6 files changed, 328 insertions, 84 deletions

diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 71232b941b6c..c2d0baa48d8c 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -504,6 +504,7 @@ int acpi_gsi_to_irq(u32 gsi, unsigned int *irq)
 
         return 0;
 }
+EXPORT_SYMBOL_GPL(acpi_gsi_to_irq);
 
 int acpi_isa_irq_to_gsi(unsigned isa_irq, u32 *gsi)
 {
diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c
index 6e8752c1bd52..d34cf80ec402 100644
--- a/arch/x86/kernel/dumpstack.c
+++ b/arch/x86/kernel/dumpstack.c
@@ -240,6 +240,7 @@ unsigned __kprobes long oops_begin(void)
         bust_spinlocks(1);
         return flags;
 }
+EXPORT_SYMBOL_GPL(oops_begin);
 
 void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr)
 {
diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index 51905d07a4d9..d1d484d4a06a 100644
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -12,10 +12,6 @@
  * For more information about Generic Hardware Error Source, please
  * refer to ACPI Specification version 4.0, section 17.3.2.6
  *
- * Now, only SCI notification type and memory errors are
- * supported. More notification type and hardware error type will be
- * added later.
- *
  * Copyright 2010 Intel Corp.
  *   Author: Huang Ying <ying.huang@intel.com>
  *
@@ -39,15 +35,18 @@
 #include <linux/acpi.h>
 #include <linux/io.h>
 #include <linux/interrupt.h>
+#include <linux/timer.h>
 #include <linux/cper.h>
 #include <linux/kdebug.h>
 #include <linux/platform_device.h>
 #include <linux/mutex.h>
 #include <linux/ratelimit.h>
+#include <linux/vmalloc.h>
 #include <acpi/apei.h>
 #include <acpi/atomicio.h>
 #include <acpi/hed.h>
 #include <asm/mce.h>
+#include <asm/tlbflush.h>
 
 #include "apei-internal.h"
 
@@ -56,42 +55,131 @@
 #define GHES_ESTATUS_MAX_SIZE           65536
 
 /*
- * One struct ghes is created for each generic hardware error
- * source.
- *
+ * One struct ghes is created for each generic hardware error source.
  * It provides the context for APEI hardware error timer/IRQ/SCI/NMI
- * handler. Handler for one generic hardware error source is only
- * triggered after the previous one is done. So handler can uses
- * struct ghes without locking.
+ * handler.
  *
  * estatus: memory buffer for error status block, allocated during
  * HEST parsing.
  */
 #define GHES_TO_CLEAR           0x0001
+#define GHES_EXITING            0x0002
 
 struct ghes {
         struct acpi_hest_generic *generic;
         struct acpi_hest_generic_status *estatus;
-        struct list_head list;
         u64 buffer_paddr;
         unsigned long flags;
+        union {
+                struct list_head list;
+                struct timer_list timer;
+                unsigned int irq;
+        };
 };
 
+static int ghes_panic_timeout   __read_mostly = 30;
+
 /*
- * Error source lists, one list for each notification method. The
- * members in lists are struct ghes.
+ * All error sources notified with SCI shares one notifier function,
+ * so they need to be linked and checked one by one.  This is applied
+ * to NMI too.
  *
- * The list members are only added in HEST parsing and deleted during
- * module_exit, that is, single-threaded. So no lock is needed for
- * that.
- *
- * But the mutual exclusion is needed between members adding/deleting
- * and timer/IRQ/SCI/NMI handler, which may traverse the list. RCU is
- * used for that.
+ * RCU is used for these lists, so ghes_list_mutex is only used for
+ * list changing, not for traversing.
  */
 static LIST_HEAD(ghes_sci);
+static LIST_HEAD(ghes_nmi);
 static DEFINE_MUTEX(ghes_list_mutex);
 
