[PATCH] x86: Revert new unwind kernel stack termination

Jan convinced me that it was unnecessary because the assembly stubs do
this already on the stack.

Cc: jbeulich@novell.com

Signed-off-by: Andi Kleen <ak@suse.de>

2 files changed, 1 insertions, 10 deletions

diff --git a/arch/i386/kernel/process.c b/arch/i386/kernel/process.c
index 57d375900afb..1e1fa3e391a3 100644
--- a/arch/i386/kernel/process.c
+++ b/arch/i386/kernel/process.c
@@ -336,7 +336,6 @@ extern void kernel_thread_helper(void);
 int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
 {
         struct pt_regs regs;
-        int err;
 
         memset(&regs, 0, sizeof(regs));
 
@@ -351,10 +350,7 @@ int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
         regs.eflags = X86_EFLAGS_IF | X86_EFLAGS_SF | X86_EFLAGS_PF | 0x2;
 
         /* Ok, create the new process.. */
-        err = do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
-        if (err == 0) /* terminate kernel stack */
-                task_pt_regs(current)->eip = 0;
-        return err;
+        return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
 }
 EXPORT_SYMBOL(kernel_thread);
 
diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S
index e3eddde3d3bb..7d401b00d822 100644
--- a/arch/x86_64/kernel/entry.S
+++ b/arch/x86_64/kernel/entry.S
@@ -980,11 +980,6 @@ ENTRY(kernel_thread)
         call do_fork
         movq %rax,RAX(%rsp)
         xorl %edi,%edi
-        test %rax,%rax
-        jnz  1f
-        /* terminate stack in child */
-        movq %rdi,RIP(%rsp)
-1:
 
         /*
          * It isn't worth to check for reschedule here,