[PATCH] APIC enumeration fixes

The following patch appears sound according to an audit to ensure that all
of the codepaths where it was introduced were called after the APIC
fixmappings were set up.

This patch introduces get_physical_broadcast(), which checks the version ID
of the local APIC to determine whether it's a serial APIC or xAPIC, and
returns the correct physical broadcast ID.  It replaces all uses of
APIC_BROADCAST_ID and IO_APIC_MAX_ID with this in order to ensure.  It also
changes the checks during MP table parsing so the APIC ID is checked in
tandem with the version number.

I'm holding out for some kind of testing to get an idea of whether this
covers the cases or introduces regressions, or whatever.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/i386/kernel/io_apic.c

@@ -722,6 +722,17 @@ static int __init ioapic_pirq_setup(char *str)
 
 __setup("pirq=", ioapic_pirq_setup);
 
+static int get_physical_broadcast(void)
+{
+	unsigned int lvr, version;
+	lvr = apic_read(APIC_LVR);
+	version = GET_APIC_VERSION(lvr);
+	if (version >= 0x14)
+		return 0xff;
+	else
+		return 0xf;
+}
+
 /*
  * Find the IRQ entry number of a certain pin.
  */
@@ -1326,7 +1337,7 @@ void __init print_IO_APIC(void)
 	printk(KERN_DEBUG ".......    : physical APIC id: %02X\n", reg_00.bits.ID);
 	printk(KERN_DEBUG ".......    : Delivery Type: %X\n", reg_00.bits.delivery_type);
 	printk(KERN_DEBUG ".......    : LTS          : %X\n", reg_00.bits.LTS);
-	if (reg_00.bits.ID >= APIC_BROADCAST_ID)
+	if (reg_00.bits.ID >= get_physical_broadcast())
 		UNEXPECTED_IO_APIC();
 	if (reg_00.bits.__reserved_1 || reg_00.bits.__reserved_2)
 		UNEXPECTED_IO_APIC();
@@ -1642,7 +1653,7 @@ static void __init setup_ioapic_ids_from_mpc(void)
 		
 		old_id = mp_ioapics[apic].mpc_apicid;
 
-		if (mp_ioapics[apic].mpc_apicid >= APIC_BROADCAST_ID) {
+		if (mp_ioapics[apic].mpc_apicid >= get_physical_broadcast()) {
 			printk(KERN_ERR "BIOS bug, IO-APIC#%d ID is %d in the MPC table!...\n",
 				apic, mp_ioapics[apic].mpc_apicid);
 			printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
@@ -1663,10 +1674,10 @@ static void __init setup_ioapic_ids_from_mpc(void)
 					mp_ioapics[apic].mpc_apicid)) {
 			printk(KERN_ERR "BIOS bug, IO-APIC#%d ID %d is already used!...\n",
 				apic, mp_ioapics[apic].mpc_apicid);
-			for (i = 0; i < APIC_BROADCAST_ID; i++)
+			for (i = 0; i < get_physical_broadcast(); i++)
 				if (!physid_isset(i, phys_id_present_map))
 					break;
-			if (i >= APIC_BROADCAST_ID)
+			if (i >= get_physical_broadcast())
 				panic("Max APIC ID exceeded!\n");
 			printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
 				i);
@@ -2263,8 +2274,6 @@ late_initcall(io_apic_bug_finalize);
 
 #ifdef CONFIG_ACPI_BOOT
 
-#define IO_APIC_MAX_ID APIC_BROADCAST_ID
-
 int __init io_apic_get_unique_id (int ioapic, int apic_id)
 {
 	union IO_APIC_reg_00 reg_00;
@@ -2289,7 +2298,7 @@ int __init io_apic_get_unique_id (int ioapic, int apic_id)
 	reg_00.raw = io_apic_read(ioapic, 0);
 	spin_unlock_irqrestore(&ioapic_lock, flags);
 
