diff options
Diffstat (limited to 'arch/x86/kernel/cpu/mcheck/mce-inject.c')
| -rw-r--r-- | arch/x86/kernel/cpu/mcheck/mce-inject.c | 733 |
1 files changed, 0 insertions, 733 deletions
diff --git a/arch/x86/kernel/cpu/mcheck/mce-inject.c b/arch/x86/kernel/cpu/mcheck/mce-inject.c deleted file mode 100644 index 231ad23b24a9..000000000000 --- a/arch/x86/kernel/cpu/mcheck/mce-inject.c +++ /dev/null @@ -1,733 +0,0 @@ -/* - * Machine check injection support. - * Copyright 2008 Intel Corporation. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; version 2 - * of the License. - * - * Authors: - * Andi Kleen - * Ying Huang - * - * The AMD part (from mce_amd_inj.c): a simple MCE injection facility - * for testing different aspects of the RAS code. This driver should be - * built as module so that it can be loaded on production kernels for - * testing purposes. - * - * This file may be distributed under the terms of the GNU General Public - * License version 2. - * - * Copyright (c) 2010-17: Borislav Petkov <bp@alien8.de> - * Advanced Micro Devices Inc. - */ - -#include <linux/cpu.h> -#include <linux/debugfs.h> -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/notifier.h> -#include <linux/pci.h> -#include <linux/uaccess.h> - -#include <asm/amd_nb.h> -#include <asm/apic.h> -#include <asm/irq_vectors.h> -#include <asm/mce.h> -#include <asm/nmi.h> -#include <asm/smp.h> - -#include "mce-internal.h" - -/* - * Collect all the MCi_XXX settings - */ -static struct mce i_mce; -static struct dentry *dfs_inj; - -static u8 n_banks; - -#define MAX_FLAG_OPT_SIZE 3 -#define NBCFG 0x44 - -enum injection_type { - SW_INJ = 0, /* SW injection, simply decode the error */ - HW_INJ, /* Trigger a #MC */ - DFR_INT_INJ, /* Trigger Deferred error interrupt */ - THR_INT_INJ, /* Trigger threshold interrupt */ - N_INJ_TYPES, -}; - -static const char * const flags_options[] = { - [SW_INJ] = "sw", - [HW_INJ] = "hw", - [DFR_INT_INJ] = "df", - [THR_INT_INJ] = "th", - NULL -}; - -/* Set default injection to SW_INJ */ -static enum injection_type inj_type = SW_INJ; - -#define MCE_INJECT_SET(reg) \ -static int inj_##reg##_set(void *data, u64 val) \ -{ \ - struct mce *m = (struct mce *)data; \ - \ - m->reg = val; \ - return 0; \ -} - -MCE_INJECT_SET(status); -MCE_INJECT_SET(misc); -MCE_INJECT_SET(addr); -MCE_INJECT_SET(synd); - -#define MCE_INJECT_GET(reg) \ -static int inj_##reg##_get(void *data, u64 *val) \ -{ \ - struct mce *m = (struct mce *)data; \ - \ - *val = m->reg; \ - return 0; \ -} - -MCE_INJECT_GET(status); -MCE_INJECT_GET(misc); -MCE_INJECT_GET(addr); -MCE_INJECT_GET(synd); - -DEFINE_SIMPLE_ATTRIBUTE(status_fops, inj_status_get, inj_status_set, "%llx\n"); -DEFINE_SIMPLE_ATTRIBUTE(misc_fops, inj_misc_get, inj_misc_set, "%llx\n"); -DEFINE_SIMPLE_ATTRIBUTE(addr_fops, inj_addr_get, inj_addr_set, "%llx\n"); -DEFINE_SIMPLE_ATTRIBUTE(synd_fops, inj_synd_get, inj_synd_set, "%llx\n"); - -static void setup_inj_struct(struct mce *m) -{ - memset(m, 0, sizeof(struct mce)); - - m->cpuvendor = boot_cpu_data.x86_vendor; -} - -/* Update fake mce registers on current CPU. */ -static void inject_mce(struct mce *m) -{ - struct mce *i = &per_cpu(injectm, m->extcpu); - - /* Make sure no one reads partially written injectm */ - i->finished = 0; - mb(); - m->finished = 0; - /* First set the fields after finished */ - i->extcpu = m->extcpu; - mb(); - /* Now write record in order, finished last (except above) */ - memcpy(i, m, sizeof(struct mce)); - /* Finally activate it */ - mb(); - i->finished = 1; -} - -static void raise_poll(struct mce *m) -{ - unsigned long flags; - mce_banks_t b; - - memset(&b, 0xff, sizeof(mce_banks_t)); - local_irq_save(flags); - machine_check_poll(0, &b); - local_irq_restore(flags); - m->finished = 0; -} - -static void raise_exception(struct mce *m, struct pt_regs *pregs) -{ - struct pt_regs regs; - unsigned long flags; - - if (!pregs) { - memset(®s, 0, sizeof(struct pt_regs)); - regs.ip = m->ip; - regs.cs = m->cs; - pregs = ®s; - } - /* in mcheck exeception handler, irq will be disabled */ - local_irq_save(flags); - do_machine_check(pregs, 0); - local_irq_restore(flags); - m->finished = 0; -} - -static cpumask_var_t mce_inject_cpumask; -static DEFINE_MUTEX(mce_inject_mutex); - -static int mce_raise_notify(unsigned int cmd, struct pt_regs *regs) -{ - int cpu = smp_processor_id(); - struct mce *m = this_cpu_ptr(&injectm); - if (!cpumask_test_cpu(cpu, mce_inject_cpumask)) - return NMI_DONE; - cpumask_clear_cpu(cpu, mce_inject_cpumask); - if (m->inject_flags & MCJ_EXCEPTION) - raise_exception(m, regs); - else if (m->status) - raise_poll(m); - return NMI_HANDLED; -} - -static void mce_irq_ipi(void *info) -{ - int cpu = smp_processor_id(); - struct mce *m = this_cpu_ptr(&injectm); - - if (cpumask_test_cpu(cpu, mce_inject_cpumask) && - m->inject_flags & MCJ_EXCEPTION) { - cpumask_clear_cpu(cpu, mce_inject_cpumask); - raise_exception(m, NULL); - } -} - -/* Inject mce on current CPU */ -static int raise_local(void) -{ - struct mce *m = this_cpu_ptr(&injectm); - int context = MCJ_CTX(m->inject_flags); - int ret = 0; - int cpu = m->extcpu; - - if (m->inject_flags & MCJ_EXCEPTION) { - pr_info("Triggering MCE exception on CPU %d\n", cpu); - switch (context) { - case MCJ_CTX_IRQ: - /* - * Could do more to fake interrupts like - * calling irq_enter, but the necessary - * machinery isn't exported currently. - */ - /*FALL THROUGH*/ - case MCJ_CTX_PROCESS: - raise_exception(m, NULL); - break; - default: - pr_info("Invalid MCE context\n"); - ret = -EINVAL; - } - pr_info("MCE exception done on CPU %d\n", cpu); - } else if (m->status) { - pr_info("Starting machine check poll CPU %d\n", cpu); - raise_poll(m); - mce_notify_irq(); - pr_info("Machine check poll done on CPU %d\n", cpu); - } else - m->finished = 0; - - return ret; -} - -static void __maybe_unused raise_mce(struct mce *m) -{ - int context = MCJ_CTX(m->inject_flags); - - inject_mce(m); - - if (context == MCJ_CTX_RANDOM) - return; - - if (m->inject_flags & (MCJ_IRQ_BROADCAST | MCJ_NMI_BROADCAST)) { - unsigned