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Diffstat (limited to 'arch/x86/kernel/cpu/mcheck/mce.c')
-rw-r--r--arch/x86/kernel/cpu/mcheck/mce.c357
1 files changed, 186 insertions, 171 deletions
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index 466f47301334..36d2696c9563 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -42,6 +42,7 @@
#include <linux/irq_work.h>
#include <linux/export.h>
#include <linux/jump_label.h>
+#include <linux/set_memory.h>
#include <asm/intel-family.h>
#include <asm/processor.h>
@@ -50,7 +51,6 @@
#include <asm/mce.h>
#include <asm/msr.h>
#include <asm/reboot.h>
-#include <asm/set_memory.h>
#include "mce-internal.h"
@@ -108,10 +108,6 @@ static struct irq_work mce_irq_work;
static void (*quirk_no_way_out)(int bank, struct mce *m, struct pt_regs *regs);
-#ifndef mce_unmap_kpfn
-static void mce_unmap_kpfn(unsigned long pfn);
-#endif
-
/*
* CPU/chipset specific EDAC code can register a notifier call here to print
* MCE errors in a human-readable form.
@@ -123,8 +119,8 @@ void mce_setup(struct mce *m)
{
memset(m, 0, sizeof(struct mce));
m->cpu = m->extcpu = smp_processor_id();
- /* We hope get_seconds stays lockless */
- m->time = get_seconds();
+ /* need the internal __ version to avoid deadlocks */
+ m->time = __ktime_get_real_seconds();
m->cpuvendor = boot_cpu_data.x86_vendor;
m->cpuid = cpuid_eax(1);
m->socketid = cpu_data(m->extcpu).phys_proc_id;
@@ -273,7 +269,9 @@ static void __print_mce(struct mce *m)
static void print_mce(struct mce *m)
{
__print_mce(m);
- pr_emerg_ratelimited(HW_ERR "Run the above through 'mcelog --ascii'\n");
+
+ if (m->cpuvendor != X86_VENDOR_AMD && m->cpuvendor != X86_VENDOR_HYGON)
+ pr_emerg_ratelimited(HW_ERR "Run the above through 'mcelog --ascii'\n");
}
#define PANIC_TIMEOUT 5 /* 5 seconds */
@@ -487,7 +485,7 @@ static void mce_report_event(struct pt_regs *regs)
* be somewhat complicated (e.g. segment offset would require an instruction
* parser). So only support physical addresses up to page granuality for now.
*/
-static int mce_usable_address(struct mce *m)
+int mce_usable_address(struct mce *m)
{
if (!(m->status & MCI_STATUS_ADDRV))
return 0;
@@ -507,12 +505,13 @@ static int mce_usable_address(struct mce *m)
return 1;
}
+EXPORT_SYMBOL_GPL(mce_usable_address);
bool mce_is_memory_error(struct mce *m)
{
- if (m->cpuvendor == X86_VENDOR_AMD) {
+ if (m->cpuvendor == X86_VENDOR_AMD ||
+ m->cpuvendor == X86_VENDOR_HYGON) {
return amd_mce_is_memory_error(m);
-
} else if (m->cpuvendor == X86_VENDOR_INTEL) {
/*
* Intel SDM Volume 3B - 15.9.2 Compound Error Codes
@@ -536,16 +535,20 @@ bool mce_is_memory_error(struct mce *m)
}
EXPORT_SYMBOL_GPL(mce_is_memory_error);
-static bool mce_is_correctable(struct mce *m)
+bool mce_is_correctable(struct mce *m)
{
if (m->cpuvendor == X86_VENDOR_AMD && m->status & MCI_STATUS_DEFERRED)
return false;
+ if (m->cpuvendor == X86_VENDOR_HYGON && m->status & MCI_STATUS_DEFERRED)
