kernel-ark/drivers/firmware/dmi_scan.c
Parag Warudkar 79da472111 x86: fix DMI out of memory problems
People with HP Desktops (including me) encounter couple of DMI errors
during boot - dmi_save_oem_strings_devices: out of memory and
dmi_string: out of memory.

On some HP desktops the DMI data include OEM strings (type 11) out of
which only few are meaningful and most other are empty. DMI code
religiously creates copies of these 27 strings (65 bytes each in my
case) and goes OOM in dmi_string().

If DMI_MAX_DATA is bumped up a little then it goes and fails in
dmi_save_oem_strings while allocating dmi_devices of sizeof(struct
dmi_device) corresponding to these strings.

On x86_64 since we cannot use alloc_bootmem this early, the code uses a
static array of 2048 bytes (DMI_MAX_DATA) for allocating the memory DMI
needs. It does not survive the creation of empty strings and devices.

Fix this by detecting and not newly allocating empty strings and instead
using a one statically defined dmi_empty_string.

Also do not create a new struct dmi_device for each empty string - use
one statically define dmi_device with .name=dmi_empty_string and add
that to the dmi_devices list.

On x64 this should stop the OOM with same current size of DMI_MAX_DATA
and on x86 this should save a good amount of (27*65 bytes +
27*sizeof(struct dmi_device) bootmem.

Compile and boot tested on both 32-bit and 64-bit x86.

Signed-off-by: Parag Warudkar <parag.warudkar@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:31:59 +01:00

