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-rw-r--r--arch/alpha/kernel/process.c39
1 files changed, 20 insertions, 19 deletions
diff --git a/arch/alpha/kernel/process.c b/arch/alpha/kernel/process.c
index 145473909199..6b33ecdbc534 100644
--- a/arch/alpha/kernel/process.c
+++ b/arch/alpha/kernel/process.c
@@ -259,33 +259,35 @@ alpha_vfork(struct pt_regs *regs)
/*
* Copy an alpha thread..
- *
- * Note the "stack_offset" stuff: when returning to kernel mode, we need
- * to have some extra stack-space for the kernel stack that still exists
- * after the "ret_from_fork". When returning to user mode, we only want
- * the space needed by the syscall stack frame (ie "struct pt_regs").
- * Use the passed "regs" pointer to determine how much space we need
- * for a kernel fork().
*/
int
copy_thread(unsigned long clone_flags, unsigned long usp,
- unsigned long unused,
+ unsigned long arg,
struct task_struct * p, struct pt_regs * regs)
{
extern void ret_from_fork(void);
+ extern void ret_from_kernel_thread(void);
struct thread_info *childti = task_thread_info(p);
- struct pt_regs * childregs;
- struct switch_stack * childstack, *stack;
- unsigned long stack_offset, settls;
-
- stack_offset = PAGE_SIZE - sizeof(struct pt_regs);
- if (!(regs->ps & 8))
- stack_offset = (PAGE_SIZE-1) & (unsigned long) regs;
- childregs = (struct pt_regs *)
- (stack_offset + PAGE_SIZE + task_stack_page(p));
-
+ struct pt_regs *childregs = task_pt_regs(p);
+ struct switch_stack *childstack, *stack;
+ unsigned long settls;
+
+ childstack = ((struct switch_stack *) childregs) - 1;
+ if (unlikely(!regs)) {
+ /* kernel thread */
+ memset(childstack, 0,
+ sizeof(struct switch_stack) + sizeof(struct pt_regs));
+ childstack->r26 = (unsigned long) ret_from_kernel_thread;
+ childstack->r9 = usp; /* function */
+ childstack->r10 = arg;
+ childregs->hae = alpha_mv.hae_cache,
+ childti->pcb.usp = 0;
+ childti->pcb.ksp = (unsigned long) childstack;
+ childti->pcb.flags = 1; /* set FEN, clear everything else */
+ return 0;
+ }
*childregs = *regs;
settls = regs->r20;
childregs->r0 = 0;
@@ -293,7 +295,6 @@ copy_thread(unsigned long clone_flags, unsigned long usp,
childregs->r20 = 1; /* OSF/1 has some strange fork() semantics. */
regs->r20 = 0;
stack = ((struct switch_stack *) regs) - 1;
- childstack = ((struct switch_stack *) childregs) - 1;
*childstack = *stack;
childstack->r26 = (unsigned long) ret_from_fork;
childti->pcb.usp = usp;