Commit 6784f7d0 authored by Arjan van de Ven's avatar Arjan van de Ven Committed by Ingo Molnar
Browse files

x86: corruption check: move the corruption checks into their own file 



Impact: cleanup

The corruption check code is rather sizable and it's likely to grow over
time when we add checks for more types of corruptions (there's a few
candidates in kerneloops.org that I want to add checks for)... so lets move
it to its own file

Signed-off-by: default avatarArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 04d2aac3

arch/x86/include/asm/setup.h

+4 −0
Original line number Diff line number Diff line
@@ -8,6 +8,10 @@ 
/* Interrupt control for vSMPowered x86_64 systems */

void vsmp_init(void);





void setup_bios_corruption_check(void);





#ifdef CONFIG_X86_VISWS

extern void visws_early_detect(void);

extern int is_visws_box(void);

arch/x86/kernel/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -35,6 +35,7 @@ obj-y += bootflag.o e820.o 
obj-y			+= pci-dma.o quirks.o i8237.o topology.o kdebugfs.o

obj-y			+= alternative.o i8253.o pci-nommu.o

obj-y			+= tsc.o io_delay.o rtc.o

obj-y			+= check.o



obj-$(CONFIG_X86_TRAMPOLINE)	+= trampoline.o

obj-y				+= process.o

arch/x86/kernel/check.c

0 → 100644
+158 −0
Original line number Diff line number Diff line 
#include <linux/module.h>

#include <linux/sched.h>



#include <asm/e820.h>

#include <asm/proto.h>



/*

 * Some BIOSes seem to corrupt the low 64k of memory during events

 * like suspend/resume and unplugging an HDMI cable.  Reserve all

 * remaining free memory in that area and fill it with a distinct

 * pattern.

 */

#ifdef CONFIG_X86_CHECK_BIOS_CORRUPTION

#define MAX_SCAN_AREAS	8



static int __read_mostly memory_corruption_check = -1;



static unsigned __read_mostly corruption_check_size = 64*1024;

static unsigned __read_mostly corruption_check_period = 60; /* seconds */



static struct e820entry scan_areas[MAX_SCAN_AREAS];

static int num_scan_areas;





static int set_corruption_check(char *arg)

{

	char *end;



	memory_corruption_check = simple_strtol(arg, &end, 10);



	return (*end == 0) ? 0 : -EINVAL;

}

early_param("memory_corruption_check", set_corruption_check);



static int set_corruption_check_period(char *arg)

{

	char *end;



	corruption_check_period = simple_strtoul(arg, &end, 10);



	return (*end == 0) ? 0 : -EINVAL;

}

early_param("memory_corruption_check_period", set_corruption_check_period);



static int set_corruption_check_size(char *arg)

{

	char *end;

	unsigned size;



	size = memparse(arg, &end);



	if (*end == '\0')

		corruption_check_size = size;



	return (size == corruption_check_size) ? 0 : -EINVAL;

}

early_param("memory_corruption_check_size", set_corruption_check_size);





void __init setup_bios_corruption_check(void)

{

	u64 addr = PAGE_SIZE;	/* assume first page is reserved anyway */



	if (memory_corruption_check == -1) {

		memory_corruption_check =

#ifdef CONFIG_X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK

			1

#else

			0

#endif

			;

	}



	if (corruption_check_size == 0)

		memory_corruption_check = 0;



	if (!memory_corruption_check)

		return;



	corruption_check_size = round_up(corruption_check_size, PAGE_SIZE);



	while (addr < corruption_check_size && num_scan_areas < MAX_SCAN_AREAS) {

		u64 size;

		addr = find_e820_area_size(addr, &size, PAGE_SIZE);



		if (addr == 0)

			break;



		if ((addr + size) > corruption_check_size)

			size = corruption_check_size - addr;



		if (size == 0)

			break;



		e820_update_range(addr, size, E820_RAM, E820_RESERVED);

		scan_areas[num_scan_areas].addr = addr;

		scan_areas[num_scan_areas].size = size;

		num_scan_areas++;



		/* Assume we've already mapped this early memory */

		memset(__va(addr), 0, size);



		addr += size;

	}



	printk(KERN_INFO "Scanning %d areas for low memory corruption\n",

	       num_scan_areas);

	update_e820();

}



static struct timer_list periodic_check_timer;



void check_for_bios_corruption(void)

{

	int i;

	int corruption = 0;



	if (!memory_corruption_check)

		return;



	for (i = 0; i < num_scan_areas; i++) {

		unsigned long *addr = __va(scan_areas[i].addr);

		unsigned long size = scan_areas[i].size;



		for (; size; addr++, size -= sizeof(unsigned long)) {

			if (!*addr)

				continue;

			printk(KERN_ERR "Corrupted low memory at %p (%lx phys) = %08lx\n",

			       addr, __pa(addr), *addr);

			corruption = 1;

			*addr = 0;

		}

	}



	WARN(corruption, KERN_ERR "Memory corruption detected in low memory\n");

}



static void periodic_check_for_corruption(unsigned long data)