499 lines
11 KiB
C

#include <linux/types.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/dmi.h>
#include <linux/efi.h>
#include <linux/bootmem.h>
#include <linux/slab.h>
#include <asm/dmi.h>
static char dmi_empty_string[] = " ";
static char * __init dmi_string(const struct dmi_header *dm, u8 s)
{
const u8 *bp = ((u8 *) dm) + dm->length;
char *str = "";
if (s) {
s--;
while (s > 0 && *bp) {
bp += strlen(bp) + 1;
s--;
}
if (*bp != 0) {
size_t len = strlen(bp)+1;
size_t cmp_len = len > 8 ? 8 : len;
if (!memcmp(bp, dmi_empty_string, cmp_len))
return dmi_empty_string;
str = dmi_alloc(len);
if (str != NULL)
strcpy(str, bp);
else
printk(KERN_ERR "dmi_string: cannot allocate %Zu bytes.\n", len);
}
}
return str;
}
/*
* We have to be cautious here. We have seen BIOSes with DMI pointers
* pointing to completely the wrong place for example
*/
static int __init dmi_table(u32 base, int len, int num,
void (*decode)(const struct dmi_header *))
{
u8 *buf, *data;
int i = 0;
buf = dmi_ioremap(base, len);
if (buf == NULL)
return -1;
data = buf;
/*
* Stop when we see all the items the table claimed to have
* OR we run off the end of the table (also happens)
*/
while ((i < num) && (data - buf + sizeof(struct dmi_header)) <= len) {
const struct dmi_header *dm = (const struct dmi_header *)data;
/*
* We want to know the total length (formated area and strings)
* before decoding to make sure we won't run off the table in
* dmi_decode or dmi_string
*/
data += dm->length;
while ((data - buf < len - 1) && (data[0] || data[1]))
data++;
if (data - buf < len - 1)
decode(dm);
data += 2;
i++;
}
dmi_iounmap(buf, len);
return 0;
}
static int __init dmi_checksum(const u8 *buf)
{
u8 sum = 0;
int a;
for (a = 0; a < 15; a++)
sum += buf[a];
return sum == 0;
}
static char *dmi_ident[DMI_STRING_MAX];
static LIST_HEAD(dmi_devices);
int dmi_available;
/*
* Save a DMI string
*/
static void __init dmi_save_ident(const struct dmi_header *dm, int slot, int string)
{
const char *d = (const char*) dm;
char *p;
if (dmi_ident[slot])
return;
p = dmi_string(dm, d[string]);
if (p == NULL)
return;
dmi_ident[slot] = p;
}
static void __init dmi_save_uuid(const struct dmi_header *dm, int slot, int index)
{
const u8 *d = (u8*) dm + index;
char *s;
int is_ff = 1, is_00 = 1, i;
if (dmi_ident[slot])
return;
for (i = 0; i < 16 && (is_ff || is_00); i++) {
if(d[i] != 0x00) is_ff = 0;
if(d[i] != 0xFF) is_00 = 0;
}
if (is_ff || is_00)
return;
s = dmi_alloc(16*2+4+1);
if (!s)
return;
sprintf(s,
"%02X%02X%02X%02X-%02X%02X-%02X%02X-%02X%02X-%02X%02X%02X%02X%02X%02X",
d[0], d[1], d[2], d[3], d[4], d[5], d[6], d[7],
d[8], d[9], d[10], d[11], d[12], d[13], d[14], d[15]);
dmi_ident[slot] = s;
}
static void __init dmi_save_type(const struct dmi_header *dm, int slot, int index)
{
const u8 *d = (u8*) dm + index;
char *s;
if (dmi_ident[slot])
return;
s = dmi_alloc(4);
if (!s)
return;
sprintf(s, "%u", *d & 0x7F);
dmi_ident[slot] = s;
}
static void __init dmi_save_devices(const struct dmi_header *dm)
{
int i, count = (dm->length - sizeof(struct dmi_header)) / 2;
struct dmi_device *dev;
for (i = 0; i < count; i++) {
const char *d = (char *)(dm + 1) + (i * 2);
/* Skip disabled device */
if ((*d & 0x80) == 0)
continue;
dev = dmi_alloc(sizeof(*dev));
if (!dev) {
printk(KERN_ERR "dmi_save_devices: out of memory.\n");
break;
}
dev->type = *d++ & 0x7f;
dev->name = dmi_string(dm, *d);
dev->device_data = NULL;
list_add(&dev->list, &dmi_devices);
}
}
static struct dmi_device empty_oem_string_dev = {
.name = dmi_empty_string,
};
static void __init dmi_save_oem_strings_devices(const struct dmi_header *dm)
{
int i, count = *(u8 *)(dm + 1);