+/*
+ * NMI may be triggered on any CPU, so ghes_nmi_lock is used for
+ * mutual exclusion.
+ */
+static DEFINE_RAW_SPINLOCK(ghes_nmi_lock);
+
+/*
+ * Because the memory area used to transfer hardware error information
+ * from BIOS to Linux can be determined only in NMI, IRQ or timer
+ * handler, but general ioremap can not be used in atomic context, so
+ * a special version of atomic ioremap is implemented for that.
+ */
+
+/*
+ * Two virtual pages are used, one for NMI context, the other for
+ * IRQ/PROCESS context
+ */
+#define GHES_IOREMAP_PAGES              2
+#define GHES_IOREMAP_NMI_PAGE(base)     (base)
+#define GHES_IOREMAP_IRQ_PAGE(base)     ((base) + PAGE_SIZE)
+
+/* virtual memory area for atomic ioremap */
+static struct vm_struct *ghes_ioremap_area;
+/*
+ * These 2 spinlock is used to prevent atomic ioremap virtual memory
+ * area from being mapped simultaneously.
+ */
+static DEFINE_RAW_SPINLOCK(ghes_ioremap_lock_nmi);
+static DEFINE_SPINLOCK(ghes_ioremap_lock_irq);
+
+static int ghes_ioremap_init(void)
+{
+        ghes_ioremap_area = __get_vm_area(PAGE_SIZE * GHES_IOREMAP_PAGES,
+                VM_IOREMAP, VMALLOC_START, VMALLOC_END);
+        if (!ghes_ioremap_area) {
+                pr_err(GHES_PFX "Failed to allocate virtual memory area for atomic ioremap.\n");
+                return -ENOMEM;
+        }
+
+        return 0;
+}
+
+static void ghes_ioremap_exit(void)
+{
+        free_vm_area(ghes_ioremap_area);
+}
+
+static void __iomem *ghes_ioremap_pfn_nmi(u64 pfn)
+{
+        unsigned long vaddr;
+
+        vaddr = (unsigned long)GHES_IOREMAP_NMI_PAGE(ghes_ioremap_area->addr);
+        ioremap_page_range(vaddr, vaddr + PAGE_SIZE,
+                           pfn << PAGE_SHIFT, PAGE_KERNEL);
+
+        return (void __iomem *)vaddr;
+}
+
+static void __iomem *ghes_ioremap_pfn_irq(u64 pfn)
+{
+        unsigned long vaddr;
+
+        vaddr = (unsigned long)GHES_IOREMAP_IRQ_PAGE(ghes_ioremap_area->addr);
+        ioremap_page_range(vaddr, vaddr + PAGE_SIZE,
+                           pfn << PAGE_SHIFT, PAGE_KERNEL);
+
+        return (void __iomem *)vaddr;
+}
+
+static void ghes_iounmap_nmi(void __iomem *vaddr_ptr)
+{
+        unsigned long vaddr = (unsigned long __force)vaddr_ptr;
+        void *base = ghes_ioremap_area->addr;
+
+        BUG_ON(vaddr != (unsigned long)GHES_IOREMAP_NMI_PAGE(base));
+        unmap_kernel_range_noflush(vaddr, PAGE_SIZE);
+        __flush_tlb_one(vaddr);
+}
+
+static void ghes_iounmap_irq(void __iomem *vaddr_ptr)
+{
+        unsigned long vaddr = (unsigned long __force)vaddr_ptr;
+        void *base = ghes_ioremap_area->addr;
+
+        BUG_ON(vaddr != (unsigned long)GHES_IOREMAP_IRQ_PAGE(base));
+        unmap_kernel_range_noflush(vaddr, PAGE_SIZE);
+        __flush_tlb_one(vaddr);
+}
+
 static struct ghes *ghes_new(struct acpi_hest_generic *generic)
 {
         struct ghes *ghes;
@@ -102,7 +190,6 @@ static struct ghes *ghes_new(struct acpi_hest_generic *generic)
         if (!ghes)
                 return ERR_PTR(-ENOMEM);
         ghes->generic = generic;
-        INIT_LIST_HEAD(&ghes->list);
         rc = acpi_pre_map_gar(&generic->error_status_address);
         if (rc)
                 goto err_free;
@@ -159,22 +246,41 @@ static inline int ghes_severity(int severity)
         }
 }
 
