summaryrefslogtreecommitdiff
path: root/arch/x86/kernel/cpu/mce
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2019-05-06 19:54:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-05-06 19:54:57 -0700
commitffa6f55eb6188ee73339cab710fabf30d13110a7 (patch)
tree75d28b242e5807b88bf3074d23421592b81d6cc6 /arch/x86/kernel/cpu/mce
parent275b103a26e218b3d739e5ab15be6b40303a1428 (diff)
parent71a84402b93e5fbd8f817f40059c137e10171788 (diff)
Merge branch 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RAS updates from Borislav Petkov: - Support for varying MCA bank numbers per CPU: this is in preparation for future CPU enablement (Yazen Ghannam) - MCA banks read race fix (Tony Luck) - Facility to filter MCEs which should not be logged (Yazen Ghannam) - The usual round of cleanups and fixes * 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/MCE/AMD: Don't report L1 BTB MCA errors on some family 17h models x86/MCE: Add an MCE-record filtering function RAS/CEC: Increment cec_entered under the mutex lock x86/mce: Fix debugfs_simple_attr.cocci warnings x86/mce: Remove mce_report_event() x86/mce: Handle varying MCA bank counts x86/mce: Fix machine_check_poll() tests for error types MAINTAINERS: Fix file pattern for X86 MCE INFRASTRUCTURE x86/MCE: Group AMD function prototypes in <asm/mce.h>
Diffstat (limited to 'arch/x86/kernel/cpu/mce')
-rw-r--r--arch/x86/kernel/cpu/mce/amd.c52
-rw-r--r--arch/x86/kernel/cpu/mce/core.c102
-rw-r--r--arch/x86/kernel/cpu/mce/genpool.c3
-rw-r--r--arch/x86/kernel/cpu/mce/inject.c14
-rw-r--r--arch/x86/kernel/cpu/mce/internal.h9
5 files changed, 116 insertions, 64 deletions
diff --git a/arch/x86/kernel/cpu/mce/amd.c b/arch/x86/kernel/cpu/mce/amd.c
index e64de5149e50..d904aafe6409 100644
--- a/arch/x86/kernel/cpu/mce/amd.c
+++ b/arch/x86/kernel/cpu/mce/amd.c
@@ -563,33 +563,59 @@ out:
return offset;
}
+bool amd_filter_mce(struct mce *m)
+{
+ enum smca_bank_types bank_type = smca_get_bank_type(m->bank);
+ struct cpuinfo_x86 *c = &boot_cpu_data;
+ u8 xec = (m->status >> 16) & 0x3F;
+
+ /* See Family 17h Models 10h-2Fh Erratum #1114. */
+ if (c->x86 == 0x17 &&
+ c->x86_model >= 0x10 && c->x86_model <= 0x2F &&
+ bank_type == SMCA_IF && xec == 10)
+ return true;
+
+ return false;
+}
+
/*
- * Turn off MC4_MISC thresholding banks on all family 0x15 models since
- * they're not supported there.
+ * Turn off thresholding banks for the following conditions:
+ * - MC4_MISC thresholding is not supported on Family 0x15.
+ * - Prevent possible spurious interrupts from the IF bank on Family 0x17
+ * Models 0x10-0x2F due to Erratum #1114.
*/
-void disable_err_thresholding(struct cpuinfo_x86 *c)
+void disable_err_thresholding(struct cpuinfo_x86 *c, unsigned int bank)
{
- int i;
+ int i, num_msrs;
u64 hwcr;
bool need_toggle;
- u32 msrs[] = {
- 0x00000413, /* MC4_MISC0 */
- 0xc0000408, /* MC4_MISC1 */
- };
+ u32 msrs[NR_BLOCKS];
+
+ if (c->x86 == 0x15 && bank == 4) {
+ msrs[0] = 0x00000413; /* MC4_MISC0 */
+ msrs[1] = 0xc0000408; /* MC4_MISC1 */
+ num_msrs = 2;
+ } else if (c->x86 == 0x17 &&
+ (c->x86_model >= 0x10 && c->x86_model <= 0x2F)) {
- if (c->x86 != 0x15)
+ if (smca_get_bank_type(bank) != SMCA_IF)
+ return;
+
+ msrs[0] = MSR_AMD64_SMCA_MCx_MISC(bank);
+ num_msrs = 1;
+ } else {
return;
+ }
rdmsrl(MSR_K7_HWCR, hwcr);
/* McStatusWrEn has to be set */
need_toggle = !(hwcr & BIT(18));
-
if (need_toggle)
wrmsrl(MSR_K7_HWCR, hwcr | BIT(18));
/* Clear CntP bit safely */
- for (i = 0; i < ARRAY_SIZE(msrs); i++)
+ for (i = 0; i < num_msrs; i++)
msr_clear_bit(msrs[i], 62);
/* restore old settings */
@@ -604,12 +630,12 @@ void mce_amd_feature_init(struct cpuinfo_x86 *c)
unsigned int bank, block, cpu = smp_processor_id();
int offset = -1;
- disable_err_thresholding(c);
-
for (bank = 0; bank < mca_cfg.banks; ++bank) {
if (mce_flags.smca)
smca_configure(bank, cpu);
+ disable_err_thresholding(c, bank);
+
for (block = 0; block < NR_BLOCKS; ++block) {
address = get_block_address(address, low, high, bank, block);
if (!address)
diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index b7fb541a4873..5112a50e6486 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -460,23 +460,6 @@ static void mce_irq_work_cb(struct irq_work *entry)
mce_schedule_work();
}
-static void mce_report_event(struct pt_regs *regs)
-{
- if (regs->flags & (X86_VM_MASK|X86_EFLAGS_IF)) {
- mce_notify_irq();
- /*
- * Triggering the work queue here is just an insurance
- * policy in case the syscall exit notify handler
- * doesn't run soon enough or ends up running on the
- * wrong CPU (can happen when audit sleeps)
- */
- mce_schedule_work();
- return;
- }
-
- irq_work_queue(&mce_irq_work);
-}
-
/*
* Check if the address reported by the CPU is in a format we can parse.
