---

yaml
---
r: 340301
b: refs/heads/master
c: 69b58a6
h: refs/heads/master
i:
  340299: 0685dda
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 999121a10cbf091cdb3c168754de6ddf1992e656
+refs/heads/master: 69b58a67213506f98835b0ee8cf24324f59a1442

trunk/arch/blackfin/Kconfig

@@ -45,8 +45,6 @@ config BLACKFIN
 	select ARCH_USES_GETTIMEOFFSET if !GENERIC_CLOCKEVENTS
 	select HAVE_MOD_ARCH_SPECIFIC
 	select MODULES_USE_ELF_RELA
-	select GENERIC_KERNEL_THREAD
-	select GENERIC_KERNEL_EXECVE
 
 config GENERIC_CSUM
 	def_bool y

trunk/arch/blackfin/include/asm/processor.h

@@ -75,6 +75,8 @@ static inline void release_thread(struct task_struct *dead_task)
 {
 }
 
+extern int kernel_thread(int (*fn) (void *), void *arg, unsigned long flags);
+
 /*
  * Free current thread data structures etc..
  */

trunk/arch/blackfin/include/asm/unistd.h

@@ -446,7 +446,6 @@
 #define __ARCH_WANT_SYS_NICE
 #define __ARCH_WANT_SYS_RT_SIGACTION
 #define __ARCH_WANT_SYS_RT_SIGSUSPEND
-#define __ARCH_WANT_SYS_EXECVE
 
 /*
  * "Conditional" syscalls

trunk/arch/blackfin/kernel/entry.S

@@ -46,16 +46,22 @@ ENTRY(_ret_from_fork)
 	SP += -12;
 	pseudo_long_call _schedule_tail, p5;
 	SP += 12;
-	p1 = [sp++];
-	r0 = [sp++];
-	cc = p1 == 0;
-	if cc jump .Lfork;
-	sp += -12;
-	call (p1);
-	sp += 12;
-.Lfork:
+	r0 = [sp + PT_IPEND];
+	cc = bittst(r0,1);
+	if cc jump .Lin_kernel;
 	RESTORE_CONTEXT
 	rti;
+.Lin_kernel:
+	bitclr(r0,1);
+	[sp + PT_IPEND] = r0;
+	/* do a 'fake' RTI by jumping to [RETI]
+	 * to avoid clearing supervisor mode in child
+	 */
+	r0 = [sp + PT_PC];
+	[sp + PT_P0] = r0;
+
+	RESTORE_ALL_SYS
+	jump (p0);
 ENDPROC(_ret_from_fork)
 
 ENTRY(_sys_vfork)

trunk/arch/blackfin/kernel/process.c

@@ -101,6 +101,40 @@ void cpu_idle(void)
 	}
 }
 
+/*
+ * This gets run with P1 containing the
+ * function to call, and R1 containing
+ * the "args".  Note P0 is clobbered on the way here.
+ */
+void kernel_thread_helper(void);
+__asm__(".section .text\n"
+	".align 4\n"
+	"_kernel_thread_helper:\n\t"
+	"\tsp += -12;\n\t"
+	"\tr0 = r1;\n\t" "\tcall (p1);\n\t" "\tcall _do_exit;\n" ".previous");
+
+/*
+ * Create a kernel thread.
+ */
+pid_t kernel_thread(int (*fn) (void *), void *arg, unsigned long flags)
+{
+	struct pt_regs regs;
+
+	memset(&regs, 0, sizeof(regs));
+
+	regs.r1 = (unsigned long)arg;
+	regs.p1 = (unsigned long)fn;
+	regs.pc = (unsigned long)kernel_thread_helper;
+	regs.orig_p0 = -1;
+	/* Set bit 2 to tell ret_from_fork we should be returning to kernel
+	   mode.  */
+	regs.ipend = 0x8002;
+	__asm__ __volatile__("%0 = syscfg;":"=da"(regs.syscfg):);
+	return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, &regs, 0, NULL,
+		       NULL);
+}
+EXPORT_SYMBOL(kernel_thread);
+
 /*
  * Do necessary setup to start up a newly executed thread.
  *
@@ -159,31 +193,38 @@ copy_thread(unsigned long clone_flags,
 	    struct task_struct *p, struct pt_regs *regs)
 {
 	struct pt_regs *childregs;
-	unsigned long *v;
 
 	childregs = (struct pt_regs *) (task_stack_page(p) + THREAD_SIZE) - 1;
-	v = ((unsigned long *)childregs) - 2;
-	if (unlikely(!regs)) {
-		memset(childregs, 0, sizeof(struct pt_regs));
-		v[0] = usp;
-		v[1] = topstk;
-		childregs->orig_p0 = -1;
-		childregs->ipend = 0x8000;
-		__asm__ __volatile__("%0 = syscfg;":"=da"(childregs->syscfg):);
-		p->thread.usp = 0;
-	} else {
-		*childregs = *regs;
-		childregs->r0 = 0;
-		p->thread.usp = usp;
-		v[0] = v[1] = 0;
-	}
+	*childregs = *regs;
+	childregs->r0 = 0;
 
