diff options
Diffstat (limited to 'arch/x86/kernel/cpu/mce')
| -rw-r--r-- | arch/x86/kernel/cpu/mce/amd.c | 80 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mce/core.c | 87 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mce/inject.c | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mce/intel.c | 304 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mce/internal.h | 66 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mce/threshold.c | 115 |
6 files changed, 400 insertions, 253 deletions
diff --git a/arch/x86/kernel/cpu/mce/amd.c b/arch/x86/kernel/cpu/mce/amd.c index f3517b8a8e91..2b46eb0fdf3a 100644 --- a/arch/x86/kernel/cpu/mce/amd.c +++ b/arch/x86/kernel/cpu/mce/amd.c @@ -87,42 +87,40 @@ struct smca_bank { 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); -struct smca_bank_name { - const char *name; /* Short name for sysfs */ - const char *long_name; /* Long name for pretty-printing */ -}; - -static struct smca_bank_name smca_names[] = { - [SMCA_LS ... SMCA_LS_V2] = { "load_store", "Load Store Unit" }, - [SMCA_IF] = { "insn_fetch", "Instruction Fetch Unit" }, - [SMCA_L2_CACHE] = { "l2_cache", "L2 Cache" }, - [SMCA_DE] = { "decode_unit", "Decode Unit" }, - [SMCA_RESERVED] = { "reserved", "Reserved" }, - [SMCA_EX] = { "execution_unit", "Execution Unit" }, - [SMCA_FP] = { "floating_point", "Floating Point Unit" }, - [SMCA_L3_CACHE] = { "l3_cache", "L3 Cache" }, - [SMCA_CS ... SMCA_CS_V2] = { "coherent_slave", "Coherent Slave" }, - [SMCA_PIE] = { "pie", "Power, Interrupts, etc." }, +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", "Unified Memory Controller" }, - [SMCA_UMC_V2] = { "umc_v2", "Unified Memory Controller v2" }, - [SMCA_PB] = { "param_block", "Parameter Block" }, - [SMCA_PSP ... SMCA_PSP_V2] = { "psp", "Platform Security Processor" }, - [SMCA_SMU ... SMCA_SMU_V2] = { "smu", "System Management Unit" }, - [SMCA_MP5] = { "mp5", "Microprocessor 5 Unit" }, - [SMCA_MPDMA] = { "mpdma", "MPDMA Unit" }, - [SMCA_NBIO] = { "nbio", "Northbridge IO Unit" }, - [SMCA_PCIE ... SMCA_PCIE_V2] = { "pcie", "PCI Express Unit" }, - [SMCA_XGMI_PCS] = { "xgmi_pcs", "Ext Global Memory Interconnect PCS Unit" }, - [SMCA_NBIF] = { "nbif", "NBIF Unit" }, - [SMCA_SHUB] = { "shub", "System Hub Unit" }, - [SMCA_SATA] = { "sata", "SATA Unit" }, - [SMCA_USB] = { "usb", "USB Unit" }, - [SMCA_GMI_PCS] = { "gmi_pcs", "Global Memory Interconnect PCS Unit" }, - [SMCA_XGMI_PHY] = { "xgmi_phy", "Ext Global Memory Interconnect PHY Unit" }, - [SMCA_WAFL_PHY] = { "wafl_phy", "WAFL PHY Unit" }, - [SMCA_GMI_PHY] = { "gmi_phy", "Global Memory Interconnect PHY Unit" }, + [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) @@ -130,17 +128,8 @@ static const char *smca_get_name(enum smca_bank_types t) if (t >= N_SMCA_BANK_TYPES) return NULL; - return smca_names[t].name; -} - -const char *smca_get_long_name(enum smca_bank_types t) -{ - if (t >= N_SMCA_BANK_TYPES) - return NULL; - - return smca_names[t].long_name; + return smca_names[t]; } -EXPORT_SYMBOL_GPL(smca_get_long_name); enum smca_bank_types smca_get_bank_type(unsigned int cpu, unsigned int bank) { @@ -178,6 +167,7 @@ static const struct smca_hwid smca_hwid_mcatypes[] = { { 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) }, @@ -212,6 +202,8 @@ static const struct smca_hwid smca_hwid_mcatypes[] = { { 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) }, diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c index 7b397370b4d6..bc39252bc54f 