Merge branch 'x86/asm' into x86/urgent

Merge reason: it's stable so lets push it upstream.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

9 files changed, 138 insertions, 211 deletions

diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index 50b9c220e121..44a8e0dc6737 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -725,22 +725,61 @@ END(syscall_badsys)
 /*
  * System calls that need a pt_regs pointer.
  */
-#define PTREGSCALL(name) \
+#define PTREGSCALL0(name) \
 	ALIGN; \
 ptregs_##name: \
 	leal 4(%esp),%eax; \
 	jmp sys_##name;
 
-PTREGSCALL(iopl)
-PTREGSCALL(fork)
-PTREGSCALL(clone)
-PTREGSCALL(vfork)
-PTREGSCALL(execve)
-PTREGSCALL(sigaltstack)
-PTREGSCALL(sigreturn)
-PTREGSCALL(rt_sigreturn)
-PTREGSCALL(vm86)
-PTREGSCALL(vm86old)
+#define PTREGSCALL1(name) \
+	ALIGN; \
+ptregs_##name: \
+	leal 4(%esp),%edx; \
+	movl (PT_EBX+4)(%esp),%eax; \
+	jmp sys_##name;
+
+#define PTREGSCALL2(name) \
+	ALIGN; \
+ptregs_##name: \
+	leal 4(%esp),%ecx; \
+	movl (PT_ECX+4)(%esp),%edx; \
+	movl (PT_EBX+4)(%esp),%eax; \
+	jmp sys_##name;
+
+#define PTREGSCALL3(name) \
+	ALIGN; \
+ptregs_##name: \
+	leal 4(%esp),%eax; \
+	pushl %eax; \
+	movl PT_EDX(%eax),%ecx; \
+	movl PT_ECX(%eax),%edx; \
+	movl PT_EBX(%eax),%eax; \
+	call sys_##name; \
+	addl $4,%esp; \
+	ret
+
+PTREGSCALL1(iopl)
+PTREGSCALL0(fork)
+PTREGSCALL0(vfork)
+PTREGSCALL3(execve)
+PTREGSCALL2(sigaltstack)
+PTREGSCALL0(sigreturn)
+PTREGSCALL0(rt_sigreturn)
+PTREGSCALL2(vm86)
+PTREGSCALL1(vm86old)
+
+/* Clone is an oddball.  The 4th arg is in %edi */
+	ALIGN;
+ptregs_clone:
+	leal 4(%esp),%eax
+	pushl %eax
+	pushl PT_EDI(%eax)
+	movl PT_EDX(%eax),%ecx
+	movl PT_ECX(%eax),%edx
+	movl PT_EBX(%eax),%eax
+	call sys_clone
+	addl $8,%esp
+	ret
 
 .macro FIXUP_ESPFIX_STACK
 /*
@@ -1008,12 +1047,8 @@ END(spurious_interrupt_bug)
 ENTRY(kernel_thread_helper)
 	pushl $0		# fake return address for unwinder
 	CFI_STARTPROC
-	movl %edx,%eax
-	push %edx
-	CFI_ADJUST_CFA_OFFSET 4
-	call *%ebx
-	push %eax
-	CFI_ADJUST_CFA_OFFSET 4
+	movl %edi,%eax
+	call *%esi
 	call do_exit
 	ud2			# padding for call trace
 	CFI_ENDPROC
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 63bca794c8f9..73d9b2c0e217 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -1166,63 +1166,20 @@ bad_gs:
 	jmp  2b
 	.previous
 
-/*
- * Create a kernel thread.
- *
- * C extern interface:
- *	extern long kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
- *
- * asm input arguments:
- *	rdi: fn, rsi: arg, rdx: flags
- */
-ENTRY(kernel_thread)
-	CFI_STARTPROC
-	FAKE_STACK_FRAME $child_rip
-	SAVE_ALL
-
-	# rdi: flags, rsi: usp, rdx: will be &pt_regs
-	movq %rdx,%rdi
-	orq  kernel_thread_flags(%rip),%rdi
-	movq $-1, %rsi
-	movq %rsp, %rdx
-
-	xorl %r8d,%r8d
-	xorl %r9d,%r9d
-
-	# clone now
-	call do_fork
-	movq %rax,RAX(%rsp)
-	xorl %edi,%edi
-
-	/*
-	 * It isn't worth to check for reschedule here,
-	 * so internally to the x86_64 port you can rely on kernel_thread()
-	 * not to reschedule the child before returning, this avoids the need
-	 * of hacks for example to fork off the per-CPU idle tasks.
-	 * [Hopefully no generic code relies on the reschedule -AK]
-	 */
-	RESTORE_ALL
-	UNFAKE_STACK_FRAME
-	ret
-	CFI_ENDPROC
-END(kernel_thread)
-
-ENTRY(child_rip)
+ENTRY(kernel_thread_helper)
 	pushq $0		# fake return address
 	CFI_STARTPROC
 	/*
 	 * Here we are in the child and the registers are set as they were
 	 * at kernel_thread() invocation in the parent.
 	 */
-	movq %rdi, %rax
-	movq %rsi, %rdi
-	call *%rax
+	call *%rsi
 	# exit
 	mov %eax, %edi
 	call do_exit
 	ud2			# padding for call trace
 	CFI_ENDPROC
-END(child_rip)
+END(kernel_thread_helper)
 