-	p->thread.ksp = (unsigned long)v;
+	p->thread.usp = usp;
+	p->thread.ksp = (unsigned long)childregs;
 	p->thread.pc = (unsigned long)ret_from_fork;
 
 	return 0;
 }
 
+/*
+ * sys_execve() executes a new program.
+ */
+asmlinkage int sys_execve(const char __user *name,
+			  const char __user *const __user *argv,
+			  const char __user *const __user *envp)
+{
+	int error;
+	struct filename *filename;
+	struct pt_regs *regs = (struct pt_regs *)((&name) + 6);
+
+	filename = getname(name);
+	error = PTR_ERR(filename);
+	if (IS_ERR(filename))
+		return error;
+	error = do_execve(filename->name, argv, envp, regs);
+	putname(filename);
+	return error;
+}
+
 unsigned long get_wchan(struct task_struct *p)
 {
 	unsigned long fp, pc;

trunk/arch/blackfin/mach-common/entry.S

@@ -530,6 +530,61 @@ ENTRY(_trap) /* Exception: 4th entry into system event table(supervisor mode)*/
 	jump .Lsyscall_really_exit;
 ENDPROC(_trap)
 
+ENTRY(_kernel_execve)
+	link SIZEOF_PTREGS;
+	p0 = sp;
+	r3 = SIZEOF_PTREGS / 4;
+	r4 = 0(x);
+.Lclear_regs:
+	[p0++] = r4;
+	r3 += -1;
+	cc = r3 == 0;
+	if !cc jump .Lclear_regs (bp);
+
+	p0 = sp;
+	sp += -16;
+	[sp + 12] = p0;
+	pseudo_long_call _do_execve, p5;
+	SP += 16;
+	cc = r0 == 0;
+	if ! cc jump .Lexecve_failed;
+	/* Success.  Copy our temporary pt_regs to the top of the kernel
+	 * stack and do a normal exception return.
+	 */
+	r1 = sp;
+	r0 = (-KERNEL_STACK_SIZE) (x);
+	r1 = r1 & r0;
+	p2 = r1;
+	p3 = [p2];
+	r0 = KERNEL_STACK_SIZE - 4 (z);
+	p1 = r0;
+	p1 = p1 + p2;
+
+	p0 = fp;
+	r4 = [p0--];
+	r3 = SIZEOF_PTREGS / 4;
+.Lcopy_regs:
+	r4 = [p0--];
+	[p1--] = r4;
+	r3 += -1;
+	cc = r3 == 0;
+	if ! cc jump .Lcopy_regs (bp);
+
+	r0 = (KERNEL_STACK_SIZE - SIZEOF_PTREGS) (z);
+	p1 = r0;
+	p1 = p1 + p2;
+	sp = p1;
+	r0 = syscfg;
+	[SP + PT_SYSCFG] = r0;
+	[p3 + (TASK_THREAD + THREAD_KSP)] = sp;
+
+	RESTORE_CONTEXT;
+	rti;
+.Lexecve_failed:
+	unlink;
+	rts;
+ENDPROC(_kernel_execve)
+
 ENTRY(_system_call)
 	/* Store IPEND */
 	p2.l = lo(IPEND);

trunk/arch/cris/Kconfig

@@ -49,6 +49,7 @@ config CRIS
 	select GENERIC_SMP_IDLE_THREAD if ETRAX_ARCH_V32
 	select GENERIC_CMOS_UPDATE
 	select MODULES_USE_ELF_RELA
+	select GENERIC_KERNEL_THREAD
 
 config HZ
 	int

trunk/arch/cris/arch-v10/kernel/entry.S

@@ -35,6 +35,7 @@
 	.globl system_call
 	.globl ret_from_intr
 	.globl ret_from_fork
+	.globl ret_from_kernel_thread
 	.globl resume
 	.globl multiple_interrupt
 	.globl hwbreakpoint
@@ -81,7 +82,14 @@ ret_from_fork:
 	jsr schedule_tail
 	ba  ret_from_sys_call
 	nop
-
+
+ret_from_kernel_thread:
+	jsr schedule_tail
+	move.d	$r2, $r10	; argument is here
+	jsr	$r1		; call the payload
+	moveq	0, $r10
+	jsr	sys_exit	; never returns
+
 ret_from_intr:
 	;; check for resched if preemptive kernel or if we're going back to user-mode 
 	;; this test matches the user_regs(regs) macro

trunk/arch/cris/arch-v10/kernel/process.c

@@ -17,6 +17,7 @@
 #include <arch/svinto.h>
 #include <linux/init.h>
 #include <arch/system.h>
+#include <asm/ptrace.h>
 
 #ifdef CONFIG_ETRAX_GPIO
 void etrax_gpio_wake_up_check(void); /* drivers/gpio.c */
@@ -81,31 +82,6 @@ unsigned long thread_saved_pc(struct task_struct *t)
 	return task_pt_regs(t)->irp;
 }
 
