[PATCH 1/4] x86/mce: Merge mce_amd_inj into mce-inject

From: Borislav Petkov
Date: Tue Jun 06 2017 - 05:34:10 EST


From: Borislav Petkov <bp@xxxxxxx>

Reuse mce_amd_inj's debugfs interface so that mce-inject can
benefit from it too. The old functionality is still preserved under
CONFIG_X86_MCELOG_LEGACY.

Signed-off-by: Borislav Petkov <bp@xxxxxxx>
---
arch/x86/Kconfig | 2 +-
arch/x86/Makefile | 2 -
arch/x86/include/asm/processor.h | 5 +
arch/x86/kernel/cpu/mcheck/mce-inject.c | 540 +++++++++++++++++++++++++++++++-
arch/x86/ras/Kconfig | 11 -
arch/x86/ras/Makefile | 2 -
arch/x86/ras/mce_amd_inj.c | 492 -----------------------------
7 files changed, 531 insertions(+), 523 deletions(-)
delete mode 100644 arch/x86/ras/Makefile
delete mode 100644 arch/x86/ras/mce_amd_inj.c

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index cd18994a9555..e42875b2d905 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1082,7 +1082,7 @@ config X86_MCE_THRESHOLD
def_bool y

config X86_MCE_INJECT
- depends on X86_MCE && X86_LOCAL_APIC && X86_MCELOG_LEGACY
+ depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
tristate "Machine check injector support"
---help---
Provide support for injecting machine checks for testing purposes.
diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index 5851411e60fb..c80c0192789c 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -257,8 +257,6 @@ drivers-$(CONFIG_PM) += arch/x86/power/

drivers-$(CONFIG_FB) += arch/x86/video/

-drivers-$(CONFIG_RAS) += arch/x86/ras/
-
####
# boot loader support. Several targets are kept for legacy purposes

diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 3cada998a402..71f6fba95aa6 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -901,8 +901,13 @@ static inline int mpx_disable_management(void)
}
#endif /* CONFIG_X86_INTEL_MPX */

+#ifdef CONFIG_CPU_SUP_AMD
extern u16 amd_get_nb_id(int cpu);
extern u32 amd_get_nodes_per_socket(void);
+#else
+static inline u16 amd_get_nb_id(int cpu) { return 0; }
+static inline u32 amd_get_nodes_per_socket(void) { return 0; }
+#endif

static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)
{
diff --git a/arch/x86/kernel/cpu/mcheck/mce-inject.c b/arch/x86/kernel/cpu/mcheck/mce-inject.c
index 99165b206df3..45b81c84ed1e 100644
--- a/arch/x86/kernel/cpu/mcheck/mce-inject.c
+++ b/arch/x86/kernel/cpu/mcheck/mce-inject.c
@@ -10,23 +10,108 @@
* 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@xxxxxxxxx>
+ * Advanced Micro Devices Inc.
*/
-#include <linux/uaccess.h>
-#include <linux/module.h>
-#include <linux/timer.h>
-#include <linux/kernel.h>
-#include <linux/string.h>
+
+#include <linux/cpu.h>
+#include <linux/debugfs.h>
+#include <linux/device.h>
#include <linux/fs.h>
-#include <linux/preempt.h>
-#include <linux/smp.h>
-#include <linux/notifier.h>
+#include <linux/gfp.h>
#include <linux/kdebug.h>
-#include <linux/cpu.h>
+#include <linux/kernel.h>
+#include <linux/kobject.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/pci.h>
+#include <linux/preempt.h>
#include <linux/sched.h>
-#include <linux/gfp.h>
-#include <asm/mce.h>
+#include <linux/smp.h>
+#include <linux/string.h>
+#include <linux/timer.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");

/* Update fake mce registers on current CPU. */
static void inject_mce(struct mce *m)
@@ -143,7 +228,7 @@ static int raise_local(void)
return ret;
}

-static void raise_mce(struct mce *m)
+static void __maybe_unused raise_mce(struct mce *m)
{
int context = MCJ_CTX(m->inject_flags);

