linux-loongson/arch/x86/kernel/cpu/mce/amd.c
Yazen Ghannam 5f6e3b7206 x86/mce/amd: Fix threshold limit reset
The MCA threshold limit must be reset after servicing the interrupt.

Currently, the restart function doesn't have an explicit check for this.  It
makes some assumptions based on the current limit and what's in the registers.
These assumptions don't always hold, so the limit won't be reset in some
cases.

Make the reset condition explicit. Either an interrupt/overflow has occurred
or the bank is being initialized.

Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/20250624-wip-mca-updates-v4-4-236dd74f645f@amd.com
2025-06-27 13:16:23 +02:00

1360 lines
33 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* (c) 2005-2016 Advanced Micro Devices, Inc.
*
* Written by Jacob Shin - AMD, Inc.
* Maintained by: Borislav Petkov <bp@alien8.de>
*/
#include <linux/interrupt.h>
#include <linux/notifier.h>
#include <linux/kobject.h>
#include <linux/percpu.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/sysfs.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/cpu.h>
#include <linux/smp.h>
#include <linux/string.h>
#include <asm/traps.h>
#include <asm/apic.h>
#include <asm/mce.h>
#include <asm/msr.h>
#include <asm/trace/irq_vectors.h>
#include "internal.h"
#define NR_BLOCKS 5
#define THRESHOLD_MAX 0xFFF
#define INT_TYPE_APIC 0x00020000
#define MASK_VALID_HI 0x80000000
#define MASK_CNTP_HI 0x40000000
#define MASK_LOCKED_HI 0x20000000
#define MASK_LVTOFF_HI 0x00F00000
#define MASK_COUNT_EN_HI 0x00080000
#define MASK_INT_TYPE_HI 0x00060000
#define MASK_OVERFLOW_HI 0x00010000
#define MASK_ERR_COUNT_HI 0x00000FFF
#define MASK_BLKPTR_LO 0xFF000000
#define MCG_XBLK_ADDR 0xC0000400
/* Deferred error settings */
#define MSR_CU_DEF_ERR 0xC0000410
#define MASK_DEF_LVTOFF 0x000000F0
#define MASK_DEF_INT_TYPE 0x00000006
#define DEF_LVT_OFF 0x2
#define DEF_INT_TYPE_APIC 0x2
/* Scalable MCA: */
/* Threshold LVT offset is at MSR0xC0000410[15:12] */
#define SMCA_THR_LVT_OFF 0xF000
static bool thresholding_irq_en;
static const char * const th_names[] = {
"load_store",
"insn_fetch",
"combined_unit",
"decode_unit",
"northbridge",
"execution_unit",
};
static const char * const smca_umc_block_names[] = {
"dram_ecc",
"misc_umc"
};
#define HWID_MCATYPE(hwid, mcatype) (((hwid) << 16) | (mcatype))
struct smca_hwid {
unsigned int bank_type; /* Use with smca_bank_types for easy indexing. */
u32 hwid_mcatype; /* (hwid,mcatype) tuple */
};
struct smca_bank {
const struct smca_hwid *hwid;
u32 id; /* Value of MCA_IPID[InstanceId]. */
u8 sysfs_id; /* Value used for sysfs name. */
};
static DEFINE_PER_CPU_READ_MOSTLY(struct smca_bank[MAX_NR_BANKS], smca_banks);
static DEFINE_PER_CPU_READ_MOSTLY(u8[N_SMCA_BANK_TYPES], smca_bank_counts);
static const char * const smca_names[] = {
[SMCA_LS ... SMCA_LS_V2] = "load_store",
[SMCA_IF] = "insn_fetch",
[SMCA_L2_CACHE] = "l2_cache",
[SMCA_DE] = "decode_unit",
[SMCA_RESERVED] = "reserved",
[SMCA_EX] = "execution_unit",
[SMCA_FP] = "floating_point",
[SMCA_L3_CACHE] = "l3_cache",
[SMCA_CS ... SMCA_CS_V2] = "coherent_slave",
[SMCA_PIE] = "pie",
/* UMC v2 is separate because both of them can exist in a single system. */
[SMCA_UMC] = "umc",
[SMCA_UMC_V2] = "umc_v2",
[SMCA_MA_LLC] = "ma_llc",
[SMCA_PB] = "param_block",
[SMCA_PSP ... SMCA_PSP_V2] = "psp",
[SMCA_SMU ... SMCA_SMU_V2] = "smu",
[SMCA_MP5] = "mp5",
[SMCA_MPDMA] = "mpdma",
[SMCA_NBIO] = "nbio",
[SMCA_PCIE ... SMCA_PCIE_V2] = "pcie",
[SMCA_XGMI_PCS] = "xgmi_pcs",
[SMCA_NBIF] = "nbif",
[SMCA_SHUB] = "shub",
[SMCA_SATA] = "sata",
[SMCA_USB] = "usb",
[SMCA_USR_DP] = "usr_dp",
[SMCA_USR_CP] = "usr_cp",
[SMCA_GMI_PCS] = "gmi_pcs",
[SMCA_XGMI_PHY] = "xgmi_phy",
[SMCA_WAFL_PHY] = "wafl_phy",
[SMCA_GMI_PHY] = "gmi_phy",
