diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /arch/parisc/kernel/pdt.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | arch/parisc/kernel/pdt.c | 362 |
1 files changed, 362 insertions, 0 deletions
diff --git a/arch/parisc/kernel/pdt.c b/arch/parisc/kernel/pdt.c new file mode 100644 index 000000000..e391b175f --- /dev/null +++ b/arch/parisc/kernel/pdt.c @@ -0,0 +1,362 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * 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 <linux/pgtable.h> +#include <linux/swap.h> +#include <linux/swapops.h> + +#include <asm/pdc.h> +#include <asm/pdcpat.h> +#include <asm/sections.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); + num_poisoned_pages_inc(); + } +} + + +/* + * 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); + else + soft_offline_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_run(pdt_mainloop, NULL, "kpdtd"); + if (IS_ERR(kpdtd_task)) + return PTR_ERR(kpdtd_task); + + return 0; +} + +late_initcall(pdt_initcall); |