powerpc: put the "zero usp means using parent's stack pointer" to copy_thread()
simplifies callers, at that...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index de9f032..3665d28 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -761,7 +761,8 @@
} else {
CHECK_FULL_REGS(regs);
*childregs = *regs;
- childregs->gpr[1] = usp;
+ if (usp)
+ childregs->gpr[1] = usp;
p->thread.regs = childregs;
childregs->gpr[3] = 0; /* Result from fork() */
if (clone_flags & CLONE_SETTLS) {
@@ -1030,8 +1031,6 @@
int __user *child_tidp, int p6,
struct pt_regs *regs)
{
- if (usp == 0)
- usp = regs->gpr[1]; /* stack pointer for child */
return do_fork(clone_flags, usp, regs, 0, parent_tidp, child_tidp);
}
@@ -1039,14 +1038,14 @@
unsigned long p4, unsigned long p5, unsigned long p6,
struct pt_regs *regs)
{
- return do_fork(SIGCHLD, regs->gpr[1], regs, 0, NULL, NULL);
+ return do_fork(SIGCHLD, 0, regs, 0, NULL, NULL);
}
int sys_vfork(unsigned long p1, unsigned long p2, unsigned long p3,
unsigned long p4, unsigned long p5, unsigned long p6,
struct pt_regs *regs)
{
- return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->gpr[1],
+ return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, 0,
regs, 0, NULL, NULL);
}