-/* SCI handler run in work queue, so ioremap can be used here */
-static int ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len,
-                                 int from_phys)
+static void ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len,
+                                  int from_phys)
 {
-        void *vaddr;
-
-        vaddr = ioremap_cache(paddr, len);
-        if (!vaddr)
-                return -ENOMEM;
-        if (from_phys)
-                memcpy(buffer, vaddr, len);
-        else
-                memcpy(vaddr, buffer, len);
-        iounmap(vaddr);
-
-        return 0;
+        void __iomem *vaddr;
+        unsigned long flags = 0;
+        int in_nmi = in_nmi();
+        u64 offset;
+        u32 trunk;
+
+        while (len > 0) {
+                offset = paddr - (paddr & PAGE_MASK);
+                if (in_nmi) {
+                        raw_spin_lock(&ghes_ioremap_lock_nmi);
+                        vaddr = ghes_ioremap_pfn_nmi(paddr >> PAGE_SHIFT);
+                } else {
+                        spin_lock_irqsave(&ghes_ioremap_lock_irq, flags);
+                        vaddr = ghes_ioremap_pfn_irq(paddr >> PAGE_SHIFT);
+                }
+                trunk = PAGE_SIZE - offset;
+                trunk = min(trunk, len);
+                if (from_phys)
+                        memcpy_fromio(buffer, vaddr + offset, trunk);
+                else
+                        memcpy_toio(vaddr + offset, buffer, trunk);
+                len -= trunk;
+                paddr += trunk;
+                buffer += trunk;
+                if (in_nmi) {
+                        ghes_iounmap_nmi(vaddr);
+                        raw_spin_unlock(&ghes_ioremap_lock_nmi);
+                } else {
+                        ghes_iounmap_irq(vaddr);
+                        spin_unlock_irqrestore(&ghes_ioremap_lock_irq, flags);
+                }
+        }
 }
 
 static int ghes_read_estatus(struct ghes *ghes, int silent)
@@ -195,10 +301,8 @@ static int ghes_read_estatus(struct ghes *ghes, int silent)
         if (!buf_paddr)
                 return -ENOENT;
 
-        rc = ghes_copy_tofrom_phys(ghes->estatus, buf_paddr,
-                                   sizeof(*ghes->estatus), 1);
-        if (rc)
-                return rc;
+        ghes_copy_tofrom_phys(ghes->estatus, buf_paddr,
+                              sizeof(*ghes->estatus), 1);
         if (!ghes->estatus->block_status)
                 return -ENOENT;
 
@@ -213,17 +317,15 @@ static int ghes_read_estatus(struct ghes *ghes, int silent)
                 goto err_read_block;
         if (apei_estatus_check_header(ghes->estatus))
                 goto err_read_block;
-        rc = ghes_copy_tofrom_phys(ghes->estatus + 1,
-                                   buf_paddr + sizeof(*ghes->estatus),
-                                   len - sizeof(*ghes->estatus), 1);
-        if (rc)
-                return rc;
+        ghes_copy_tofrom_phys(ghes->estatus + 1,
+                              buf_paddr + sizeof(*ghes->estatus),
+                              len - sizeof(*ghes->estatus), 1);
         if (apei_estatus_check(ghes->estatus))
                 goto err_read_block;
         rc = 0;
 
 err_read_block:
-        if (rc && !silent)
+        if (rc && !silent && printk_ratelimit())
                 pr_warning(FW_WARN GHES_PFX
                            "Failed to read error status block!\n");
         return rc;
@@ -293,6 +395,42 @@ out:
         return 0;
 }
 
