From 71949435d21159c82f57fa6729ac854f18160886 Mon Sep 17 00:00:00 2001
From: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Date: Wed, 8 Nov 2006 17:44:49 -0800
Subject: [PATCH] --- yaml --- r: 40829 b: refs/heads/master c:
 8bdc052eccdc7893d075d3f1f7103594a458c8c4 h: refs/heads/master i:   40827:
 6fe5cc29306fd9185726b714e35e28dd6b878100 v: v3

---
 [refs]                           |  2 +-
 trunk/arch/i386/kernel/kprobes.c | 22 +++++++++++++++-------
 2 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/[refs] b/[refs]
index 88d7ebd1c3bb..8f89bb57f6b0 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 4b438a23fb05b6566393f9f0a3987ea3dcc1c0c4
+refs/heads/master: 8bdc052eccdc7893d075d3f1f7103594a458c8c4
diff --git a/trunk/arch/i386/kernel/kprobes.c b/trunk/arch/i386/kernel/kprobes.c
index d98e44b16fe2..fc79e1e859c4 100644
--- a/trunk/arch/i386/kernel/kprobes.c
+++ b/trunk/arch/i386/kernel/kprobes.c
@@ -361,8 +361,11 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
 	asm volatile ( ".global kretprobe_trampoline\n"
 			"kretprobe_trampoline: \n"
 			"	pushf\n"
-			/* skip cs, eip, orig_eax, es, ds */
-			"	subl $20, %esp\n"
+			/* skip cs, eip, orig_eax */
+			"	subl $12, %esp\n"
+			"	pushl %gs\n"
+			"	pushl %ds\n"
+			"	pushl %es\n"
 			"	pushl %eax\n"
 			"	pushl %ebp\n"
 			"	pushl %edi\n"
@@ -373,10 +376,10 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
 			"	movl %esp, %eax\n"
 			"	call trampoline_handler\n"
 			/* move eflags to cs */
-			"	movl 48(%esp), %edx\n"
-			"	movl %edx, 44(%esp)\n"
+			"	movl 52(%esp), %edx\n"
+			"	movl %edx, 48(%esp)\n"
 			/* save true return address on eflags */
-			"	movl %eax, 48(%esp)\n"
+			"	movl %eax, 52(%esp)\n"
 			"	popl %ebx\n"
 			"	popl %ecx\n"
 			"	popl %edx\n"
@@ -384,8 +387,8 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
 			"	popl %edi\n"
 			"	popl %ebp\n"
 			"	popl %eax\n"
-			/* skip eip, orig_eax, es, ds */
-			"	addl $16, %esp\n"
+			/* skip eip, orig_eax, es, ds, gs */
+			"	addl $20, %esp\n"
 			"	popf\n"
 			"	ret\n");
 }
@@ -404,6 +407,10 @@ fastcall void *__kprobes trampoline_handler(struct pt_regs *regs)
 	INIT_HLIST_HEAD(&empty_rp);
 	spin_lock_irqsave(&kretprobe_lock, flags);
 	head = kretprobe_inst_table_head(current);
+	/* fixup registers */
+	regs->xcs = __KERNEL_CS;
+	regs->eip = trampoline_address;
+	regs->orig_eax = 0xffffffff;
 
 	/*
 	 * It is possible to have multiple instances associated with a given
@@ -425,6 +432,7 @@ fastcall void *__kprobes trampoline_handler(struct pt_regs *regs)
 
 		if (ri->rp && ri->rp->handler){
 			__get_cpu_var(current_kprobe) = &ri->rp->kp;
+			get_kprobe_ctlblk()->kprobe_status = KPROBE_HIT_ACTIVE;
 			ri->rp->handler(ri, regs);
 			__get_cpu_var(current_kprobe) = NULL;
 		}