Stop mapping the u area at fixed UADDR in addition to its actual va.

While there, attempt to clean and comment stack usage in the kernel.
No functional change.

From the m88k SMP tree; help&test martin@

12 files changed, 92 insertions, 210 deletions

diff --git a/sys/arch/luna88k/luna88k/locore.S b/sys/arch/luna88k/luna88k/locore.S
index c4d9a9aebcf..b4da0dcc803 100644
--- a/sys/arch/luna88k/luna88k/locore.S
+++ b/sys/arch/luna88k/luna88k/locore.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: locore.S,v 1.7 2004/12/24 22:50:30 miod Exp $	*/
+/*	$OpenBSD: locore.S,v 1.8 2005/10/12 19:05:39 miod Exp $	*/
 /*
  * Copyright (c) 1998 Steve Murphree, Jr.
  * Copyright (c) 1996 Nivas Madhur
@@ -260,7 +260,6 @@ GLOBAL(start_text)
 ASLOCAL(master_start)
 	/*
 	 * Switch to interrupt stack
-	 * Use idle_u's stack instead?
 	 */
 	or.u	r31, r0,  hi16(_ASM_LABEL(intstack_end))
 	or	r31, r31, lo16(_ASM_LABEL(intstack_end))
@@ -311,34 +310,32 @@ ASLOCAL(master_start)
 	or.u	r2,  r0,  hi16(0x41000000)
 	st	r0,  r2,  lo16(0x41000000)
 
-	/* still on int stack */
+	/*
+	 * luna88k_bootstrap(), among other things, clears proc0's u area.
+	 * We are still using the interrupt stack here, thus we are not
+	 * affected...
+	 */
 	bsr	_C_LABEL(luna88k_bootstrap)
 
 	/*
-	 * we now know our cpu number, so we
-	 * can set interrupt_stack[cpu_number()] = intstack
+	 * ...and we can switch to the u area stack now.
 	 */
-	ldcr	r10, SR1
-	extu	r10, r10, FLAG_CPU_FIELD_WIDTH<0>	/* r10 <-- CPU# */
-
-	/* figure interrupt_stack[cpu_number()] */
-	or.u	r11,  r0, hi16(_C_LABEL(interrupt_stack))
-	or	r11, r11, lo16(_C_LABEL(interrupt_stack))
-	or.u	r12, r0,  hi16(_C_LABEL(intstack))
-	or	r12, r12, lo16(_C_LABEL(intstack))
-	st	r12, r11 [r10]
-
-	/* switch to proc0 uarea */
-	or.u	r10, r0, hi16(UADDR)
-	or	r31, r10,lo16(UADDR)
-	addu	r31, r31, USIZE - 8
-
-	/* make the call: main() */
-	or.u	r2, r0, hi16(UADDR)
-	or	r2, r2,lo16(UADDR)
-	bsr.n	_C_LABEL(main)
-	 addu	r2, r2, USIZE - 8
-	bsr	_C_LABEL(panic)
+	or.u	r10, r0,  hi16(_C_LABEL(curpcb))
+	ld	r31, r10, lo16(_C_LABEL(curpcb))
+	addu	r31, r31, USIZE
+
+	/* call main() - no arguments although main() still defines one */
+	bsr	_C_LABEL(main)
+	or.u	r2, r0, hi16(_ASM_LABEL(main_panic))
+	bsr.n	_C_LABEL(panic)
+	 or	r2, r2, lo16(_ASM_LABEL(main_panic))
+
+	data
+	.align	4
+ASLOCAL(main_panic)
+	string	"main() returned\0"
+	text
+	.align	8
 
 /*
  *	slave CPUs starts here
@@ -443,9 +440,6 @@ GLOBAL(idle_u)
 ASLOCAL(u0)
 	space	UPAGES * NBPG
 