-	if (apic_id >= IO_APIC_MAX_ID) {
+	if (apic_id >= get_physical_broadcast()) {
 		printk(KERN_WARNING "IOAPIC[%d]: Invalid apic_id %d, trying "
 			"%d\n", ioapic, apic_id, reg_00.bits.ID);
 		apic_id = reg_00.bits.ID;
@@ -2301,12 +2310,12 @@ int __init io_apic_get_unique_id (int ioapic, int apic_id)
 	 */
 	if (check_apicid_used(apic_id_map, apic_id)) {
 
-		for (i = 0; i < IO_APIC_MAX_ID; i++) {
+		for (i = 0; i < get_physical_broadcast(); i++) {
 			if (!check_apicid_used(apic_id_map, i))
 				break;
 		}
 
-		if (i == IO_APIC_MAX_ID)
+		if (i == get_physical_broadcast())
 			panic("Max apic_id exceeded!\n");
 
 		printk(KERN_WARNING "IOAPIC[%d]: apic_id %d already used, "

arch/i386/kernel/mpparse.c

@@ -23,6 +23,7 @@
 #include <linux/smp_lock.h>
 #include <linux/kernel_stat.h>
 #include <linux/mc146818rtc.h>
+#include <linux/bitops.h>
 
 #include <asm/smp.h>
 #include <asm/acpi.h>
@@ -103,6 +104,31 @@ static int __init mpf_checksum(unsigned char *mp, int len)
 static int mpc_record; 
 static struct mpc_config_translation *translation_table[MAX_MPC_ENTRY] __initdata;
 
+#ifdef CONFIG_X86_NUMAQ
+static int MP_valid_apicid(int apicid, int version)
+{
+	return hweight_long(i & 0xf) == 1 && (i >> 4) != 0xf;
+}
+#else
+static int MP_valid_apicid(int apicid, int version)
+{
+	if (version >= 0x14)
+		return apicid < 0xff;
+	else
+		return apicid < 0xf;
+}
+#endif
+
+static void MP_mark_version_physids(int version)
+{
+	int i;
+
+	for (i = 0; i < MAX_APICS; ++i) {
+		if (!MP_valid_apicid(i, version))
+			physid_set(i, phys_cpu_present_map);
+	}
+}
+
 void __init MP_processor_info (struct mpc_config_processor *m)
 {
  	int ver, apicid;
@@ -179,14 +205,16 @@ void __init MP_processor_info (struct mpc_config_processor *m)
 		return;
 	}
 	num_processors++;
+	ver = m->mpc_apicver;
 
-	if (MAX_APICS - m->mpc_apicid <= 0) {
+	if (MP_valid_apicid(m->mpc_apicid, ver))
+		MP_mark_version_physids(ver);
+	else {
 		printk(KERN_WARNING "Processor #%d INVALID. (Max ID: %d).\n",
 			m->mpc_apicid, MAX_APICS);
 		--num_processors;
 		return;
 	}
-	ver = m->mpc_apicver;
 
 	tmp = apicid_to_cpu_present(apicid);
 	physids_or(phys_cpu_present_map, phys_cpu_present_map, tmp);

arch/i386/mach-visws/mpparse.c

@@ -57,12 +57,12 @@ void __init MP_processor_info (struct mpc_config_processor *m)
 		boot_cpu_logical_apicid = logical_apicid;
 	}
 
-	if (m->mpc_apicid > MAX_APICS) {
+	ver = m->mpc_apicver;
+	if ((ver >= 0x14 && m->mpc_apicid >= 0xff) || m->mpc_apicid >= 0xf) {
 		printk(KERN_ERR "Processor #%d INVALID. (Max ID: %d).\n",
 			m->mpc_apicid, MAX_APICS);
 		return;
 	}
-	ver = m->mpc_apicver;
 