struct dmi_device *dev;
for (i = 1; i <= count; i++) {
char *devname = dmi_string(dm, i);
if (!strcmp(devname, dmi_empty_string)) {
list_add(&empty_oem_string_dev.list, &dmi_devices);
continue;
}
dev = dmi_alloc(sizeof(*dev));
if (!dev) {
printk(KERN_ERR
"dmi_save_oem_strings_devices: out of memory.\n");
break;
}
dev->type = DMI_DEV_TYPE_OEM_STRING;
dev->name = devname;
dev->device_data = NULL;
list_add(&dev->list, &dmi_devices);
}
}
static void __init dmi_save_ipmi_device(const struct dmi_header *dm)
{
struct dmi_device *dev;
void * data;
data = dmi_alloc(dm->length);
if (data == NULL) {
printk(KERN_ERR "dmi_save_ipmi_device: out of memory.\n");
return;
}
memcpy(data, dm, dm->length);
dev = dmi_alloc(sizeof(*dev));
if (!dev) {
printk(KERN_ERR "dmi_save_ipmi_device: out of memory.\n");
return;
}
dev->type = DMI_DEV_TYPE_IPMI;
dev->name = "IPMI controller";
dev->device_data = data;
list_add(&dev->list, &dmi_devices);
}
/*
* Process a DMI table entry. Right now all we care about are the BIOS
* and machine entries. For 2.5 we should pull the smbus controller info
* out of here.
*/
static void __init dmi_decode(const struct dmi_header *dm)
{
switch(dm->type) {
case 0: /* BIOS Information */
dmi_save_ident(dm, DMI_BIOS_VENDOR, 4);
dmi_save_ident(dm, DMI_BIOS_VERSION, 5);
dmi_save_ident(dm, DMI_BIOS_DATE, 8);
break;
case 1: /* System Information */
dmi_save_ident(dm, DMI_SYS_VENDOR, 4);
dmi_save_ident(dm, DMI_PRODUCT_NAME, 5);
dmi_save_ident(dm, DMI_PRODUCT_VERSION, 6);
dmi_save_ident(dm, DMI_PRODUCT_SERIAL, 7);
dmi_save_uuid(dm, DMI_PRODUCT_UUID, 8);
break;
case 2: /* Base Board Information */
dmi_save_ident(dm, DMI_BOARD_VENDOR, 4);
dmi_save_ident(dm, DMI_BOARD_NAME, 5);
dmi_save_ident(dm, DMI_BOARD_VERSION, 6);
dmi_save_ident(dm, DMI_BOARD_SERIAL, 7);
dmi_save_ident(dm, DMI_BOARD_ASSET_TAG, 8);
break;
case 3: /* Chassis Information */
dmi_save_ident(dm, DMI_CHASSIS_VENDOR, 4);
dmi_save_type(dm, DMI_CHASSIS_TYPE, 5);
dmi_save_ident(dm, DMI_CHASSIS_VERSION, 6);
dmi_save_ident(dm, DMI_CHASSIS_SERIAL, 7);
dmi_save_ident(dm, DMI_CHASSIS_ASSET_TAG, 8);
break;
case 10: /* Onboard Devices Information */
dmi_save_devices(dm);
break;
case 11: /* OEM Strings */
dmi_save_oem_strings_devices(dm);
break;
case 38: /* IPMI Device Information */
dmi_save_ipmi_device(dm);
}
}
static int __init dmi_present(const char __iomem *p)
{
u8 buf[15];
memcpy_fromio(buf, p, 15);
if ((memcmp(buf, "_DMI_", 5) == 0) && dmi_checksum(buf)) {
u16 num = (buf[13] << 8) | buf[12];
u16 len = (buf[7] << 8) | buf[6];
u32 base = (buf[11] << 24) | (buf[10] << 16) |
(buf[9] << 8) | buf[8];
/*
* DMI version 0.0 means that the real version is taken from
* the SMBIOS version, which we don't know at this point.
*/
if (buf[14] != 0)
printk(KERN_INFO "DMI %d.%d present.\n",
buf[14] >> 4, buf[14] & 0xF);
else
printk(KERN_INFO "DMI present.\n");
if (dmi_table(base,len, num, dmi_decode) == 0)
return 0;
}
return 1;
}
void __init dmi_scan_machine(void)
{
char __iomem *p, *q;
int rc;
if (efi_enabled) {
if (efi.smbios == EFI_INVALID_TABLE_ADDR)
goto out;
/* This is called as a core_initcall() because it isn't
* needed during early boot. This also means we can
* iounmap the space when we're done with it.
*/
p = dmi_ioremap(efi.smbios, 32);
if (p == NULL)
goto out;
rc = dmi_present(p + 0x10); /* offset of _DMI_ string */
dmi_iounmap(p, 32);
if (!rc) {
dmi_available = 1;
return;
}
}
else {
/*
* no iounmap() for that ioremap(); it would be a no-op, but
* it's so early in setup that sucker gets confused into doing
* what it shouldn't if we actually call it.
*/
p = dmi_ioremap(0xF0000, 0x10000);
if (p == NULL)
goto out;