-/* UPAGES get mapped to kstack */
-ASGLOBAL(kstack)
-	word	UADDR
 GLOBAL(ret_addr)
 	word 0
 /* XMEM spin lock -- to count CPUs */
diff --git a/sys/arch/luna88k/luna88k/machdep.c b/sys/arch/luna88k/luna88k/machdep.c
index fae882a9d6b..162d826f7d2 100644
--- a/sys/arch/luna88k/luna88k/machdep.c
+++ b/sys/arch/luna88k/luna88k/machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: machdep.c,v 1.22 2005/09/25 20:30:03 miod Exp $	*/
+/*	$OpenBSD: machdep.c,v 1.23 2005/10/12 19:05:39 miod Exp $	*/
 /*
  * Copyright (c) 1998, 1999, 2000, 2001 Steve Murphree, Jr.
  * Copyright (c) 1996 Nivas Madhur
@@ -127,9 +127,6 @@ void	slave_pre_main(void);
 int	slave_main(void);
 void	vector_init(m88k_exception_vector_area *, unsigned *);
 
-extern void load_u_area(struct proc *);
-extern void save_u_area(struct proc *, vaddr_t);
-
 vaddr_t size_memory(void);
 void powerdown(void);
 void get_fuse_rom_data(void);
@@ -138,8 +135,6 @@ char *nvram_by_symbol(char *);
 void get_autoboot_device(void);			/* in disksubr.c */
 int clockintr(void *);				/* in clock.c */
 
-vaddr_t interrupt_stack[MAX_CPUS];
-
 /*
  * *int_mask_reg[CPU]
  * Points to the hardware interrupt status register for each CPU.
@@ -397,7 +392,7 @@ cpu_startup()
 	int sz, i;
 	vsize_t size;
 	int base, residual;
-	vaddr_t minaddr, maxaddr, uarea_pages;
+	vaddr_t minaddr, maxaddr;
 
 	/*
 	 * Initialize error message buffer (at end of core).
@@ -491,17 +486,6 @@ cpu_startup()
 		panic("startup: table size inconsistency");
 
 	/*
-	 * Grab UADDR virtual address
-	 */
-	uarea_pages = UADDR;
-	uvm_map(kernel_map, (vaddr_t *)&uarea_pages, USPACE,
-	    NULL, UVM_UNKNOWN_OFFSET, 0,
-	      UVM_MAPFLAG(UVM_PROT_NONE, UVM_PROT_NONE, UVM_INH_NONE,
-	        UVM_ADV_NORMAL, 0));
-	if (uarea_pages != UADDR)
-		panic("uarea_pages %lx: UADDR not free", uarea_pages);
-
-	/*
 	 * Grab the OBIO space that we hardwired in pmap_bootstrap
 	 */
 	obiova = OBIO_START;
@@ -891,7 +875,6 @@ get_slave_stack()
 		panic("Cannot allocate slave stack for cpu %d",
 		    cpu_number());
 
-	interrupt_stack[cpu_number()] = addr;
 	return addr;
 }
 
@@ -1196,16 +1179,8 @@ luna88k_bootstrap()
 	uvm_page_physload(atop(avail_start), atop(avail_end),
 	    atop(avail_start), atop(avail_end),VM_FREELIST_DEFAULT);
 