 /*
  * execve(). This function needs to use IRET, not SYSRET, to set up all state properly.
diff --git a/arch/x86/kernel/ioport.c b/arch/x86/kernel/ioport.c
index 99c4d308f16b..8eec0ec59af2 100644
--- a/arch/x86/kernel/ioport.c
+++ b/arch/x86/kernel/ioport.c
@@ -103,9 +103,10 @@ asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int turn_on)
  * on system-call entry - see also fork() and the signal handling
  * code.
  */
-static int do_iopl(unsigned int level, struct pt_regs *regs)
+long sys_iopl(unsigned int level, struct pt_regs *regs)
 {
 	unsigned int old = (regs->flags >> 12) & 3;
+	struct thread_struct *t = &current->thread;
 
 	if (level > 3)
 		return -EINVAL;
@@ -115,29 +116,8 @@ static int do_iopl(unsigned int level, struct pt_regs *regs)
 			return -EPERM;
 	}
 	regs->flags = (regs->flags & ~X86_EFLAGS_IOPL) | (level << 12);
-
-	return 0;
-}
-
-#ifdef CONFIG_X86_32
-long sys_iopl(struct pt_regs *regs)
-{
-	unsigned int level = regs->bx;
-	struct thread_struct *t = &current->thread;
-	int rc;
-
-	rc = do_iopl(level, regs);
-	if (rc < 0)
-		goto out;
-
 	t->iopl = level << 12;
 	set_iopl_mask(t->iopl);
-out:
-	return rc;
-}
-#else
-asmlinkage long sys_iopl(unsigned int level, struct pt_regs *regs)
-{
-	return do_iopl(level, regs);
+
+	return 0;
 }
-#endif
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 7a7bd4e3ec49..98c2cdeb599e 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -255,6 +255,76 @@ int sys_vfork(struct pt_regs *regs)
 		       NULL, NULL);
 }
 
+long
+sys_clone(unsigned long clone_flags, unsigned long newsp,
+	  void __user *parent_tid, void __user *child_tid, struct pt_regs *regs)
+{
+	if (!newsp)
+		newsp = regs->sp;
+	return do_fork(clone_flags, newsp, regs, 0, parent_tid, child_tid);
+}
+
+/*
+ * This gets run with %si containing the
+ * function to call, and %di containing
+ * the "args".
+ */
+extern void kernel_thread_helper(void);
+
+/*
+ * Create a kernel thread
+ */
+int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
+{
+	struct pt_regs regs;
+
+	memset(&regs, 0, sizeof(regs));
+
+	regs.si = (unsigned long) fn;
+	regs.di = (unsigned long) arg;
+
+#ifdef CONFIG_X86_32
+	regs.ds = __USER_DS;
+	regs.es = __USER_DS;
+	regs.fs = __KERNEL_PERCPU;
+	regs.gs = __KERNEL_STACK_CANARY;
+#endif
+
+	regs.orig_ax = -1;
+	regs.ip = (unsigned long) kernel_thread_helper;
+	regs.cs = __KERNEL_CS | get_kernel_rpl();
+	regs.flags = X86_EFLAGS_IF | 0x2;
+
+	/* Ok, create the new process.. */
+	return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
+}
+EXPORT_SYMBOL(kernel_thread);
+
+/*
+ * sys_execve() executes a new program.
+ */
+long sys_execve(char __user *name, char __user * __user *argv,
+		char __user * __user *envp, struct pt_regs *regs)
+{
+	long error;
+	char *filename;
+
+	filename = getname(name);
+	error = PTR_ERR(filename);
+	if (IS_ERR(filename))
+		return error;
+	error = do_execve(filename, argv, envp, regs);
+
+#ifdef CONFIG_X86_32
+	if (error == 0) {
+		/* Make sure we don't return using sysenter.. */
+                set_thread_flag(TIF_IRET);
+        }
+#endif
+
+	putname(filename);
+	return error;
+}
 
