362 строки
9.0 KiB
C
362 строки
9.0 KiB
C
/*
|
|
* Page Deallocation Table (PDT) support
|
|
*
|
|
* The Page Deallocation Table (PDT) is maintained by firmware and holds a
|
|
* list of memory addresses in which memory errors were detected.
|
|
* The list contains both single-bit (correctable) and double-bit
|
|
* (uncorrectable) errors.
|
|
*
|
|
* Copyright 2017 by Helge Deller <deller@gmx.de>
|
|
*
|
|
* possible future enhancements:
|
|
* - add userspace interface via procfs or sysfs to clear PDT
|
|
*/
|
|
|
|
#include <linux/memblock.h>
|
|
#include <linux/seq_file.h>
|
|
#include <linux/kthread.h>
|
|
#include <linux/initrd.h>
|
|
|
|
#include <asm/pdc.h>
|
|
#include <asm/pdcpat.h>
|
|
#include <asm/sections.h>
|
|
#include <asm/pgtable.h>
|
|
|
|
enum pdt_access_type {
|
|
PDT_NONE,
|
|
PDT_PDC,
|
|
PDT_PAT_NEW,
|
|
PDT_PAT_CELL
|
|
};
|
|
|
|
static enum pdt_access_type pdt_type;
|
|
|
|
/* PDT poll interval: 1 minute if errors, 5 minutes if everything OK. */
|
|
#define PDT_POLL_INTERVAL_DEFAULT (5*60*HZ)
|
|
#define PDT_POLL_INTERVAL_SHORT (1*60*HZ)
|
|
static unsigned long pdt_poll_interval = PDT_POLL_INTERVAL_DEFAULT;
|
|
|
|
/* global PDT status information */
|
|
static struct pdc_mem_retinfo pdt_status;
|
|
|
|
#define MAX_PDT_TABLE_SIZE PAGE_SIZE
|
|
#define MAX_PDT_ENTRIES (MAX_PDT_TABLE_SIZE / sizeof(unsigned long))
|
|
static unsigned long pdt_entry[MAX_PDT_ENTRIES] __page_aligned_bss;
|
|
|
|
/*
|
|
* Constants for the pdt_entry format:
|
|
* A pdt_entry holds the physical address in bits 0-57, bits 58-61 are
|
|
* reserved, bit 62 is the perm bit and bit 63 is the error_type bit.
|
|
* The perm bit indicates whether the error have been verified as a permanent
|
|
* error (value of 1) or has not been verified, and may be transient (value
|
|
* of 0). The error_type bit indicates whether the error is a single bit error
|
|
* (value of 1) or a multiple bit error.
|
|
* On non-PAT machines phys_addr is encoded in bits 0-59 and error_type in bit
|
|
* 63. Those machines don't provide the perm bit.
|
|
*/
|
|
|
|
#define PDT_ADDR_PHYS_MASK (pdt_type != PDT_PDC ? ~0x3f : ~0x0f)
|
|
#define PDT_ADDR_PERM_ERR (pdt_type != PDT_PDC ? 2UL : 0UL)
|
|
#define PDT_ADDR_SINGLE_ERR 1UL
|
|
|
|
/* report PDT entries via /proc/meminfo */
|
|
void arch_report_meminfo(struct seq_file *m)
|
|
{
|
|
if (pdt_type == PDT_NONE)
|
|
return;
|
|
|
|
seq_printf(m, "PDT_max_entries: %7lu\n",
|
|
pdt_status.pdt_size);
|
|
seq_printf(m, "PDT_cur_entries: %7lu\n",
|
|
pdt_status.pdt_entries);
|
|
}
|
|
|
|
static int get_info_pat_new(void)
|
|
{
|
|
struct pdc_pat_mem_retinfo pat_rinfo;
|
|
int ret;
|
|
|
|
/* newer PAT machines like C8000 report info for all cells */
|
|
if (is_pdc_pat())
|
|
ret = pdc_pat_mem_pdt_info(&pat_rinfo);
|
|
else
|
|
return PDC_BAD_PROC;
|
|
|
|
pdt_status.pdt_size = pat_rinfo.max_pdt_entries;
|
|
pdt_status.pdt_entries = pat_rinfo.current_pdt_entries;
|
|
pdt_status.pdt_status = 0;
|
|
pdt_status.first_dbe_loc = pat_rinfo.first_dbe_loc;
|
|
pdt_status.good_mem = pat_rinfo.good_mem;
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int get_info_pat_cell(void)
|
|
{
|
|
struct pdc_pat_mem_cell_pdt_retinfo cell_rinfo;
|
|
int ret;
|
|
|
|
/* older PAT machines like rp5470 report cell info only */
|
|
if (is_pdc_pat())
|
|
ret = pdc_pat_mem_pdt_cell_info(&cell_rinfo, parisc_cell_num);
|
|
else
|
|
return PDC_BAD_PROC;
|
|
|
|
pdt_status.pdt_size = cell_rinfo.max_pdt_entries;
|
|
pdt_status.pdt_entries = cell_rinfo.current_pdt_entries;
|
|
pdt_status.pdt_status = 0;
|
|
pdt_status.first_dbe_loc = cell_rinfo.first_dbe_loc;
|
|
pdt_status.good_mem = cell_rinfo.good_mem;
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void report_mem_err(unsigned long pde)
|
|
{
|
|
struct pdc_pat_mem_phys_mem_location loc;
|
|
unsigned long addr;
|
|
char dimm_txt[32];
|
|
|
|
addr = pde & PDT_ADDR_PHYS_MASK;
|
|
|
|
/* show DIMM slot description on PAT machines */
|
|
if (is_pdc_pat()) {
|
|
pdc_pat_mem_get_dimm_phys_location(&loc, addr);
|
|
sprintf(dimm_txt, "DIMM slot %02x, ", loc.dimm_slot);
|
|
} else
|
|
dimm_txt[0] = 0;
|
|
|
|
pr_warn("PDT: BAD MEMORY at 0x%08lx, %s%s%s-bit error.\n",
|
|
addr, dimm_txt,
|
|
pde & PDT_ADDR_PERM_ERR ? "permanent ":"",
|
|
pde & PDT_ADDR_SINGLE_ERR ? "single":"multi");
|
|
}
|
|
|
|
|
|
/*
|
|
* pdc_pdt_init()
|
|
*
|
|
* Initialize kernel PDT structures, read initial PDT table from firmware,
|
|
* report all current PDT entries and mark bad memory with memblock_reserve()
|
|
* to avoid that the kernel will use broken memory areas.