{

	check_for_bios_corruption();

	mod_timer(&periodic_check_timer,

		round_jiffies(jiffies + corruption_check_period*HZ));

}



void start_periodic_check_for_corruption(void)

{

	if (!memory_corruption_check || corruption_check_period == 0)

		return;



	printk(KERN_INFO "Scanning for low memory corruption every %d seconds\n",

	       corruption_check_period);



	init_timer(&periodic_check_timer);

	periodic_check_timer.function = &periodic_check_for_corruption;

	periodic_check_for_corruption(0);

}

#endif

arch/x86/kernel/setup.c

+0 −152
Original line number Diff line number Diff line
@@ -587,158 +587,6 @@ static struct x86_quirks default_x86_quirks __initdata; 


struct x86_quirks *x86_quirks __initdata = &default_x86_quirks;



/*

 * Some BIOSes seem to corrupt the low 64k of memory during events

 * like suspend/resume and unplugging an HDMI cable.  Reserve all

 * remaining free memory in that area and fill it with a distinct

 * pattern.

 */

#ifdef CONFIG_X86_CHECK_BIOS_CORRUPTION

#define MAX_SCAN_AREAS	8



static int __read_mostly memory_corruption_check = -1;



static unsigned __read_mostly corruption_check_size = 64*1024;

static unsigned __read_mostly corruption_check_period = 60; /* seconds */



static struct e820entry scan_areas[MAX_SCAN_AREAS];

static int num_scan_areas;





static int set_corruption_check(char *arg)

{

	char *end;



	memory_corruption_check = simple_strtol(arg, &end, 10);



	return (*end == 0) ? 0 : -EINVAL;

}

early_param("memory_corruption_check", set_corruption_check);



static int set_corruption_check_period(char *arg)

{

	char *end;



	corruption_check_period = simple_strtoul(arg, &end, 10);



	return (*end == 0) ? 0 : -EINVAL;

}

early_param("memory_corruption_check_period", set_corruption_check_period);



static int set_corruption_check_size(char *arg)

{

	char *end;

	unsigned size;



	size = memparse(arg, &end);



	if (*end == '\0')

		corruption_check_size = size;



	return (size == corruption_check_size) ? 0 : -EINVAL;

}

early_param("memory_corruption_check_size", set_corruption_check_size);





static void __init setup_bios_corruption_check(void)

{

	u64 addr = PAGE_SIZE;	/* assume first page is reserved anyway */



	if (memory_corruption_check == -1) {

		memory_corruption_check =

#ifdef CONFIG_X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK

			1

#else

			0

#endif

			;

	}



	if (corruption_check_size == 0)

		memory_corruption_check = 0;



	if (!memory_corruption_check)

		return;



	corruption_check_size = round_up(corruption_check_size, PAGE_SIZE);



	while (addr < corruption_check_size && num_scan_areas < MAX_SCAN_AREAS) {

		u64 size;

		addr = find_e820_area_size(addr, &size, PAGE_SIZE);



		if (addr == 0)

			break;



		if ((addr + size) > corruption_check_size)

			size = corruption_check_size - addr;



		if (size == 0)

			break;



		e820_update_range(addr, size, E820_RAM, E820_RESERVED);

		scan_areas[num_scan_areas].addr = addr;

		scan_areas[num_scan_areas].size = size;

		num_scan_areas++;



		/* Assume we've already mapped this early memory */

		memset(__va(addr), 0, size);



		addr += size;

	}



	printk(KERN_INFO "Scanning %d areas for low memory corruption\n",

	       num_scan_areas);

	update_e820();

}



static struct timer_list periodic_check_timer;



void check_for_bios_corruption(void)

{

	int i;

	int corruption = 0;



	if (!memory_corruption_check)

		return;



	for (i = 0; i < num_scan_areas; i++) {

		unsigned long *addr = __va(scan_areas[i].addr);

		unsigned long size = scan_areas[i].size;



		for (; size; addr++, size -= sizeof(unsigned long)) {

			if (!*addr)

				continue;

			printk(KERN_ERR "Corrupted low memory at %p (%lx phys) = %08lx\n",

			       addr, __pa(addr), *addr);

			corruption = 1;

			*addr = 0;

		}

	}



	WARN(corruption, KERN_ERR "Memory corruption detected in low memory\n");

}



static void periodic_check_for_corruption(unsigned long data)

{

	check_for_bios_corruption();

	mod_timer(&periodic_check_timer,

		round_jiffies(jiffies + corruption_check_period*HZ));

}



void start_periodic_check_for_corruption(void)

{

	if (!memory_corruption_check || corruption_check_period == 0)

		return;



	printk(KERN_INFO "Scanning for low memory corruption every %d seconds\n",

	       corruption_check_period);



	init_timer(&periodic_check_timer);

	periodic_check_timer.function = &periodic_check_for_corruption;

	periodic_check_for_corruption(0);

}

#endif



static int __init dmi_low_memory_corruption(const struct dmi_system_id *d)

{

	printk(KERN_NOTICE

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