 /*
  * Idle related variables and functions
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index 120b88797a75..9c517b5858f0 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -180,39 +180,6 @@ void show_regs(struct pt_regs *regs)
 	show_trace(NULL, regs, &regs->sp, regs->bp);
 }
 
-/*
- * This gets run with %bx containing the
- * function to call, and %dx containing
- * the "args".
- */
-extern void kernel_thread_helper(void);
-
-/*
- * Create a kernel thread
- */
-int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
-{
-	struct pt_regs regs;
-
-	memset(&regs, 0, sizeof(regs));
-
-	regs.bx = (unsigned long) fn;
-	regs.dx = (unsigned long) arg;
-
-	regs.ds = __USER_DS;
-	regs.es = __USER_DS;
-	regs.fs = __KERNEL_PERCPU;
-	regs.gs = __KERNEL_STACK_CANARY;
-	regs.orig_ax = -1;
-	regs.ip = (unsigned long) kernel_thread_helper;
-	regs.cs = __KERNEL_CS | get_kernel_rpl();
-	regs.flags = X86_EFLAGS_IF | X86_EFLAGS_SF | X86_EFLAGS_PF | 0x2;
-
-	/* Ok, create the new process.. */
-	return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
-}
-EXPORT_SYMBOL(kernel_thread);
-
 void release_thread(struct task_struct *dead_task)
 {
 	BUG_ON(dead_task->mm);
@@ -424,46 +391,6 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 	return prev_p;
 }
 
-int sys_clone(struct pt_regs *regs)
-{
-	unsigned long clone_flags;
-	unsigned long newsp;
-	int __user *parent_tidptr, *child_tidptr;
-
-	clone_flags = regs->bx;
-	newsp = regs->cx;
-	parent_tidptr = (int __user *)regs->dx;
-	child_tidptr = (int __user *)regs->di;
-	if (!newsp)
-		newsp = regs->sp;
-	return do_fork(clone_flags, newsp, regs, 0, parent_tidptr, child_tidptr);
-}
-
-/*
- * sys_execve() executes a new program.
- */
-int sys_execve(struct pt_regs *regs)
-{
-	int error;
-	char *filename;
-
-	filename = getname((char __user *) regs->bx);
-	error = PTR_ERR(filename);
-	if (IS_ERR(filename))
-		goto out;
-	error = do_execve(filename,
-			(char __user * __user *) regs->cx,
-			(char __user * __user *) regs->dx,
-			regs);
-	if (error == 0) {
-		/* Make sure we don't return using sysenter.. */
-		set_thread_flag(TIF_IRET);
-	}
-	putname(filename);
-out:
-	return error;
-}
-
 #define top_esp                (THREAD_SIZE - sizeof(unsigned long))
 #define top_ebp                (THREAD_SIZE - 2*sizeof(unsigned long))
 
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index e5ab0cd0ef36..52fbd0c60198 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -57,8 +57,6 @@ asmlinkage extern void ret_from_fork(void);
 DEFINE_PER_CPU(unsigned long, old_rsp);
 static DEFINE_PER_CPU(unsigned char, is_idle);
 
-unsigned long kernel_thread_flags = CLONE_VM | CLONE_UNTRACED;
-
 static ATOMIC_NOTIFIER_HEAD(idle_notifier);
 
 void idle_notifier_register(struct notifier_block *n)
@@ -273,8 +271,9 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
 	*childregs = *regs;
 
 	childregs->ax = 0;
-	childregs->sp = sp;
-	if (sp == ~0UL)
+	if (user_mode(regs))
+		childregs->sp = sp;
+	else
 		childregs->sp = (unsigned long)childregs;
 
 	p->thread.sp = (unsigned long) childregs;
@@ -508,25 +507,6 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 	return prev_p;
 }
 
-/*
- * sys_execve() executes a new program.
- */
-asmlinkage
-long sys_execve(char __user *name, char __user * __user *argv,
-		char __user * __user *envp, struct pt_regs *regs)
-{
-	long error;
-	char *filename;
-
-	filename = getname(name);
-	error = PTR_ERR(filename);
-	if (IS_ERR(filename))
-		return error;
-	error = do_execve(filename, argv, envp, regs);
-	putname(filename);
-	return error;
-}
-
 void set_personality_64bit(void)
 {
 	/* inherit personality from parent */
@@ -541,15 +521,6 @@ void set_personality_64bit(void)
 	current->personality &= ~READ_IMPLIES_EXEC;
 }
 
