projects/linux·commit 3959df1d

Merge branch 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

3959df1d · Linus Torvalds <[email protected]> · 2015-08-31 20:20:30 -07:00

Pull RAS updates from Ingo Molnar:
 "MCE handling updates, but also some generic drivers/edac/ changes to
  better organize the Kconfig space"

* 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/ras: Move AMD MCE injector to arch/x86/ras/
  x86/mce: Add a wrapper around mce_log() for injection
  x86/mce: Rename rcu_dereference_check_mce() to mce_log_get_idx_check()
  RAS: Add a menuconfig option with descriptive text
  x86/mce: Reenable CMCI banks when swiching back to interrupt mode
  x86/mce: Clear Local MCE opt-in before kexec
  x86/mce: Remove unused function declarations
  x86/mce: Kill drain_mcelog_buffer()
  x86/mce: Avoid potential deadlock due to printk() in MCE context
  x86/mce: Remove the MCE ring for Action Optional errors
  x86/mce: Don't use percpu workqueues
  x86/mce: Provide a lockless memory pool to save error records
  x86/mce: Reuse one of the u16 padding fields in 'struct mce'
Commit
3959df1dfb9538498ec3372a2d390bc7fbdbfac2
Parents
41d859a8 · 6c36dfe9

Merge commit. Changes below are compared with the first parent: 41d859a8.

Changes

18 files changed · +329 −164

Only the first 600 diff lines are shown. Download the complete patch.

arch/x86/Kconfig

View file
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index b3a1a5d..06dbb5d 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -955,6 +955,7 @@ config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
config X86_MCE
bool "Machine Check / overheating reporting"
+ select GENERIC_ALLOCATOR
default y
---help---
Machine Check support allows the processor to notify the

arch/x86/Makefile

View file
diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index 118e6de..0f38418 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -212,6 +212,8 @@ 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

arch/x86/include/asm/mce.h

View file
diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h
index 982dfc3..2dbc0bf 100644
--- a/arch/x86/include/asm/mce.h
+++ b/arch/x86/include/asm/mce.h
@@ -151,10 +151,12 @@ extern int mce_p5_enabled;
#ifdef CONFIG_X86_MCE
int mcheck_init(void);
void mcheck_cpu_init(struct cpuinfo_x86 *c);
+void mcheck_cpu_clear(struct cpuinfo_x86 *c);
void mcheck_vendor_init_severity(void);
#else
static inline int mcheck_init(void) { return 0; }
static inline void mcheck_cpu_init(struct cpuinfo_x86 *c) {}
+static inline void mcheck_cpu_clear(struct cpuinfo_x86 *c) {}
static inline void mcheck_vendor_init_severity(void) {}
#endif
@@ -181,20 +183,18 @@ DECLARE_PER_CPU(struct device *, mce_device);
#ifdef CONFIG_X86_MCE_INTEL
void mce_intel_feature_init(struct cpuinfo_x86 *c);
+void mce_intel_feature_clear(struct cpuinfo_x86 *c);
void cmci_clear(void);
void cmci_reenable(void);
void cmci_rediscover(void);
void cmci_recheck(void);
-void lmce_clear(void);
-void lmce_enable(void);
#else
static inline void mce_intel_feature_init(struct cpuinfo_x86 *c) { }
+static inline void mce_intel_feature_clear(struct cpuinfo_x86 *c) { }
static inline void cmci_clear(void) {}
static inline void cmci_reenable(void) {}
static inline void cmci_rediscover(void) {}
static inline void cmci_recheck(void) {}
-static inline void lmce_clear(void) {}
-static inline void lmce_enable(void) {}
#endif
#ifdef CONFIG_X86_MCE_AMD

arch/x86/include/uapi/asm/mce.h

View file
diff --git a/arch/x86/include/uapi/asm/mce.h b/arch/x86/include/uapi/asm/mce.h
index a0eab85..76880ed 100644
--- a/arch/x86/include/uapi/asm/mce.h
+++ b/arch/x86/include/uapi/asm/mce.h
@@ -15,7 +15,8 @@ struct mce {
__u64 time; /* wall time_t when error was detected */
__u8 cpuvendor; /* cpu vendor as encoded in system.h */
__u8 inject_flags; /* software inject flags */
- __u16 pad;
+ __u8 severity;
+ __u8 usable_addr;
__u32 cpuid; /* CPUID 1 EAX */
__u8 cs; /* code segment */
__u8 bank; /* machine check bank */

