From: mao, bibo <bibo.mao@intel.com>
Date: Fri, 28 Apr 2006 01:39:44 +0000 (-0700)
Subject: [PATCH] kprobe cleanup for VM_MASK judgement
X-Git-Tag: firefly_0821_release~35950
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=bf661987da6f5131475dfe3f51a98de4e2589ed3;p=firefly-linux-kernel-4.4.55.git

[PATCH] kprobe cleanup for VM_MASK judgement

When trap happens in user space, kprobe_exceptions_notify() funtion will
skip it.  This patch deletes some unnecessary code for VM_MASK judgement in
eflags.

Signed-off-by: bibo, mao <bibo.mao@intel.com>
Cc: Masami Hiramatsu <hiramatu@sdl.hitachi.co.jp>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Acked-by: "Keshavamurthy, Anil S" <anil.s.keshavamurthy@intel.com>
Acked-by: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Yumiko Sugita <sugita@sdl.hitachi.co.jp>
Cc: Satoshi Oshima <soshima@redhat.com>
Cc: Hideo Aoki <haoki@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

diff --git a/arch/i386/kernel/kprobes.c b/arch/i386/kernel/kprobes.c
index 043f5292e70a..6c93ddf09512 100644
--- a/arch/i386/kernel/kprobes.c
+++ b/arch/i386/kernel/kprobes.c
@@ -242,10 +242,6 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
 			kcb->kprobe_status = KPROBE_REENTER;
 			return 1;
 		} else {
-			if (regs->eflags & VM_MASK) {
-			/* We are in virtual-8086 mode. Return 0 */
-				goto no_kprobe;
-			}
 			if (*addr != BREAKPOINT_INSTRUCTION) {
 			/* The breakpoint instruction was removed by
 			 * another cpu right after we hit, no further
@@ -265,11 +261,6 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
 
 	p = get_kprobe(addr);
 	if (!p) {
-		if (regs->eflags & VM_MASK) {
-			/* We are in virtual-8086 mode. Return 0 */
-			goto no_kprobe;
-		}
-
 		if (*addr != BREAKPOINT_INSTRUCTION) {
 			/*
 			 * The breakpoint instruction was removed right