+static void ghes_add_timer(struct ghes *ghes)
+{
+        struct acpi_hest_generic *g = ghes->generic;
+        unsigned long expire;
+
+        if (!g->notify.poll_interval) {
+                pr_warning(FW_WARN GHES_PFX "Poll interval is 0 for generic hardware error source: %d, disabled.\n",
+                           g->header.source_id);
+                return;
+        }
+        expire = jiffies + msecs_to_jiffies(g->notify.poll_interval);
+        ghes->timer.expires = round_jiffies_relative(expire);
+        add_timer(&ghes->timer);
+}
+
+static void ghes_poll_func(unsigned long data)
+{
+        struct ghes *ghes = (void *)data;
+
+        ghes_proc(ghes);
+        if (!(ghes->flags & GHES_EXITING))
+                ghes_add_timer(ghes);
+}
+
+static irqreturn_t ghes_irq_func(int irq, void *data)
+{
+        struct ghes *ghes = data;
+        int rc;
+
+        rc = ghes_proc(ghes);
+        if (rc)
+                return IRQ_NONE;
+
+        return IRQ_HANDLED;
+}
+
 static int ghes_notify_sci(struct notifier_block *this,
                                   unsigned long event, void *data)
 {
@@ -309,10 +447,63 @@ static int ghes_notify_sci(struct notifier_block *this,
         return ret;
 }
 
+static int ghes_notify_nmi(struct notifier_block *this,
+                                  unsigned long cmd, void *data)
+{
+        struct ghes *ghes, *ghes_global = NULL;
+        int sev, sev_global = -1;
+        int ret = NOTIFY_DONE;
+
+        if (cmd != DIE_NMI)
+                return ret;
+
+        raw_spin_lock(&ghes_nmi_lock);
+        list_for_each_entry_rcu(ghes, &ghes_nmi, list) {
+                if (ghes_read_estatus(ghes, 1)) {
+                        ghes_clear_estatus(ghes);
+                        continue;
+                }
+                sev = ghes_severity(ghes->estatus->error_severity);
+                if (sev > sev_global) {
+                        sev_global = sev;
+                        ghes_global = ghes;
+                }
+                ret = NOTIFY_STOP;
+        }
+
+        if (ret == NOTIFY_DONE)
+                goto out;
+
+        if (sev_global >= GHES_SEV_PANIC) {
+                oops_begin();
+                ghes_print_estatus(KERN_EMERG HW_ERR, ghes_global);
+                /* reboot to log the error! */
+                if (panic_timeout == 0)
+                        panic_timeout = ghes_panic_timeout;
+                panic("Fatal hardware error!");
+        }
+
+        list_for_each_entry_rcu(ghes, &ghes_nmi, list) {
+                if (!(ghes->flags & GHES_TO_CLEAR))
+                        continue;
+                /* Do not print estatus because printk is not NMI safe */
+                ghes_do_proc(ghes);
+                ghes_clear_estatus(ghes);
+        }
+
+out:
+        raw_spin_unlock(&ghes_nmi_lock);
+        return ret;
+}
+
 static struct notifier_block ghes_notifier_sci = {
         .notifier_call = ghes_notify_sci,
 };
 
+static struct notifier_block ghes_notifier_nmi = {
+        .notifier_call = ghes_notify_nmi,
+};
+
 static int __devinit ghes_probe(struct platform_device *ghes_dev)
 {
         struct acpi_hest_generic *generic;
@@ -323,18 +514,27 @@ static int __devinit ghes_probe(struct platform_device *ghes_dev)
         if (!generic->enabled)
                 return -ENODEV;
 