-	/* Initialize cached PTEs for u-area mapping. */
-	save_u_area(&proc0, (vaddr_t)proc0paddr);
-
-	/*
-	 * Map proc0's u-area at the standard address (UADDR).
-	 */
-	load_u_area(&proc0);
-
 	/* Initialize the "u-area" pages. */
-	bzero((caddr_t)UADDR, UPAGES * PAGE_SIZE);
+	bzero((caddr_t)curpcb, USPACE);
 #ifdef DEBUG
 	printf("leaving luna88k_bootstrap()\n");
 #endif
diff --git a/sys/arch/m88k/include/cpu.h b/sys/arch/m88k/include/cpu.h
index b1a00496a60..bb5a253b778 100644
--- a/sys/arch/m88k/include/cpu.h
+++ b/sys/arch/m88k/include/cpu.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: cpu.h,v 1.5 2004/11/08 16:39:31 miod Exp $ */
+/*	$OpenBSD: cpu.h,v 1.6 2005/10/12 19:05:43 miod Exp $ */
 /*
  * Copyright (c) 1996 Nivas Madhur
  * Copyright (c) 1992, 1993
@@ -65,9 +65,10 @@
  * definitions of cpu-dependent requirements
  * referenced in generic code
  */
-#define	cpu_exec(p)	/* nothing */
-#define	cpu_wait(p)	/* nothing */
-#define	cpu_swapout(p)	/* nothing */
+#define	cpu_exec(p)		do { /* nothing */ } while (0)
+#define	cpu_wait(p)		do { /* nothing */ } while (0)
+#define	cpu_swapin(p)		do { /* nothing */ } while (0)
+#define	cpu_swapout(p)		do { /* nothing */ } while (0)
 
 /*
  * Arguments to hardclock and gatherstats encapsulate the previous
@@ -82,7 +83,7 @@ struct clockframe {
 
 #define	CLKF_USERMODE(framep)	((((struct trapframe *)(framep))->tf_epsr & PSR_MODE) == 0)
 #define	CLKF_PC(framep)		(((struct trapframe *)(framep))->tf_sxip & XIP_ADDR)
-#define	CLKF_INTR(framep)	(((struct trapframe *)(framep))->tf_r[31] >= UADDR)
+#define	CLKF_INTR(framep)	(0)	/* XXX temporary */
 
 /*
  * Get interrupt glue.
diff --git a/sys/arch/m88k/include/param.h b/sys/arch/m88k/include/param.h
index c86f46cbc6e..6a41569f6a3 100644
--- a/sys/arch/m88k/include/param.h
+++ b/sys/arch/m88k/include/param.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: param.h,v 1.6 2005/09/12 23:05:05 miod Exp $ */
+/*	$OpenBSD: param.h,v 1.7 2005/10/12 19:05:43 miod Exp $ */
 /*
  * Copyright (c) 1999 Steve Murphree, Jr.
  * Copyright (c) 1988 University of Utah.
@@ -81,8 +81,6 @@
 #define USPACE		(UPAGES * NBPG)
 #define	USPACE_ALIGN	(0)		/* u-area alignment 0-none */
 
-#define UADDR		0xeee00000	/* address of u */
-
 /*
  * Constants related to network buffer management.
  * MCLBYTES must be no larger than the software page size, and,
diff --git a/sys/arch/m88k/include/proc.h b/sys/arch/m88k/include/proc.h
index c658452b17a..cd51bdb3fee 100644
--- a/sys/arch/m88k/include/proc.h
+++ b/sys/arch/m88k/include/proc.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: proc.h,v 1.2 2005/05/18 16:44:37 miod Exp $ */
+/*	$OpenBSD: proc.h,v 1.3 2005/10/12 19:05:43 miod Exp $ */
 /*
  * Copyright (c) 1992, 1993
  *	The Regents of the University of California.  All rights reserved.
@@ -51,7 +51,6 @@ struct trapframe;
  */
 struct mdproc {
 	struct trapframe *md_tf;	/* trap/syscall registers */
-	int	md_upte[UPAGES];	/* ptes for mapping u page */
 
