Don't index cpu_info by apic id, but by device unit number instead. Recent

Intel CPUs come up with apic id's >= 32, even on systems with less than 32
logical CPUs.

ok krw@, marco@; tested by deraadt@

12 files changed, 108 insertions, 132 deletions

diff --git a/sys/arch/amd64/amd64/cpu.c b/sys/arch/amd64/amd64/cpu.c
index aa84155b939..75a1ffaba82 100644
--- a/sys/arch/amd64/amd64/cpu.c
+++ b/sys/arch/amd64/amd64/cpu.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: cpu.c,v 1.28 2009/06/09 02:56:38 krw Exp $	*/
+/*	$OpenBSD: cpu.c,v 1.29 2010/04/01 19:47:59 kettenis Exp $	*/
 /* $NetBSD: cpu.c,v 1.1 2003/04/26 18:39:26 fvdl Exp $ */
 
 /*-
@@ -158,13 +158,6 @@ static void	cpu_copy_trampoline(void);
 void
 cpu_init_first(void)
 {
-	int cpunum = lapic_cpu_number();
-
-	if (cpunum != 0) {
-		cpu_info[0] = NULL;
-		cpu_info[cpunum] = &cpu_info_primary;
-	}
-
 	cpu_copy_trampoline();
 }
 #endif
@@ -225,7 +218,7 @@ cpu_attach(struct device *parent, struct device *self, void *aux)
 	struct cpu_attach_args *caa = aux;
 	struct cpu_info *ci;
 #if defined(MULTIPROCESSOR)
-	int cpunum = caa->cpu_number;
+	int cpunum = sc->sc_dev.dv_unit;
 	vaddr_t kstack;
 	struct pcb *pcb;
 #endif
@@ -248,10 +241,10 @@ cpu_attach(struct device *parent, struct device *self, void *aux)
 	} else {
 		ci = &cpu_info_primary;
 #if defined(MULTIPROCESSOR)
-		if (cpunum != lapic_cpu_number()) {
+		if (caa->cpu_number != lapic_cpu_number()) {
 			panic("%s: running cpu is at apic %d"
 			    " instead of at expected %d",
-			    sc->sc_dev.dv_xname, lapic_cpu_number(), cpunum);
+			    sc->sc_dev.dv_xname, lapic_cpu_number(), caa->cpu_number);
 		}
 #endif
 	}
@@ -262,7 +255,7 @@ cpu_attach(struct device *parent, struct device *self, void *aux)
 	ci->ci_dev = self;
 	ci->ci_apicid = caa->cpu_number;
 #ifdef MULTIPROCESSOR
-	ci->ci_cpuid = ci->ci_apicid;
+	ci->ci_cpuid = cpunum;
 #else
 	ci->ci_cpuid = 0;	/* False for APs, but they're not used anyway */
 #endif
diff --git a/sys/arch/amd64/amd64/db_interface.c b/sys/arch/amd64/amd64/db_interface.c
index 36455c96a3b..a6d95bc986d 100644
--- a/sys/arch/amd64/amd64/db_interface.c
+++ b/sys/arch/amd64/amd64/db_interface.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: db_interface.c,v 1.15 2008/10/03 21:57:25 weingart Exp $	*/
+/*	$OpenBSD: db_interface.c,v 1.16 2010/04/01 19:47:59 kettenis Exp $	*/
 /*	$NetBSD: db_interface.c,v 1.1 2003/04/26 18:39:27 fvdl Exp $	*/
 
 /*
@@ -83,7 +83,6 @@ void db_cpuinfo_cmd(db_expr_t, int, db_expr_t, char *);
 void db_startproc_cmd(db_expr_t, int, db_expr_t, char *);
 void db_stopproc_cmd(db_expr_t, int, db_expr_t, char *);
 void db_ddbproc_cmd(db_expr_t, int, db_expr_t, char *);
-int db_cpuid2apic(int);
 #endif
 
 /*
@@ -162,19 +161,6 @@ kdb_trap(int type, int code, db_regs_t *regs)
 