+ return false;
+
if (m->status & MCI_STATUS_UC)
return false;
return true;
}
+EXPORT_SYMBOL_GPL(mce_is_correctable);
static bool cec_add_mce(struct mce *m)
{
@@ -600,7 +603,7 @@ static int srao_decode_notifier(struct notifier_block *nb, unsigned long val,
if (mce_usable_address(mce) && (mce->severity == MCE_AO_SEVERITY)) {
pfn = mce->addr >> PAGE_SHIFT;
if (!memory_failure(pfn, 0))
- mce_unmap_kpfn(pfn);
+ set_mce_nospec(pfn);
}
return NOTIFY_OK;
@@ -770,23 +773,25 @@ EXPORT_SYMBOL_GPL(machine_check_poll);
static int mce_no_way_out(struct mce *m, char **msg, unsigned long *validp,
struct pt_regs *regs)
{
- int i, ret = 0;
char *tmp;
+ int i;
for (i = 0; i < mca_cfg.banks; i++) {
m->status = mce_rdmsrl(msr_ops.status(i));
- if (m->status & MCI_STATUS_VAL) {
- __set_bit(i, validp);
- if (quirk_no_way_out)
- quirk_no_way_out(i, m, regs);
- }
+ if (!(m->status & MCI_STATUS_VAL))
+ continue;
+
+ __set_bit(i, validp);
+ if (quirk_no_way_out)
+ quirk_no_way_out(i, m, regs);
if (mce_severity(m, mca_cfg.tolerant, &tmp, true) >= MCE_PANIC_SEVERITY) {
+ mce_read_aux(m, i);
*msg = tmp;
- ret = 1;
+ return 1;
}
}
- return ret;
+ return 0;
}
/*
@@ -1068,49 +1073,104 @@ static int do_memory_failure(struct mce *m)
if (ret)
pr_err("Memory error not recovered");
else
- mce_unmap_kpfn(m->addr >> PAGE_SHIFT);
+ set_mce_nospec(m->addr >> PAGE_SHIFT);
return ret;
}
-#ifndef mce_unmap_kpfn
-static void mce_unmap_kpfn(unsigned long pfn)
-{
- unsigned long decoy_addr;
-
- /*
- * Unmap this page from the kernel 1:1 mappings to make sure
- * we don't log more errors because of speculative access to
- * the page.
- * We would like to just call:
- * set_memory_np((unsigned long)pfn_to_kaddr(pfn), 1);
- * but doing that would radically increase the odds of a
- * speculative access to the poison page because we'd have
- * the virtual address of the kernel 1:1 mapping sitting
- * around in registers.
- * Instead we get tricky. We create a non-canonical address
- * that looks just like the one we want, but has bit 63 flipped.
- * This relies on set_memory_np() not checking whether we passed
- * a legal address.
- */
/*
- * Build time check to see if we have a spare virtual bit. Don't want
- * to leave this until run time because most developers don't have a
- * system that can exercise this code path. This will only become a
- * problem if/when we move beyond 5-level page tables.
+ * Cases where we avoid rendezvous handler timeout:
+ * 1) If this CPU is offline.
*
- * Hard code "9" here because cpp doesn't grok ilog2(PTRS_PER_PGD)
+ * 2) If crashing_cpu was set, e.g. we're entering kdump and we need to
+ * skip those CPUs which remain looping in the 1st kernel - see
+ * crash_nmi_callback().
+ *
+ * Note: there still is a small window between kexec-ing and the new,
+ * kdump kernel establishing a new #MC handler where a broadcasted MCE
+ * might not get handled properly.
