alistair23-linux/drivers/acpi/tables.c
Fenghua Yu 369d913b24 ACPI: Harden acpi_table_parse_entries() against BIOS bug
Parsing acpi table entries may fall into an infinite loop on a buggy BIOS
which has entry length=0 in acpi table.

Instead of kernel hang with few failure clue which leads to heavy lifting debug
effort, this patch hardens kernel boot by booting into non NUMA mode. The debug
info left in log buffer helps people identify the issue.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2012-10-06 15:51:49 -04:00

374 lines
10 KiB
C

/*
* acpi_tables.c - ACPI Boot-Time Table Parsing
*
* Copyright (C) 2001 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/smp.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/irq.h>
#include <linux/errno.h>
#include <linux/acpi.h>
#include <linux/bootmem.h>
#define PREFIX "ACPI: "
#define ACPI_MAX_TABLES 128
static char *mps_inti_flags_polarity[] = { "dfl", "high", "res", "low" };
static char *mps_inti_flags_trigger[] = { "dfl", "edge", "res", "level" };
static struct acpi_table_desc initial_tables[ACPI_MAX_TABLES] __initdata;
static int acpi_apic_instance __initdata;
void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
{
if (!header)
return;
switch (header->type) {
case ACPI_MADT_TYPE_LOCAL_APIC:
{
struct acpi_madt_local_apic *p =
(struct acpi_madt_local_apic *)header;
printk(KERN_INFO PREFIX
"LAPIC (acpi_id[0x%02x] lapic_id[0x%02x] %s)\n",
p->processor_id, p->id,
(p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
}
break;
case ACPI_MADT_TYPE_LOCAL_X2APIC:
{
struct acpi_madt_local_x2apic *p =
(struct acpi_madt_local_x2apic *)header;
printk(KERN_INFO PREFIX
"X2APIC (apic_id[0x%02x] uid[0x%02x] %s)\n",
p->local_apic_id, p->uid,
(p->lapic_flags & ACPI_MADT_ENABLED) ?
"enabled" : "disabled");
}
break;
case ACPI_MADT_TYPE_IO_APIC:
{
struct acpi_madt_io_apic *p =
(struct acpi_madt_io_apic *)header;
printk(KERN_INFO PREFIX
"IOAPIC (id[0x%02x] address[0x%08x] gsi_base[%d])\n",
p->id, p->address, p->global_irq_base);
}
break;
case ACPI_MADT_TYPE_INTERRUPT_OVERRIDE:
{
struct acpi_madt_interrupt_override *p =
(struct acpi_madt_interrupt_override *)header;
printk(KERN_INFO PREFIX
"INT_SRC_OVR (bus %d bus_irq %d global_irq %d %s %s)\n",
p->bus, p->source_irq, p->global_irq,
mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2]);
if (p->inti_flags &
~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK))
printk(KERN_INFO PREFIX
"INT_SRC_OVR unexpected reserved flags: 0x%x\n",
p->inti_flags &
~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK));
}
break;
case ACPI_MADT_TYPE_NMI_SOURCE:
{
struct acpi_madt_nmi_source *p =
(struct acpi_madt_nmi_source *)header;
printk(KERN_INFO PREFIX
"NMI_SRC (%s %s global_irq %d)\n",
mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
p->global_irq);
}
break;
case ACPI_MADT_TYPE_LOCAL_APIC_NMI:
{
struct acpi_madt_local_apic_nmi *p =
(struct acpi_madt_local_apic_nmi *)header;
printk(KERN_INFO PREFIX
"LAPIC_NMI (acpi_id[0x%02x] %s %s lint[0x%x])\n",
p->processor_id,
mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK ],
mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
p->lint);
}
break;
case ACPI_MADT_TYPE_LOCAL_X2APIC_NMI:
{
u16 polarity, trigger;
struct acpi_madt_local_x2apic_nmi *p =
(struct acpi_madt_local_x2apic_nmi *)header;
polarity = p->inti_flags & ACPI_MADT_POLARITY_MASK;
trigger = (p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2;
printk(KERN_INFO PREFIX
"X2APIC_NMI (uid[0x%02x] %s %s lint[0x%x])\n",
p->uid,
mps_inti_flags_polarity[polarity],
mps_inti_flags_trigger[trigger],
p->lint);
}
break;
case ACPI_MADT_TYPE_LOCAL_APIC_OVERRIDE:
{
struct acpi_madt_local_apic_override *p =
(struct acpi_madt_local_apic_override *)header;
printk(KERN_INFO PREFIX
"LAPIC_ADDR_OVR (address[%p])\n",
(void *)(unsigned long)p->address);
}
break;
case ACPI_MADT_TYPE_IO_SAPIC:
{
struct acpi_madt_io_sapic *p =
(struct acpi_madt_io_sapic *)header;
printk(KERN_INFO PREFIX
"IOSAPIC (id[0x%x] address[%p] gsi_base[%d])\n",
p->id, (void *)(unsigned long)p->address,
p->global_irq_base);
}
break;
case ACPI_MADT_TYPE_LOCAL_SAPIC:
{
struct acpi_madt_local_sapic *p =
(struct acpi_madt_local_sapic *)header;
printk(KERN_INFO PREFIX
"LSAPIC (acpi_id[0x%02x] lsapic_id[0x%02x] lsapic_eid[0x%02x] %s)\n",
p->processor_id, p->id, p->eid,
(p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
}
break;