 
 #ifdef MULTIPROCESSOR
-int
-db_cpuid2apic(int id)
-{
-	int apic;
-
-	for (apic = 0; apic < MAXCPUS; apic++) {
-		if (cpu_info[apic] != NULL &&
-		    CPU_INFO_UNIT(cpu_info[apic]) == id)
-			return (apic);
-	}
-	return (-1);
-}
-
 void
 db_cpuinfo_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
 {
@@ -212,20 +198,18 @@ db_cpuinfo_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
 void
 db_startproc_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
 {
-	int apic;
+	int i;
 
 	if (have_addr) {
-		apic = db_cpuid2apic(addr);
-		if (apic >= 0 && apic < MAXCPUS &&
-		    cpu_info[apic] != NULL && apic != cpu_number())
-			db_startcpu(apic);
+		if (addr >= 0 && addr < MAXCPUS &&
+		    cpu_info[addr] != NULL && addr != cpu_number())
+			db_startcpu(addr);
 		else
 			db_printf("Invalid cpu %d\n", (int)addr);
 	} else {
-		for (apic = 0; apic < MAXCPUS; apic++) {
-			if (cpu_info[apic] != NULL && apic != cpu_number()) {
-				db_startcpu(apic);
-			}
+		for (i = 0; i < MAXCPUS; i++) {
+			if (cpu_info[i] != NULL && i != cpu_number())
+				db_startcpu(i);
 		}
 	}
 }
@@ -233,20 +217,18 @@ db_startproc_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
 void
 db_stopproc_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
 {
-	int apic;
+	int i;
 
 	if (have_addr) {
-		apic = db_cpuid2apic(addr);
-		if (apic >= 0 && apic < MAXCPUS &&
-		    cpu_info[apic] != NULL && apic != cpu_number())
-			db_stopcpu(apic);
+		if (addr >= 0 && addr < MAXCPUS &&
+		    cpu_info[addr] != NULL && addr != cpu_number())
+			db_stopcpu(addr);
 		else
 			db_printf("Invalid cpu %d\n", (int)addr);
 	} else {
-		for (apic = 0; apic < MAXCPUS; apic++) {
-			if (cpu_info[apic] != NULL && apic != cpu_number()) {
-				db_stopcpu(apic);
-			}
+		for (i = 0; i < MAXCPUS; i++) {
+			if (cpu_info[i] != NULL && i != cpu_number())
+				db_stopcpu(i);
 		}
 	}
 }
@@ -254,14 +236,11 @@ db_stopproc_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
 void
 db_ddbproc_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
 {
-	int apic;
-
 	if (have_addr) {
-		apic = db_cpuid2apic(addr);
-		if (apic >= 0 && apic < MAXCPUS &&
-		    cpu_info[apic] != NULL && apic != cpu_number()) {
-			db_stopcpu(apic);
-			db_switch_to_cpu = apic;
+		if (addr >= 0 && addr < MAXCPUS &&
+		    cpu_info[addr] != NULL && addr != cpu_number()) {
+			db_stopcpu(addr);
+			db_switch_to_cpu = addr;
 			db_switch_cpu = 1;
 			db_cmd_loop_done = 1;
 		} else {
diff --git a/sys/arch/amd64/amd64/genassym.cf b/sys/arch/amd64/amd64/genassym.cf
index 381b7d0438c..602221a923f 100644
--- a/sys/arch/amd64/amd64/genassym.cf
+++ b/sys/arch/amd64/amd64/genassym.cf
@@ -1,4 +1,4 @@
-#	$OpenBSD: genassym.cf,v 1.21 2009/06/09 02:56:38 krw Exp $
+#	$OpenBSD: genassym.cf,v 1.22 2010/04/01 19:47:59 kettenis Exp $
 #	Written by Artur Grabowski art@openbsd.org, Public Domain
 
 include <sys/param.h>
@@ -94,6 +94,7 @@ member	pcb_fpcpu
 struct	cpu_info
 member	CPU_INFO_SCRATCH	ci_scratch
 member  CPU_INFO_SELF		ci_self
+member  CPU_INFO_APICID		ci_apicid
 member  CPU_INFO_RESCHED	ci_want_resched
 member  CPU_INFO_CURPROC	ci_curproc
 member  CPU_INFO_CURPCB		ci_curpcb
diff --git a/sys/arch/amd64/amd64/lapic.c b/sys/arch/amd64/amd64/lapic.c
index c1fab756130..2dbd9acb983 100644
--- a/sys/arch/amd64/amd64/lapic.c
+++ b/sys/arch/amd64/amd64/lapic.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: lapic.c,v 1.22 2009/08/10 17:04:37 deraadt Exp $	*/
+/*	$OpenBSD: lapic.c,v 1.23 2010/04/01 19:47:59 kettenis Exp $	*/
 /* $NetBSD: lapic.c,v 1.2 2003/05/08 01:04:35 fvdl Exp $ */
 