long start; - int cpu; - - get_online_cpus(); - cpumask_copy(mce_inject_cpumask, cpu_online_mask); - cpumask_clear_cpu(get_cpu(), mce_inject_cpumask); - for_each_online_cpu(cpu) { - struct mce *mcpu = &per_cpu(injectm, cpu); - if (!mcpu->finished || - MCJ_CTX(mcpu->inject_flags) != MCJ_CTX_RANDOM) - cpumask_clear_cpu(cpu, mce_inject_cpumask); - } - if (!cpumask_empty(mce_inject_cpumask)) { - if (m->inject_flags & MCJ_IRQ_BROADCAST) { - /* - * don't wait because mce_irq_ipi is necessary - * to be sync with following raise_local - */ - preempt_disable(); - smp_call_function_many(mce_inject_cpumask, - mce_irq_ipi, NULL, 0); - preempt_enable(); - } else if (m->inject_flags & MCJ_NMI_BROADCAST) - apic->send_IPI_mask(mce_inject_cpumask, - NMI_VECTOR); - } - start = jiffies; - while (!cpumask_empty(mce_inject_cpumask)) { - if (!time_before(jiffies, start + 2*HZ)) { - pr_err("Timeout waiting for mce inject %lx\n", - *cpumask_bits(mce_inject_cpumask)); - break; - } - cpu_relax(); - } - raise_local(); - put_cpu(); - put_online_cpus(); - } else { - preempt_disable(); - raise_local(); - preempt_enable(); - } -} - -static int mce_inject_raise(struct notifier_block *nb, unsigned long val, - void *data) -{ - struct mce *m = (struct mce *)data; - - if (!m) - return NOTIFY_DONE; - - mutex_lock(&mce_inject_mutex); - raise_mce(m); - mutex_unlock(&mce_inject_mutex); - - return NOTIFY_DONE; -} - -static struct notifier_block inject_nb = { - .notifier_call = mce_inject_raise, -}; - -/* - * Caller needs to be make sure this cpu doesn't disappear - * from under us, i.e.: get_cpu/put_cpu. - */ -static int toggle_hw_mce_inject(unsigned int cpu, bool enable) -{ - u32 l, h; - int err; - - err = rdmsr_on_cpu(cpu, MSR_K7_HWCR, &l, &h); - if (err) { - pr_err("%s: error reading HWCR\n", __func__); - return err; - } - - enable ? (l |= BIT(18)) : (l &= ~BIT(18)); - - err = wrmsr_on_cpu(cpu, MSR_K7_HWCR, l, h); - if (err) - pr_err("%s: error writing HWCR\n", __func__); - - return err; -} - -static int __set_inj(const char *buf) -{ - int i; - - for (i = 0; i < N_INJ_TYPES; i++) { - if (!strncmp(flags_options[i], buf, strlen(flags_options[i]))) { - inj_type = i; - return 0; - } - } - return -EINVAL; -} - -static ssize_t flags_read(struct file *filp, char __user *ubuf, - size_t cnt, loff_t *ppos) -{ - char buf[MAX_FLAG_OPT_SIZE]; - int n; - - n = sprintf(buf, "%s\n", flags_options[inj_type]); - - return simple_read_from_buffer(ubuf, cnt, ppos, buf, n); -} - -static ssize_t flags_write(struct file *filp, const char __user *ubuf, - size_t cnt, loff_t *ppos) -{ - char buf[MAX_FLAG_OPT_SIZE], *__buf; - int err; - - if (cnt > MAX_FLAG_OPT_SIZE) - return -EINVAL; - - if (copy_from_user(&buf, ubuf, cnt)) - return -EFAULT; - - buf[cnt - 1] = 0; - - /* strip whitespace */ - __buf = strstrip(buf); - - err = __set_inj(__buf); - if (err) { - pr_err("%s: Invalid flags value: %s\n", __func__, __buf); - return err; - } - - *ppos += cnt; - - return cnt; -} - -static const struct file_operations flags_fops = { - .read = flags_read, - .write = flags_write, - .llseek = generic_file_llseek, -}; - -/* - * On which CPU to inject? - */ -MCE_INJECT_GET(extcpu); - -static int inj_extcpu_set(void *data, u64 val) -{ - struct mce *m = (struct mce *)data; - - if (val >= nr_cpu_ids || !cpu_online(val)) { - pr_err("%s: Invalid CPU: %llu\n", __func__, val); - return -EINVAL; - } - m->extcpu = val; - return 0; -} - -DEFINE_SIMPLE_ATTRIBUTE(extcpu_fops, inj_extcpu_get, inj_extcpu_set, "%llu\n"); - -static void trigger_mce(void *info) -{ - asm volatile("int $18"); -} - -static void trigger_dfr_int(void *info) -{ - asm volatile("int %0" :: "i" (DEFERRED_ERROR_VECTOR)); -} - -static void trigger_thr_int(void *info) -{ - asm volatile("int %0" :: "i" (THRESHOLD_APIC_VECTOR)); -} - -static u32 get_nbc_for_node(int node_id) -{ - struct cpuinfo_x86 *c = &boot_cpu_data; - u32 cores_per_node; - - cores_per_node = (c->x86_max_cores * smp_num_siblings) / amd_get_nodes_per_socket(); - - return cores_per_node * node_id; -} - -static void toggle_nb_mca_mst_cpu(u16 nid) -{ - struct amd_northbridge *nb; - struct pci_dev *F3; - u32 val; - int err; - - nb = node_to_amd_nb(nid); - if (!nb) - return; - - F3 = nb->misc; - if (!F3) - return; - - err = pci_read_config_dword(F3, NBCFG, &val); - if (err) { - pr_err("%s: Error reading F%dx%03x.\n", - __func__, PCI_FUNC(F3->devfn), NBCFG); - return; - } - - if (val & BIT(27)) - return; - - pr_err("%s: Set D18F3x44[NbMcaToMstCpuEn] which BIOS hasn't done.\n", - __func__); - - val |= BIT(27); - err = pci_write_config_dword(F3, NBCFG, val); - if (err) - pr_err("%s: Error writing F%dx%03x.\n", - __func__, PCI_FUNC(F3->devfn), NBCFG); -} - -static void prepare_msrs(void *info) -{ - struct mce m = *(struct mce *)info; - u8 b = m.bank; - - wrmsrl(MSR_IA32_MCG_STATUS, m.mcgstatus); - - if (boot_cpu_has(X86_FEATURE_SMCA)) { - if (m.inject_flags == DFR_INT_INJ) { - wrmsrl(MSR_AMD64_SMCA_MCx_DESTAT(b), m.status); - wrmsrl(MSR_AMD64_SMCA_MCx_DEADDR(b), m.addr); - } else { - wrmsrl(MSR_AMD64_SMCA_MCx_STATUS(b), m.status); - wrmsrl(MSR_AMD64_SMCA_MCx_ADDR(b), m.addr); - } - - wrmsrl(MSR_AMD64_SMCA_MCx_MISC(b), m.misc); - wrmsrl(MSR_AMD64_SMCA_MCx_SYND(b), m.synd); - } else { - wrmsrl(MSR_IA32_MCx_STATUS(b), m.status); - wrmsrl(MSR_IA32_MCx_ADDR(b), m.addr); - wrmsrl(MSR_IA32_MCx_MISC(b), m.misc); - } -} - -static void do_inject(void) -{ - u64 mcg_status = 0; - unsigned int cpu = i_mce.extcpu; - u8 b = i_mce.bank; - - rdtscll(i_mce.tsc); - - if (i_mce.misc) - i_mce.status |= MCI_STATUS_MISCV; - - if (i_mce.synd) - i_mce.status |= MCI_STATUS_SYNDV; - - if (inj_type == SW_INJ) { - mce_inject_log(&i_mce); - return; - } - - /* prep MCE global settings for the injection */ - mcg_status = MCG_STATUS_MCIP | MCG_STATUS_EIPV; - - if (!