@@ -198,6 +283,7 @@ static void raise_mce(struct mce *m)
}
}

+#ifdef CONFIG_X86_MCELOG_LEGACY
/* Error injection interface */
static ssize_t mce_write(struct file *filp, const char __user *ubuf,
size_t usize, loff_t *off)
@@ -232,21 +318,445 @@ static ssize_t mce_write(struct file *filp, const char __user *ubuf,
mutex_unlock(&mce_inject_mutex);
return usize;
}
+#endif /* CONFIG_X86_MCELOG_LEGACY */
+
+/*
+ * 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 inject_init(void)
{
+ int err;
+
if (!alloc_cpumask_var(&mce_inject_cpumask, GFP_KERNEL))
return -ENOMEM;
+
+#ifdef CONFIG_X86_MCELOG_LEGACY
+ register_mce_write_callback(mce_write);
+#endif
+
+ register_nmi_handler(NMI_LOCAL, mce_raise_notify, 0, "mce_notify");
+
+ err = debugfs_init();
+ if (err) {
+ free_cpumask_var(mce_inject_cpumask);
+ return err;
+ }
+
pr_info("Machine check injector initialized\n");
- register_mce_write_callback(mce_write);
- register_nmi_handler(NMI_LOCAL, mce_raise_notify, 0,
- "mce_notify");
+
return 0;
}

module_init(inject_init);
+
/*
* Cannot tolerate unloading currently because we cannot
* guarantee all openers of mce_chrdev will get a reference to us.
*/
+#ifndef CONFIG_X86_MCELOG_LEGACY
+static void __exit inject_exit(void)
+{
+
+ debugfs_remove_recursive(dfs_inj);
+ dfs_inj = NULL;
+
+ memset(&dfs_fls, 0, sizeof(dfs_fls));
+
+ unregister_nmi_handler(NMI_LOCAL, "mce_notify");
+
+ free_cpumask_var(mce_inject_cpumask);
+}
+
+module_exit(inject_exit);
+#endif
+
MODULE_LICENSE("GPL");
diff --git a/arch/x86/ras/Kconfig b/arch/x86/ras/Kconfig
index 2a2d89d39af6..bb026699ad19 100644
--- a/arch/x86/ras/Kconfig
+++ b/arch/x86/ras/Kconfig
@@ -1,13 +1,3 @@
-config MCE_AMD_INJ
- tristate "Simple MCE injection interface for AMD processors"
- depends on RAS && X86_MCE && DEBUG_FS && AMD_NB
- default n
- help
- This is a simple debugfs interface to inject MCEs and test different
- aspects of the MCE handling code.
-
- WARNING: Do not even assume this interface is staying stable!
-
config RAS_CEC
bool "Correctable Errors Collector"
depends on X86_MCE && MEMORY_FAILURE && DEBUG_FS
@@ -20,4 +10,3 @@ config RAS_CEC

Bear in mind that this is absolutely useless if your platform doesn't
have ECC DIMMs and doesn't have DRAM ECC checking enabled in the BIOS.
-
diff --git a/arch/x86/ras/Makefile b/arch/x86/ras/Makefile
deleted file mode 100644
index 5f94546db280..000000000000
--- a/arch/x86/ras/Makefile
+++ /dev/null
@@ -1,2 +0,0 @@
-obj-$(CONFIG_MCE_AMD_INJ) += mce_amd_inj.o
-
diff --git a/arch/x86/ras/mce_amd_inj.c b/arch/x86/ras/mce_amd_inj.c
deleted file mode 100644
index 8730c2882fff..000000000000
--- a/arch/x86/ras/mce_amd_inj.c
+++ /dev/null
@@ -1,492 +0,0 @@
-/*
- * 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) 2010-15: Borislav Petkov <bp@xxxxxxxxx>
- * Advanced Micro Devices Inc.
- */
-
-#include <linux/kobject.h>
-#include <linux/debugfs.h>
-#include <linux/device.h>
-#include <linux/module.h>
-#include <linux/cpu.h>
-#include <linux/string.h>
-#include <linux/uaccess.h>
-#include <linux/pci.h>
-
-#include <asm/mce.h>
-#include <asm/smp.h>
-#include <asm/amd_nb.h>
-#include <asm/irq_vectors.h>
-
-#include "../kernel/cpu/mcheck/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");
-
-/*
- * 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 pci_dev *F3 = node_to_amd_nb(nid)->misc;
- u32 val;
- int err;
-
- 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 init_mce_inject(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 void __exit exit_mce_inject(void)
-{
-
- debugfs_remove_recursive(dfs_inj);
- dfs_inj = NULL;
-
- memset(&dfs_fls, 0, sizeof(dfs_fls));
-}
-module_init(init_mce_inject);
-module_exit(exit_mce_inject);
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Borislav Petkov <bp@xxxxxxxxx>");
-MODULE_AUTHOR("AMD Inc.");
-MODULE_DESCRIPTION("MCE injection facility for RAS testing");
--
2.13.0