arch/x86/kernel/cpu/mcheck/Makefile

View file
diff --git a/arch/x86/kernel/cpu/mcheck/Makefile b/arch/x86/kernel/cpu/mcheck/Makefile
index bb34b03..a3311c8 100644
--- a/arch/x86/kernel/cpu/mcheck/Makefile
+++ b/arch/x86/kernel/cpu/mcheck/Makefile
@@ -1,4 +1,4 @@
-obj-y = mce.o mce-severity.o
+obj-y = mce.o mce-severity.o mce-genpool.o
obj-$(CONFIG_X86_ANCIENT_MCE) += winchip.o p5.o
obj-$(CONFIG_X86_MCE_INTEL) += mce_intel.o

arch/x86/kernel/cpu/mcheck/mce-apei.c

View file
diff --git a/arch/x86/kernel/cpu/mcheck/mce-apei.c b/arch/x86/kernel/cpu/mcheck/mce-apei.c
index a1aef95..34c89a3 100644
--- a/arch/x86/kernel/cpu/mcheck/mce-apei.c
+++ b/arch/x86/kernel/cpu/mcheck/mce-apei.c
@@ -57,7 +57,6 @@ void apei_mce_report_mem_error(int severity, struct cper_sec_mem_err *mem_err)
m.addr = mem_err->physical_addr;
mce_log(&m);
- mce_notify_irq();
}
EXPORT_SYMBOL_GPL(apei_mce_report_mem_error);

arch/x86/kernel/cpu/mcheck/mce-genpool.c

View file
diff --git a/arch/x86/kernel/cpu/mcheck/mce-genpool.c b/arch/x86/kernel/cpu/mcheck/mce-genpool.c
new file mode 100644
index 0000000..0a85010
--- /dev/null
+++ b/arch/x86/kernel/cpu/mcheck/mce-genpool.c
@@ -0,0 +1,99 @@
+/*
+ * MCE event pool management in MCE context
+ *
+ * Copyright (C) 2015 Intel Corp.
+ * Author: Chen, Gong <[email protected]>
+ *
+ * This file is licensed under GPLv2.
+ */
+#include <linux/smp.h>
+#include <linux/mm.h>
+#include <linux/genalloc.h>
+#include <linux/llist.h>
+#include "mce-internal.h"
+
+/*
+ * printk() is not safe in MCE context. This is a lock-less memory allocator
+ * used to save error information organized in a lock-less list.
+ *
+ * This memory pool is only to be used to save MCE records in MCE context.
+ * MCE events are rare, so a fixed size memory pool should be enough. Use
+ * 2 pages to save MCE events for now (~80 MCE records at most).
+ */
+#define MCE_POOLSZ (2 * PAGE_SIZE)
+
+static struct gen_pool *mce_evt_pool;
+static LLIST_HEAD(mce_event_llist);
+static char gen_pool_buf[MCE_POOLSZ];
+
+void mce_gen_pool_process(void)
+{
+ struct llist_node *head;
+ struct mce_evt_llist *node;
+ struct mce *mce;
+
+ head = llist_del_all(&mce_event_llist);
+ if (!head)
+ return;
+
+ head = llist_reverse_order(head);
+ llist_for_each_entry(node, head, llnode) {
+ mce = &node->mce;
+ atomic_notifier_call_chain(&x86_mce_decoder_chain, 0, mce);
+ gen_pool_free(mce_evt_pool, (unsigned long)node, sizeof(*node));
+ }
+}
+
+bool mce_gen_pool_empty(void)
+{
+ return llist_empty(&mce_event_llist);
+}
+
+int mce_gen_pool_add(struct mce *mce)
+{
+ struct mce_evt_llist *node;
+
+ if (!mce_evt_pool)
+ return -EINVAL;
+
+ node = (void *)gen_pool_alloc(mce_evt_pool, sizeof(*node));
+ if (!node) {
+ pr_warn_ratelimited("MCE records pool full!\n");
+ return -ENOMEM;
+ }
+
+ memcpy(&node->mce, mce, sizeof(*mce));
+ llist_add(&node->llnode, &mce_event_llist);
+
+ return 0;
+}
+
+static int mce_gen_pool_create(void)
+{
+ struct gen_pool *tmpp;
+ int ret = -ENOMEM;
+
+ tmpp = gen_pool_create(ilog2(sizeof(struct mce_evt_llist)), -1);
+ if (!tmpp)
+ goto out;
+
+ ret = gen_pool_add(tmpp, (unsigned long)gen_pool_buf, MCE_POOLSZ, -1);
+ if (ret) {
+ gen_pool_destroy(tmpp);
+ goto out;
+ }
+
+ mce_evt_pool = tmpp;
+
+out:
+ return ret;
+}
+
+int mce_gen_pool_init(void)
+{
+ /* Just init mce_gen_pool once. */
+ if (mce_evt_pool)
+ return 0;
+
+ return mce_gen_pool_create();
+}