};
static const char *smca_get_name(enum smca_bank_types t)
{
if (t >= N_SMCA_BANK_TYPES)
return NULL;
return smca_names[t];
}
enum smca_bank_types smca_get_bank_type(unsigned int cpu, unsigned int bank)
{
struct smca_bank *b;
if (bank >= MAX_NR_BANKS)
return N_SMCA_BANK_TYPES;
b = &per_cpu(smca_banks, cpu)[bank];
if (!b->hwid)
return N_SMCA_BANK_TYPES;
return b->hwid->bank_type;
}
EXPORT_SYMBOL_GPL(smca_get_bank_type);
static const struct smca_hwid smca_hwid_mcatypes[] = {
/* { bank_type, hwid_mcatype } */
/* Reserved type */
{ SMCA_RESERVED, HWID_MCATYPE(0x00, 0x0) },
/* ZN Core (HWID=0xB0) MCA types */
{ SMCA_LS, HWID_MCATYPE(0xB0, 0x0) },
{ SMCA_LS_V2, HWID_MCATYPE(0xB0, 0x10) },
{ SMCA_IF, HWID_MCATYPE(0xB0, 0x1) },
{ SMCA_L2_CACHE, HWID_MCATYPE(0xB0, 0x2) },
{ SMCA_DE, HWID_MCATYPE(0xB0, 0x3) },
/* HWID 0xB0 MCATYPE 0x4 is Reserved */
{ SMCA_EX, HWID_MCATYPE(0xB0, 0x5) },
{ SMCA_FP, HWID_MCATYPE(0xB0, 0x6) },
{ SMCA_L3_CACHE, HWID_MCATYPE(0xB0, 0x7) },
/* Data Fabric MCA types */
{ SMCA_CS, HWID_MCATYPE(0x2E, 0x0) },
{ SMCA_PIE, HWID_MCATYPE(0x2E, 0x1) },
{ SMCA_CS_V2, HWID_MCATYPE(0x2E, 0x2) },
{ SMCA_MA_LLC, HWID_MCATYPE(0x2E, 0x4) },
/* Unified Memory Controller MCA type */
{ SMCA_UMC, HWID_MCATYPE(0x96, 0x0) },
{ SMCA_UMC_V2, HWID_MCATYPE(0x96, 0x1) },
/* Parameter Block MCA type */
{ SMCA_PB, HWID_MCATYPE(0x05, 0x0) },
/* Platform Security Processor MCA type */
{ SMCA_PSP, HWID_MCATYPE(0xFF, 0x0) },
{ SMCA_PSP_V2, HWID_MCATYPE(0xFF, 0x1) },
/* System Management Unit MCA type */
{ SMCA_SMU, HWID_MCATYPE(0x01, 0x0) },
{ SMCA_SMU_V2, HWID_MCATYPE(0x01, 0x1) },
/* Microprocessor 5 Unit MCA type */
{ SMCA_MP5, HWID_MCATYPE(0x01, 0x2) },
/* MPDMA MCA type */
{ SMCA_MPDMA, HWID_MCATYPE(0x01, 0x3) },
/* Northbridge IO Unit MCA type */
{ SMCA_NBIO, HWID_MCATYPE(0x18, 0x0) },
/* PCI Express Unit MCA type */
{ SMCA_PCIE, HWID_MCATYPE(0x46, 0x0) },
{ SMCA_PCIE_V2, HWID_MCATYPE(0x46, 0x1) },
{ SMCA_XGMI_PCS, HWID_MCATYPE(0x50, 0x0) },
{ SMCA_NBIF, HWID_MCATYPE(0x6C, 0x0) },
{ SMCA_SHUB, HWID_MCATYPE(0x80, 0x0) },
{ SMCA_SATA, HWID_MCATYPE(0xA8, 0x0) },
{ SMCA_USB, HWID_MCATYPE(0xAA, 0x0) },
{ SMCA_USR_DP, HWID_MCATYPE(0x170, 0x0) },
{ SMCA_USR_CP, HWID_MCATYPE(0x180, 0x0) },
{ SMCA_GMI_PCS, HWID_MCATYPE(0x241, 0x0) },
{ SMCA_XGMI_PHY, HWID_MCATYPE(0x259, 0x0) },
{ SMCA_WAFL_PHY, HWID_MCATYPE(0x267, 0x0) },
{ SMCA_GMI_PHY, HWID_MCATYPE(0x269, 0x0) },
};
/*
* In SMCA enabled processors, we can have multiple banks for a given IP type.
* So to define a unique name for each bank, we use a temp c-string to append
* the MCA_IPID[InstanceId] to type's name in get_name().
*
* InstanceId is 32 bits which is 8 characters. Make sure MAX_MCATYPE_NAME_LEN
* is greater than 8 plus 1 (for underscore) plus length of longest type name.
*/
#define MAX_MCATYPE_NAME_LEN 30
static char buf_mcatype[MAX_MCATYPE_NAME_LEN];
struct threshold_block {
/* This block's number within its bank. */
unsigned int block;
/* MCA bank number that contains this block. */
unsigned int bank;
/* CPU which controls this block's MCA bank. */
unsigned int cpu;
/* MCA_MISC MSR address for this block. */
u32 address;
/* Enable/Disable APIC interrupt. */
bool interrupt_enable;
/* Bank can generate an interrupt. */
bool interrupt_capable;
/* Value upon which threshold interrupt is generated. */
u16 threshold_limit;
/* sysfs object */
struct kobject kobj;
/* List of threshold blocks within this block's MCA bank. */
struct list_head miscj;
};
struct threshold_bank {
struct kobject *kobj;
struct threshold_block *blocks;
};
static DEFINE_PER_CPU(struct threshold_bank **, threshold_banks);
/*
* A list of the banks enabled on each logical CPU. Controls which respective
* descriptors to initialize later in mce_threshold_create_device().