case ACPI_MADT_TYPE_INTERRUPT_SOURCE:
{
struct acpi_madt_interrupt_source *p =
(struct acpi_madt_interrupt_source *)header;
printk(KERN_INFO PREFIX
"PLAT_INT_SRC (%s %s type[0x%x] id[0x%04x] eid[0x%x] iosapic_vector[0x%x] global_irq[0x%x]\n",
mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
p->type, p->id, p->eid, p->io_sapic_vector,
p->global_irq);
}
break;
default:
printk(KERN_WARNING PREFIX
"Found unsupported MADT entry (type = 0x%x)\n",
header->type);
break;
}
}
int __init
acpi_table_parse_entries(char *id,
unsigned long table_size,
int entry_id,
acpi_table_entry_handler handler,
unsigned int max_entries)
{
struct acpi_table_header *table_header = NULL;
struct acpi_subtable_header *entry;
unsigned int count = 0;
unsigned long table_end;
acpi_size tbl_size;
if (acpi_disabled)
return -ENODEV;
if (!handler)
return -EINVAL;
if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
acpi_get_table_with_size(id, acpi_apic_instance, &table_header, &tbl_size);
else
acpi_get_table_with_size(id, 0, &table_header, &tbl_size);
if (!table_header) {
printk(KERN_WARNING PREFIX "%4.4s not present\n", id);
return -ENODEV;
}
table_end = (unsigned long)table_header + table_header->length;
/* Parse all entries looking for a match. */
entry = (struct acpi_subtable_header *)
((unsigned long)table_header + table_size);
while (((unsigned long)entry) + sizeof(struct acpi_subtable_header) <
table_end) {
if (entry->type == entry_id
&& (!max_entries || count++ < max_entries))
if (handler(entry, table_end))
goto err;
/*
* If entry->length is 0, break from this loop to avoid
* infinite loop.
*/
if (entry->length == 0) {
pr_err(PREFIX "[%4.4s:0x%02x] Invalid zero length\n", id, entry_id);
goto err;
}
entry = (struct acpi_subtable_header *)
((unsigned long)entry + entry->length);
}
if (max_entries && count > max_entries) {
printk(KERN_WARNING PREFIX "[%4.4s:0x%02x] ignored %i entries of "
"%i found\n", id, entry_id, count - max_entries, count);
}
early_acpi_os_unmap_memory((char *)table_header, tbl_size);
return count;
err:
early_acpi_os_unmap_memory((char *)table_header, tbl_size);
return -EINVAL;
}
int __init
acpi_table_parse_madt(enum acpi_madt_type id,
acpi_table_entry_handler handler, unsigned int max_entries)
{
return acpi_table_parse_entries(ACPI_SIG_MADT,
sizeof(struct acpi_table_madt), id,
handler, max_entries);
}
/**
* acpi_table_parse - find table with @id, run @handler on it
*
* @id: table id to find
* @handler: handler to run
*
* Scan the ACPI System Descriptor Table (STD) for a table matching @id,
* run @handler on it. Return 0 if table found, return on if not.
*/
int __init acpi_table_parse(char *id, acpi_table_handler handler)
{
struct acpi_table_header *table = NULL;
acpi_size tbl_size;
if (acpi_disabled)
return -ENODEV;
if (!handler)
return -EINVAL;
if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
acpi_get_table_with_size(id, acpi_apic_instance, &table, &tbl_size);
else
acpi_get_table_with_size(id, 0, &table, &tbl_size);
if (table) {
handler(table);
early_acpi_os_unmap_memory(table, tbl_size);
return 0;
} else
return 1;
}
/*
* The BIOS is supposed to supply a single APIC/MADT,
* but some report two. Provide a knob to use either.
* (don't you wish instance 0 and 1 were not the same?)
*/
static void __init check_multiple_madt(void)
{
struct acpi_table_header *table = NULL;
acpi_size tbl_size;
acpi_get_table_with_size(ACPI_SIG_MADT, 2, &table, &tbl_size);
if (table) {
printk(KERN_WARNING PREFIX
"BIOS bug: multiple APIC/MADT found,"
" using %d\n", acpi_apic_instance);
printk(KERN_WARNING PREFIX
"If \"acpi_apic_instance=%d\" works better, "
"notify linux-acpi@vger.kernel.org\n",
acpi_apic_instance ? 0 : 2);
early_acpi_os_unmap_memory(table, tbl_size);
} else
acpi_apic_instance = 0;
return;
}
/*
* acpi_table_init()
*
* find RSDP, find and checksum SDT/XSDT.
* checksum all tables, print SDT/XSDT
*
* result: sdt_entry[] is initialized
*/
int __init acpi_table_init(void)
{
acpi_status status;
status = acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
if (ACPI_FAILURE(status))
return 1;
check_multiple_madt();
return 0;
}
static int __init acpi_parse_apic_instance(char *str)
{
if (!str)
return -EINVAL;
acpi_apic_instance = simple_strtoul(str, NULL, 0);
printk(KERN_NOTICE PREFIX "Shall use APIC/MADT table %d\n",
acpi_apic_instance);
return 0;
}
early_param("acpi_apic_instance", acpi_parse_apic_instance);