(i_mce.status & MCI_STATUS_PCC)) - mcg_status |= MCG_STATUS_RIPV; - - /* - * Ensure necessary status bits for deferred errors: - * - MCx_STATUS[Deferred]: make sure it is a deferred error - * - MCx_STATUS[UC] cleared: deferred errors are _not_ UC - */ - if (inj_type == DFR_INT_INJ) { - i_mce.status |= MCI_STATUS_DEFERRED; - i_mce.status |= (i_mce.status & ~MCI_STATUS_UC); - } - - /* - * For multi node CPUs, logging and reporting of bank 4 errors happens - * only on the node base core. Refer to D18F3x44[NbMcaToMstCpuEn] for - * Fam10h and later BKDGs. - */ - if (static_cpu_has(X86_FEATURE_AMD_DCM) && - b == 4 && - boot_cpu_data.x86 < 0x17) { - toggle_nb_mca_mst_cpu(amd_get_nb_id(cpu)); - cpu = get_nbc_for_node(amd_get_nb_id(cpu)); - } - - get_online_cpus(); - if (!cpu_online(cpu)) - goto err; - - toggle_hw_mce_inject(cpu, true); - - i_mce.mcgstatus = mcg_status; - i_mce.inject_flags = inj_type; - smp_call_function_single(cpu, prepare_msrs, &i_mce, 0); - - toggle_hw_mce_inject(cpu, false); - - switch (inj_type) { - case DFR_INT_INJ: - smp_call_function_single(cpu, trigger_dfr_int, NULL, 0); - break; - case THR_INT_INJ: - smp_call_function_single(cpu, trigger_thr_int, NULL, 0); - break; - default: - smp_call_function_single(cpu, trigger_mce, NULL, 0); - } - -err: - put_online_cpus(); - -} - -/* - * This denotes into which bank we're injecting and triggers - * the injection, at the same time. - */ -static int inj_bank_set(void *data, u64 val) -{ - struct mce *m = (struct mce *)data; - - if (val >= n_banks) { - pr_err("Non-existent MCE bank: %llu\n", val); - return -EINVAL; - } - - m->bank = val; - do_inject(); - - return 0; -} - -MCE_INJECT_GET(bank); - -DEFINE_SIMPLE_ATTRIBUTE(bank_fops, inj_bank_get, inj_bank_set, "%llu\n"); - -static const char readme_msg[] = -"Description of the files and their usages:\n" -"\n" -"Note1: i refers to the bank number below.\n" -"Note2: See respective BKDGs for the exact bit definitions of the files below\n" -"as they mirror the hardware registers.\n" -"\n" -"status:\t Set MCi_STATUS: the bits in that MSR control the error type and\n" -"\t attributes of the error which caused the MCE.\n" -"\n" -"misc:\t Set MCi_MISC: provide auxiliary info about the error. It is mostly\n" -"\t used for error thresholding purposes and its validity is indicated by\n" -"\t MCi_STATUS[MiscV].\n" -"\n" -"synd:\t Set MCi_SYND: provide syndrome info about the error. Only valid on\n" -"\t Scalable MCA systems, and its validity is indicated by MCi_STATUS[SyndV].\n" -"\n" -"addr:\t Error address value to be written to MCi_ADDR. Log address information\n" -"\t associated with the error.\n" -"\n" -"cpu:\t The CPU to inject the error on.\n" -"\n" -"bank:\t Specify the bank you want to inject the error into: the number of\n" -"\t banks in a processor varies and is family/model-specific, therefore, the\n" -"\t supplied value is sanity-checked. Setting the bank value also triggers the\n" -"\t injection.\n" -"\n" -"flags:\t Injection type to be performed. Writing to this file will trigger a\n" -"\t real machine check, an APIC interrupt or invoke the error decoder routines\n" -"\t for AMD processors.\n" -"\n" -"\t Allowed error injection types:\n" -"\t - \"sw\": Software error injection. Decode error to a human-readable \n" -"\t format only. Safe to use.