         /*
          * Single stepping is done by moving two breakpoints in the
diff --git a/sys/arch/m88k/m88k/eh_common.S b/sys/arch/m88k/m88k/eh_common.S
index c3a2e104d97..e9d69126496 100644
--- a/sys/arch/m88k/m88k/eh_common.S
+++ b/sys/arch/m88k/m88k/eh_common.S
@@ -1,4 +1,4 @@
-/*   $OpenBSD: eh_common.S,v 1.11 2005/09/25 20:30:03 miod Exp $	*/
+/*   $OpenBSD: eh_common.S,v 1.12 2005/10/12 19:05:44 miod Exp $	*/
 /*
  * Mach Operating System
  * Copyright (c) 1993-1991 Carnegie Mellon University
@@ -1010,9 +1010,9 @@ ASLOCAL(m88100_use_SR3_pcb)
 	 * Consequently, we never picked up a stack. Do so now.
 	 * R1 is currently free (saved in the exception frame pointed at by
 	 * r30) */
-	or.u	r1,   r0,   hi16(_ASM_LABEL(kstack))
-	ld	r1,   r1,   lo16(_ASM_LABEL(kstack))
-	addu	r1,   r1,   USIZE-SIZEOF_EF
+	or.u	r1,   r0,   hi16(_C_LABEL(curpcb))
+	ld	r1,   r1,   lo16(_C_LABEL(curpcb))
+	addu	r1,   r1,   USIZE - SIZEOF_EF
 	st	FLAGS,r1,   REG_OFF(EF_FLAGS)	/* store flags */
 	st	r31,  r1,   GENREG_OFF(31)	/* store r31 - now free */
 	st	r30,  r1,   REG_OFF(EF_SR3)	/* store old SR3 (pcb) */
@@ -1041,6 +1041,14 @@ ASLOCAL(m88100_pickup_stack)
 	or.u	r31,  r0,   hi16(_C_LABEL(curpcb))
 	ld	r31,  r31,  lo16(_C_LABEL(curpcb))
 	addu	r31,  r31,  PCB_USER_STATE	/* point to user save area */
+
+	/*
+	 * WARNING! Using pcb->user_state as the exception frame
+	 * AND stack pointer, means we can not afford using the stack
+	 * until we have saved enough and can go back to the top of the u area,
+	 * after the FPU is enabled.
+	 */
+
 	st	FLAGS,r31,  REG_OFF(EF_FLAGS)	/* save flags */
 	st	r1,   r31,  GENREG_OFF(1)	/* save prev. r1 (now free) */
 	ldcr	r1,   SR3			/* save previous r31 */
@@ -1523,8 +1531,8 @@ ASLOCAL(m88100_fpu_enable)
 	ld	r2,   r31,  REG_OFF(EF_EPSR)
 	bb1	PSR_SUPERVISOR_MODE_BIT, r2, 1f	/* if in kernel mode */
 
-	or.u	r31,  r0,   hi16(_ASM_LABEL(kstack))
-	ld	r31,  r31,  lo16(_ASM_LABEL(kstack))
+	or.u	r31,  r0,   hi16(_C_LABEL(curpcb))
+	ld	r31,  r31,  lo16(_C_LABEL(curpcb))
 	addu	r31,  r31,  USIZE	/* point at proper end */
 1:
 
@@ -2262,9 +2270,9 @@ ASLOCAL(m88110_use_SR3_pcb)
 	 * R1 is currently free (saved in the exception frame pointed at by
 	 * r30)
 	 */
-	or.u	r1,   r0,   hi16(_ASM_LABEL(kstack))
-	ld	r1,   r1,   lo16(_ASM_LABEL(kstack))
-	addu	r1,   r1,   USIZE-SIZEOF_EF
+	or.u	r1,   r0,   hi16(_C_LABEL(curpcb))
+	ld	r1,   r1,   lo16(_C_LABEL(curpcb))
+	addu	r1,   r1,   USIZE - SIZEOF_EF
 	st	FLAGS,r1,   REG_OFF(EF_FLAGS)	/* store flags */
 	st	r31,  r1,   GENREG_OFF(31)	/* store r31 - now free */
 	st	r30,  r1,   REG_OFF(EF_SR3)	/* store old SR3 (pcb) */
@@ -2294,6 +2302,14 @@ ASLOCAL(m88110_pickup_stack)
 	or.u	r31,  r0,   hi16(_C_LABEL(curpcb))
 	ld	r31,  r31,  lo16(_C_LABEL(curpcb))
 	addu	r31,  r31,  PCB_USER_STATE	/* point to user save area */
+
+	/*
+	 * WARNING! Using pcb->user_state as the exception frame
+	 * AND stack pointer, means we can not afford using the stack
+	 * until we have saved enough and can go back to the top of the u area,
+	 * after the FPU is enabled.
+	 */
+
 	st	FLAGS,r31,  REG_OFF(EF_FLAGS)	/* save flags */
 	st	r1,   r31,  GENREG_OFF(1)	/* save prev. r1 (now free)*/
 	ldcr	r1,   SR3			/* save previous r31 */
@@ -2518,8 +2534,8 @@ ASLOCAL(m88110_fpu_enable)
 	ld	r2,   r31,  REG_OFF(EF_EPSR)
 	bb1	PSR_SUPERVISOR_MODE_BIT, r2, 1f	/* if in kernel mode */
 
