[PATCH] i386: Add kernel thread stack frame termination for properly stopping stack unwinds.

One open question: Should this added push perhaps be made conditional
upon CONFIG_STACK_UNWIND or CONFIG_UNWIND_INFO?
[AK: not needed, these are all very slow paths]

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 4 insertions, 10 deletions

diff --git a/arch/i386/kernel/head.S b/arch/i386/kernel/head.S
index eb79aa2fa8bb..a6b8bd89aa27 100644
--- a/arch/i386/kernel/head.S
+++ b/arch/i386/kernel/head.S
@@ -317,20 +317,14 @@ is386:	movl $2,%ecx		# set MP
         movl %eax,%gs
         lldt %ax
         cld                     # gcc2 wants the direction flag cleared at all times
+        pushl %eax              # fake return address
 #ifdef CONFIG_SMP
         movb ready, %cl
         movb $1, ready
-        cmpb $0,%cl
-        je 1f                   # the first CPU calls start_kernel
-                                # all other CPUs call initialize_secondary
-        call initialize_secondary
-        jmp L6
-1:
+        cmpb $0,%cl             # the first CPU calls start_kernel
+        jne initialize_secondary # all other CPUs call initialize_secondary
 #endif /* CONFIG_SMP */
-        call start_kernel
-L6:
-        jmp L6                  # main should never return here, but
-                                # just in case, we know what happens.
+        jmp start_kernel
 
 /*
  * We depend on ET to be correct. This checks for 287/387.