*/
-#if PGDIR_SHIFT + 9 < 63
- decoy_addr = (pfn << PAGE_SHIFT) + (PAGE_OFFSET ^ BIT(63));
-#else
-#error "no unused virtual bit available"
-#endif
+static bool __mc_check_crashing_cpu(int cpu)
+{
+ if (cpu_is_offline(cpu) ||
+ (crashing_cpu != -1 && crashing_cpu != cpu)) {
+ u64 mcgstatus;
- if (set_memory_np(decoy_addr, 1))
- pr_warn("Could not invalidate pfn=0x%lx from 1:1 map\n", pfn);
+ mcgstatus = mce_rdmsrl(MSR_IA32_MCG_STATUS);
+ if (mcgstatus & MCG_STATUS_RIPV) {
+ mce_wrmsrl(MSR_IA32_MCG_STATUS, 0);
+ return true;
+ }
+ }
+ return false;
+}
+
+static void __mc_scan_banks(struct mce *m, struct mce *final,
+ unsigned long *toclear, unsigned long *valid_banks,
+ int no_way_out, int *worst)
+{
+ struct mca_config *cfg = &mca_cfg;
+ int severity, i;
+
+ for (i = 0; i < cfg->banks; i++) {
+ __clear_bit(i, toclear);
+ if (!test_bit(i, valid_banks))
+ continue;
+
+ if (!mce_banks[i].ctl)
+ continue;
+
+ m->misc = 0;
+ m->addr = 0;
+ m->bank = i;
+
+ m->status = mce_rdmsrl(msr_ops.status(i));
+ if (!(m->status & MCI_STATUS_VAL))
+ continue;
+
+ /*
+ * Corrected or non-signaled errors are handled by
+ * machine_check_poll(). Leave them alone, unless this panics.
+ */
+ if (!(m->status & (cfg->ser ? MCI_STATUS_S : MCI_STATUS_UC)) &&
+ !no_way_out)
+ continue;
+
+ /* Set taint even when machine check was not enabled. */
+ add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE);
+
+ severity = mce_severity(m, cfg->tolerant, NULL, true);
+
+ /*
+ * When machine check was for corrected/deferred handler don't
+ * touch, unless we're panicking.
+ */
+ if ((severity == MCE_KEEP_SEVERITY ||
+ severity == MCE_UCNA_SEVERITY) && !no_way_out)
+ continue;
+
+ __set_bit(i, toclear);
+
+ /* Machine check event was not enabled. Clear, but ignore. */
+ if (severity == MCE_NO_SEVERITY)
+ continue;
+
+ mce_read_aux(m, i);
+
+ /* assuming valid severity level != 0 */
+ m->severity = severity;
+
+ mce_log(m);
+
+ if (severity > *worst) {
+ *final = *m;
+ *worst = severity;
+ }
+ }
+
+ /* mce_clear_state will clear *final, save locally for use later */
+ *m = *final;
}
-#endif
/*
* The actual machine check handler. This only handles real
@@ -1126,68 +1186,45 @@ static void mce_unmap_kpfn(unsigned long pfn)
*/
void do_machine_check(struct pt_regs *regs, long error_code)
{
+ DECLARE_BITMAP(valid_banks, MAX_NR_BANKS);
+ DECLARE_BITMAP(toclear, MAX_NR_BANKS);
struct mca_config *cfg = &mca_cfg;
+ int cpu = smp_processor_id();
+ char *msg = "Unknown";
struct mce m, *final;
- int i;
int worst = 0;
- int severity;
/*
* Establish sequential order between the CPUs entering the machine
* check handler.
*/
int order = -1;
+
/*
* If no_way_out gets set, there is no safe way to recover from this
* MCE. If mca_cfg.tolerant is cranked up, we'll try anyway.
*/
int no_way_out = 0;
+
/*
* If kill_it gets set, there might be a way to recover from this
* error.
*/
int kill_it = 0;
- DECLARE_BITMAP(toclear, MAX_NR_BANKS);
- DECLARE_BITMAP(valid_banks, MAX_NR_BANKS);
- char *msg = "Unknown";
/*
* MCEs are always local on AMD. Same is determined by MCG_STATUS_LMCES
* on Intel.