100644 --- a/arch/x86/kernel/cpu/mce/core.c +++ b/arch/x86/kernel/cpu/mce/core.c @@ -44,6 +44,7 @@ #include <linux/sync_core.h> #include <linux/task_work.h> #include <linux/hardirq.h> +#include <linux/kexec.h> #include <asm/intel-family.h> #include <asm/processor.h> @@ -52,6 +53,7 @@ #include <asm/mce.h> #include <asm/msr.h> #include <asm/reboot.h> +#include <asm/tdx.h> #include "internal.h" @@ -228,11 +230,20 @@ static void wait_for_panic(void) panic("Panicing machine check CPU died"); } +static const char *mce_dump_aux_info(struct mce *m) +{ + if (boot_cpu_has_bug(X86_BUG_TDX_PW_MCE)) + return tdx_dump_mce_info(m); + + return NULL; +} + static noinstr void mce_panic(const char *msg, struct mce *final, char *exp) { struct llist_node *pending; struct mce_evt_llist *l; int apei_err = 0; + const char *memmsg; /* * Allow instrumentation around external facilities usage. Not that it @@ -283,9 +294,29 @@ static noinstr void mce_panic(const char *msg, struct mce *final, char *exp) } if (exp) pr_emerg(HW_ERR "Machine check: %s\n", exp); + + memmsg = mce_dump_aux_info(final); + if (memmsg) + pr_emerg(HW_ERR "Machine check: %s\n", memmsg); + if (!fake_panic) { if (panic_timeout == 0) panic_timeout = mca_cfg.panic_timeout; + + /* + * Kdump skips the poisoned page in order to avoid + * touching the error bits again. Poison the page even + * if the error is fatal and the machine is about to + * panic. + */ + if (kexec_crash_loaded()) { + if (final && (final->status & MCI_STATUS_ADDRV)) { + struct page *p; + p = pfn_to_online_page(final->addr >> PAGE_SHIFT); + if (p) + SetPageHWPoison(p); + } + } panic(msg); } else pr_emerg(HW_ERR "Fake kernel panic: %s\n", msg); @@ -670,6 +701,16 @@ bool machine_check_poll(enum mcp_flags flags, mce_banks_t *b) barrier(); m.status = mce_rdmsrl(mca_msr_reg(i, MCA_STATUS)); + /* + * Update storm tracking here, before checking for the + * MCI_STATUS_VAL bit. Valid corrected errors count + * towards declaring, or maintaining, storm status. No + * error in a bank counts towards avoiding, or ending, + * storm status. + */ + if (!mca_cfg.cmci_disabled) + mce_track_storm(&m); + /* If this entry is not valid, ignore it */ if (!(m.status & MCI_STATUS_VAL)) continue; @@ -1601,13 +1642,6 @@ static unsigned long check_interval = INITIAL_CHECK_INTERVAL; static DEFINE_PER_CPU(unsigned long, mce_next_interval); /* in jiffies */ static DEFINE_PER_CPU(struct timer_list, mce_timer); -static unsigned long mce_adjust_timer_default(unsigned long interval) -{ - return interval; -} - -static unsigned long (*mce_adjust_timer)(unsigned long interval) = mce_adjust_timer_default; - static void __start_timer(struct timer_list *t, unsigned long interval) { unsigned long when = jiffies + interval; @@ -1637,15 +1671,9 @@ static void mce_timer_fn(struct timer_list *t) iv = __this_cpu_read(mce_next_interval); - if (mce_available(this_cpu_ptr(&cpu_info))) { + if (mce_available(this_cpu_ptr(&cpu_info))) mc_poll_banks(); - if (mce_intel_cmci_poll()) { - iv = mce_adjust_timer(iv); - goto done; - } - } - /* * Alert userspace if needed. If we logged an MCE, reduce the polling * interval, otherwise increase the polling interval. @@ -1655,23 +1683,29 @@ static void mce_timer_fn(struct timer_list *t) else iv = min(iv * 2, round_jiffies_relative(check_interval * HZ)); -done: - __this_cpu_write(mce_next_interval, iv); - __start_timer(t, iv); + if (mce_get_storm_mode()) { + __start_timer(t, HZ); + } else { + __this_cpu_write(mce_next_interval, iv); + __start_timer(t, iv); + } } /* - * Ensure that the timer is firing in @interval from now. + * When a storm starts on any bank on this CPU, switch to polling + * once per second. When the storm ends, revert to the default + * polling interval. */ -void mce_timer_kick(unsigned long interval) +void mce_timer_kick(bool storm) { struct timer_list *t = this_cpu_ptr(&mce_timer); - unsigned long iv = __this_cpu_read(mce_next_interval); - __start_timer(t, interval); + mce_set_storm_mode(storm); - if (interval < iv) - __this_cpu_write(mce_next_interval, interval); + if (storm) + __start_timer(t, HZ); + else + __this_cpu_write(mce_next_interval, check_interval * HZ); } /* Must not be called in IRQ context where del_timer_sync() can deadlock */ @@ -1995,7 +2029,6 @@ static void mce_zhaoxin_feature_init(struct cpuinfo_x86 *c) intel_init_cmci(); intel_init_lmce(); - mce_adjust_timer = cmci_intel_adjust_timer; } static void mce_zhaoxin_feature_clear(struct cpuinfo_x86 *c) @@ -2008,7 +2041,6 @@ static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 *c) switch (c->x86_vendor) { case X86_VENDOR_INTEL: mce_intel_feature_init(c); - mce_adjust_timer = cmci_intel_adjust_timer; break; case X86_VENDOR_AMD: { @@ -2568,9 +2600,6 @@ static int mce_device_create(unsigned int cpu) int err; int i, j; - if (!mce_available(&boot_cpu_data)) - return -EIO; - dev = per_cpu(mce_device, cpu); if (dev) return 0; @@ -2665,8 +2694,6 @@ static void mce_reenable_cpu(void) static int mce_cpu_dead(unsigned int cpu) { - mce_intel_hcpu_update(cpu); - /* intentionally ignoring frozen here */ if (!cpuhp_tasks_frozen) cmci_rediscover(); diff --git a/arch/x86/kernel/cpu/mce/inject.c b/arch/x86/kernel/cpu/mce/inject.c index 4d8d4bcf915d..72f0695c3dc1 100644 --- a/arch/x86/kernel/cpu/mce/inject.c +++ b/arch/x86/kernel/cpu/mce/inject.c @@ -746,6 +746,7 @@ static void check_hw_inj_possible(void) wrmsrl_safe(mca_msr_reg(bank, MCA_STATUS), status); rdmsrl_safe(mca_msr_reg(bank, MCA_STATUS), &status); + wrmsrl_safe(mca_msr_reg(bank, MCA_STATUS), 0); if (!status) { hw_injection_possible = false; diff --git a/arch/x86/kernel/cpu/mce/intel.c b/arch/x86/kernel/cpu/mce/intel.c index 52bce533ddcc..399b62e223d2 100644 --- a/arch/x86/kernel/cpu/mce/intel.c +++ b/arch/x86/kernel/cpu/mce/intel.c @@ -42,15 +42,6 @@ static DEFINE_PER_CPU(mce_banks_t, mce_banks_owned); /* - * CMCI storm detection backoff counter - * - * During storm, we reset this counter to INITIAL_CHECK_INTERVAL in case we've - * encountered an error. If not, we decrement it by one. We signal the end of - * the CMCI storm when it reaches 0. - */ -static DEFINE_PER_CPU(int, cmci_backoff_cnt); - -/* * cmci_discover_lock protects against parallel discovery attempts * which could race against each other. */ @@ -63,22 +54,26 @@ static DEFINE_RAW_SPINLOCK(cmci_discover_lock); */ static DEFINE_SPINLOCK(cmci_poll_lock); +/* Linux non-storm CMCI threshold (may be overridden by BIOS) */ #define CMCI_THRESHOLD 1 -#define CMCI_POLL_INTERVAL (30 * HZ) -#define CMCI_STORM_INTERVAL (HZ) -#define CMCI_STORM_THRESHOLD 15 -static DEFINE_PER_CPU(unsigned long, cmci_time_stamp); -static DEFINE_PER_CPU(unsigned int, cmci_storm_cnt); -static DEFINE_PER_CPU(unsigned int, cmci_storm_state); - -enum { - CMCI_STORM_NONE, - CMCI_STORM_ACTIVE, - CMCI_STORM_SUBSIDED, -}; +/* + * MCi_CTL2 threshold for each bank when there is no storm. + * Default value for each bank may have been set by BIOS. + */ +static u16 