|
|
*
|
|
*/
|
|
void __init pdc_pdt_init(void)
|
|
{
|
|
int ret, i;
|
|
unsigned long entries;
|
|
struct pdc_mem_read_pdt pdt_read_ret;
|
|
|
|
pdt_type = PDT_PAT_NEW;
|
|
ret = get_info_pat_new();
|
|
|
|
if (ret != PDC_OK) {
|
|
pdt_type = PDT_PAT_CELL;
|
|
ret = get_info_pat_cell();
|
|
}
|
|
|
|
if (ret != PDC_OK) {
|
|
pdt_type = PDT_PDC;
|
|
/* non-PAT machines provide the standard PDC call */
|
|
ret = pdc_mem_pdt_info(&pdt_status);
|
|
}
|
|
|
|
if (ret != PDC_OK) {
|
|
pdt_type = PDT_NONE;
|
|
pr_info("PDT: Firmware does not provide any page deallocation"
|
|
" information.\n");
|
|
return;
|
|
}
|
|
|
|
entries = pdt_status.pdt_entries;
|
|
if (WARN_ON(entries > MAX_PDT_ENTRIES))
|
|
entries = pdt_status.pdt_entries = MAX_PDT_ENTRIES;
|
|
|
|
pr_info("PDT: type %s, size %lu, entries %lu, status %lu, dbe_loc 0x%lx,"
|
|
" good_mem %lu MB\n",
|
|
pdt_type == PDT_PDC ? __stringify(PDT_PDC) :
|
|
pdt_type == PDT_PAT_CELL ? __stringify(PDT_PAT_CELL)
|
|
: __stringify(PDT_PAT_NEW),
|
|
pdt_status.pdt_size, pdt_status.pdt_entries,
|
|
pdt_status.pdt_status, pdt_status.first_dbe_loc,
|
|
pdt_status.good_mem / 1024 / 1024);
|
|
|
|
if (entries == 0) {
|
|
pr_info("PDT: Firmware reports all memory OK.\n");
|
|
return;
|
|
}
|
|
|
|
if (pdt_status.first_dbe_loc &&
|
|
pdt_status.first_dbe_loc <= __pa((unsigned long)&_end))
|
|
pr_crit("CRITICAL: Bad memory inside kernel image memory area!\n");
|
|
|
|
pr_warn("PDT: Firmware reports %lu entries of faulty memory:\n",
|
|
entries);
|
|
|
|
if (pdt_type == PDT_PDC)
|
|
ret = pdc_mem_pdt_read_entries(&pdt_read_ret, pdt_entry);
|
|
else {
|
|
#ifdef CONFIG_64BIT
|
|
struct pdc_pat_mem_read_pd_retinfo pat_pret;
|
|
|
|
if (pdt_type == PDT_PAT_CELL)
|
|
ret = pdc_pat_mem_read_cell_pdt(&pat_pret, pdt_entry,
|
|
MAX_PDT_ENTRIES);
|
|
else
|
|
ret = pdc_pat_mem_read_pd_pdt(&pat_pret, pdt_entry,
|
|
MAX_PDT_TABLE_SIZE, 0);
|
|
#else
|
|
ret = PDC_BAD_PROC;
|
|
#endif
|
|
}
|
|
|
|
if (ret != PDC_OK) {
|
|
pdt_type = PDT_NONE;
|
|
pr_warn("PDT: Get PDT entries failed with %d\n", ret);
|
|
return;
|
|
}
|
|
|
|
for (i = 0; i < pdt_status.pdt_entries; i++) {
|
|
unsigned long addr;
|
|
|
|
report_mem_err(pdt_entry[i]);
|
|
|
|
addr = pdt_entry[i] & PDT_ADDR_PHYS_MASK;
|
|
if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) &&
|
|
addr >= initrd_start && addr < initrd_end)
|
|
pr_crit("CRITICAL: initrd possibly broken "
|
|
"due to bad memory!\n");
|
|
|
|
/* mark memory page bad */
|
|
memblock_reserve(pdt_entry[i] & PAGE_MASK, PAGE_SIZE);
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* This is the PDT kernel thread main loop.