*/
int lmce = 1;
- int cpu = smp_processor_id();
- /*
- * Cases where we avoid rendezvous handler timeout:
- * 1) If this CPU is offline.
- *
- * 2) If crashing_cpu was set, e.g. we're entering kdump and we need to
- * skip those CPUs which remain looping in the 1st kernel - see
- * crash_nmi_callback().
- *
- * Note: there still is a small window between kexec-ing and the new,
- * kdump kernel establishing a new #MC handler where a broadcasted MCE
- * might not get handled properly.
- */
- if (cpu_is_offline(cpu) ||
- (crashing_cpu != -1 && crashing_cpu != cpu)) {
- u64 mcgstatus;
-
- mcgstatus = mce_rdmsrl(MSR_IA32_MCG_STATUS);
- if (mcgstatus & MCG_STATUS_RIPV) {
- mce_wrmsrl(MSR_IA32_MCG_STATUS, 0);
- return;
- }
- }
+ if (__mc_check_crashing_cpu(cpu))
+ return;
ist_enter(regs);
this_cpu_inc(mce_exception_count);
- if (!cfg->banks)
- goto out;
-
mce_gather_info(&m, regs);
m.tsc = rdtsc();
@@ -1215,75 +1252,20 @@ void do_machine_check(struct pt_regs *regs, long error_code)
lmce = m.mcgstatus & MCG_STATUS_LMCES;
/*
+ * Local machine check may already know that we have to panic.
+ * Broadcast machine check begins rendezvous in mce_start()
* Go through all banks in exclusion of the other CPUs. This way we
* don't report duplicated events on shared banks because the first one
- * to see it will clear it. If this is a Local MCE, then no need to
- * perform rendezvous.
+ * to see it will clear it.
*/
- if (!lmce)
+ if (lmce) {
+ if (no_way_out)
+ mce_panic("Fatal local machine check", &m, msg);
+ } else {
order = mce_start(&no_way_out);
-
- for (i = 0; i < cfg->banks; i++) {
- __clear_bit(i, toclear);
- if (!test_bit(i, valid_banks))
- continue;
- if (!mce_banks[i].ctl)
- continue;
-
- m.misc = 0;
- m.addr = 0;
- m.bank = i;
-
- m.status = mce_rdmsrl(msr_ops.status(i));
- if ((m.status & MCI_STATUS_VAL) == 0)
- continue;
-
- /*
- * Non uncorrected or non signaled errors are handled by
- * machine_check_poll. Leave them alone, unless this panics.
- */
- if (!(m.status & (cfg->ser ? MCI_STATUS_S : MCI_STATUS_UC)) &&
- !no_way_out)
- continue;
-
- /*
- * Set taint even when machine check was not enabled.
- */
- add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE);
-
- severity = mce_severity(&m, cfg->tolerant, NULL, true);
-
- /*
- * When machine check was for corrected/deferred handler don't
- * touch, unless we're panicing.
- */
- if ((severity == MCE_KEEP_SEVERITY ||
- severity == MCE_UCNA_SEVERITY) && !no_way_out)
- continue;
- __set_bit(i, toclear);
- if (severity == MCE_NO_SEVERITY) {
- /*
- * Machine check event was not enabled. Clear, but
- * ignore.
- */
- continue;
- }
-
- mce_read_aux(&m, i);
-
- /* assuming valid severity level != 0 */
- m.severity = severity;
-
- mce_log(&m);
-
- if (severity > worst) {
- *final = m;
- worst = severity;
- }
}
- /* mce_clear_state will clear *final, save locally for use later */
- m = *final;
+ __mc_scan_banks(&m, final, toclear, valid_banks, no_way_out, &worst);
if (!no_way_out)
mce_clear_state(toclear);
@@ -1297,12 +1279,17 @@ void do_machine_check(struct pt_regs *regs, long error_code)
no_way_out = worst >= MCE_PANIC_SEVERITY;
} else {
/*
- * Local MCE skipped calling mce_reign()
- * If we found a fatal error, we need to panic here.