-	or.u	r31,  r0,   hi16(_ASM_LABEL(kstack))
-	ld	r31,  r31,  lo16(_ASM_LABEL(kstack))
+	or.u	r31,  r0,   hi16(_C_LABEL(curpcb))
+	ld	r31,  r31,  lo16(_C_LABEL(curpcb))
 	addu	r31,  r31,  USIZE		/* point at proper end */
 1:
 
diff --git a/sys/arch/m88k/m88k/m88k_machdep.c b/sys/arch/m88k/m88k/m88k_machdep.c
index bb177893c5d..baa23a75a2e 100644
--- a/sys/arch/m88k/m88k/m88k_machdep.c
+++ b/sys/arch/m88k/m88k/m88k_machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: m88k_machdep.c,v 1.4 2005/09/25 20:55:14 miod Exp $	*/
+/*	$OpenBSD: m88k_machdep.c,v 1.5 2005/10/12 19:05:44 miod Exp $	*/
 /*
  * Copyright (c) 1998, 1999, 2000, 2001 Steve Murphree, Jr.
  * Copyright (c) 1996 Nivas Madhur
@@ -75,8 +75,6 @@
 /* prototypes */
 void regdump(struct trapframe *f);
 void dumpsys(void);
-void save_u_area(struct proc *, vaddr_t);
-void load_u_area(struct proc *);
 void dumpconf(void);
 
 int longformat = 1;  /* for regdump() */
@@ -88,36 +86,6 @@ int longformat = 1;  /* for regdump() */
 int   safepri = IPL_NONE;
 
 /*
- * Setup u area ptes for u area double mapping.
- */
-
-void
-save_u_area(struct proc *p, vaddr_t va)
-{
-	int i;
-
-	for (i = 0; i < UPAGES; i++) {
-		p->p_md.md_upte[i] = *((pt_entry_t *)kvtopte(va));
-		va += PAGE_SIZE;
-	}
-}
-
-void
-load_u_area(struct proc *p)
-{
-	int i;
-	vaddr_t va;
-	pt_entry_t *t;
-
-	for (i = 0, va = UADDR; i < UPAGES; i++) {
-		t = kvtopte(va);
-		*t = p->p_md.md_upte[i];
-		va += PAGE_SIZE;
-	}
-	cmmu_flush_tlb(cpu_number(), 1, UADDR, UPAGES);
-}
-
-/*
  * Set registers on exec.
  * Clear all except sp and pc.
  */
diff --git a/sys/arch/m88k/m88k/pmap.c b/sys/arch/m88k/m88k/pmap.c
index 6c985e948f9..4f7ebb6adb2 100644
--- a/sys/arch/m88k/m88k/pmap.c
+++ b/sys/arch/m88k/m88k/pmap.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: pmap.c,v 1.12 2005/09/25 20:55:14 miod Exp $	*/
+/*	$OpenBSD: pmap.c,v 1.13 2005/10/12 19:05:44 miod Exp $	*/
 /*
  * Copyright (c) 2001-2004, Miodrag Vallat
  * Copyright (c) 1998-2001 Steve Murphree, Jr.
@@ -545,7 +545,6 @@ pmap_bootstrap(vaddr_t load_start)
 	sdt_entry_t *kmap;
 	vaddr_t vaddr, virt;
 	paddr_t s_text, e_text, kpdt_phys;
-	pt_entry_t *pte;
 	unsigned int kernel_pmap_size, pdt_size;
 	int i;
 	pmap_table_t ptable;
@@ -722,19 +721,6 @@ pmap_bootstrap(vaddr_t load_start)
 	virtual_avail = virt;
 