*/
static DEFINE_PER_CPU(u64, bank_map);
/* Map of banks that have more than MCA_MISC0 available. */
static DEFINE_PER_CPU(u64, smca_misc_banks_map);
static void amd_threshold_interrupt(void);
static void amd_deferred_error_interrupt(void);
static void default_deferred_error_interrupt(void)
{
pr_err("Unexpected deferred interrupt at vector %x\n", DEFERRED_ERROR_VECTOR);
}
void (*deferred_error_int_vector)(void) = default_deferred_error_interrupt;
static void smca_set_misc_banks_map(unsigned int bank, unsigned int cpu)
{
u32 low, high;
/*
* For SMCA enabled processors, BLKPTR field of the first MISC register
* (MCx_MISC0) indicates presence of additional MISC regs set (MISC1-4).
*/
if (rdmsr_safe(MSR_AMD64_SMCA_MCx_CONFIG(bank), &low, &high))
return;
if (!(low & MCI_CONFIG_MCAX))
return;
if (rdmsr_safe(MSR_AMD64_SMCA_MCx_MISC(bank), &low, &high))
return;
if (low & MASK_BLKPTR_LO)
per_cpu(smca_misc_banks_map, cpu) |= BIT_ULL(bank);
}
static void smca_configure(unsigned int bank, unsigned int cpu)
{
u8 *bank_counts = this_cpu_ptr(smca_bank_counts);
const struct smca_hwid *s_hwid;
unsigned int i, hwid_mcatype;
u32 high, low;
u32 smca_config = MSR_AMD64_SMCA_MCx_CONFIG(bank);
/* Set appropriate bits in MCA_CONFIG */
if (!rdmsr_safe(smca_config, &low, &high)) {
/*
* OS is required to set the MCAX bit to acknowledge that it is
* now using the new MSR ranges and new registers under each
* bank. It also means that the OS will configure deferred
* errors in the new MCx_CONFIG register. If the bit is not set,
* uncorrectable errors will cause a system panic.
*
* MCA_CONFIG[MCAX] is bit 32 (0 in the high portion of the MSR.)
*/
high |= BIT(0);
/*
* SMCA sets the Deferred Error Interrupt type per bank.
*
* MCA_CONFIG[DeferredIntTypeSupported] is bit 5, and tells us
* if the DeferredIntType bit field is available.
*
* MCA_CONFIG[DeferredIntType] is bits [38:37] ([6:5] in the
* high portion of the MSR). OS should set this to 0x1 to enable
* APIC based interrupt. First, check that no interrupt has been
* set.
*/
if ((low & BIT(5)) && !((high >> 5) & 0x3))
high |= BIT(5);
this_cpu_ptr(mce_banks_array)[bank].lsb_in_status = !!(low & BIT(8));
wrmsr(smca_config, low, high);
}
smca_set_misc_banks_map(bank, cpu);
if (rdmsr_safe(MSR_AMD64_SMCA_MCx_IPID(bank), &low, &high)) {
pr_warn("Failed to read MCA_IPID for bank %d\n", bank);
return;
}
hwid_mcatype = HWID_MCATYPE(high & MCI_IPID_HWID,
(high & MCI_IPID_MCATYPE) >> 16);
for (i = 0; i < ARRAY_SIZE(smca_hwid_mcatypes); i++) {
s_hwid = &smca_hwid_mcatypes[i];
if (hwid_mcatype == s_hwid->hwid_mcatype) {
this_cpu_ptr(smca_banks)[bank].hwid = s_hwid;
this_cpu_ptr(smca_banks)[bank].id = low;
this_cpu_ptr(smca_banks)[bank].sysfs_id = bank_counts[s_hwid->bank_type]++;
break;
}
}
}
struct thresh_restart {
struct threshold_block *b;
int set_lvt_off;
int lvt_off;
u16 old_limit;
};
static const char *bank4_names(const struct threshold_block *b)
{
switch (b->address) {
/* MSR4_MISC0 */
case 0x00000413:
return "dram";
case 0xc0000408:
return "ht_links";
case 0xc0000409:
return "l3_cache";
default:
WARN(1, "Funny MSR: 0x%08x\n", b->address);
return "";
}
};
static bool lvt_interrupt_supported(unsigned int bank, u32 msr_high_bits)
{
/*
* bank 4 supports APIC LVT interrupts implicitly since forever.
*/
if (bank == 4)
return true;
/*
* IntP: interrupt present; if this bit is set, the thresholding
* bank can generate APIC LVT interrupts
*/
return msr_high_bits & BIT(28);
}
static bool lvt_off_valid(struct threshold_block *b, int apic, u32 lo, u32 hi)
{
int msr = (hi & MASK_LVTOFF_HI) >> 20;
if (apic < 0) {
pr_err(FW_BUG "cpu %d, failed to setup threshold interrupt "
"for bank %d, block %d (MSR%08X=0x%x%08x)\n", b->cpu,
b->bank, b->block, b->address, hi, lo);
return false;
}
if (apic != msr) {
/*
* On SMCA CPUs, LVT offset is programmed at a different MSR, and
* the BIOS provides the value. The original field where LVT offset
* was set is reserved. Return early here:
*/
if (mce_flags.smca)
return false;
pr_err(FW_BUG "cpu %d, invalid threshold interrupt offset %d "
"for bank %d, block %d (MSR%08X=0x%x%08x)\n",
b->cpu, apic, b->bank, b->block, b->address, hi, lo);
return false;
}
return true;
};
/* Reprogram MCx_MISC MSR behind this threshold bank. */
static void threshold_restart_bank(void *_tr)
{
struct thresh_restart *tr = _tr;
u32 hi, lo;
/* sysfs write might race against an offline operation */
if (!this_cpu_read(threshold_banks) && !tr->set_lvt_off)
return;
rdmsr(tr->b->address, lo, hi);
/*
* Reset error count and overflow bit.