-        if (generic->error_block_length <
-            sizeof(struct acpi_hest_generic_status)) {
-                pr_warning(FW_BUG GHES_PFX
-"Invalid error block length: %u for generic hardware error source: %d\n",
-                           generic->error_block_length,
+        switch (generic->notify.type) {
+        case ACPI_HEST_NOTIFY_POLLED:
+        case ACPI_HEST_NOTIFY_EXTERNAL:
+        case ACPI_HEST_NOTIFY_SCI:
+        case ACPI_HEST_NOTIFY_NMI:
+                break;
+        case ACPI_HEST_NOTIFY_LOCAL:
+                pr_warning(GHES_PFX "Generic hardware error source: %d notified via local interrupt is not supported!\n",
                            generic->header.source_id);
                 goto err;
+        default:
+                pr_warning(FW_WARN GHES_PFX "Unknown notification type: %u for generic hardware error source: %d\n",
+                           generic->notify.type, generic->header.source_id);
+                goto err;
         }
-        if (generic->records_to_preallocate == 0) {
-                pr_warning(FW_BUG GHES_PFX
-"Invalid records to preallocate: %u for generic hardware error source: %d\n",
-                           generic->records_to_preallocate,
+
+        rc = -EIO;
+        if (generic->error_block_length <
+            sizeof(struct acpi_hest_generic_status)) {
+                pr_warning(FW_BUG GHES_PFX "Invalid error block length: %u for generic hardware error source: %d\n",
+                           generic->error_block_length,
                            generic->header.source_id);
                 goto err;
         }
@@ -344,38 +544,43 @@ static int __devinit ghes_probe(struct platform_device *ghes_dev)
                 ghes = NULL;
                 goto err;
         }
-        if (generic->notify.type == ACPI_HEST_NOTIFY_SCI) {
+        switch (generic->notify.type) {
+        case ACPI_HEST_NOTIFY_POLLED:
+                ghes->timer.function = ghes_poll_func;
+                ghes->timer.data = (unsigned long)ghes;
+                init_timer_deferrable(&ghes->timer);
+                ghes_add_timer(ghes);
+                break;
+        case ACPI_HEST_NOTIFY_EXTERNAL:
+                /* External interrupt vector is GSI */
+                if (acpi_gsi_to_irq(generic->notify.vector, &ghes->irq)) {
+                        pr_err(GHES_PFX "Failed to map GSI to IRQ for generic hardware error source: %d\n",
+                               generic->header.source_id);
+                        goto err;
+                }
+                if (request_irq(ghes->irq, ghes_irq_func,
+                                0, "GHES IRQ", ghes)) {
+                        pr_err(GHES_PFX "Failed to register IRQ for generic hardware error source: %d\n",
+                               generic->header.source_id);
+                        goto err;
+                }
+                break;
+        case ACPI_HEST_NOTIFY_SCI:
                 mutex_lock(&ghes_list_mutex);
                 if (list_empty(&ghes_sci))
                         register_acpi_hed_notifier(&ghes_notifier_sci);
                 list_add_rcu(&ghes->list, &ghes_sci);
                 mutex_unlock(&ghes_list_mutex);
-        } else {
-                unsigned char *notify = NULL;
-
-                switch (generic->notify.type) {
-                case ACPI_HEST_NOTIFY_POLLED:
-                        notify = "POLL";
-                        break;
-                case ACPI_HEST_NOTIFY_EXTERNAL:
-                case ACPI_HEST_NOTIFY_LOCAL:
-                        notify = "IRQ";
-                        break;
-                case ACPI_HEST_NOTIFY_NMI:
-                        notify = "NMI";
-                        break;
-                }
-                if (notify) {
-                        pr_warning(GHES_PFX
-"Generic hardware error source: %d notified via %s is not supported!\n",
-                                   generic->header.source_id, notify);
-                } else {
-                        pr_warning(FW_WARN GHES_PFX
-"Unknown notification type: %u for generic hardware error source: %d\n",
-                        generic->notify.type, generic->header.source_id);
-                }
-                rc = -ENODEV;
-                goto err;
+                break;
+        case ACPI_HEST_NOTIFY_NMI:
+                mutex_lock(&ghes_list_mutex);
+                if (list_empty(&ghes_nmi))
+                        register_die_notifier(&ghes_notifier_nmi);
+                list_add_rcu(&ghes->list, &ghes_nmi);
+                mutex_unlock(&ghes_list_mutex);
+                break;
+        default:
+                BUG();
         }
         platform_set_drvdata(ghes_dev, ghes);
 