 	/*
-	 * Set translation for UPAGES at UADDR. The idea is we want to
-	 * have translations set up for UADDR. Later on, the ptes for
-	 * for this address will be set so that kstack will refer
-	 * to the u area. Make sure pmap knows about this virtual
-	 * address by doing vm_findspace on kernel_map.
-	 */
-
-	for (i = 0, virt = UADDR; i < UPAGES; i++, virt += PAGE_SIZE) {
-		if ((pte = pmap_pte(kernel_pmap, virt)) == PT_ENTRY_NULL)
-			pmap_expand_kmap(virt, VM_PROT_READ | VM_PROT_WRITE, 0);
-	}
-
-	/*
 	 * Switch to using new page tables
 	 */
 
diff --git a/sys/arch/m88k/m88k/process.S b/sys/arch/m88k/m88k/process.S
index 86309aa5bfe..f171ea433b1 100644
--- a/sys/arch/m88k/m88k/process.S
+++ b/sys/arch/m88k/m88k/process.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: process.S,v 1.8 2005/10/12 19:00:21 miod Exp $	*/
+/*	$OpenBSD: process.S,v 1.9 2005/10/12 19:05:44 miod Exp $	*/
 /*
  * Copyright (c) 1996 Nivas Madhur
  * All rights reserved.
@@ -225,15 +225,6 @@ ASLOCAL(cpu_switch_found)
 	 or	r2, r0, r9
 	or	r9, r0, r14		/* restore p saved in r14 */
 
-	/*
-	 * Since we are about to replace the u area mapping, we need to
-	 * switch to a neutral stack now.
-	 */
-	or.u	r31, r0, hi16(_ASM_LABEL(intstack_end))
-	or	r31,r31, lo16(_ASM_LABEL(intstack_end))
-
-	bsr.n    _C_LABEL(load_u_area)
-	 or	r2, r0, r9
 
 #if defined(MULTIPROCESSOR) || defined(LOCKDEBUG)
 	bsr	_C_LABEL(sched_unlock_idle)
diff --git a/sys/arch/m88k/m88k/vm_machdep.c b/sys/arch/m88k/m88k/vm_machdep.c
index 493f33d110d..5a0603657b5 100644
--- a/sys/arch/m88k/m88k/vm_machdep.c
+++ b/sys/arch/m88k/m88k/vm_machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vm_machdep.c,v 1.5 2005/09/25 20:55:14 miod Exp $	*/
+/*	$OpenBSD: vm_machdep.c,v 1.6 2005/10/12 19:05:44 miod Exp $	*/
 
 /*
  * Copyright (c) 1998 Steve Murphree, Jr.
@@ -91,7 +91,6 @@ cpu_fork(p1, p2, stack, stacksize, func, arg)
 	} *ksfp;
 	extern struct pcb *curpcb;
 	extern void proc_trampoline(void);
-        extern void save_u_area(struct proc *, vaddr_t);
 
 	/* Copy pcb from p1 to p2. */
 	if (p1 == curproc) {
@@ -107,9 +106,6 @@ cpu_fork(p1, p2, stack, stacksize, func, arg)
 	p2->p_addr->u_pcb.kernel_state.pcb_ipl = IPL_NONE;	/* XXX */
 	p2->p_md.md_tf = (struct trapframe *)USER_REGS(p2);
 
-	/*XXX these may not be necessary nivas */
-	save_u_area(p2, (vaddr_t)p2->p_addr);
-
 	/*
 	 * Create a switch frame for proc 2
 	 */
@@ -207,20 +203,6 @@ cpu_coredump(p, vp, cred, chdr)
 }
 
