x86/process: Unify 32bit and 64bit implementations of get_wchan()

The stack layout and the functionality is identical. Use the 64bit
version for all of x86.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@alien8.de>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: kasan-dev <kasan-dev@googlegroups.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Wolfram Gloger <wmglo@dent.med.uni-muenchen.de>
Link: http://lkml.kernel.org/r/20150930083302.779694618@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 0 insertions, 28 deletions

diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index c13df2c735f8..737527b40e5b 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -324,31 +324,3 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 
 	return prev_p;
 }
-
-#define top_esp                (THREAD_SIZE - sizeof(unsigned long))
-#define top_ebp                (THREAD_SIZE - 2*sizeof(unsigned long))
-
-unsigned long get_wchan(struct task_struct *p)
-{
-	unsigned long bp, sp, ip;
-	unsigned long stack_page;
-	int count = 0;
-	if (!p || p == current || p->state == TASK_RUNNING)
-		return 0;
-	stack_page = (unsigned long)task_stack_page(p);
-	sp = p->thread.sp;
-	if (!stack_page || sp < stack_page || sp > top_esp+stack_page)
-		return 0;
-	/* include/asm-i386/system.h:switch_to() pushes bp last. */
-	bp = *(unsigned long *) sp;
-	do {
-		if (bp < stack_page || bp > top_ebp+stack_page)
-			return 0;
-		ip = *(unsigned long *) (bp+4);
-		if (!in_sched_functions(ip))
-			return ip;
-		bp = *(unsigned long *) bp;
-	} while (count++ < 16);
-	return 0;
-}
-