@@ -396,7 +601,14 @@ static int __devexit ghes_remove(struct platform_device *ghes_dev)
         ghes = platform_get_drvdata(ghes_dev);
         generic = ghes->generic;
 
+        ghes->flags |= GHES_EXITING;
         switch (generic->notify.type) {
+        case ACPI_HEST_NOTIFY_POLLED:
+                del_timer_sync(&ghes->timer);
+                break;
+        case ACPI_HEST_NOTIFY_EXTERNAL:
+                free_irq(ghes->irq, ghes);
+                break;
         case ACPI_HEST_NOTIFY_SCI:
                 mutex_lock(&ghes_list_mutex);
                 list_del_rcu(&ghes->list);
@@ -404,12 +616,23 @@ static int __devexit ghes_remove(struct platform_device *ghes_dev)
                         unregister_acpi_hed_notifier(&ghes_notifier_sci);
                 mutex_unlock(&ghes_list_mutex);
                 break;
+        case ACPI_HEST_NOTIFY_NMI:
+                mutex_lock(&ghes_list_mutex);
+                list_del_rcu(&ghes->list);
+                if (list_empty(&ghes_nmi))
+                        unregister_die_notifier(&ghes_notifier_nmi);
+                mutex_unlock(&ghes_list_mutex);
+                /*
+                 * To synchronize with NMI handler, ghes can only be
+                 * freed after NMI handler finishes.
+                 */
+                synchronize_rcu();
+                break;
         default:
                 BUG();
                 break;
         }
 
-        synchronize_rcu();
         ghes_fini(ghes);
         kfree(ghes);
 
@@ -429,6 +652,8 @@ static struct platform_driver ghes_platform_driver = {
 
 static int __init ghes_init(void)
 {
+        int rc;
+
         if (acpi_disabled)
                 return -ENODEV;
 
@@ -437,12 +662,25 @@ static int __init ghes_init(void)
                 return -EINVAL;
         }
 
-        return platform_driver_register(&ghes_platform_driver);
+        rc = ghes_ioremap_init();
+        if (rc)
+                goto err;
+
+        rc = platform_driver_register(&ghes_platform_driver);
+        if (rc)
+                goto err_ioremap_exit;
+
+        return 0;
+err_ioremap_exit:
+        ghes_ioremap_exit();
+err:
+        return rc;
 }
 
 static void __exit ghes_exit(void)
 {
         platform_driver_unregister(&ghes_platform_driver);
+        ghes_ioremap_exit();
 }
 
 module_init(ghes_init);
diff --git a/kernel/panic.c b/kernel/panic.c
index 4c13b1a88ebb..991bb87a1704 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -34,6 +34,7 @@ static int pause_on_oops_flag;
 static DEFINE_SPINLOCK(pause_on_oops_lock);
 
 int panic_timeout;
+EXPORT_SYMBOL_GPL(panic_timeout);
 
 ATOMIC_NOTIFIER_HEAD(panic_notifier_list);
 
diff --git a/lib/ioremap.c b/lib/ioremap.c
index 5730ecd3eb66..da4e2ad74b68 100644
--- a/lib/ioremap.c
+++ b/lib/ioremap.c
@@ -9,6 +9,7 @@
 #include <linux/mm.h>
 #include <linux/sched.h>
 #include <linux/io.h>
+#include <linux/module.h>
 #include <asm/cacheflush.h>
 #include <asm/pgtable.h>
 
@@ -90,3 +91,4 @@ int ioremap_page_range(unsigned long addr,
 
         return err;
 }
+EXPORT_SYMBOL_GPL(ioremap_page_range);
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index eb5cc7d00c5a..816f074fb4e1 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -1175,6 +1175,7 @@ void unmap_kernel_range_noflush(unsigned long addr, unsigned long size)
 {
         vunmap_page_range(addr, addr + size);
 }
+EXPORT_SYMBOL_GPL(unmap_kernel_range_noflush);
 
 /**
  * unmap_kernel_range - unmap kernel VM area and flush cache and TLB