cmci_threshold[MAX_NR_BANKS]; -static atomic_t cmci_storm_on_cpus; +/* + * High threshold to limit CMCI rate during storms. Max supported is + * 0x7FFF. Use this slightly smaller value so it has a distinctive + * signature when some asks "Why am I not seeing all corrected errors?" + * A high threshold is used instead of just disabling CMCI for a + * bank because both corrected and uncorrected errors may be logged + * in the same bank and signalled with CMCI. The threshold only applies + * to corrected errors, so keeping CMCI enabled means that uncorrected + * errors will still be processed in a timely fashion. + */ +#define CMCI_STORM_THRESHOLD 32749 static int cmci_supported(int *banks) { @@ -134,204 +129,166 @@ static bool lmce_supported(void) return tmp & FEAT_CTL_LMCE_ENABLED; } -bool mce_intel_cmci_poll(void) +/* + * Set a new CMCI threshold value. Preserve the state of the + * MCI_CTL2_CMCI_EN bit in case this happens during a + * cmci_rediscover() operation. + */ +static void cmci_set_threshold(int bank, int thresh) { - if (__this_cpu_read(cmci_storm_state) == CMCI_STORM_NONE) - return false; - - /* - * Reset the counter if we've logged an error in the last poll - * during the storm. - */ - if (machine_check_poll(0, this_cpu_ptr(&mce_banks_owned))) - this_cpu_write(cmci_backoff_cnt, INITIAL_CHECK_INTERVAL); - else - this_cpu_dec(cmci_backoff_cnt); + unsigned long flags; + u64 val; - return true; + raw_spin_lock_irqsave(&cmci_discover_lock, flags); + rdmsrl(MSR_IA32_MCx_CTL2(bank), val); + val &= ~MCI_CTL2_CMCI_THRESHOLD_MASK; + wrmsrl(MSR_IA32_MCx_CTL2(bank), val | thresh); + raw_spin_unlock_irqrestore(&cmci_discover_lock, flags); } -void mce_intel_hcpu_update(unsigned long cpu) +void mce_intel_handle_storm(int bank, bool on) { - if (per_cpu(cmci_storm_state, cpu) == CMCI_STORM_ACTIVE) - atomic_dec(&cmci_storm_on_cpus); + if (on) + cmci_set_threshold(bank, CMCI_STORM_THRESHOLD); + else + cmci_set_threshold(bank, cmci_threshold[bank]); +} - per_cpu(cmci_storm_state, cpu) = CMCI_STORM_NONE; +/* + * The interrupt handler. This is called on every event. + * Just call the poller directly to log any events. + * This could in theory increase the threshold under high load, + * but doesn't for now. + */ +static void intel_threshold_interrupt(void) +{ + machine_check_poll(MCP_TIMESTAMP, this_cpu_ptr(&mce_banks_owned)); } -static void cmci_toggle_interrupt_mode(bool on) +/* + * Check all the reasons why current CPU cannot claim + * ownership of a bank. + * 1: CPU already owns this bank + * 2: BIOS owns this bank + * 3: Some other CPU owns this bank + */ +static bool cmci_skip_bank(int bank, u64 *val) { - unsigned long flags, *owned; - int bank; - u64 val; + unsigned long *owned = (void *)this_cpu_ptr(&mce_banks_owned); - raw_spin_lock_irqsave(&cmci_discover_lock, flags); - owned = this_cpu_ptr(mce_banks_owned); - for_each_set_bit(bank, owned, MAX_NR_BANKS) { - rdmsrl(MSR_IA32_MCx_CTL2(bank), val); + if (test_bit(bank, owned)) + return true; - if (on) - val |= MCI_CTL2_CMCI_EN; - else - val &= ~MCI_CTL2_CMCI_EN; + /* Skip banks in firmware first mode */ + if (test_bit(bank, mce_banks_ce_disabled)) + return true; - wrmsrl(MSR_IA32_MCx_CTL2(bank), val); - } - raw_spin_unlock_irqrestore(&cmci_discover_lock, flags); -} + rdmsrl(MSR_IA32_MCx_CTL2(bank), *val); -unsigned long cmci_intel_adjust_timer(unsigned long interval) -{ - if ((this_cpu_read(cmci_backoff_cnt) > 0) && - (__this_cpu_read(cmci_storm_state) == CMCI_STORM_ACTIVE)) { - mce_notify_irq(); - return