+ * If there was a fatal machine check we should have
+ * already called mce_panic earlier in this function.
+ * Since we re-read the banks, we might have found
+ * something new. Check again to see if we found a
+ * fatal error. We call "mce_severity()" again to
+ * make sure we have the right "msg".
*/
- if (worst >= MCE_PANIC_SEVERITY && mca_cfg.tolerant < 3)
- mce_panic("Machine check from unknown source",
- NULL, NULL);
+ if (worst >= MCE_PANIC_SEVERITY && mca_cfg.tolerant < 3) {
+ mce_severity(&m, cfg->tolerant, &msg, true);
+ mce_panic("Local fatal machine check!", &m, msg);
+ }
}
/*
@@ -1317,7 +1304,7 @@ void do_machine_check(struct pt_regs *regs, long error_code)
if (worst > 0)
mce_report_event(regs);
mce_wrmsrl(MSR_IA32_MCG_STATUS, 0);
-out:
+
sync_core();
if (worst != MCE_AR_SEVERITY && !kill_it)
@@ -1333,7 +1320,7 @@ out:
local_irq_disable();
ist_end_non_atomic();
} else {
- if (!fixup_exception(regs, X86_TRAP_MC))
+ if (!fixup_exception(regs, X86_TRAP_MC, error_code, 0))
mce_panic("Failed kernel mode recovery", &m, NULL);
}
@@ -1467,7 +1454,7 @@ static int __mcheck_cpu_mce_banks_init(void)
int i;
u8 num_banks = mca_cfg.banks;
- mce_banks = kzalloc(num_banks * sizeof(struct mce_bank), GFP_KERNEL);
+ mce_banks = kcalloc(num_banks, sizeof(struct mce_bank), GFP_KERNEL);
if (!mce_banks)
return -ENOMEM;
@@ -1516,7 +1503,7 @@ static int __mcheck_cpu_cap_init(void)
mca_cfg.rip_msr = MSR_IA32_MCG_EIP;
if (cap & MCG_SER_P)
- mca_cfg.ser = true;
+ mca_cfg.ser = 1;
return 0;
}
@@ -1723,7 +1710,7 @@ static int __mcheck_cpu_ancient_init(struct cpuinfo_x86 *c)
*/
static void __mcheck_cpu_init_early(struct cpuinfo_x86 *c)
{
- if (c->x86_vendor == X86_VENDOR_AMD) {
+ if (c->x86_vendor == X86_VENDOR_AMD || c->x86_vendor == X86_VENDOR_HYGON) {
mce_flags.overflow_recov = !!cpu_has(c, X86_FEATURE_OVERFLOW_RECOV);
mce_flags.succor = !!cpu_has(c, X86_FEATURE_SUCCOR);
mce_flags.smca = !!cpu_has(c, X86_FEATURE_SMCA);
@@ -1737,6 +1724,21 @@ static void __mcheck_cpu_init_early(struct cpuinfo_x86 *c)
}
}
+static void mce_centaur_feature_init(struct cpuinfo_x86 *c)
+{
+ struct mca_config *cfg = &mca_cfg;
+
+ /*
+ * All newer Centaur CPUs support MCE broadcasting. Enable
+ * synchronization with a one second timeout.