for (q = p; q < p + 0x10000; q += 16) {
rc = dmi_present(q);
if (!rc) {
dmi_available = 1;
return;
}
}
}
out: printk(KERN_INFO "DMI not present or invalid.\n");
}
/**
* dmi_check_system - check system DMI data
* @list: array of dmi_system_id structures to match against
* All non-null elements of the list must match
* their slot's (field index's) data (i.e., each
* list string must be a substring of the specified
* DMI slot's string data) to be considered a
* successful match.
*
* Walk the blacklist table running matching functions until someone
* returns non zero or we hit the end. Callback function is called for
* each successful match. Returns the number of matches.
*/
int dmi_check_system(const struct dmi_system_id *list)
{
int i, count = 0;
const struct dmi_system_id *d = list;
while (d->ident) {
for (i = 0; i < ARRAY_SIZE(d->matches); i++) {
int s = d->matches[i].slot;
if (s == DMI_NONE)
continue;
if (dmi_ident[s] && strstr(dmi_ident[s], d->matches[i].substr))
continue;
/* No match */
goto fail;
}
count++;
if (d->callback && d->callback(d))
break;
fail: d++;
}
return count;
}
EXPORT_SYMBOL(dmi_check_system);
/**
* dmi_get_system_info - return DMI data value
* @field: data index (see enum dmi_field)
*
* Returns one DMI data value, can be used to perform
* complex DMI data checks.
*/
const char *dmi_get_system_info(int field)
{
return dmi_ident[field];
}
EXPORT_SYMBOL(dmi_get_system_info);
/**
* dmi_name_in_vendors - Check if string is anywhere in the DMI vendor information.
* @str: Case sensitive Name
*/
int dmi_name_in_vendors(const char *str)
{
static int fields[] = { DMI_BIOS_VENDOR, DMI_BIOS_VERSION, DMI_SYS_VENDOR,
DMI_PRODUCT_NAME, DMI_PRODUCT_VERSION, DMI_BOARD_VENDOR,
DMI_BOARD_NAME, DMI_BOARD_VERSION, DMI_NONE };
int i;
for (i = 0; fields[i] != DMI_NONE; i++) {
int f = fields[i];
if (dmi_ident[f] && strstr(dmi_ident[f], str))
return 1;
}
return 0;
}
EXPORT_SYMBOL(dmi_name_in_vendors);
/**
* dmi_find_device - find onboard device by type/name
* @type: device type or %DMI_DEV_TYPE_ANY to match all device types
* @name: device name string or %NULL to match all
* @from: previous device found in search, or %NULL for new search.
*
* Iterates through the list of known onboard devices. If a device is
* found with a matching @vendor and @device, a pointer to its device
* structure is returned. Otherwise, %NULL is returned.
* A new search is initiated by passing %NULL as the @from argument.
* If @from is not %NULL, searches continue from next device.
*/
const struct dmi_device * dmi_find_device(int type, const char *name,
const struct dmi_device *from)
{
const struct list_head *head = from ? &from->list : &dmi_devices;
struct list_head *d;
for(d = head->next; d != &dmi_devices; d = d->next) {
const struct dmi_device *dev =
list_entry(d, struct dmi_device, list);
if (((type == DMI_DEV_TYPE_ANY) || (dev->type == type)) &&
((name == NULL) || (strcmp(dev->name, name) == 0)))
return dev;
}
return NULL;
}
EXPORT_SYMBOL(dmi_find_device);
/**
* dmi_get_year - Return year of a DMI date
* @field: data index (like dmi_get_system_info)
*
* Returns -1 when the field doesn't exist. 0 when it is broken.
*/
int dmi_get_year(int field)
{
int year;
const char *s = dmi_get_system_info(field);
if (!s)
return -1;
if (*s == '\0')
return 0;
s = strrchr(s, '/');
if (!s)
return 0;
s += 1;
year = simple_strtoul(s, NULL, 0);
if (year && year < 100) { /* 2-digit year */
year += 1900;
if (year < 1996) /* no dates < spec 1.0 */
year += 100;
}
return year;
}
/**
* dmi_get_slot - return dmi_ident[slot]
* @slot: index into dmi_ident[]
*/
char *dmi_get_slot(int slot)
{
return(dmi_ident[slot]);
}