* This is done during init or after handling an interrupt.
*/
if (hi & MASK_OVERFLOW_HI || tr->set_lvt_off) {
hi &= ~(MASK_ERR_COUNT_HI | MASK_OVERFLOW_HI);
hi |= THRESHOLD_MAX - tr->b->threshold_limit;
} else if (tr->old_limit) { /* change limit w/o reset */
int new_count = (hi & THRESHOLD_MAX) +
(tr->old_limit - tr->b->threshold_limit);
hi = (hi & ~MASK_ERR_COUNT_HI) |
(new_count & THRESHOLD_MAX);
}
/* clear IntType */
hi &= ~MASK_INT_TYPE_HI;
if (!tr->b->interrupt_capable)
goto done;
if (tr->set_lvt_off) {
if (lvt_off_valid(tr->b, tr->lvt_off, lo, hi)) {
/* set new lvt offset */
hi &= ~MASK_LVTOFF_HI;
hi |= tr->lvt_off << 20;
}
}
if (tr->b->interrupt_enable)
hi |= INT_TYPE_APIC;
done:
hi |= MASK_COUNT_EN_HI;
wrmsr(tr->b->address, lo, hi);
}
static void mce_threshold_block_init(struct threshold_block *b, int offset)
{
struct thresh_restart tr = {
.b = b,
.set_lvt_off = 1,
.lvt_off = offset,
};
b->threshold_limit = THRESHOLD_MAX;
threshold_restart_bank(&tr);
};
static int setup_APIC_mce_threshold(int reserved, int new)
{
if (reserved < 0 && !setup_APIC_eilvt(new, THRESHOLD_APIC_VECTOR,
APIC_EILVT_MSG_FIX, 0))
return new;
return reserved;
}
static int setup_APIC_deferred_error(int reserved, int new)
{
if (reserved < 0 && !setup_APIC_eilvt(new, DEFERRED_ERROR_VECTOR,
APIC_EILVT_MSG_FIX, 0))
return new;
return reserved;
}
static void deferred_error_interrupt_enable(struct cpuinfo_x86 *c)
{
u32 low = 0, high = 0;
int def_offset = -1, def_new;
if (rdmsr_safe(MSR_CU_DEF_ERR, &low, &high))
return;
def_new = (low & MASK_DEF_LVTOFF) >> 4;
if (!(low & MASK_DEF_LVTOFF)) {
pr_err(FW_BUG "Your BIOS is not setting up LVT offset 0x2 for deferred error IRQs correctly.\n");
def_new = DEF_LVT_OFF;
low = (low & ~MASK_DEF_LVTOFF) | (DEF_LVT_OFF << 4);
}
def_offset = setup_APIC_deferred_error(def_offset, def_new);
if ((def_offset == def_new) &&
(deferred_error_int_vector != amd_deferred_error_interrupt))
deferred_error_int_vector = amd_deferred_error_interrupt;
if (!mce_flags.smca)
low = (low & ~MASK_DEF_INT_TYPE) | DEF_INT_TYPE_APIC;
wrmsr(MSR_CU_DEF_ERR, low, high);
}
static u32 smca_get_block_address(unsigned int bank, unsigned int block,
unsigned int cpu)
{
if (!block)
return MSR_AMD64_SMCA_MCx_MISC(bank);
if (!(per_cpu(smca_misc_banks_map, cpu) & BIT_ULL(bank)))
return 0;
return MSR_AMD64_SMCA_MCx_MISCy(bank, block - 1);
}
static u32 get_block_address(u32 current_addr, u32 low, u32 high,
unsigned int bank, unsigned int block,
unsigned int cpu)
{
u32 addr = 0, offset = 0;
if ((bank >= per_cpu(mce_num_banks, cpu)) || (block >= NR_BLOCKS))
return addr;
if (mce_flags.smca)
return smca_get_block_address(bank, block, cpu);
/* Fall back to method we used for older processors: */
switch (block) {
case 0:
addr = mca_msr_reg(bank, MCA_MISC);
break;
case 1:
offset = ((low & MASK_BLKPTR_LO) >> 21);
if (offset)
addr = MCG_XBLK_ADDR + offset;
break;
default:
addr = ++current_addr;
}
return addr;
}
static int
prepare_threshold_block(unsigned int bank, unsigned int block, u32 addr,
int offset, u32 misc_high)
{
unsigned int cpu = smp_processor_id();
u32 smca_low, smca_high;
struct threshold_block b;
int new;
if (!block)
per_cpu(bank_map, cpu) |= BIT_ULL(bank);
memset(&b, 0, sizeof(b));
b.cpu = cpu;
b.bank = bank;
b.block = block;
b.address = addr;
b.interrupt_capable = lvt_interrupt_supported(bank, misc_high);
if (!b.interrupt_capable)
goto done;
b.interrupt_enable = 1;
if (!mce_flags.smca) {
new = (misc_high & MASK_LVTOFF_HI) >> 20;
goto set_offset;
}
/* Gather LVT offset for thresholding: */
if (rdmsr_safe(MSR_CU_DEF_ERR, &smca_low, &smca_high))
goto out;
new = (smca_low & SMCA_THR_LVT_OFF) >> 12;
set_offset:
offset = setup_APIC_mce_threshold(offset, new);
if (offset == new)
thresholding_irq_en = true;
done:
mce_threshold_block_init(&b, offset);
out:
return offset;
}
bool amd_filter_mce(struct mce *m)
{
enum smca_bank_types bank_type = smca_get_bank_type(m->extcpu, m->bank);
struct cpuinfo_x86 *c = &boot_cpu_data;
/* See Family 17h Models 10h-2Fh Erratum #1114. */
if (c->x86 == 0x17 &&
c->x86_model >= 0x10 && c->x86_model <= 0x2F &&
bank_type == SMCA_IF && XEC(m->status, 0x3f) == 10)
return true;
/* NB GART TLB error reporting is disabled by default. */
if (c->x86 < 0x17) {
if (m->bank == 4 && XEC(m->status, 0x1f) == 0x5)
return true;
}
return false;
}
/*
* Turn off thresholding banks for the following conditions:
* - MC4_MISC thresholding is not supported on Family 0x15.