 /*-
@@ -113,7 +113,7 @@ lapic_map(paddr_t lapic_base)
 	invlpg(va);
 
 #ifdef MULTIPROCESSOR
-	cpu_init_first();	/* catch up to changed cpu_number() */
+	cpu_init_first();
 #endif
 
 	lapic_tpr = s;
diff --git a/sys/arch/amd64/amd64/mptramp.S b/sys/arch/amd64/amd64/mptramp.S
index 72b17773951..98d9f861f2d 100644
--- a/sys/arch/amd64/amd64/mptramp.S
+++ b/sys/arch/amd64/amd64/mptramp.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mptramp.S,v 1.5 2008/06/26 05:42:09 ray Exp $	*/
+/*	$OpenBSD: mptramp.S,v 1.6 2010/04/01 19:47:59 kettenis Exp $	*/
 /*	$NetBSD: mptramp.S,v 1.1 2003/04/26 18:39:30 fvdl Exp $	*/
 
 /*-
@@ -208,9 +208,15 @@ _TRMP_LABEL(mptramp_longmode)
 
 	
 _C_LABEL(cpu_spinup_trampoline_end):	#end of code copied to MP_TRAMPOLINE
-	movl	_C_LABEL(local_apic)+LAPIC_ID,%ecx
-	shrl	$LAPIC_ID_SHIFT,%ecx
+	movl	_C_LABEL(local_apic)+LAPIC_ID,%eax
+	shrl	$LAPIC_ID_SHIFT,%eax
+	xorq	%rcx,%rcx
+1:
 	movq	_C_LABEL(cpu_info)(,%rcx,8),%rdi
+	incq	%rcx
+	movl	CPU_INFO_APICID(%rdi),%edx
+	cmpl	%eax,%edx
+	jne	1b
 
 	movq	CPU_INFO_IDLE_PCB(%rdi),%rsi
 
diff --git a/sys/arch/i386/i386/cpu.c b/sys/arch/i386/i386/cpu.c
index b586ab0cc42..36b1f217f6d 100644
--- a/sys/arch/i386/i386/cpu.c
+++ b/sys/arch/i386/i386/cpu.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: cpu.c,v 1.35 2009/06/03 00:49:12 art Exp $	*/
+/*	$OpenBSD: cpu.c,v 1.36 2010/04/01 19:48:50 kettenis Exp $	*/
 /* $NetBSD: cpu.c,v 1.1.2.7 2000/06/26 02:04:05 sommerfeld Exp $ */
 
 /*-
@@ -144,13 +144,6 @@ void	cpu_copy_trampoline(void);
 void
 cpu_init_first()
 {
-	int cpunum = lapic_cpu_number();
-
-	if (cpunum != 0) {
-		cpu_info[0] = NULL;
-		cpu_info[cpunum] = &cpu_info_primary;
-	}
-
 	cpu_copy_trampoline();
 }
 #endif
@@ -181,7 +174,7 @@ cpu_attach(struct device *parent, struct device *self, void *aux)
 	struct cpu_attach_args *caa = (struct cpu_attach_args *)aux;
 
 #ifdef MULTIPROCESSOR
-	int cpunum = caa->cpu_number;
+	int cpunum = ci->ci_dev.dv_unit;
 	vaddr_t kstack;
 	struct pcb *pcb;
 #endif
@@ -195,10 +188,10 @@ cpu_attach(struct device *parent, struct device *self, void *aux)
 	} else {
 		ci = &cpu_info_primary;
 #ifdef MULTIPROCESSOR
-		if (cpunum != lapic_cpu_number()) {
+		if (caa->cpu_number != lapic_cpu_number()) {
 			panic("%s: running cpu is at apic %d"
 			    " instead of at expected %d",
-			    self->dv_xname, lapic_cpu_number(), cpunum);
+			    self->dv_xname, lapic_cpu_number(), caa->cpu_number);
 		}
 #endif
 		bcopy(self, &ci->ci_dev, sizeof *self);
@@ -207,7 +200,7 @@ cpu_attach(struct device *parent, struct device *self, void *aux)
 	ci->ci_self = ci;
 	ci->ci_apicid = caa->cpu_number;
 #ifdef MULTIPROCESSOR
-	ci->ci_cpuid = ci->ci_apicid;
+	ci->ci_cpuid = cpunum;
 #else
 	ci->ci_cpuid = 0;	/* False for APs, so what, they're not used */
 #endif
diff --git a/sys/arch/i386/i386/db_interface.c b/sys/arch/i386/i386/db_interface.c
index f0d01c29d96..5d5590f42d6 100644
--- a/sys/arch/i386/i386/db_interface.c
+++ b/sys/arch/i386/i386/db_interface.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: db_interface.c,v 1.25 2007/11/16 16:16:06 deraadt Exp $	*/
+/*	$OpenBSD: db_interface.c,v 1.26 2010/04/01 19:48:50 kettenis Exp $	*/
 /*	$NetBSD: db_interface.c,v 1.22 1996/05/03 19:42:00 christos Exp $	*/
 