CMCI_STORM_INTERVAL; + /* Already owned by someone else? */ + if (*val & MCI_CTL2_CMCI_EN) { + clear_bit(bank, owned); + __clear_bit(bank, this_cpu_ptr(mce_poll_banks)); + return true; } - switch (__this_cpu_read(cmci_storm_state)) { - case CMCI_STORM_ACTIVE: - - /* - * We switch back to interrupt mode once the poll timer has - * silenced itself. That means no events recorded and the timer - * interval is back to our poll interval. - */ - __this_cpu_write(cmci_storm_state, CMCI_STORM_SUBSIDED); - if (!atomic_sub_return(1, &cmci_storm_on_cpus)) - pr_notice("CMCI storm subsided: switching to interrupt mode\n"); + return false; +} - fallthrough; +/* + * Decide which CMCI interrupt threshold to use: + * 1: If this bank is in storm mode from whichever CPU was + * the previous owner, stay in storm mode. + * 2: If ignoring any threshold set by BIOS, set Linux default + * 3: Try to honor BIOS threshold (unless buggy BIOS set it at zero). + */ +static u64 cmci_pick_threshold(u64 val, int *bios_zero_thresh) +{ + if ((val & MCI_CTL2_CMCI_THRESHOLD_MASK) == CMCI_STORM_THRESHOLD) + return val; - case CMCI_STORM_SUBSIDED: + if (!mca_cfg.bios_cmci_threshold) { + val &= ~MCI_CTL2_CMCI_THRESHOLD_MASK; + val |= CMCI_THRESHOLD; + } else if (!(val & MCI_CTL2_CMCI_THRESHOLD_MASK)) { /* - * We wait for all CPUs to go back to SUBSIDED state. When that - * happens we switch back to interrupt mode. + * If bios_cmci_threshold boot option was specified + * but the threshold is zero, we'll try to initialize + * it to 1. */ - if (!atomic_read(&cmci_storm_on_cpus)) { - __this_cpu_write(cmci_storm_state, CMCI_STORM_NONE); - cmci_toggle_interrupt_mode(true); - cmci_recheck(); - } - return CMCI_POLL_INTERVAL; - default: - - /* We have shiny weather. Let the poll do whatever it thinks. */ - return interval; + *bios_zero_thresh = 1; + val |= CMCI_THRESHOLD; } + + return val; } -static bool cmci_storm_detect(void) +/* + * Try to claim ownership of a bank. + */ +static void cmci_claim_bank(int bank, u64 val, int bios_zero_thresh, int *bios_wrong_thresh) { - unsigned int cnt = __this_cpu_read(cmci_storm_cnt); - unsigned long ts = __this_cpu_read(cmci_time_stamp); - unsigned long now = jiffies; - int r; + struct mca_storm_desc *storm = this_cpu_ptr(&storm_desc); - if (__this_cpu_read(cmci_storm_state) != CMCI_STORM_NONE) - return true; + val |= MCI_CTL2_CMCI_EN; + wrmsrl(MSR_IA32_MCx_CTL2(bank), val); + rdmsrl(MSR_IA32_MCx_CTL2(bank), val); - if (time_before_eq(now, ts + CMCI_STORM_INTERVAL)) { - cnt++; - } else { - cnt = 1; - __this_cpu_write(cmci_time_stamp, now); + /* If the enable bit did not stick, this bank should be polled. */ + if (!(val & MCI_CTL2_CMCI_EN)) { + WARN_ON(!test_bit(bank, this_cpu_ptr(mce_poll_banks))); + storm->banks[bank].poll_only = true; + return; } - __this_cpu_write(cmci_storm_cnt, cnt); - if (cnt <= CMCI_STORM_THRESHOLD) - return false; - - cmci_toggle_interrupt_mode(false); - __this_cpu_write(cmci_storm_state, CMCI_STORM_ACTIVE); - r = atomic_add_return(1, &cmci_storm_on_cpus); - mce_timer_kick(CMCI_STORM_INTERVAL); - this_cpu_write(cmci_backoff_cnt, INITIAL_CHECK_INTERVAL); + /* This CPU successfully set the enable bit. */ + set_bit(bank, (void *)this_cpu_ptr(&mce_banks_owned)); - if (r == 1) - pr_notice("CMCI storm detected: switching to poll mode\n"); - return true; -} + if ((val & MCI_CTL2_CMCI_THRESHOLD_MASK) == CMCI_STORM_THRESHOLD) { + pr_notice("CPU%d BANK%d CMCI inherited