|
|
*/
|
|
|
|
static int pdt_mainloop(void *unused)
|
|
{
|
|
struct pdc_mem_read_pdt pdt_read_ret;
|
|
struct pdc_pat_mem_read_pd_retinfo pat_pret __maybe_unused;
|
|
unsigned long old_num_entries;
|
|
unsigned long *bad_mem_ptr;
|
|
int num, ret;
|
|
|
|
for (;;) {
|
|
set_current_state(TASK_INTERRUPTIBLE);
|
|
|
|
old_num_entries = pdt_status.pdt_entries;
|
|
|
|
schedule_timeout(pdt_poll_interval);
|
|
if (kthread_should_stop())
|
|
break;
|
|
|
|
/* Do we have new PDT entries? */
|
|
switch (pdt_type) {
|
|
case PDT_PAT_NEW:
|
|
ret = get_info_pat_new();
|
|
break;
|
|
case PDT_PAT_CELL:
|
|
ret = get_info_pat_cell();
|
|
break;
|
|
default:
|
|
ret = pdc_mem_pdt_info(&pdt_status);
|
|
break;
|
|
}
|
|
|
|
if (ret != PDC_OK) {
|
|
pr_warn("PDT: unexpected failure %d\n", ret);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* if no new PDT entries, just wait again */
|
|
num = pdt_status.pdt_entries - old_num_entries;
|
|
if (num <= 0)
|
|
continue;
|
|
|
|
/* decrease poll interval in case we found memory errors */
|
|
if (pdt_status.pdt_entries &&
|
|
pdt_poll_interval == PDT_POLL_INTERVAL_DEFAULT)
|
|
pdt_poll_interval = PDT_POLL_INTERVAL_SHORT;
|
|
|
|
/* limit entries to get */
|
|
if (num > MAX_PDT_ENTRIES) {
|
|
num = MAX_PDT_ENTRIES;
|
|
pdt_status.pdt_entries = old_num_entries + num;
|
|
}
|
|
|
|
/* get new entries */
|
|
switch (pdt_type) {
|
|
#ifdef CONFIG_64BIT
|
|
case PDT_PAT_CELL:
|
|
if (pdt_status.pdt_entries > MAX_PDT_ENTRIES) {
|
|
pr_crit("PDT: too many entries.\n");
|
|
return -ENOMEM;
|
|
}
|
|
ret = pdc_pat_mem_read_cell_pdt(&pat_pret, pdt_entry,
|
|
MAX_PDT_ENTRIES);
|
|
bad_mem_ptr = &pdt_entry[old_num_entries];
|
|
break;
|
|
case PDT_PAT_NEW:
|
|
ret = pdc_pat_mem_read_pd_pdt(&pat_pret,
|
|
pdt_entry,
|
|
num * sizeof(unsigned long),
|
|
old_num_entries * sizeof(unsigned long));
|
|
bad_mem_ptr = &pdt_entry[0];
|
|
break;
|
|
#endif
|
|
default:
|
|
ret = pdc_mem_pdt_read_entries(&pdt_read_ret,
|
|
pdt_entry);
|
|
bad_mem_ptr = &pdt_entry[old_num_entries];
|
|
break;
|
|
}
|
|
|
|
/* report and mark memory broken */
|
|
while (num--) {
|
|
unsigned long pde = *bad_mem_ptr++;
|
|
|
|
report_mem_err(pde);
|
|
|
|
#ifdef CONFIG_MEMORY_FAILURE
|
|
if ((pde & PDT_ADDR_PERM_ERR) ||
|
|
((pde & PDT_ADDR_SINGLE_ERR) == 0))
|
|
memory_failure(pde >> PAGE_SHIFT, 0, 0);
|
|
else
|
|
soft_offline_page(
|
|
pfn_to_page(pde >> PAGE_SHIFT), 0);
|
|
#else
|
|
pr_crit("PDT: memory error at 0x%lx ignored.\n"
|
|
"Rebuild kernel with CONFIG_MEMORY_FAILURE=y "
|
|
"for real handling.\n",
|
|
pde & PDT_ADDR_PHYS_MASK);
|
|
#endif
|
|
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int __init pdt_initcall(void)
|
|
{
|
|
struct task_struct *kpdtd_task;
|
|
|
|
if (pdt_type == PDT_NONE)
|
|
return -ENODEV;
|
|
|
|
kpdtd_task = kthread_create(pdt_mainloop, NULL, "kpdtd");
|
|
if (IS_ERR(kpdtd_task))
|
|
return PTR_ERR(kpdtd_task);
|
|
|
|
wake_up_process(kpdtd_task);
|
|
|
|
return 0;
|
|
}
|
|
|
|
late_initcall(pdt_initcall);
|