arch/x86/kernel/cpu/mcheck/mce-internal.h

View file
diff --git a/arch/x86/kernel/cpu/mcheck/mce-internal.h b/arch/x86/kernel/cpu/mcheck/mce-internal.h
index fe32074..547720e 100644
--- a/arch/x86/kernel/cpu/mcheck/mce-internal.h
+++ b/arch/x86/kernel/cpu/mcheck/mce-internal.h
@@ -13,6 +13,8 @@ enum severity_level {
MCE_PANIC_SEVERITY,
};
+extern struct atomic_notifier_head x86_mce_decoder_chain;
+
#define ATTR_LEN 16
#define INITIAL_CHECK_INTERVAL 5 * 60 /* 5 minutes */
@@ -24,6 +26,16 @@ struct mce_bank {
char attrname[ATTR_LEN]; /* attribute name */
};
+struct mce_evt_llist {
+ struct llist_node llnode;
+ struct mce mce;
+};
+
+void mce_gen_pool_process(void);
+bool mce_gen_pool_empty(void);
+int mce_gen_pool_add(struct mce *mce);
+int mce_gen_pool_init(void);
+
extern int (*mce_severity)(struct mce *a, int tolerant, char **msg, bool is_excp);
struct dentry *mce_get_debugfs_dir(void);
@@ -67,3 +79,5 @@ static inline int apei_clear_mce(u64 record_id)
return -EINVAL;
}
#endif
+
+void mce_inject_log(struct mce *m);