* - Prevent possible spurious interrupts from the IF bank on Family 0x17
* Models 0x10-0x2F due to Erratum #1114.
*/
static void disable_err_thresholding(struct cpuinfo_x86 *c, unsigned int bank)
{
int i, num_msrs;
u64 hwcr;
bool need_toggle;
u32 msrs[NR_BLOCKS];
if (c->x86 == 0x15 && bank == 4) {
msrs[0] = 0x00000413; /* MC4_MISC0 */
msrs[1] = 0xc0000408; /* MC4_MISC1 */
num_msrs = 2;
} else if (c->x86 == 0x17 &&
(c->x86_model >= 0x10 && c->x86_model <= 0x2F)) {
if (smca_get_bank_type(smp_processor_id(), bank) != SMCA_IF)
return;
msrs[0] = MSR_AMD64_SMCA_MCx_MISC(bank);
num_msrs = 1;
} else {
return;
}
rdmsrq(MSR_K7_HWCR, hwcr);
/* McStatusWrEn has to be set */
need_toggle = !(hwcr & BIT(18));
if (need_toggle)
wrmsrq(MSR_K7_HWCR, hwcr | BIT(18));
/* Clear CntP bit safely */
for (i = 0; i < num_msrs; i++)
msr_clear_bit(msrs[i], 62);
/* restore old settings */
if (need_toggle)
wrmsrq(MSR_K7_HWCR, hwcr);
}
/* cpu init entry point, called from mce.c with preempt off */
void mce_amd_feature_init(struct cpuinfo_x86 *c)
{
unsigned int bank, block, cpu = smp_processor_id();
u32 low = 0, high = 0, address = 0;
int offset = -1;
for (bank = 0; bank < this_cpu_read(mce_num_banks); ++bank) {
if (mce_flags.smca)
smca_configure(bank, cpu);
disable_err_thresholding(c, bank);
for (block = 0; block < NR_BLOCKS; ++block) {
address = get_block_address(address, low, high, bank, block, cpu);
if (!address)
break;
if (rdmsr_safe(address, &low, &high))
break;
if (!(high & MASK_VALID_HI))
continue;
if (!(high & MASK_CNTP_HI) ||
(high & MASK_LOCKED_HI))
continue;
offset = prepare_threshold_block(bank, block, address, offset, high);
}
}
if (mce_flags.succor)
deferred_error_interrupt_enable(c);
}
/*
* DRAM ECC errors are reported in the Northbridge (bank 4) with
* Extended Error Code 8.
*/
static bool legacy_mce_is_memory_error(struct mce *m)
{
return m->bank == 4 && XEC(m->status, 0x1f) == 8;
}
/*
* DRAM ECC errors are reported in Unified Memory Controllers with
* Extended Error Code 0.
*/
static bool smca_mce_is_memory_error(struct mce *m)
{
enum smca_bank_types bank_type;
if (XEC(m->status, 0x3f))
return false;
bank_type = smca_get_bank_type(m->extcpu, m->bank);
return bank_type == SMCA_UMC || bank_type == SMCA_UMC_V2;
}
bool amd_mce_is_memory_error(struct mce *m)
{
if (mce_flags.smca)
return smca_mce_is_memory_error(m);
else
return legacy_mce_is_memory_error(m);
}
/*
* AMD systems do not have an explicit indicator that the value in MCA_ADDR is
* a system physical address. Therefore, individual cases need to be detected.
* Future cases and checks will be added as needed.
*
* 1) General case
* a) Assume address is not usable.
* 2) Poison errors
* a) Indicated by MCA_STATUS[43]: poison. Defined for all banks except legacy
* northbridge (bank 4).
* b) Refers to poison consumption in the core. Does not include "no action",
* "action optional", or "deferred" error severities.
* c) Will include a usable address so that immediate action can be taken.
* 3) Northbridge DRAM ECC errors
* a) Reported in legacy bank 4 with extended error code (XEC) 8.