 /*
- * Finish a swapin operation.
- * We neded to update the cached PTEs for the user area in the
- * machine dependent part of the proc structure.
- */
-
-void
-cpu_swapin(struct proc *p)
-{
-        extern void save_u_area(struct proc *, vaddr_t);
-
-	save_u_area(p, (vaddr_t)p->p_addr);
-}
-
-/*
  * Map an IO request into kernel virtual address space.  Requests fall into
  * one of five catagories:
  *
diff --git a/sys/arch/mvme88k/mvme88k/locore.S b/sys/arch/mvme88k/mvme88k/locore.S
index 1ea081bf111..793fe7169ea 100644
--- a/sys/arch/mvme88k/mvme88k/locore.S
+++ b/sys/arch/mvme88k/mvme88k/locore.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: locore.S,v 1.41 2004/12/24 22:50:30 miod Exp $	*/
+/*	$OpenBSD: locore.S,v 1.42 2005/10/12 19:05:44 miod Exp $	*/
 /*
  * Copyright (c) 1998 Steve Murphree, Jr.
  * Copyright (c) 1996 Nivas Madhur
@@ -316,7 +316,6 @@ GLOBAL(start_text)
 ASLOCAL(master_start)
 	/*
 	 * Switch to interrupt stack
-	 * Use idle_u's stack instead?
 	 */
 	or.u	r31, r0,  hi16(_ASM_LABEL(intstack_end))
 	or	r31, r31, lo16(_ASM_LABEL(intstack_end))
@@ -340,34 +339,33 @@ ASLOCAL(master_start)
 	bsr.n	_C_LABEL(vector_init)
 	 ldcr	r2, VBR
 
-	/* still on int stack */
+	/*
+	 * mvme_bootstrap(), among other things, clears proc0's u area.
+	 * We are still using the interrupt stack here, thus we are not
+	 * affected...
+	 */
 	bsr	_C_LABEL(mvme_bootstrap)
 
 	/*
-	 * we now know our cpu number, so we
-	 * can set interrupt_stack[cpu_number()] = intstack
+	 * ...and we can switch to the u area stack now.
 	 */
-	ldcr	r10, SR1
-	extu	r10, r10, FLAG_CPU_FIELD_WIDTH<0>	/* r10 <-- CPU# */
-
-	/* figure interrupt_stack[cpu_number()] */
-	or.u	r11,  r0, hi16(_C_LABEL(interrupt_stack))
-	or	r11, r11, lo16(_C_LABEL(interrupt_stack))
-	or.u	r12, r0,  hi16(_C_LABEL(intstack))
-	or	r12, r12, lo16(_C_LABEL(intstack))
-	st	r12, r11 [r10]
-
-	/* switch to proc0 uarea */
-	or.u	r10, r0, hi16(UADDR)
-	or	r31, r10,lo16(UADDR)
-	addu	r31, r31, USIZE - 8
-
-	/* make the call: main() */
-	or.u	r2, r0, hi16(UADDR)
-	or	r2, r2,lo16(UADDR)
-	bsr.n	_C_LABEL(main)
-	 addu	r2, r2, USIZE - 8
-	bsr	_C_LABEL(panic)
+	or.u	r10, r0, hi16(_C_LABEL(curpcb))
+	ld	r31, r10,lo16(_C_LABEL(curpcb))
+	addu	r31, r31, USIZE
+
+	/* call main() - no arguments although main() still defines one */
+	bsr	_C_LABEL(main)
+
+	or.u	r2, r0, hi16(_ASM_LABEL(main_panic))
+	bsr.n	_C_LABEL(panic)
+	 or	r2, r2, lo16(_ASM_LABEL(main_panic))
+
+	data
+	.align	4
+ASLOCAL(main_panic)
+	string	"main() returned\0"
+	text
+	.align	8
 