-static void kernel_thread_helper(void* dummy, int (*fn)(void *), void * arg)
-{
-  fn(arg);
-  do_exit(-1); /* Should never be called, return bad exit value */
-}
-
-/*
- * Create a kernel thread
- */
-int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
-{
-	struct pt_regs regs;
-
-	memset(&regs, 0, sizeof(regs));
-
-        /* Don't use r10 since that is set to 0 in copy_thread */
-	regs.r11 = (unsigned long)fn;
-	regs.r12 = (unsigned long)arg;
-	regs.irp = (unsigned long)kernel_thread_helper;
-	regs.dccr = 1 << I_DCCR_BITNR;
-
-	/* Ok, create the new process.. */
-        return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
-}
-
 /* setup the child's kernel stack with a pt_regs and switch_stack on it.
  * it will be un-nested during _resume and _ret_from_sys_call when the
  * new thread is scheduled.
@@ -115,29 +91,35 @@ int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
  *
  */
 asmlinkage void ret_from_fork(void);
+asmlinkage void ret_from_kernel_thread(void);
 
 int copy_thread(unsigned long clone_flags, unsigned long usp,
-		unsigned long unused,
+		unsigned long arg,
 		struct task_struct *p, struct pt_regs *regs)
 {
-	struct pt_regs * childregs;
-	struct switch_stack *swstack;
+	struct pt_regs *childregs = task_pt_regs(p);
+	struct switch_stack *swstack = ((struct switch_stack *)childregs) - 1;
 
 	/* put the pt_regs structure at the end of the new kernel stack page and fix it up
 	 * remember that the task_struct doubles as the kernel stack for the task
 	 */
 
-	childregs = task_pt_regs(p);
-
+	if (unlikely(p->flags & PF_KTHREAD)) {
+		memset(swstack, 0,
+			sizeof(struct switch_stack) + sizeof(struct pt_regs));
+		swstack->r1 = usp;
+		swstack->r2 = arg;
+		childregs->dccr = 1 << I_DCCR_BITNR;
+		swstack->return_ip = (unsigned long) ret_from_kernel_thread;
+		p->thread.ksp = (unsigned long) swstack;
+		p->thread.usp = 0;
+		return 0;
+	}
 	*childregs = *regs;  /* struct copy of pt_regs */
-
-        p->set_child_tid = p->clear_child_tid = NULL;
 
         childregs->r10 = 0;  /* child returns 0 after a fork/clone */
-
-	/* put the switch stack right below the pt_regs */
 
-	swstack = ((struct switch_stack *)childregs) - 1;
+	/* put the switch stack right below the pt_regs */
 
 	swstack->r9 = 0; /* parameter to ret_from_sys_call, 0 == dont restart the syscall */
 
@@ -147,7 +129,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 
 	/* fix the user-mode stackpointer */
 
-	p->thread.usp = usp;	
+	p->thread.usp = usp;
 
 	/* and the kernel-mode one */
 
@@ -161,45 +143,28 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 	return 0;
 }
 
-/* 
- * Be aware of the "magic" 7th argument in the four system-calls below.
- * They need the latest stackframe, which is put as the 7th argument by
- * entry.S. The previous arguments are dummies or actually used, but need
- * to be defined to reach the 7th argument.
- *
- * N.B.: Another method to get the stackframe is to use current_regs(). But
- * it returns the latest stack-frame stacked when going from _user mode_ and
- * some of these (at least sys_clone) are called from kernel-mode sometimes
- * (for example during kernel_thread, above) and thus cannot use it. Thus,
- * to be sure not to get any surprises, we use the method for the other calls
- * as well.
- */
-
-asmlinkage int sys_fork(long r10, long r11, long r12, long r13, long mof, long srp,
-			struct pt_regs *regs)
+asmlinkage int sys_fork(void)
 {
-	return do_fork(SIGCHLD, rdusp(), regs, 0, NULL, NULL);
+	return do_fork(SIGCHLD, rdusp(), current_pt_regs(), 0, NULL, NULL);
 }
 
 /* if newusp is 0, we just grab the old usp */
 /* FIXME: Is parent_tid/child_tid really third/fourth argument? Update lib? */
 asmlinkage int sys_clone(unsigned long newusp, unsigned long flags,
-			 int* parent_tid, int* child_tid, long mof, long srp,
-			 struct pt_regs *regs)
+			 int* parent_tid, int* child_tid)
 {
 	if (!newusp)
 		newusp = rdusp();
-	return do_fork(flags, newusp, regs, 0, parent_tid, child_tid);
+	return do_fork(flags, newusp, current_pt_regs(), 0, parent_tid, child_tid);
 }
 
 /* vfork is a system call in i386 because of register-pressure - maybe
  * we can remove it and handle it in libc but we put it here until then.
  */
 
-asmlinkage int sys_vfork(long r10, long r11, long r12, long r13, long mof, long srp,
-			 struct pt_regs *regs)
+asmlinkage int sys_vfork(void)
 {
-        return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, rdusp(), regs, 0, NULL, NULL);
+        return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, rdusp(), current_pt_regs(), 0, NULL, NULL);
 }
 
 /*