* b) MCA_STATUS[43] is *not* defined as poison in legacy bank 4. Therefore,
* this bit should not be checked.
*
* NOTE: SMCA UMC memory errors fall into case #1.
*/
bool amd_mce_usable_address(struct mce *m)
{
/* Check special northbridge case 3) first. */
if (!mce_flags.smca) {
if (legacy_mce_is_memory_error(m))
return true;
else if (m->bank == 4)
return false;
}
/* Check poison bit for all other bank types. */
if (m->status & MCI_STATUS_POISON)
return true;
/* Assume address is not usable for all others. */
return false;
}
static void __log_error(unsigned int bank, u64 status, u64 addr, u64 misc)
{
struct mce_hw_err err;
struct mce *m = &err.m;
mce_prep_record(&err);
m->status = status;
m->misc = misc;
m->bank = bank;
m->tsc = rdtsc();
if (m->status & MCI_STATUS_ADDRV) {
m->addr = addr;
smca_extract_err_addr(m);
}
if (mce_flags.smca) {
rdmsrq(MSR_AMD64_SMCA_MCx_IPID(bank), m->ipid);
if (m->status & MCI_STATUS_SYNDV) {
rdmsrq(MSR_AMD64_SMCA_MCx_SYND(bank), m->synd);
rdmsrq(MSR_AMD64_SMCA_MCx_SYND1(bank), err.vendor.amd.synd1);
rdmsrq(MSR_AMD64_SMCA_MCx_SYND2(bank), err.vendor.amd.synd2);
}
}
mce_log(&err);
}
DEFINE_IDTENTRY_SYSVEC(sysvec_deferred_error)
{
trace_deferred_error_apic_entry(DEFERRED_ERROR_VECTOR);
inc_irq_stat(irq_deferred_error_count);
deferred_error_int_vector();
trace_deferred_error_apic_exit(DEFERRED_ERROR_VECTOR);
apic_eoi();
}
/*
* Returns true if the logged error is deferred. False, otherwise.
*/
static inline bool
_log_error_bank(unsigned int bank, u32 msr_stat, u32 msr_addr, u64 misc)
{
u64 status, addr = 0;
rdmsrq(msr_stat, status);
if (!(status & MCI_STATUS_VAL))
return false;
if (status & MCI_STATUS_ADDRV)
rdmsrq(msr_addr, addr);
__log_error(bank, status, addr, misc);
wrmsrq(msr_stat, 0);
return status & MCI_STATUS_DEFERRED;
}
static bool _log_error_deferred(unsigned int bank, u32 misc)
{
if (!_log_error_bank(bank, mca_msr_reg(bank, MCA_STATUS),
mca_msr_reg(bank, MCA_ADDR), misc))
return false;
/*
* Non-SMCA systems don't have MCA_DESTAT/MCA_DEADDR registers.
* Return true here to avoid accessing these registers.
*/
if (!mce_flags.smca)
return true;
/* Clear MCA_DESTAT if the deferred error was logged from MCA_STATUS. */
wrmsrq(MSR_AMD64_SMCA_MCx_DESTAT(bank), 0);
return true;
}
/*
* We have three scenarios for checking for Deferred errors:
*
* 1) Non-SMCA systems check MCA_STATUS and log error if found.
* 2) SMCA systems check MCA_STATUS. If error is found then log it and also
* clear MCA_DESTAT.
* 3) SMCA systems check MCA_DESTAT, if error was not found in MCA_STATUS, and
* log it.
*/
static void log_error_deferred(unsigned int bank)
{
if (_log_error_deferred(bank, 0))
return;
/*
* Only deferred errors are logged in MCA_DE{STAT,ADDR} so just check
* for a valid error.
*/
_log_error_bank(bank, MSR_AMD64_SMCA_MCx_DESTAT(bank),
MSR_AMD64_SMCA_MCx_DEADDR(bank), 0);
}
/* APIC interrupt handler for deferred errors */
static void amd_deferred_error_interrupt(void)
{
unsigned int bank;
for (bank = 0; bank < this_cpu_read(mce_num_banks); ++bank)
log_error_deferred(bank);
}
static void log_error_thresholding(unsigned int bank, u64 misc)
{
_log_error_deferred(bank, misc);
}
static void log_and_reset_block(struct threshold_block *block)
{
struct thresh_restart tr;
u32 low = 0, high = 0;
if (!block)
return;
if (rdmsr_safe(block->address, &low, &high))
return;
if (!(high & MASK_OVERFLOW_HI))
return;
/* Log the MCE which caused the threshold event. */
log_error_thresholding(block->bank, ((u64)high << 32) | low);
/* Reset threshold block after logging error. */
memset(&tr, 0, sizeof(tr));
tr.b = block;
threshold_restart_bank(&tr);
}
/*
* Threshold interrupt handler will service THRESHOLD_APIC_VECTOR. The interrupt
* goes off when error_count reaches threshold_limit.
*/
static void amd_threshold_interrupt(void)
{
struct threshold_block *first_block = NULL, *block = NULL, *tmp = NULL;
struct threshold_bank **bp = this_cpu_read(threshold_banks);
unsigned int bank, cpu = smp_processor_id();
/*
* Validate that the threshold bank has been initialized already. The
* handler is installed at boot time, but on a hotplug event the
* interrupt might fire before the data has been initialized.