+ */
+ if ((c->x86 == 6 && c->x86_model == 0xf && c->x86_stepping >= 0xe) ||
+ c->x86 > 6) {
+ if (cfg->monarch_timeout < 0)
+ cfg->monarch_timeout = USEC_PER_SEC;
+ }
+}
+
static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 *c)
{
switch (c->x86_vendor) {
@@ -1750,6 +1752,14 @@ static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 *c)
break;
}
+ case X86_VENDOR_HYGON:
+ mce_hygon_feature_init(c);
+ break;
+
+ case X86_VENDOR_CENTAUR:
+ mce_centaur_feature_init(c);
+ break;
+
default:
break;
}
@@ -1824,12 +1834,12 @@ void mcheck_cpu_init(struct cpuinfo_x86 *c)
return;
if (__mcheck_cpu_cap_init() < 0 || __mcheck_cpu_apply_quirks(c) < 0) {
- mca_cfg.disabled = true;
+ mca_cfg.disabled = 1;
return;
}
if (mce_gen_pool_init()) {
- mca_cfg.disabled = true;
+ mca_cfg.disabled = 1;
pr_emerg("Couldn't allocate MCE records pool!\n");
return;
}
@@ -1907,11 +1917,11 @@ static int __init mcheck_enable(char *str)
if (*str == '=')
str++;
if (!strcmp(str, "off"))
- cfg->disabled = true;
+ cfg->disabled = 1;
else if (!strcmp(str, "no_cmci"))
cfg->cmci_disabled = true;
else if (!strcmp(str, "no_lmce"))
- cfg->lmce_disabled = true;
+ cfg->lmce_disabled = 1;
else if (!strcmp(str, "dont_log_ce"))
cfg->dont_log_ce = true;
else if (!strcmp(str, "ignore_ce"))
@@ -1919,9 +1929,9 @@ static int __init mcheck_enable(char *str)
else if (!strcmp(str, "bootlog") || !strcmp(str, "nobootlog"))
cfg->bootlog = (str[0] == 'b');
else if (!strcmp(str, "bios_cmci_threshold"))
- cfg->bios_cmci_threshold = true;
+ cfg->bios_cmci_threshold = 1;
else if (!strcmp(str, "recovery"))
- cfg->recovery = true;
+ cfg->recovery = 1;
else if (isdigit(str[0])) {
if (get_option(&str, &cfg->tolerant) == 2)
get_option(&str, &(cfg->monarch_timeout));
@@ -1971,12 +1981,14 @@ static void mce_disable_error_reporting(void)
static void vendor_disable_error_reporting(void)
{
/*
- * Don't clear on Intel or AMD CPUs. Some of these MSRs are socket-wide.
+ * Don't clear on Intel or AMD or Hygon CPUs. Some of these MSRs
+ * are socket-wide.
* Disabling them for just a single offlined CPU is bad, since it will
* inhibit reporting for all shared resources on the socket like the
* last level cache (LLC), the integrated memory controller (iMC), etc.
*/
if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL ||
+ boot_cpu_data.x86_vendor == X86_VENDOR_HYGON ||
boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
return;
@@ -2145,9 +2157,6 @@ static ssize_t store_int_with_restart(struct device *s,
if (check_interval == old_check_interval)
return ret;
- if (check_interval < 1)
- check_interval = 1;
-
mutex_lock(&mce_sysfs_mutex);
mce_restart();
mutex_unlock(&mce_sysfs_mutex);
@@ -2208,7 +2217,7 @@ static int mce_device_create(unsigned int cpu)
if (dev)
return 0;
- dev = kzalloc(sizeof *dev, GFP_KERNEL);
+ dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return -ENOMEM;
dev->id = cpu;
@@ -2355,6 +2364,12 @@ static __init int mcheck_init_device(void)
{
int err;
+ /*
+ * Check if we have a spare virtual bit. This will only become
+ * a problem if/when we move beyond 5-level page tables.
+ */
+ MAYBE_BUILD_BUG_ON(__VIRTUAL_MASK_SHIFT >= 63);
+
if (!mce_available(&boot_cpu_data)) {
err = -EIO;
goto err_out;
@@ -2403,7 +2418,7 @@ device_initcall_sync(mcheck_init_device);
*/
static int __init mcheck_disable(char *str)
{
- mca_cfg.disabled = true;
+ mca_cfg.disabled = 1;
return 1;
}
__setup("nomce", mcheck_disable);
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