* It would be possible to add code for most other cases, but all would
@@ -712,19 +695,49 @@ bool machine_check_poll(enum mcp_flags flags, mce_banks_t *b)
barrier();
m.status = mce_rdmsrl(msr_ops.status(i));
+
+ /* If this entry is not valid, ignore it */
if (!(m.status & MCI_STATUS_VAL))
continue;
/*
- * Uncorrected or signalled events are handled by the exception
- * handler when it is enabled, so don't process those here.
- *
- * TBD do the same check for MCI_STATUS_EN here?
+ * If we are logging everything (at CPU online) or this
+ * is a corrected error, then we must log it.
*/
- if (!(flags & MCP_UC) &&
- (m.status & (mca_cfg.ser ? MCI_STATUS_S : MCI_STATUS_UC)))
- continue;
+ if ((flags & MCP_UC) || !(m.status & MCI_STATUS_UC))
+ goto log_it;
+
+ /*
+ * Newer Intel systems that support software error
+ * recovery need to make additional checks. Other
+ * CPUs should skip over uncorrected errors, but log
+ * everything else.
+ */
+ if (!mca_cfg.ser) {
+ if (m.status & MCI_STATUS_UC)
+ continue;
+ goto log_it;
+ }
+ /* Log "not enabled" (speculative) errors */
+ if (!(m.status & MCI_STATUS_EN))
+ goto log_it;
+
+ /*
+ * Log UCNA (SDM: 15.6.3 "UCR Error Classification")
+ * UC == 1 && PCC == 0 && S == 0
+ */
+ if (!(m.status & MCI_STATUS_PCC) && !(m.status & MCI_STATUS_S))
+ goto log_it;
+
+ /*
+ * Skip anything else. Presumption is that our read of this
+ * bank is racing with a machine check. Leave the log alone
+ * for do_machine_check() to deal with it.
+ */
+ continue;
+
+log_it:
error_seen = true;
mce_read_aux(&m, i);
@@ -1301,7 +1314,8 @@ void do_machine_check(struct pt_regs *regs, long error_code)
mce_panic("Fatal machine check on current CPU", &m, msg);
if (worst > 0)
- mce_report_event(regs);
+ irq_work_queue(&mce_irq_work);
+
mce_wrmsrl(MSR_IA32_MCG_STATUS, 0);
sync_core();
@@ -1451,13 +1465,12 @@ EXPORT_SYMBOL_GPL(mce_notify_irq);
static int __mcheck_cpu_mce_banks_init(void)
{
int i;
- u8 num_banks = mca_cfg.banks;
- mce_banks = kcalloc(num_banks, sizeof(struct mce_bank), GFP_KERNEL);
+ mce_banks = kcalloc(MAX_NR_BANKS, sizeof(struct mce_bank), GFP_KERNEL);
if (!mce_banks)
return -ENOMEM;
- for (i = 0; i < num_banks; i++) {
+ for (i = 0; i < MAX_NR_BANKS; i++) {
struct mce_bank *b = &mce_banks[i];
b->ctl = -1ULL;
@@ -1471,28 +1484,19 @@ static int __mcheck_cpu_mce_banks_init(void)
*/
static int __mcheck_cpu_cap_init(void)
{
- unsigned b;
u64 cap;
+ u8 b;
rdmsrl(MSR_IA32_MCG_CAP, cap);
b = cap & MCG_BANKCNT_MASK;
- if (!mca_cfg.banks)
- pr_info("CPU supports %d MCE banks\n", b);
-
- if (b > MAX_NR_BANKS) {
- pr_warn("Using only %u machine check banks out of %u\n",
- MAX_NR_BANKS, b);
+ if (WARN_ON_ONCE(b > MAX_NR_BANKS))
b = MAX_NR_BANKS;
- }
- /* Don't support asymmetric configurations today */
- WARN_ON(mca_cfg.banks != 0 && b != mca_cfg.banks);
- mca_cfg.banks = b;
+ mca_cfg.banks = max(mca_cfg.banks, b);
if (!mce_banks) {
int err = __mcheck_cpu_mce_banks_init();
-
if (err)
return err;
}
@@ -1771,6 +1775,14 @@ static void __mcheck_cpu_init_timer(void)