*/
if (!bp)
return;
for (bank = 0; bank < this_cpu_read(mce_num_banks); ++bank) {
if (!(per_cpu(bank_map, cpu) & BIT_ULL(bank)))
continue;
first_block = bp[bank]->blocks;
if (!first_block)
continue;
/*
* The first block is also the head of the list. Check it first
* before iterating over the rest.
*/
log_and_reset_block(first_block);
list_for_each_entry_safe(block, tmp, &first_block->miscj, miscj)
log_and_reset_block(block);
}
}
/*
* Sysfs Interface
*/
struct threshold_attr {
struct attribute attr;
ssize_t (*show) (struct threshold_block *, char *);
ssize_t (*store) (struct threshold_block *, const char *, size_t count);
};
#define SHOW_FIELDS(name) \
static ssize_t show_ ## name(struct threshold_block *b, char *buf) \
{ \
return sprintf(buf, "%lu\n", (unsigned long) b->name); \
}
SHOW_FIELDS(interrupt_enable)
SHOW_FIELDS(threshold_limit)
static ssize_t
store_interrupt_enable(struct threshold_block *b, const char *buf, size_t size)
{
struct thresh_restart tr;
unsigned long new;
if (!b->interrupt_capable)
return -EINVAL;
if (kstrtoul(buf, 0, &new) < 0)
return -EINVAL;
b->interrupt_enable = !!new;
memset(&tr, 0, sizeof(tr));
tr.b = b;
if (smp_call_function_single(b->cpu, threshold_restart_bank, &tr, 1))
return -ENODEV;
return size;
}
static ssize_t
store_threshold_limit(struct threshold_block *b, const char *buf, size_t size)
{
struct thresh_restart tr;
unsigned long new;
if (kstrtoul(buf, 0, &new) < 0)
return -EINVAL;
if (new > THRESHOLD_MAX)
new = THRESHOLD_MAX;
if (new < 1)
new = 1;
memset(&tr, 0, sizeof(tr));
tr.old_limit = b->threshold_limit;
b->threshold_limit = new;
tr.b = b;
if (smp_call_function_single(b->cpu, threshold_restart_bank, &tr, 1))
return -ENODEV;
return size;
}
static ssize_t show_error_count(struct threshold_block *b, char *buf)
{
u32 lo, hi;
/* CPU might be offline by now */
if (rdmsr_on_cpu(b->cpu, b->address, &lo, &hi))
return -ENODEV;
return sprintf(buf, "%u\n", ((hi & THRESHOLD_MAX) -
(THRESHOLD_MAX - b->threshold_limit)));
}
static struct threshold_attr error_count = {
.attr = {.name = __stringify(error_count), .mode = 0444 },
.show = show_error_count,
};
#define RW_ATTR(val) \
static struct threshold_attr val = { \
.attr = {.name = __stringify(val), .mode = 0644 }, \
.show = show_## val, \
.store = store_## val, \
};
RW_ATTR(interrupt_enable);
RW_ATTR(threshold_limit);
static struct attribute *default_attrs[] = {
&threshold_limit.attr,
&error_count.attr,
NULL, /* possibly interrupt_enable if supported, see below */
NULL,
};
ATTRIBUTE_GROUPS(default);
#define to_block(k) container_of(k, struct threshold_block, kobj)
#define to_attr(a) container_of(a, struct threshold_attr, attr)
static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf)
{
struct threshold_block *b = to_block(kobj);
struct threshold_attr *a = to_attr(attr);
ssize_t ret;
ret = a->show ? a->show(b, buf) : -EIO;
return ret;
}
static ssize_t store(struct kobject *kobj, struct attribute *attr,
const char *buf, size_t count)
{
struct threshold_block *b = to_block(kobj);
struct threshold_attr *a = to_attr(attr);
ssize_t ret;
ret = a->store ? a->store(b, buf, count) : -EIO;
return ret;
}
static const struct sysfs_ops threshold_ops = {
.show = show,
.store = store,
};
static void threshold_block_release(struct kobject *kobj);
static const struct kobj_type threshold_ktype = {
.sysfs_ops = &threshold_ops,
.default_groups = default_groups,
.release = threshold_block_release,
};
static const char *get_name(unsigned int cpu, unsigned int bank, struct threshold_block *b)
{
enum smca_bank_types bank_type;
if (!mce_flags.smca) {
if (b && bank == 4)
return bank4_names(b);
return th_names[bank];
}
bank_type = smca_get_bank_type(cpu, bank);
if (b && (bank_type == SMCA_UMC || bank_type == SMCA_UMC_V2)) {
if (b->block < ARRAY_SIZE(smca_umc_block_names))
return smca_umc_block_names[b->block];
}
if (b && b->block) {
snprintf(buf_mcatype, MAX_MCATYPE_NAME_LEN, "th_block_%u", b->block);
return buf_mcatype;
}
if (bank_type >= N_SMCA_BANK_TYPES) {
snprintf(buf_mcatype, MAX_MCATYPE_NAME_LEN, "th_bank_%u", bank);
return buf_mcatype;
}
if (per_cpu(smca_bank_counts, cpu)[bank_type] == 1)
return smca_get_name(bank_type);
snprintf(buf_mcatype, MAX_MCATYPE_NAME_LEN,
"%s_%u", smca_get_name(bank_type),
per_cpu(smca_banks, cpu)[bank].sysfs_id);
return buf_mcatype;
}