 	apic_cpus = apicid_to_cpu_present(m->mpc_apicid);
 	physids_or(phys_cpu_present_map, phys_cpu_present_map, apic_cpus);
@@ -75,6 +75,14 @@ void __init MP_processor_info (struct mpc_config_processor *m)
 			m->mpc_apicid);
 		ver = 0x10;
 	}
+	if (ver >= 0x14)
+		physid_set(0xff, phys_cpu_present_map);
+	else {
+		int i;
+
+		for (i = 0xf; i < MAX_APICS; ++i)
+			physid_set(i, phys_cpu_present_map);
+	}
 	apic_version[m->mpc_apicid] = ver;
 }
 

include/asm-i386/genapic.h

@@ -25,7 +25,6 @@ struct genapic {
 	cpumask_t (*target_cpus)(void);
 	int int_delivery_mode;
 	int int_dest_mode; 
-	int apic_broadcast_id; 
 	int ESR_DISABLE;
 	int apic_destination_logical;
 	unsigned long (*check_apicid_used)(physid_mask_t bitmap, int apicid);
@@ -78,7 +77,6 @@ struct genapic {
 	.probe = aprobe, \
 	.int_delivery_mode = INT_DELIVERY_MODE, \
 	.int_dest_mode = INT_DEST_MODE, \
-	.apic_broadcast_id = APIC_BROADCAST_ID, \
 	.no_balance_irq = NO_BALANCE_IRQ, \
 	.no_ioapic_check = NO_IOAPIC_CHECK, \
 	.ESR_DISABLE = esr_disable, \

include/asm-i386/mach-bigsmp/mach_apic.h

@@ -39,7 +39,6 @@ static inline cpumask_t target_cpus(void)
 #define INT_DELIVERY_MODE dest_Fixed
 #define INT_DEST_MODE 1     /* logical delivery broadcast to all procs */
 
-#define APIC_BROADCAST_ID     (0xff)
 static inline unsigned long check_apicid_used(physid_mask_t bitmap, int apicid)
 {
 	return 0;

include/asm-i386/mach-bigsmp/mach_mpspec.h

 #ifndef __ASM_MACH_MPSPEC_H
 #define __ASM_MACH_MPSPEC_H
 
-/*
- * a maximum of 16 APICs with the current APIC ID architecture.
- */
-#define MAX_APICS 16
-
 #define MAX_IRQ_SOURCES 256
 
 #define MAX_MP_BUSSES 32

include/asm-i386/mach-default/mach_apic.h

@@ -23,12 +23,6 @@ static inline cpumask_const_t target_cpus(void)
 #define INT_DELIVERY_MODE dest_LowestPrio
 #define INT_DEST_MODE 1     /* logical delivery broadcast to all procs */
 
-/*
- * this isn't really broadcast, just a (potentially inaccurate) upper
- * bound for valid physical APIC id's
- */
-#define APIC_BROADCAST_ID      0x0F
-
 static inline unsigned long check_apicid_used(physid_mask_t bitmap, int apicid)
 {
 	return physid_isset(apicid, bitmap);

include/asm-i386/mach-default/mach_mpspec.h

 #ifndef __ASM_MACH_MPSPEC_H
 #define __ASM_MACH_MPSPEC_H
 
-/*
- * a maximum of 16 APICs with the current APIC ID architecture.
- */
-#define MAX_APICS 16
-
 #define MAX_IRQ_SOURCES 256
 
 #define MAX_MP_BUSSES 32

include/asm-i386/mach-es7000/mach_apic.h

@@ -38,7 +38,6 @@ static inline cpumask_t target_cpus(void)
 #define WAKE_SECONDARY_VIA_INIT
 #endif
 
-#define APIC_BROADCAST_ID	(0xff)
 #define NO_IOAPIC_CHECK (1)
 
 static inline unsigned long check_apicid_used(physid_mask_t bitmap, int apicid)

include/asm-i386/mach-es7000/mach_mpspec.h

 #ifndef __ASM_MACH_MPSPEC_H
 #define __ASM_MACH_MPSPEC_H
 
-/*
- * a maximum of 256 APICs with the current APIC ID architecture.
- */
-#define MAX_APICS 256
-
 #define MAX_IRQ_SOURCES 256
 