mce_start_timer(t);
}
+bool filter_mce(struct mce *m)
+{
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
+ return amd_filter_mce(m);
+
+ return false;
+}
+
/* Handle unconfigured int18 (should never happen) */
static void unexpected_machine_check(struct pt_regs *regs, long error_code)
{
@@ -2425,8 +2437,8 @@ static int fake_panic_set(void *data, u64 val)
return 0;
}
-DEFINE_SIMPLE_ATTRIBUTE(fake_panic_fops, fake_panic_get,
- fake_panic_set, "%llu\n");
+DEFINE_DEBUGFS_ATTRIBUTE(fake_panic_fops, fake_panic_get, fake_panic_set,
+ "%llu\n");
static int __init mcheck_debugfs_init(void)
{
@@ -2435,8 +2447,8 @@ static int __init mcheck_debugfs_init(void)
dmce = mce_get_debugfs_dir();
if (!dmce)
return -ENOMEM;
- ffake_panic = debugfs_create_file("fake_panic", 0444, dmce, NULL,
- &fake_panic_fops);
+ ffake_panic = debugfs_create_file_unsafe("fake_panic", 0444, dmce,
+ NULL, &fake_panic_fops);
if (!ffake_panic)
return -ENOMEM;
@@ -2451,6 +2463,8 @@ EXPORT_SYMBOL_GPL(mcsafe_key);
static int __init mcheck_late_init(void)
{
+ pr_info("Using %d MCE banks\n", mca_cfg.banks);
+
if (mca_cfg.recovery)
static_branch_inc(&mcsafe_key);
diff --git a/arch/x86/kernel/cpu/mce/genpool.c b/arch/x86/kernel/cpu/mce/genpool.c
index 3395549c51d3..64d1d5a00f39 100644
--- a/arch/x86/kernel/cpu/mce/genpool.c
+++ b/arch/x86/kernel/cpu/mce/genpool.c
@@ -99,6 +99,9 @@ int mce_gen_pool_add(struct mce *mce)
{
struct mce_evt_llist *node;
+ if (filter_mce(mce))
+ return -EINVAL;
+
if (!mce_evt_pool)
return -EINVAL;
diff --git a/arch/x86/kernel/cpu/mce/inject.c b/arch/x86/kernel/cpu/mce/inject.c
index 3da9a8823e47..a6026170af92 100644
--- a/arch/x86/kernel/cpu/mce/inject.c
+++ b/arch/x86/kernel/cpu/mce/inject.c
@@ -46,8 +46,6 @@
static struct mce i_mce;
static struct dentry *dfs_inj;
-static u8 n_banks;
-
#define MAX_FLAG_OPT_SIZE 4
#define NBCFG 0x44
@@ -570,9 +568,15 @@ err:
static int inj_bank_set(void *data, u64 val)
{
struct mce *m = (struct mce *)data;
+ u8 n_banks;
+ u64 cap;
+
+ /* Get bank count on target CPU so we can handle non-uniform values. */
+ rdmsrl_on_cpu(m->extcpu, MSR_IA32_MCG_CAP, &cap);
+ n_banks = cap & MCG_BANKCNT_MASK;
if (val >= n_banks) {
- pr_err("Non-existent MCE bank: %llu\n", val);
+ pr_err("MCA bank %llu non-existent on CPU%d\n", val, m->extcpu);
return -EINVAL;
}
@@ -665,10 +669,6 @@ static struct dfs_node {
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)
diff --git a/arch/x86/kernel/cpu/mce/internal.h b/arch/x86/kernel/cpu/mce/internal.h
index af5eab1e65e2..a34b55baa7aa 100644
--- a/arch/x86/kernel/cpu/mce/internal.h
+++ b/arch/x86/kernel/cpu/mce/internal.h
@@ -173,4 +173,13 @@ struct mca_msr_regs {
extern struct mca_msr_regs msr_ops;
+/* Decide whether to add MCE record to MCE event pool or filter it out. */
+extern bool filter_mce(struct mce *m);
+
+#ifdef CONFIG_X86_MCE_AMD
+extern bool amd_filter_mce(struct mce *m);
+#else
+static inline bool amd_filter_mce(struct mce *m) { return false; };
+#endif
+
#endif /* __X86_MCE_INTERNAL_H__ */