static int allocate_threshold_blocks(unsigned int cpu, struct threshold_bank *tb,
unsigned int bank, unsigned int block,
u32 address)
{
struct threshold_block *b = NULL;
u32 low, high;
int err;
if ((bank >= this_cpu_read(mce_num_banks)) || (block >= NR_BLOCKS))
return 0;
if (rdmsr_safe(address, &low, &high))
return 0;
if (!(high & MASK_VALID_HI)) {
if (block)
goto recurse;
else
return 0;
}
if (!(high & MASK_CNTP_HI) ||
(high & MASK_LOCKED_HI))
goto recurse;
b = kzalloc(sizeof(struct threshold_block), GFP_KERNEL);
if (!b)
return -ENOMEM;
b->block = block;
b->bank = bank;
b->cpu = cpu;
b->address = address;
b->interrupt_enable = 0;
b->interrupt_capable = lvt_interrupt_supported(bank, high);
b->threshold_limit = THRESHOLD_MAX;
if (b->interrupt_capable) {
default_attrs[2] = &interrupt_enable.attr;
b->interrupt_enable = 1;
} else {
default_attrs[2] = NULL;
}
INIT_LIST_HEAD(&b->miscj);
/* This is safe as @tb is not visible yet */
if (tb->blocks)
list_add(&b->miscj, &tb->blocks->miscj);
else
tb->blocks = b;
err = kobject_init_and_add(&b->kobj, &threshold_ktype, tb->kobj, get_name(cpu, bank, b));
if (err)
goto out_free;
recurse:
address = get_block_address(address, low, high, bank, ++block, cpu);
if (!address)
return 0;
err = allocate_threshold_blocks(cpu, tb, bank, block, address);
if (err)
goto out_free;
if (b)
kobject_uevent(&b->kobj, KOBJ_ADD);
return 0;
out_free:
if (b) {
list_del(&b->miscj);
kobject_put(&b->kobj);
}
return err;
}
static int threshold_create_bank(struct threshold_bank **bp, unsigned int cpu,
unsigned int bank)
{
struct device *dev = this_cpu_read(mce_device);
struct threshold_bank *b = NULL;
const char *name = get_name(cpu, bank, NULL);
int err = 0;
if (!dev)
return -ENODEV;
b = kzalloc(sizeof(struct threshold_bank), GFP_KERNEL);
if (!b) {
err = -ENOMEM;
goto out;
}
/* Associate the bank with the per-CPU MCE device */
b->kobj = kobject_create_and_add(name, &dev->kobj);
if (!b->kobj) {
err = -EINVAL;
goto out_free;
}
err = allocate_threshold_blocks(cpu, b, bank, 0, mca_msr_reg(bank, MCA_MISC));
if (err)
goto out_kobj;
bp[bank] = b;
return 0;
out_kobj:
kobject_put(b->kobj);
out_free:
kfree(b);
out:
return err;
}
static void threshold_block_release(struct kobject *kobj)
{
kfree(to_block(kobj));
}
static void deallocate_threshold_blocks(struct threshold_bank *bank)
{
struct threshold_block *pos, *tmp;
list_for_each_entry_safe(pos, tmp, &bank->blocks->miscj, miscj) {
list_del(&pos->miscj);
kobject_put(&pos->kobj);
}
kobject_put(&bank->blocks->kobj);
}
static void threshold_remove_bank(struct threshold_bank *bank)
{
if (!bank->blocks)
goto out_free;
deallocate_threshold_blocks(bank);
out_free:
kobject_put(bank->kobj);
kfree(bank);
}
static void __threshold_remove_device(struct threshold_bank **bp)
{
unsigned int bank, numbanks = this_cpu_read(mce_num_banks);
for (bank = 0; bank < numbanks; bank++) {
if (!bp[bank])
continue;
threshold_remove_bank(bp[bank]);
bp[bank] = NULL;
}
kfree(bp);
}
int mce_threshold_remove_device(unsigned int cpu)
{
struct threshold_bank **bp = this_cpu_read(threshold_banks);
if (!bp)
return 0;
/*
* Clear the pointer before cleaning up, so that the interrupt won't
* touch anything of this.
*/
this_cpu_write(threshold_banks, NULL);
__threshold_remove_device(bp);
return 0;
}
/**
* mce_threshold_create_device - Create the per-CPU MCE threshold device
* @cpu: The plugged in CPU
*
* Create directories and files for all valid threshold banks.
*
* This is invoked from the CPU hotplug callback which was installed in
* mcheck_init_device(). The invocation happens in context of the hotplug
* thread running on @cpu. The callback is invoked on all CPUs which are
* online when the callback is installed or during a real hotplug event.
*/
int mce_threshold_create_device(unsigned int cpu)
{
unsigned int numbanks, bank;
struct threshold_bank **bp;
int err;
if (!mce_flags.amd_threshold)
return 0;
bp = this_cpu_read(threshold_banks);
if (bp)
return 0;
numbanks = this_cpu_read(mce_num_banks);
bp = kcalloc(numbanks, sizeof(*bp), GFP_KERNEL);
if (!bp)
return -ENOMEM;
for (bank = 0; bank < numbanks; ++bank) {
if (!(this_cpu_read(bank_map) & BIT_ULL(bank)))
continue;
err = threshold_create_bank(bp, cpu, bank);
if (err) {
__threshold_remove_device(bp);
return err;
}
}
this_cpu_write(threshold_banks, bp);
if (thresholding_irq_en)
mce_threshold_vector = amd_threshold_interrupt;
return 0;
}