 /*
@@ -77,7 +77,6 @@ void db_cpuinfo_cmd(db_expr_t, int, db_expr_t, char *);
 void db_startproc_cmd(db_expr_t, int, db_expr_t, char *);
 void db_stopproc_cmd(db_expr_t, int, db_expr_t, char *);
 void db_ddbproc_cmd(db_expr_t, int, db_expr_t, char *);
-int db_cpuid2apic(int);
 #endif /* MULTIPROCESSOR */
 
 /*
@@ -210,19 +209,6 @@ db_sysregs_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
 }
 
 #ifdef MULTIPROCESSOR
-int
-db_cpuid2apic(int id)
-{
-	int apic;
-
-	for (apic = 0; apic < MAXCPUS; apic++) {
-		if (cpu_info[apic] != NULL &&
-		    cpu_info[apic]->ci_dev.dv_unit == id)
-			return (apic);
-	}
-	return (-1);
-}
-
 void
 db_cpuinfo_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
 {
@@ -260,20 +246,18 @@ db_cpuinfo_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
 void
 db_startproc_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
 {
-	int apic;
+	int i;
 
 	if (have_addr) {
-		apic = db_cpuid2apic(addr);
-		if (apic >= 0 && apic < MAXCPUS &&
-		    cpu_info[apic] != NULL && apic != cpu_number())
-			db_startcpu(apic);
+		if (addr >= 0 && addr < MAXCPUS &&
+		    cpu_info[addr] != NULL && addr != cpu_number())
+			db_startcpu(addr);
 		else
 			db_printf("Invalid cpu %d\n", (int)addr);
 	} else {
-		for (apic = 0; apic < MAXCPUS; apic++) {
-			if (cpu_info[apic] != NULL && apic != cpu_number()) {
-				db_startcpu(apic);
-			}
+		for (i = 0; i < MAXCPUS; i++) {
+			if (cpu_info[i] != NULL && i != cpu_number())
+				db_startcpu(i);
 		}
 	}
 }
@@ -281,19 +265,18 @@ db_startproc_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
 void
 db_stopproc_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
 {
-	int apic;
+	int i;
 
 	if (have_addr) {
-		apic = db_cpuid2apic(addr);
-		if (apic >= 0 && apic < MAXCPUS &&
-		    cpu_info[apic] != NULL && apic != cpu_number())
-			db_stopcpu(apic);
+		if (addr >= 0 && addr < MAXCPUS &&
+		    cpu_info[addr] != NULL && addr != cpu_number())
+			db_stopcpu(addr);
 		else
 			db_printf("Invalid cpu %d\n", (int)addr);
 	} else {
-		for (apic = 0; apic < MAXCPUS; apic++) {
-			if (cpu_info[apic] != NULL && apic != cpu_number()) {
-				db_stopcpu(apic);
+		for (i = 0; i < MAXCPUS; i++) {
+			if (cpu_info[i] != NULL && i != cpu_number()) {
+				db_stopcpu(i);
 			}
 		}
 	}
@@ -302,14 +285,11 @@ db_stopproc_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
 void
 db_ddbproc_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
 {
-	int apic;
-
 	if (have_addr) {
-		apic = db_cpuid2apic(addr);
-		if (apic >= 0 && apic < MAXCPUS &&
-		    cpu_info[apic] != NULL && apic != cpu_number()) {
-			db_stopcpu(apic);
-			db_switch_to_cpu = apic;
+		if (addr >= 0 && addr < MAXCPUS &&
+		    cpu_info[addr] != NULL && addr != cpu_number()) {
+			db_stopcpu(addr);
+			db_switch_to_cpu = addr;
 			db_switch_cpu = 1;
 			db_cmd_loop_done = 1;
 		} else {
diff --git a/sys/arch/i386/i386/genassym.cf b/sys/arch/i386/i386/genassym.cf
index 6506af35feb..678ce236452 100644
--- a/sys/arch/i386/i386/genassym.cf
+++ b/sys/arch/i386/i386/genassym.cf
@@ -1,4 +1,4 @@
-#	$OpenBSD: genassym.cf,v 1.29 2009/06/03 00:49:12 art Exp $
+#	$OpenBSD: genassym.cf,v 1.30 2010/04/01 19:48:50 kettenis Exp $
 #
 # Copyright (c) 1982, 1990 The Regents of the University of California.
 # All rights reserved.
@@ -191,6 +191,7 @@ define	IP_DST			offsetof(struct ip, ip_dst)
 define	P_MD_TSS_SEL		offsetof(struct proc, p_md.md_tss_sel)
 