arch/x86/kernel/cpu/mcheck/mce.c

View file
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index 3d6b526..0f8f21c 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -52,11 +52,11 @@
static DEFINE_MUTEX(mce_chrdev_read_mutex);
-#define rcu_dereference_check_mce(p) \
+#define mce_log_get_idx_check(p) \
({ \
RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held() && \
!lockdep_is_held(&mce_chrdev_read_mutex), \
- "suspicious rcu_dereference_check_mce() usage"); \
+ "suspicious mce_log_get_idx_check() usage"); \
smp_load_acquire(&(p)); \
})
@@ -110,15 +110,17 @@ DEFINE_PER_CPU(mce_banks_t, mce_poll_banks) = {
*/
mce_banks_t mce_banks_ce_disabled;
-static DEFINE_PER_CPU(struct work_struct, mce_work);
+static struct work_struct mce_work;
+static struct irq_work mce_irq_work;
static void (*quirk_no_way_out)(int bank, struct mce *m, struct pt_regs *regs);
+static int mce_usable_address(struct mce *m);
/*
* CPU/chipset specific EDAC code can register a notifier call here to print
* MCE errors in a human-readable form.
*/
-static ATOMIC_NOTIFIER_HEAD(x86_mce_decoder_chain);
+ATOMIC_NOTIFIER_HEAD(x86_mce_decoder_chain);
/* Do initial initialization of a struct mce */
void mce_setup(struct mce *m)
@@ -157,12 +159,13 @@ void mce_log(struct mce *mce)
/* Emit the trace record: */
trace_mce_record(mce);
- atomic_notifier_call_chain(&x86_mce_decoder_chain, 0, mce);
+ if (!mce_gen_pool_add(mce))
+ irq_work_queue(&mce_irq_work);
mce->finished = 0;
wmb();
for (;;) {
- entry = rcu_dereference_check_mce(mcelog.next);
+ entry = mce_log_get_idx_check(mcelog.next);
for (;;) {
/*
@@ -196,48 +199,23 @@ void mce_log(struct mce *mce)
set_bit(0, &mce_need_notify);
}
-static void drain_mcelog_buffer(void)
+void mce_inject_log(struct mce *m)
{
- unsigned int next, i, prev = 0;
-
- next = ACCESS_ONCE(mcelog.next);
-
- do {
- struct mce *m;
-
- /* drain what was logged during boot */
- for (i = prev; i < next; i++) {
- unsigned long start = jiffies;
- unsigned retries = 1;
-
- m = &mcelog.entry[i];
-
- while (!m->finished) {
- if (time_after_eq(jiffies, start + 2*retries))
- retries++;
-
- cpu_relax();
-
- if (!m->finished && retries >= 4) {
- pr_err("skipping error being logged currently!\n");
- break;
- }
- }
- smp_rmb();
- atomic_notifier_call_chain(&x86_mce_decoder_chain, 0, m);
- }
-
- memset(mcelog.entry + prev, 0, (next - prev) * sizeof(*m));
- prev = next;
- next = cmpxchg(&mcelog.next, prev, 0);
- } while (next != prev);
+ mutex_lock(&mce_chrdev_read_mutex);
+ mce_log(m);
+ mutex_unlock(&mce_chrdev_read_mutex);
}
+EXPORT_SYMBOL_GPL(mce_inject_log);
+static struct notifier_block mce_srao_nb;
void mce_register_decode_chain(struct notifier_block *nb)
{
+ /* Ensure SRAO notifier has the highest priority in the decode chain. */
+ if (nb != &mce_srao_nb && nb->priority == INT_MAX)
+ nb->priority -= 1;
+
atomic_notifier_chain_register(&x86_mce_decoder_chain, nb);
- drain_mcelog_buffer();
}
EXPORT_SYMBOL_GPL(mce_register_decode_chain);
@@ -461,61 +439,6 @@ static inline void mce_gather_info(struct mce *m, struct pt_regs *regs)
}
}
-/*
- * Simple lockless ring to communicate PFNs from the exception handler with the
- * process context work function. This is vastly simplified because there's
- * only a single reader and a single writer.
- */
-#define MCE_RING_SIZE 16 /* we use one entry less */
-
-struct mce_ring {
- unsigned short start;
- unsigned short end;
- unsigned long ring[MCE_RING_SIZE];
-};
-static DEFINE_PER_CPU(struct mce_ring, mce_ring);
-
-/* Runs with CPU affinity in workqueue */
-static int mce_ring_empty(void)
-{
- struct mce_ring *r = this_cpu_ptr(&mce_ring);
-
- return r->start == r->end;
-}
-
-static int mce_ring_get(unsigned long *pfn)
-{
- struct mce_ring *r;
- int ret = 0;
-
- *pfn = 0;
- get_cpu();
- r = this_cpu_ptr(&mce_ring);
- if (r->start == r->end)
- goto out;
- *pfn = r->ring[r->start];
- r->start = (r->start + 1) % MCE_RING_SIZE;
- ret = 1;
-out:
- put_cpu();
- return ret;
-}
-
-/* Always runs in MCE context with preempt off */
-static int mce_ring_add(unsigned long pfn)
-{
- struct mce_ring *r = this_cpu_ptr(&mce_ring);
- unsigned next;
-
- next = (r->end + 1) % MCE_RING_SIZE;
- if (next == r->start)
- return -1;
- r->ring[r->end] = pfn;
- wmb();
- r->end = next;
- return 0;
-}
-
int mce_available(struct cpuinfo_x86 *c)
{
if (mca_cfg.disabled)
@@ -525,12 +448,10 @@ int mce_available(struct cpuinfo_x86 *c)
static void mce_schedule_work(void)
{
- if (!mce_ring_empty())
- schedule_work(this_cpu_ptr(&mce_work));
+ if (!mce_gen_pool_empty() && keventd_up())
+ schedule_work(&mce_work);
}
-static DEFINE_PER_CPU(struct irq_work, mce_irq_work);
-
static void mce_irq_work_cb(struct irq_work *entry)
{
mce_notify_irq();
@@ -551,8 +472,29 @@ static void mce_report_event(struct pt_regs *regs)