\n" -"\t - \"hw\": Hardware error injection. Causes the #MC exception handler to \n" -"\t handle the error. Be warned: might cause system panic if MCi_STATUS[PCC] \n" -"\t is set. Therefore, consider setting (debugfs_mountpoint)/mce/fake_panic \n" -"\t before injecting.\n" -"\t - \"df\": Trigger APIC interrupt for Deferred error. Causes deferred \n" -"\t error APIC interrupt handler to handle the error if the feature is \n" -"\t is present in hardware. \n" -"\t - \"th\": Trigger APIC interrupt for Threshold errors. Causes threshold \n" -"\t APIC interrupt handler to handle the error. \n" -"\n"; - -static ssize_t -inj_readme_read(struct file *filp, char __user *ubuf, - size_t cnt, loff_t *ppos) -{ - return simple_read_from_buffer(ubuf, cnt, ppos, - readme_msg, strlen(readme_msg)); -} - -static const struct file_operations readme_fops = { - .read = inj_readme_read, -}; - -static struct dfs_node { - char *name; - struct dentry *d; - const struct file_operations *fops; - umode_t perm; -} dfs_fls[] = { - { .name = "status", .fops = &status_fops, .perm = S_IRUSR | S_IWUSR }, - { .name = "misc", .fops = &misc_fops, .perm = S_IRUSR | S_IWUSR }, - { .name = "addr", .fops = &addr_fops, .perm = S_IRUSR | S_IWUSR }, - { .name = "synd", .fops = &synd_fops, .perm = S_IRUSR | S_IWUSR }, - { .name = "bank", .fops = &bank_fops, .perm = S_IRUSR | S_IWUSR }, - { .name = "flags", .fops = &flags_fops, .perm = S_IRUSR | S_IWUSR }, - { .name = "cpu", .fops = &extcpu_fops, .perm = S_IRUSR | S_IWUSR }, - { .name = "README", .fops = &readme_fops, .perm = S_IRUSR | S_IRGRP | S_IROTH }, -}; - -static int __init debugfs_init(void) -{ - unsigned int i; - u64 cap; - - rdmsrl(MSR_IA32_MCG_CAP, cap); - n_banks = cap & MCG_BANKCNT_MASK; - - dfs_inj = debugfs_create_dir("mce-inject", NULL); - if (!dfs_inj) - return -EINVAL; - - for (i = 0; i < ARRAY_SIZE(dfs_fls); i++) { - dfs_fls[i].d = debugfs_create_file(dfs_fls[i].name, - dfs_fls[i].perm, - dfs_inj, - &i_mce, - dfs_fls[i].fops); - - if (!dfs_fls[i].d) - goto err_dfs_add; - } - - return 0; - -err_dfs_add: - while (i-- > 0) - debugfs_remove(dfs_fls[i].d); - - debugfs_remove(dfs_inj); - dfs_inj = NULL; - - return -ENODEV; -} - -static int __init inject_init(void) -{ - int err; - - if (!alloc_cpumask_var(&mce_inject_cpumask, GFP_KERNEL)) - return -ENOMEM; - - err = debugfs_init(); - if (err) { - free_cpumask_var(mce_inject_cpumask); - return err; - } - - register_nmi_handler(NMI_LOCAL, mce_raise_notify, 0, "mce_notify"); - mce_register_injector_chain(&inject_nb); - - setup_inj_struct(&i_mce); - - pr_info("Machine check injector initialized\n"); - - return 0; -} - -static void __exit inject_exit(void) -{ - - mce_unregister_injector_chain(&inject_nb); - unregister_nmi_handler(NMI_LOCAL, "mce_notify"); - - debugfs_remove_recursive(dfs_inj); - dfs_inj = NULL; - - memset(&dfs_fls, 0, sizeof(dfs_fls)); - - free_cpumask_var(mce_inject_cpumask); -} - -module_init(inject_init); -module_exit(inject_exit); -MODULE_LICENSE("GPL"); |