diff options
Diffstat (limited to 'arch/x86/kernel/process_32.c')
| -rw-r--r-- | arch/x86/kernel/process_32.c | 37 |
1 files changed, 30 insertions, 7 deletions
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index b9ff83c7135b..44e0bff38e72 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -57,6 +57,7 @@ #include <asm/switch_to.h> asmlinkage void ret_from_fork(void) __asm__("ret_from_fork"); +asmlinkage void ret_from_kernel_thread(void) __asm__("ret_from_kernel_thread"); /* * Return saved PC of a blocked thread. @@ -127,23 +128,39 @@ void release_thread(struct task_struct *dead_task) } int copy_thread(unsigned long clone_flags, unsigned long sp, - unsigned long unused, + unsigned long arg, struct task_struct *p, struct pt_regs *regs) { - struct pt_regs *childregs; + struct pt_regs *childregs = task_pt_regs(p); struct task_struct *tsk; int err; - childregs = task_pt_regs(p); + p->thread.sp = (unsigned long) childregs; + p->thread.sp0 = (unsigned long) (childregs+1); + + if (unlikely(!regs)) { + /* kernel thread */ + memset(childregs, 0, sizeof(struct pt_regs)); + p->thread.ip = (unsigned long) ret_from_kernel_thread; + task_user_gs(p) = __KERNEL_STACK_CANARY; + childregs->ds = __USER_DS; + childregs->es = __USER_DS; + childregs->fs = __KERNEL_PERCPU; + childregs->bx = sp; /* function */ + childregs->bp = arg; + childregs->orig_ax = -1; + childregs->cs = __KERNEL_CS | get_kernel_rpl(); + childregs->flags = X86_EFLAGS_IF | X86_EFLAGS_BIT1; + p->fpu_counter = 0; + p->thread.io_bitmap_ptr = NULL; + memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps)); + return 0; + } *childregs = *regs; childregs->ax = 0; childregs->sp = sp; - p->thread.sp = (unsigned long) childregs; - p->thread.sp0 = (unsigned long) (childregs+1); - p->thread.ip = (unsigned long) ret_from_fork; - task_user_gs(p) = get_user_gs(regs); p->fpu_counter = 0; @@ -190,6 +207,12 @@ start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp) regs->cs = __USER_CS; regs->ip = new_ip; regs->sp = new_sp; + regs->flags = X86_EFLAGS_IF; + /* + * force it to the iret return path by making it look as if there was + * some work pending. + */ + set_thread_flag(TIF_NOTIFY_RESUME); } EXPORT_SYMBOL_GPL(start_thread); |