 define	CPU_INFO_SELF		offsetof(struct cpu_info, ci_self)
+define	CPU_INFO_APICID		offsetof(struct cpu_info, ci_apicid)
 define	CPU_INFO_CURPROC	offsetof(struct cpu_info, ci_curproc)
 define	CPU_INFO_CURPCB		offsetof(struct cpu_info, ci_curpcb)
 define	CPU_INFO_NAME		offsetof(struct cpu_info, ci_dev.dv_xname)
diff --git a/sys/arch/i386/i386/ipifuncs.c b/sys/arch/i386/i386/ipifuncs.c
index aeba0d7df00..f0facf0b339 100644
--- a/sys/arch/i386/i386/ipifuncs.c
+++ b/sys/arch/i386/i386/ipifuncs.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ipifuncs.c,v 1.14 2009/11/29 17:11:30 kettenis Exp $	*/
+/*	$OpenBSD: ipifuncs.c,v 1.15 2010/04/01 19:48:50 kettenis Exp $	*/
 /* $NetBSD: ipifuncs.c,v 1.1.2.3 2000/06/26 02:04:06 sommerfeld Exp $ */
 
 /*-
@@ -148,7 +148,7 @@ i386_send_ipi(struct cpu_info *ci, int ipimask)
 	if (!(ci->ci_flags & CPUF_RUNNING))
 		return ENOENT;
 
-	ret = i386_ipi(LAPIC_IPI_VECTOR, ci->ci_cpuid, LAPIC_DLMODE_FIXED);
+	ret = i386_ipi(LAPIC_IPI_VECTOR, ci->ci_apicid, LAPIC_DLMODE_FIXED);
 	if (ret != 0) {
 		printf("ipi of %x from %s to %s failed\n",
 		    ipimask, curcpu()->ci_dev.dv_xname, ci->ci_dev.dv_xname);
@@ -163,7 +163,7 @@ i386_fast_ipi(struct cpu_info *ci, int ipi)
 	if (!(ci->ci_flags & CPUF_RUNNING))
 		return (ENOENT);
 
-	return (i386_ipi(ipi, ci->ci_cpuid, LAPIC_DLMODE_FIXED));
+	return (i386_ipi(ipi, ci->ci_apicid, LAPIC_DLMODE_FIXED));
 }
 
 void
diff --git a/sys/arch/i386/i386/kvm86call.S b/sys/arch/i386/i386/kvm86call.S
index de48f15ef8a..276a149a32e 100644
--- a/sys/arch/i386/i386/kvm86call.S
+++ b/sys/arch/i386/i386/kvm86call.S
@@ -1,4 +1,4 @@
-/* $OpenBSD: kvm86call.S,v 1.4 2006/12/11 23:45:13 gwk Exp $ */
+/* $OpenBSD: kvm86call.S,v 1.5 2010/04/01 19:48:50 kettenis Exp $ */
 /* $NetBSD: kvm86call.S,v 1.7 2006/04/11 17:14:07 drochner Exp $ */
 
 /*-
@@ -78,12 +78,17 @@ ENTRY(kvm86_call)
 	rep
 	movsl				/* copy frame to new stack */
 
-#ifdef MULTIPROCESSOR	
-	movl	_C_LABEL(local_apic)+LAPIC_ID,%ecx
-	shrl	$LAPIC_ID_SHIFT,%ecx
-	leal	0(,%ecx,4),%ecx
-	movl	_C_LABEL(cpu_info)(%ecx),%edx
-	movl	%edx,%ecx
+#ifdef MULTIPROCESSOR
+	movl	_C_LABEL(local_apic)+LAPIC_ID,%eax
+	shrl	$LAPIC_ID_SHIFT,%eax
+	xorl	%ebx,%ebx
+1:
+	leal	0(,%ebx,4),%ecx
+	incl	%ebx
+	movl	_C_LABEL(cpu_info)(%ecx),%ecx
+	movl	CPU_INFO_APICID(%ecx),%edx
+	cmpl	%eax,%edx
+	jne 1b
 #else
 	leal	_C_LABEL(cpu_info_primary),%ecx
 #endif
@@ -172,10 +177,16 @@ ENTRY(kvm86_ret)
 