 /*
  *	slave CPUs starts here
@@ -477,9 +475,6 @@ GLOBAL(idle_u)
 ASLOCAL(u0)
 	space	UPAGES * NBPG
 
-/* UPAGES get mapped to kstack */
-ASGLOBAL(kstack)
-	word	UADDR
 GLOBAL(ret_addr)
 	word 0
 /* XMEM spin lock -- to count CPUs */
diff --git a/sys/arch/mvme88k/mvme88k/machdep.c b/sys/arch/mvme88k/mvme88k/machdep.c
index 51f969e82a9..16e38ca0e01 100644
--- a/sys/arch/mvme88k/mvme88k/machdep.c
+++ b/sys/arch/mvme88k/mvme88k/machdep.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: machdep.c,v 1.167 2005/09/25 20:30:03 miod Exp $	*/
+/* $OpenBSD: machdep.c,v 1.168 2005/10/12 19:05:44 miod Exp $	*/
 /*
  * Copyright (c) 1998, 1999, 2000, 2001 Steve Murphree, Jr.
  * Copyright (c) 1996 Nivas Madhur
@@ -111,8 +111,6 @@ int	slave_main(void);
 void	vector_init(m88k_exception_vector_area *, unsigned *);
 void	_doboot(void);
 
-extern void load_u_area(struct proc *);
-extern void save_u_area(struct proc *, vaddr_t);
 extern void setlevel(unsigned int);
 
 extern void m187_bootstrap(void);
@@ -129,7 +127,6 @@ extern void m197_setupiackvectors(void);
 extern void m197_startup(void);
 
 intrhand_t intr_handlers[NVMEINTR];
-vaddr_t interrupt_stack[MAX_CPUS];
 
 /* board dependent pointers */
 void (*md_interrupt_func_ptr)(u_int, struct trapframe *);
@@ -363,7 +360,7 @@ cpu_startup()
 	int sz, i;
 	vsize_t size;
 	int base, residual;
-	vaddr_t minaddr, maxaddr, uarea_pages;
+	vaddr_t minaddr, maxaddr;
 
 	/*
 	 * Initialize error message buffer (at end of core).
@@ -394,17 +391,6 @@ cpu_startup()
 		panic("startup: table size inconsistency");
 
 	/*
-	 * Grab UADDR virtual address
-	 */
-	uarea_pages = UADDR;
-	uvm_map(kernel_map, (vaddr_t *)&uarea_pages, USPACE,
-	    NULL, UVM_UNKNOWN_OFFSET, 0,
-	      UVM_MAPFLAG(UVM_PROT_NONE, UVM_PROT_NONE, UVM_INH_NONE,
-	        UVM_ADV_NORMAL, 0));
-	if (uarea_pages != UADDR)
-		panic("uarea_pages %lx: UADDR not free", uarea_pages);
-
-	/*
 	 * Grab machine dependent memory spaces
 	 */
 	switch (brdtyp) {
@@ -840,7 +826,6 @@ get_slave_stack()
 		panic("Cannot allocate slave stack for cpu %d",
 		    cpu_number());
 
-	interrupt_stack[cpu_number()] = addr;
 	return addr;
 }
 
@@ -1184,16 +1169,8 @@ mvme_bootstrap()
 	uvm_page_physload(atop(avail_start), atop(avail_end),
 	    atop(avail_start), atop(avail_end), VM_FREELIST_DEFAULT);
 
-	/* Initialize cached PTEs for u-area mapping. */
-	save_u_area(&proc0, (vaddr_t)proc0paddr);
-
-	/*
-	 * Map proc0's u-area at the standard address (UADDR).
-	 */
-	load_u_area(&proc0);
-
 	/* Initialize the "u-area" pages. */
-	bzero((caddr_t)UADDR, UPAGES * PAGE_SIZE);
+	bzero((caddr_t)curpcb, USPACE);
 #ifdef DEBUG
 	printf("leaving mvme_bootstrap()\n");
 #endif