 #define MAX_MP_BUSSES 32

include/asm-i386/mach-generic/mach_apic.h

@@ -6,7 +6,6 @@
 #define esr_disable (genapic->ESR_DISABLE)
 #define NO_BALANCE_IRQ (genapic->no_balance_irq)
 #define NO_IOAPIC_CHECK	(genapic->no_ioapic_check)
-#define APIC_BROADCAST_ID (genapic->apic_broadcast_id)
 #define INT_DELIVERY_MODE (genapic->int_delivery_mode)
 #define INT_DEST_MODE (genapic->int_dest_mode)
 #undef APIC_DEST_LOGICAL

include/asm-i386/mach-generic/mach_mpspec.h

 #ifndef __ASM_MACH_MPSPEC_H
 #define __ASM_MACH_MPSPEC_H
 
-/*
- * a maximum of 256 APICs with the current APIC ID architecture.
- */
-#define MAX_APICS 256
-
 #define MAX_IRQ_SOURCES 256
 
 /* Summit or generic (i.e. installer) kernels need lots of bus entries. */

include/asm-i386/mach-numaq/mach_apic.h

@@ -22,7 +22,6 @@ static inline cpumask_t target_cpus(void)
 #define INT_DELIVERY_MODE dest_LowestPrio
 #define INT_DEST_MODE 0     /* physical delivery on LOCAL quad */
  
-#define APIC_BROADCAST_ID      0x0F
 #define check_apicid_used(bitmap, apicid) physid_isset(apicid, bitmap)
 #define check_apicid_present(bit) physid_isset(bit, phys_cpu_present_map)
 #define apicid_cluster(apicid) (apicid & 0xF0)

include/asm-i386/mach-numaq/mach_mpspec.h

 #ifndef __ASM_MACH_MPSPEC_H
 #define __ASM_MACH_MPSPEC_H
 
-/*
- * a maximum of 256 APICs with the current APIC ID architecture.
- */
-#define MAX_APICS 256
-
 #define MAX_IRQ_SOURCES 512
 
 #define MAX_MP_BUSSES 32

include/asm-i386/mach-summit/mach_apic.h

@@ -27,7 +27,6 @@ static inline cpumask_t target_cpus(void)
 #define INT_DELIVERY_MODE (dest_Fixed)
 #define INT_DEST_MODE 1     /* logical delivery broadcast to all procs */
 
-#define APIC_BROADCAST_ID     (0xFF)
 static inline unsigned long check_apicid_used(physid_mask_t bitmap, int apicid)
 {
 	return 0;

include/asm-i386/mach-summit/mach_mpspec.h

 #ifndef __ASM_MACH_MPSPEC_H
 #define __ASM_MACH_MPSPEC_H
 
-/*
- * a maximum of 256 APICs with the current APIC ID architecture.
- */
-#define MAX_APICS 256
-
 #define MAX_IRQ_SOURCES 256
 
 /* Maximum 256 PCI busses, plus 1 ISA bus in each of 4 cabinets. */

include/asm-i386/mach-visws/mach_apic.h

@@ -19,7 +19,6 @@
  #define TARGET_CPUS cpumask_of_cpu(0)
 #endif
 
-#define APIC_BROADCAST_ID      0x0F
 #define check_apicid_used(bitmap, apicid)	physid_isset(apicid, bitmap)
 #define check_apicid_present(bit)		physid_isset(bit, phys_cpu_present_map)
 

include/asm-i386/mpspec_def.h

@@ -14,6 +14,7 @@
 #define SMP_MAGIC_IDENT	(('_'<<24)|('P'<<16)|('M'<<8)|'_')
 
 #define MAX_MPC_ENTRY 1024
+#define MAX_APICS      256
 
 struct intel_mp_floating
 {