 	
 #ifdef MULTIPROCESSOR
-	movl	_C_LABEL(local_apic)+LAPIC_ID,%ecx
-	shrl	$LAPIC_ID_SHIFT,%ecx
-	leal	0(,%ecx,4),%ecx
+	movl	_C_LABEL(local_apic)+LAPIC_ID,%eax
+	shrl	$LAPIC_ID_SHIFT,%eax
+	xorl	%ebx,%ebx
+1:
+	leal	0(,%ebx,4),%ecx
+	incl	%ebx
 	movl	_C_LABEL(cpu_info)(%ecx),%ecx
+	movl	CPU_INFO_APICID(%ecx),%edx
+	cmpl	%eax,%edx
+	jne 1b
 	movl	CPU_INFO_GDT(%ecx),%eax
 #else
 	leal	_C_LABEL(cpu_info_primary),%ecx
@@ -191,10 +202,16 @@ ENTRY(kvm86_ret)
 
 
 #ifdef MULTIPROCESSOR	
-	movl	_C_LABEL(local_apic)+LAPIC_ID,%ecx
-	shrl	$LAPIC_ID_SHIFT,%ecx
-	leal	0(,%ecx,4),%ecx
+	movl	_C_LABEL(local_apic)+LAPIC_ID,%eax
+	shrl	$LAPIC_ID_SHIFT,%eax
+	xorl	%ebx,%ebx
+1:
+	leal	0(,%ebx,4),%ecx
+	incl	%ebx
 	movl	_C_LABEL(cpu_info)(%ecx),%ecx
+	movl	CPU_INFO_APICID(%ecx),%edx
+	cmpl	%eax,%edx
+	jne 1b
 #else
 	leal	_C_LABEL(cpu_info_primary),%ecx
 #endif
diff --git a/sys/arch/i386/i386/lapic.c b/sys/arch/i386/i386/lapic.c
index 77f682212ea..11760a497d0 100644
--- a/sys/arch/i386/i386/lapic.c
+++ b/sys/arch/i386/i386/lapic.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: lapic.c,v 1.26 2009/08/10 17:04:39 deraadt Exp $	*/
+/*	$OpenBSD: lapic.c,v 1.27 2010/04/01 19:48:50 kettenis Exp $	*/
 /* $NetBSD: lapic.c,v 1.1.2.8 2000/02/23 06:10:50 sommerfeld Exp $ */
 
 /*-
@@ -90,7 +90,7 @@ lapic_map(paddr_t lapic_base)
 	invlpg(va);
 
 #ifdef MULTIPROCESSOR
-	cpu_init_first();	/* catch up to changed cpu_number() */
+	cpu_init_first();
 #endif
 
 	lapic_tpr = s;
diff --git a/sys/arch/i386/i386/mptramp.s b/sys/arch/i386/i386/mptramp.s
index 499a36dd722..e7d521e52e5 100644
--- a/sys/arch/i386/i386/mptramp.s
+++ b/sys/arch/i386/i386/mptramp.s
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mptramp.s,v 1.12 2009/07/10 13:51:47 jsg Exp $	*/
+/*	$OpenBSD: mptramp.s,v 1.13 2010/04/01 19:48:50 kettenis Exp $	*/
 
 /*-
  * Copyright (c) 2000 The NetBSD Foundation, Inc.
@@ -171,10 +171,16 @@ _TRMP_LABEL(mp_startup)
 # ok, we're now running with paging enabled and sharing page tables with cpu0.
 # figure out which processor we really are, what stack we should be on, etc.
 
-	movl	_C_LABEL(local_apic)+LAPIC_ID,%ecx
-	shrl	$LAPIC_ID_SHIFT,%ecx
-	leal	0(,%ecx,4),%ecx
+	movl	_C_LABEL(local_apic)+LAPIC_ID,%eax
+	shrl	$LAPIC_ID_SHIFT,%eax
+	xorl	%ebx,%ebx
+1:
+	leal	0(,%ebx,4),%ecx
+	incl	%ebx
 	movl	_C_LABEL(cpu_info)(%ecx),%ecx
+	movl	CPU_INFO_APICID(%ecx),%edx
+	cmpl	%eax,%edx
+	jne 1b
 
 	HALTT(0x7, %ecx)