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Diffstat (limited to 'arch/x86/kernel/cpu/mcheck/mce.c')
-rw-r--r--arch/x86/kernel/cpu/mcheck/mce.c72
1 files changed, 52 insertions, 20 deletions
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index e535533d5ab8..df919ff103c3 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -53,9 +53,12 @@
static DEFINE_MUTEX(mce_chrdev_read_mutex);
#define rcu_dereference_check_mce(p) \
- rcu_dereference_index_check((p), \
- rcu_read_lock_sched_held() || \
- lockdep_is_held(&mce_chrdev_read_mutex))
+({ \
+ rcu_lockdep_assert(rcu_read_lock_sched_held() || \
+ lockdep_is_held(&mce_chrdev_read_mutex), \
+ "suspicious rcu_dereference_check_mce() usage"); \
+ smp_load_acquire(&(p)); \
+})
#define CREATE_TRACE_POINTS
#include <trace/events/mce.h>
@@ -708,6 +711,7 @@ static int mce_no_way_out(struct mce *m, char **msg, unsigned long *validp,
struct pt_regs *regs)
{
int i, ret = 0;
+ char *tmp;
for (i = 0; i < mca_cfg.banks; i++) {
m->status = mce_rdmsrl(MSR_IA32_MCx_STATUS(i));
@@ -716,9 +720,11 @@ static int mce_no_way_out(struct mce *m, char **msg, unsigned long *validp,
if (quirk_no_way_out)
quirk_no_way_out(i, m, regs);
}
- if (mce_severity(m, mca_cfg.tolerant, msg, true) >=
- MCE_PANIC_SEVERITY)
+
+ if (mce_severity(m, mca_cfg.tolerant, &tmp, true) >= MCE_PANIC_SEVERITY) {
+ *msg = tmp;
ret = 1;
+ }
}
return ret;
}
@@ -1047,6 +1053,7 @@ void do_machine_check(struct pt_regs *regs, long error_code)
char *msg = "Unknown";
u64 recover_paddr = ~0ull;
int flags = MF_ACTION_REQUIRED;
+ int lmce = 0;
prev_state = ist_enter(regs);
@@ -1074,11 +1081,20 @@ void do_machine_check(struct pt_regs *regs, long error_code)
kill_it = 1;
/*
- * Go through all the 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.
+ * Check if this MCE is signaled to only this logical processor
*/
- order = mce_start(&no_way_out);
+ if (m.mcgstatus & MCG_STATUS_LMCES)
+ lmce = 1;
+ else {
+ /*
+ * Go through all the 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.
+ */
+ order = mce_start(&no_way_out);
+ }
+
for (i = 0; i < cfg->banks; i++) {
__clear_bit(i, toclear);
if (!test_bit(i, valid_banks))
@@ -1155,8 +1171,18 @@ void do_machine_check(struct pt_regs *regs, long error_code)
* Do most of the synchronization with other CPUs.
* When there's any problem use only local no_way_out state.
*/
- if (mce_end(order) < 0)
- no_way_out = worst >= MCE_PANIC_SEVERITY;
+ if (!lmce) {
+ if (mce_end(order) < 0)
+ 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 (worst >= MCE_PANIC_SEVERITY && mca_cfg.tolerant < 3)
+ mce_panic("Machine check from unknown source",
+ NULL, NULL);
+ }
/*
* At insane "tolerant" levels we take no action. Otherwise
@@ -1637,10 +1663,16 @@ static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 *c)
mce_intel_feature_init(c);
mce_adjust_timer = cmci_intel_adjust_timer;
break;
- case X86_VENDOR_AMD:
+
+ case X86_VENDOR_AMD: {
+ u32 ebx = cpuid_ebx(0x80000007);
+
mce_amd_feature_init(c);
- mce_flags.overflow_recov = cpuid_ebx(0x80000007) & 0x1;
+ mce_flags.overflow_recov = !!(ebx & BIT(0));
+ mce_flags.succor = !!(ebx & BIT(1));
break;
+ }
+
default:
break;
}
@@ -1884,7 +1916,7 @@ out:
static unsigned int mce_chrdev_poll(struct file *file, poll_table *wait)
{
poll_wait(file, &mce_chrdev_wait, wait);
- if (rcu_access_index(mcelog.next))
+ if (READ_ONCE(mcelog.next))
return POLLIN | POLLRDNORM;
if (!mce_apei_read_done && apei_check_mce())
return POLLIN | POLLRDNORM;
@@ -1929,8 +1961,8 @@ void register_mce_write_callback(ssize_t (*fn)(struct file *filp,
}
EXPORT_SYMBOL_GPL(register_mce_write_callback);
-ssize_t mce_chrdev_write(struct file *filp, const char __user *ubuf,
- size_t usize, loff_t *off)
+static ssize_t mce_chrdev_write(struct file *filp, const char __user *ubuf,
+ size_t usize, loff_t *off)
{
if (mce_write)
return mce_write(filp, ubuf, usize, off);
@@ -1976,6 +2008,7 @@ void mce_disable_bank(int bank)
/*
* mce=off Disables machine check
* mce=no_cmci Disables CMCI
+ * mce=no_lmce Disables LMCE
* mce=dont_log_ce Clears corrected events silently, no log created for CEs.
* mce=ignore_ce Disables polling and CMCI, corrected events are not cleared.
* mce=TOLERANCELEVEL[,monarchtimeout] (number, see above)
@@ -1999,6 +2032,8 @@ static int __init mcheck_enable(char *str)
cfg->disabled = true;
else if (!strcmp(str, "no_cmci"))
cfg->cmci_disabled = true;
+ else if (!strcmp(str, "no_lmce"))
+ cfg->lmce_disabled = true;
else if (!strcmp(str, "dont_log_ce"))
cfg->dont_log_ce = true;
else if (!strcmp(str, "ignore_ce"))
@@ -2008,11 +2043,8 @@ static int __init mcheck_enable(char *str)
else if (!strcmp(str, "bios_cmci_threshold"))
cfg->bios_cmci_threshold = true;
else if (isdigit(str[0])) {
- get_option(&str, &(cfg->tolerant));
- if (*str == ',') {
- ++str;
+ if (get_option(&str, &cfg->tolerant) == 2)
get_option(&str, &(cfg->monarch_timeout));
- }
} else {
pr_info("mce argument %s ignored. Please use /sys\n", str);
return 0;
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