mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-04 09:59:32 +00:00
![Yinghai Lu](/assets/img/avatar_default.png)
1. replace find_e820_area with memblock_find_in_range 2. replace reserve_early with memblock_x86_reserve_range 3. replace free_early with memblock_x86_free_range. 4. NO_BOOTMEM will switch to use memblock too. 5. use _e820, _early wrap in the patch, in following patch, will replace them all 6. because memblock_x86_free_range support partial free, we can remove some special care 7. Need to make sure that memblock_find_in_range() is called after memblock_x86_fill() so adjust some calling later in setup.c::setup_arch() -- corruption_check and mptable_update -v2: Move reserve_brk() early Before fill_memblock_area, to avoid overlap between brk and memblock_find_in_range() that could happen We have more then 128 RAM entry in E820 tables, and memblock_x86_fill() could use memblock_find_in_range() to find a new place for memblock.memory.region array. and We don't need to use extend_brk() after fill_memblock_area() So move reserve_brk() early before fill_memblock_area(). -v3: Move find_smp_config early To make sure memblock_find_in_range not find wrong place, if BIOS doesn't put mptable in right place. -v4: Treat RESERVED_KERN as RAM in memblock.memory. and they are already in memblock.reserved already.. use __NOT_KEEP_MEMBLOCK to make sure memblock related code could be freed later. -v5: Generic version __memblock_find_in_range() is going from high to low, and for 32bit active_region for 32bit does include high pages need to replace the limit with memblock.default_alloc_limit, aka get_max_mapped() -v6: Use current_limit instead -v7: check with MEMBLOCK_ERROR instead of -1ULL or -1L -v8: Set memblock_can_resize early to handle EFI with more RAM entries -v9: update after kmemleak changes in mainline Suggested-by: David S. Miller <davem@davemloft.net> Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
163 lines
3.8 KiB
C
163 lines
3.8 KiB
C
#include <linux/module.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/kthread.h>
|
|
#include <linux/workqueue.h>
|
|
#include <linux/memblock.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.
|
|
*/
|
|
#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 scan_area {
|
|
u64 addr;
|
|
u64 size;
|
|
} scan_areas[MAX_SCAN_AREAS];
|
|
static int num_scan_areas;
|
|
|
|
static __init 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 __init 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 __init 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 = memblock_x86_find_in_range_size(addr, &size, PAGE_SIZE);
|
|
|
|
if (addr == MEMBLOCK_ERROR)
|
|
break;
|
|
|
|
if (addr >= corruption_check_size)
|
|
break;
|
|
|
|
if ((addr + size) > corruption_check_size)
|
|
size = corruption_check_size - addr;
|
|
|
|
memblock_x86_reserve_range(addr, addr + size, "SCAN RAM");
|
|
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);
|
|
}
|
|
|
|
|
|
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_ONCE(corruption, KERN_ERR "Memory corruption detected in low memory\n");
|
|
}
|
|
|
|
static void check_corruption(struct work_struct *dummy);
|
|
static DECLARE_DELAYED_WORK(bios_check_work, check_corruption);
|
|
|
|
static void check_corruption(struct work_struct *dummy)
|
|
{
|
|
check_for_bios_corruption();
|
|
schedule_delayed_work(&bios_check_work,
|
|
round_jiffies_relative(corruption_check_period*HZ));
|
|
}
|
|
|
|
static int start_periodic_check_for_corruption(void)
|
|
{
|
|
if (!memory_corruption_check || corruption_check_period == 0)
|
|
return 0;
|
|
|
|
printk(KERN_INFO "Scanning for low memory corruption every %d seconds\n",
|
|
corruption_check_period);
|
|
|
|
/* First time we run the checks right away */
|
|
schedule_delayed_work(&bios_check_work, 0);
|
|
return 0;
|
|
}
|
|
|
|
module_init(start_periodic_check_for_corruption);
|
|
|