe, &insn);
-
switch (OPCODE1(&insn)) {
case 0x9d: /* popf */
auprobe->fixups |= UPROBE_FIX_SETF;
@@ -512,9 +510,9 @@ int arch_uprobe_analyze_insn(struct arch_uprobe *auprobe, struct mm_struct *mm,
case 4: case 5: /* jmp or ljmp, indirect */
fix_ip = false;
}
- break;
+ /* fall through */
default:
- break;
+ handle_riprel_insn(auprobe, &insn);
}
if (fix_ip)
--
To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
|