storm\n", smp_processor_id(), bank); + mce_inherit_storm(bank); + cmci_storm_begin(bank); + } else { + __clear_bit(bank, this_cpu_ptr(mce_poll_banks)); + } -/* - * The interrupt handler. This is called on every event. - * Just call the poller directly to log any events. - * This could in theory increase the threshold under high load, - * but doesn't for now. - */ -static void intel_threshold_interrupt(void) -{ - if (cmci_storm_detect()) - return; + /* + * We are able to set thresholds for some banks that + * had a threshold of 0. This means the BIOS has not + * set the thresholds properly or does not work with + * this boot option. Note down now and report later. + */ + if (mca_cfg.bios_cmci_threshold && bios_zero_thresh && + (val & MCI_CTL2_CMCI_THRESHOLD_MASK)) + *bios_wrong_thresh = 1; - machine_check_poll(MCP_TIMESTAMP, this_cpu_ptr(&mce_banks_owned)); + /* Save default threshold for each bank */ + if (cmci_threshold[bank] == 0) + cmci_threshold[bank] = val & MCI_CTL2_CMCI_THRESHOLD_MASK; } /* * Enable CMCI (Corrected Machine Check Interrupt) for available MCE banks * on this CPU. Use the algorithm recommended in the SDM to discover shared - * banks. + * banks. Called during initial bootstrap, and also for hotplug CPU operations + * to rediscover/reassign machine check banks. */ static void cmci_discover(int banks) { - unsigned long *owned = (void *)this_cpu_ptr(&mce_banks_owned); + int bios_wrong_thresh = 0; unsigned long flags; int i; - int bios_wrong_thresh = 0; raw_spin_lock_irqsave(&cmci_discover_lock, flags); for (i = 0; i < banks; i++) { u64 val; int bios_zero_thresh = 0; - if (test_bit(i, owned)) + if (cmci_skip_bank(i, &val)) continue; - /* Skip banks in firmware first mode */ - if (test_bit(i, mce_banks_ce_disabled)) - continue; - - rdmsrl(MSR_IA32_MCx_CTL2(i), val); - - /* Already owned by someone else? */ - if (val & MCI_CTL2_CMCI_EN) { - clear_bit(i, owned); - __clear_bit(i, this_cpu_ptr(mce_poll_banks)); - continue; - } - - if (!mca_cfg.bios_cmci_threshold) { - val &= ~MCI_CTL2_CMCI_THRESHOLD_MASK; - val |= CMCI_THRESHOLD; - } else if (!(val & MCI_CTL2_CMCI_THRESHOLD_MASK)) { - /* - * If bios_cmci_threshold boot option was specified - * but the threshold is zero, we'll try to initialize - * it to 1. - */ - bios_zero_thresh = 1; - val |= CMCI_THRESHOLD; - } - - val |= MCI_CTL2_CMCI_EN; - wrmsrl(MSR_IA32_MCx_CTL2(i), val); - rdmsrl(MSR_IA32_MCx_CTL2(i), val); - - /* Did the enable bit stick? -- the bank supports CMCI */ - if (val & MCI_CTL2_CMCI_EN) { - set_bit(i, owned); - __clear_bit(i, this_cpu_ptr(mce_poll_banks)); - /* - * We are able to set thresholds for some banks that - * had a threshold of 0. This means the BIOS has not - * set the thresholds properly or does not work with - * this boot option. Note down now and report later. - */ - if (mca_cfg.bios_cmci_threshold && bios_zero_thresh && - (val & MCI_CTL2_CMCI_THRESHOLD_MASK)) - bios_wrong_thresh = 1; - } else { - WARN_ON(!test_bit(i, this_cpu_ptr(mce_poll_banks))); - } + val = cmci_pick_threshold(val, &bios_zero_thresh); + cmci_claim_bank(i, val, bios_zero_thresh, &bios_wrong_thresh); } raw_spin_unlock_irqrestore(&cmci_discover_lock, flags); if (mca_cfg.bios_cmci_threshold && bios_wrong_thresh) { @@ -370,6 +327,9 @@ static void __cmci_disable_bank(int bank) val &= ~MCI_CTL2_CMCI_EN; wrmsrl(MSR_IA32_MCx_CTL2(bank), val); __clear_bit(bank, this_cpu_ptr(mce_banks_owned)); + + if ((val & MCI_CTL2_CMCI_THRESHOLD_MASK) == CMCI_STORM_THRESHOLD) + cmci_storm_end(bank); } /* diff --git a/arch/x86/kernel/cpu/mce/internal.h b/arch/x86/kernel/cpu/mce/internal.h index e13a26c9c0ac..01f8f03969e6 100644 --- a/arch/x86/kernel/cpu/mce/internal.h +++ b/arch/x86/kernel/cpu/mce/internal.h @@ -41,9 +41,7 @@ struct dentry *mce_get_debugfs_dir(void); extern mce_banks_t mce_banks_ce_disabled; #ifdef CONFIG_X86_MCE_INTEL -unsigned long cmci_intel_adjust_timer(unsigned long interval); -bool mce_intel_cmci_poll(void); -void mce_intel_hcpu_update(unsigned long cpu); +void mce_intel_handle_storm(int bank, bool on); void cmci_disable_bank(int bank); void intel_init_cmci(void); void intel_init_lmce(void); @@ -51,9 +49,7 @@ void intel_clear_lmce(void); bool intel_filter_mce(struct mce *m); bool intel_mce_usable_address(struct mce *m); #else -# define cmci_intel_adjust_timer mce_adjust_timer_default -static inline bool mce_intel_cmci_poll(void) { return false; } -static inline void mce_intel_hcpu_update(unsigned long cpu) { } +static inline void mce_intel_handle_storm(int bank, bool on) { } static inline void cmci_disable_bank(int bank) { } static inline void intel_init_cmci(void) { } static inline void intel_init_lmce(void) { } @@ -62,7 +58,63 @@ static inline bool intel_filter_mce(struct mce *m) { return false; } static inline bool intel_mce_usable_address(struct mce *m) { return false; } #endif -void mce_timer_kick(unsigned long interval); +void mce_timer_kick(bool storm); + +#ifdef CONFIG_X86_MCE_THRESHOLD +void cmci_storm_begin(unsigned int bank); +void cmci_storm_end(unsigned int bank); +void mce_track_storm(struct mce *mce); +void mce_inherit_storm(unsigned int bank); +bool mce_get_storm_mode(void); +void mce_set_storm_mode(bool storm); +#else +static inline void cmci_storm_begin(unsigned int bank) {} +static inline void cmci_storm_end(unsigned int bank) {} +static inline void mce_track_storm(struct mce *mce) {} +static inline void mce_inherit_storm(unsigned int bank) {} +static inline bool mce_get_storm_mode(void) { return false; } +static inline void mce_set_storm_mode(bool storm) {} +#endif + +/* + * history: Bitmask tracking errors occurrence. Each set bit + * represents an error seen. + * + * timestamp: Last time (in jiffies) that the bank was polled. + * in_storm_mode: Is this bank in storm mode? + * poll_only: Bank does not support CMCI, skip storm tracking. + */ +struct storm_bank { + u64 history; + u64 timestamp; + bool in_storm_mode; + bool poll_only; +}; + +#define NUM_HISTORY_BITS (sizeof(u64) * BITS_PER_BYTE) + +/* How many errors within the history buffer mark the start of a storm. */ +#define STORM_BEGIN_THRESHOLD 5 + +/* + * How many polls of machine check bank without an error before declaring + * the storm is over. Since it is tracked by the bitmasks in the history + * field of struct storm_bank the mask is 30 bits [0 ... 29]. + */ +#define STORM_END_POLL_THRESHOLD 29 + +/* + * banks: per-cpu, per-bank details + * stormy_bank_count: count of MC banks in storm state + * poll_mode: CPU is in poll mode + */ +struct mca_storm_desc { + struct storm_bank banks[MAX_NR_BANKS]; + u8 stormy_bank_count; + bool poll_mode; +}; + +DECLARE_PER_CPU(struct mca_storm_desc, storm_desc); #ifdef CONFIG_ACPI_APEI int apei_write_mce(struct mce *m); diff --git a/arch/x86/kernel/cpu/mce/threshold.c b/arch/x86/kernel/cpu/mce/threshold.c index ef4e7bb5fd88..89e31e1e5c9c 100644 --- a/arch/x86/kernel/cpu/mce/threshold.c +++ b/arch/x86/kernel/cpu/mce/threshold.c @@ -29,3 +29,118 @@ DEFINE_IDTENTRY_SYSVEC(sysvec_threshold) trace_threshold_apic_exit(THRESHOLD_APIC_VECTOR); apic_eoi(); } + +DEFINE_PER_CPU(struct mca_storm_desc, storm_desc); + +void mce_inherit_storm(unsigned int bank) +{ + struct mca_storm_desc *storm = this_cpu_ptr(&storm_desc); + + /* + * Previous CPU owning this bank had put it into storm mode, + * but the precise history of that storm is unknown. Assume + * the worst (all recent polls of the bank found a valid error + * logged). This will avoid the new owner prematurely declaring + * the storm has ended. + */ + storm->banks[bank].history = ~0ull; + storm->banks[bank].timestamp = jiffies; +} + +bool mce_get_storm_mode(void) +{ + return __this_cpu_read(storm_desc.poll_mode); +} + +void mce_set_storm_mode(bool storm) +{ + __this_cpu_write(storm_desc.poll_mode, storm); +} + +static void mce_handle_storm(unsigned int bank, bool on) +{ + switch (boot_cpu_data.x86_vendor) { + case X86_VENDOR_INTEL: + mce_intel_handle_storm(bank, on); + break; + } +} + +void cmci_storm_begin(unsigned int bank) +{ + struct mca_storm_desc *storm = this_cpu_ptr(&storm_desc); + + __set_bit(bank, this_cpu_ptr(mce_poll_banks)); + storm->banks[bank].in_storm_mode = true; + + /* + * If this is the first bank on this CPU to enter storm mode + * start polling. + */ + if (++storm->stormy_bank_count == 1) + mce_timer_kick(true); +} + +void cmci_storm_end(unsigned int bank) +{ + struct mca_storm_desc *storm = this_cpu_ptr(&storm_desc); + + __clear_bit(bank, this_cpu_ptr(mce_poll_banks)); + storm->banks[bank].history = 0; + storm->banks[bank].in_storm_mode = false; + + /* If no banks left in storm mode, stop polling. */ + if (!this_cpu_dec_return(storm_desc.stormy_bank_count)) + mce_timer_kick(false); +} + +void mce_track_storm(struct mce *mce) +{ + struct mca_storm_desc *storm = this_cpu_ptr(&storm_desc); + unsigned long now = jiffies, delta; + unsigned int shift = 1; + u64 history = 0; + + /* No tracking needed for banks that do not support CMCI */ + if (storm->banks[mce->bank].poll_only) + return; + + /* + * When a bank is in storm mode it is polled once per second and + * the history mask will record about the last minute of poll results. + * If it is not in storm mode, then the bank is only checked when + * there is a CMCI interrupt. Check how long it has been since + * this bank was last checked, and adjust the amount of "shift" + * to apply to history. + */ + if (!storm->banks[mce->bank].in_storm_mode) { + delta = now - storm->banks[mce->bank].timestamp; + shift = (delta + HZ) / HZ; + } + + /* If it has been a long time since the last poll, clear history. */ + if (shift < NUM_HISTORY_BITS) + history = storm->banks[mce->bank].history << shift; + + storm->banks[mce->bank].timestamp = now; + + /* History keeps track of corrected errors. VAL=1 && UC=0 */ + if ((mce->status & MCI_STATUS_VAL) && mce_is_correctable(mce)) + history |= 1; + + storm->banks[mce->bank].history = history; + + if (storm->banks[mce->bank].in_storm_mode) { + if (history & GENMASK_ULL(STORM_END_POLL_THRESHOLD, 0)) + return; + printk_deferred(KERN_NOTICE "CPU%d BANK%d CMCI storm subsided\n", smp_processor_id(), mce->bank); + mce_handle_storm(mce->bank, false); + cmci_storm_end(mce->bank); + } else { + if (hweight64(history) < STORM_BEGIN_THRESHOLD) + return; + printk_deferred(KERN_NOTICE "CPU%d BANK%d CMCI storm detected\n", smp_processor_id(), mce->bank); + mce_handle_storm(mce->bank, true); + cmci_storm_begin(mce->bank); + } +} |