return;
}
- irq_work_queue(this_cpu_ptr(&mce_irq_work));
+ irq_work_queue(&mce_irq_work);
+}
+
+static int srao_decode_notifier(struct notifier_block *nb, unsigned long val,
+ void *data)
+{
+ struct mce *mce = (struct mce *)data;
+ unsigned long pfn;
+
+ if (!mce)
+ return NOTIFY_DONE;
+
+ if (mce->usable_addr && (mce->severity == MCE_AO_SEVERITY)) {
+ pfn = mce->addr >> PAGE_SHIFT;
+ memory_failure(pfn, MCE_VECTOR, 0);
+ }
+
+ return NOTIFY_OK;
}
+static struct notifier_block mce_srao_nb = {
+ .notifier_call = srao_decode_notifier,
+ .priority = INT_MAX,
+};
/*
* Read ADDR and MISC registers.
@@ -672,8 +614,11 @@ bool machine_check_poll(enum mcp_flags flags, mce_banks_t *b)
*/
if (severity == MCE_DEFERRED_SEVERITY && memory_error(&m)) {
if (m.status & MCI_STATUS_ADDRV) {
- mce_ring_add(m.addr >> PAGE_SHIFT);
- mce_schedule_work();
+ m.severity = severity;
+ m.usable_addr = mce_usable_address(&m);
+
+ if (!mce_gen_pool_add(&m))
+ mce_schedule_work();
}
}
@@ -1143,15 +1088,9 @@ void do_machine_check(struct pt_regs *regs, long error_code)
mce_read_aux(&m, i);
- /*
- * Action optional error. Queue address for later processing.
- * When the ring overflows we just ignore the AO error.
- * RED-PEN add some logging mechanism when
- * usable_address or mce_add_ring fails.
- * RED-PEN don't ignore overflow for mca_cfg.tolerant == 0
- */
- if (severity == MCE_AO_SEVERITY && mce_usable_address(&m))
- mce_ring_add(m.addr >> PAGE_SHIFT);
+ /* assuming valid severity level != 0 */
+ m.severity = severity;
+ m.usable_addr = mce_usable_address(&m);
mce_log(&m);
@@ -1247,14 +1186,11 @@ int memory_failure(unsigned long pfn, int vector, int flags)
/*
* Action optional processing happens here (picking up
* from the list of faulting pages that do_machine_check()
- * placed into the "ring").
+ * placed into the genpool).
*/
static void mce_process_work(struct work_struct *dummy)
{
- unsigned long pfn;
-
- while (mce_ring_get(&pfn))
- memory_failure(pfn, MCE_VECTOR, 0);
+ mce_gen_pool_process();
}
#ifdef CONFIG_X86_MCE_INTEL
@@ -1678,6 +1614,17 @@ static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 *c)
}
}
+static void __mcheck_cpu_clear_vendor(struct cpuinfo_x86 *c)
+{
+ switch (c->x86_vendor) {
+ case X86_VENDOR_INTEL:
+ mce_intel_feature_clear(c);
+ break;
+ default:
+ break;
+ }
+}
+
static void mce_start_timer(unsigned int cpu, struct timer_list *t)
{
unsigned long iv = check_interval * HZ;
@@ -1731,13 +1678,36 @@ void mcheck_cpu_init(struct cpuinfo_x86 *c)
return;
}
+ if (mce_gen_pool_init()) {
+ mca_cfg.disabled = true;
+ pr_emerg("Couldn't allocate MCE records pool!\n");
+ return;
+ }
+
machine_check_vector = do_machine_check;
__mcheck_cpu_init_generic();
__mcheck_cpu_init_vendor(c);
__mcheck_cpu_init_timer();
- INIT_WORK(this_cpu_ptr(&mce_work), mce_process_work);
- init_irq_work(this_cpu_ptr(&mce_irq_work), &mce_irq_work_cb);
+}
+
+/*
+ * Called for each booted CPU to clear some machine checks opt-ins
+ */
+void mcheck_cpu_clear(struct cpuinfo_x86 *c)
+{
+ if (mca_cfg.disabled)
+ return;
+
+ if (!mce_available(c))
+ return;
+
+ /*
+ * Possibly to clear general settings generic to x86
+ * __mcheck_cpu_clear_generic(c);
+ */
+ __mcheck_cpu_clear_vendor(c);
+
}
/*
@@ -1850,7 +1820,7 @@ static ssize_t mce_chrdev_read(struct file *filp, char __user *ubuf,
goto out;
}
- next = rcu_dereference_check_mce(mcelog.next);
+ next = mce_log_get_idx_check(mcelog.next);
/* Only supports full reads right now */
err = -EINVAL;
@@ -2056,8 +2026,12 @@ __setup("mce", mcheck_enable);
int __init mcheck_init(void)
{
mcheck_intel_therm_init();
+ mce_register_decode_chain(&mce_srao_nb);
mcheck_vendor_init_severity();
+ INIT_WORK(&mce_work, mce_process_work);
+ init_irq_work(&mce_irq_work, mce_irq_work_cb);
+
return 0;
}
@@ -2591,5 +2565,20 @@ static int __init mcheck_debugfs_init(void)
return 0;
}
-late_initcall(mcheck_debugfs_init);
+#else
+static int __init mcheck_debugfs_init(void) { return -EINVAL; }
#endif

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arch/x86/kernel/cpu/mcheck/mce_intel.c

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arch/x86/kernel/process.c

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arch/x86/kernel/smp.c

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arch/x86/ras/Kconfig

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arch/x86/ras/Makefile

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arch/x86/ras/mce_amd_inj.c

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drivers/edac/Kconfig

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drivers/edac/Makefile

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drivers/ras/Kconfig

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