-asmlinkage long
-sys_clone(unsigned long clone_flags, unsigned long newsp,
-	  void __user *parent_tid, void __user *child_tid, struct pt_regs *regs)
-{
-	if (!newsp)
-		newsp = regs->sp;
-	return do_fork(clone_flags, newsp, regs, 0, parent_tid, child_tid);
-}
-
 unsigned long get_wchan(struct task_struct *p)
 {
 	unsigned long stack;
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index 74fe6d86dc5d..4fd173cd8e57 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -545,22 +545,12 @@ sys_sigaction(int sig, const struct old_sigaction __user *act,
 }
 #endif /* CONFIG_X86_32 */
 
-#ifdef CONFIG_X86_32
-int sys_sigaltstack(struct pt_regs *regs)
-{
-	const stack_t __user *uss = (const stack_t __user *)regs->bx;
-	stack_t __user *uoss = (stack_t __user *)regs->cx;
-
-	return do_sigaltstack(uss, uoss, regs->sp);
-}
-#else /* !CONFIG_X86_32 */
-asmlinkage long
+long
 sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
 		struct pt_regs *regs)
 {
 	return do_sigaltstack(uss, uoss, regs->sp);
 }
-#endif /* CONFIG_X86_32 */
 
 /*
  * Do a signal return; undo the signal stack.
diff --git a/arch/x86/kernel/vm86_32.c b/arch/x86/kernel/vm86_32.c
index 9c4e62539058..5ffb5622f793 100644
--- a/arch/x86/kernel/vm86_32.c
+++ b/arch/x86/kernel/vm86_32.c
@@ -197,9 +197,8 @@ out:
 static int do_vm86_irq_handling(int subfunction, int irqnumber);
 static void do_sys_vm86(struct kernel_vm86_struct *info, struct task_struct *tsk);
 
-int sys_vm86old(struct pt_regs *regs)
+int sys_vm86old(struct vm86_struct __user *v86, struct pt_regs *regs)
 {
-	struct vm86_struct __user *v86 = (struct vm86_struct __user *)regs->bx;
 	struct kernel_vm86_struct info; /* declare this _on top_,
 					 * this avoids wasting of stack space.
 					 * This remains on the stack until we
@@ -227,7 +226,7 @@ out:
 }
 
 
-int sys_vm86(struct pt_regs *regs)
+int sys_vm86(unsigned long cmd, unsigned long arg, struct pt_regs *regs)
 {
 	struct kernel_vm86_struct info; /* declare this _on top_,
 					 * this avoids wasting of stack space.
@@ -239,12 +238,12 @@ int sys_vm86(struct pt_regs *regs)
 	struct vm86plus_struct __user *v86;
 
 	tsk = current;
-	switch (regs->bx) {
+	switch (cmd) {
 	case VM86_REQUEST_IRQ:
 	case VM86_FREE_IRQ:
 	case VM86_GET_IRQ_BITS:
 	case VM86_GET_AND_RESET_IRQ:
-		ret = do_vm86_irq_handling(regs->bx, (int)regs->cx);
+		ret = do_vm86_irq_handling(cmd, (int)arg);
 		goto out;
 	case VM86_PLUS_INSTALL_CHECK:
 		/*
@@ -261,7 +260,7 @@ int sys_vm86(struct pt_regs *regs)
 	ret = -EPERM;
 	if (tsk->thread.saved_sp0)
 		goto out;
-	v86 = (struct vm86plus_struct __user *)regs->cx;
+	v86 = (struct vm86plus_struct __user *)arg;
 	tmp = copy_vm86_regs_from_user(&info.regs, &v86->regs,
 				       offsetof(struct kernel_vm86_struct, regs32) -
 				       sizeof(info.regs));
diff --git a/arch/x86/kernel/x8664_ksyms_64.c b/arch/x86/kernel/x8664_ksyms_64.c
index a1029769b6f2..9fafaf83b3b8 100644
--- a/arch/x86/kernel/x8664_ksyms_64.c
+++ b/arch/x86/kernel/x8664_ksyms_64.c
@@ -17,8 +17,6 @@
 EXPORT_SYMBOL(mcount);
 #endif
 
-EXPORT_SYMBOL(kernel_thread);
-
 EXPORT_SYMBOL(__get_user_1);
 EXPORT_SYMBOL(__get_user_2);
 EXPORT_SYMBOL(__get_user_4);