dirty fix to merging

1 files changed, 285 insertions, 0 deletions

diff --git a/arch/x86/kernel/cpu/mcheck/mce-severity.c b/arch/x86/kernel/cpu/mcheck/mce-severity.c
new file mode 100644
index 00000000..1ccd4539
--- /dev/null
+++ b/arch/x86/kernel/cpu/mcheck/mce-severity.c
@@ -0,0 +1,285 @@
+/*
+ * MCE grading rules.
+ * Copyright 2008, 2009 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; version 2
+ * of the License.
+ *
+ * Author: Andi Kleen
+ */
+#include <linux/kernel.h>
+#include <linux/seq_file.h>
+#include <linux/init.h>
+#include <linux/debugfs.h>
+#include <asm/mce.h>
+
+#include "mce-internal.h"
+
+/*
+ * Grade an mce by severity. In general the most severe ones are processed
+ * first. Since there are quite a lot of combinations test the bits in a
+ * table-driven way. The rules are simply processed in order, first
+ * match wins.
+ *
+ * Note this is only used for machine check exceptions, the corrected
+ * errors use much simpler rules. The exceptions still check for the corrected
+ * errors, but only to leave them alone for the CMCI handler (except for
+ * panic situations)
+ */
+
+enum context { IN_KERNEL = 1, IN_USER = 2 };
+enum ser { SER_REQUIRED = 1, NO_SER = 2 };
+
+static struct severity {
+	u64 mask;
+	u64 result;
+	unsigned char sev;
+	unsigned char mcgmask;
+	unsigned char mcgres;
+	unsigned char ser;
+	unsigned char context;
+	unsigned char covered;
+	char *msg;
+} severities[] = {
+#define MCESEV(s, m, c...) { .sev = MCE_ ## s ## _SEVERITY, .msg = m, ## c }
+#define  KERNEL		.context = IN_KERNEL
+#define  USER		.context = IN_USER
+#define  SER		.ser = SER_REQUIRED
+#define  NOSER		.ser = NO_SER
+#define  BITCLR(x)	.mask = x, .result = 0
+#define  BITSET(x)	.mask = x, .result = x
+#define  MCGMASK(x, y)	.mcgmask = x, .mcgres = y
+#define  MASK(x, y)	.mask = x, .result = y
+#define MCI_UC_S (MCI_STATUS_UC|MCI_STATUS_S)
+#define MCI_UC_SAR (MCI_STATUS_UC|MCI_STATUS_S|MCI_STATUS_AR)
+#define	MCI_ADDR (MCI_STATUS_ADDRV|MCI_STATUS_MISCV)
+#define MCACOD 0xffff
+/* Architecturally defined codes from SDM Vol. 3B Chapter 15 */
+#define MCACOD_SCRUB	0x00C0	/* 0xC0-0xCF Memory Scrubbing */
+#define MCACOD_SCRUBMSK	0xfff0
+#define MCACOD_L3WB	0x017A	/* L3 Explicit Writeback */
+#define MCACOD_DATA	0x0134	/* Data Load */
+#define MCACOD_INSTR	0x0150	/* Instruction Fetch */
+
+	MCESEV(
+		NO, "Invalid",
+		BITCLR(MCI_STATUS_VAL)
+		),
+	MCESEV(
+		NO, "Not enabled",
+		BITCLR(MCI_STATUS_EN)
+		),
+	MCESEV(
+		PANIC, "Processor context corrupt",
+		BITSET(MCI_STATUS_PCC)
+		),
+	/* When MCIP is not set something is very confused */
+	MCESEV(
+		PANIC, "MCIP not set in MCA handler",
+		MCGMASK(MCG_STATUS_MCIP, 0)
+		),
+	/* Neither return not error IP -- no chance to recover -> PANIC */
+	MCESEV(
+		PANIC, "Neither restart nor error IP",
+		MCGMASK(MCG_STATUS_RIPV|MCG_STATUS_EIPV, 0)
+		),
+	MCESEV(
+		PANIC, "In kernel and no restart IP",
+		KERNEL, MCGMASK(MCG_STATUS_RIPV, 0)
+		),
+	MCESEV(
+		KEEP, "Corrected error",
+		NOSER, BITCLR(MCI_STATUS_UC)
+		),
+
+	/* ignore OVER for UCNA */
+	MCESEV(
+		KEEP, "Uncorrected no action required",
+		SER, MASK(MCI_UC_SAR, MCI_STATUS_UC)
+		),
+	MCESEV(
+		PANIC, "Illegal combination (UCNA with AR=1)",
+		SER,
+		MASK(MCI_STATUS_OVER|MCI_UC_SAR, MCI_STATUS_UC|MCI_STATUS_AR)
+		),
+	MCESEV(
+		KEEP, "Non signalled machine check",
+		SER, BITCLR(MCI_STATUS_S)
+		),
+
+	MCESEV(
+		PANIC, "Action required with lost events",
+		SER, BITSET(MCI_STATUS_OVER|MCI_UC_SAR)
+		),
+
+	/* known AR MCACODs: */
+#ifdef	CONFIG_MEMORY_FAILURE
+	MCESEV(
+		KEEP, "HT thread notices Action required: data load error",
+		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR|MCI_ADDR|MCACOD, MCI_UC_SAR|MCI_ADDR|MCACOD_DATA),
+		MCGMASK(MCG_STATUS_EIPV, 0)
+		),
+	MCESEV(
+		AR, "Action required: data load error",
+		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR|MCI_ADDR|MCACOD, MCI_UC_SAR|MCI_ADDR|MCACOD_DATA),
+		USER
+		),
+#endif
+	MCESEV(
+		PANIC, "Action required: unknown MCACOD",
+		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR, MCI_UC_SAR)
+		),
+
+	/* known AO MCACODs: */
+	MCESEV(
+		AO, "Action optional: memory scrubbing error",
+		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR|MCACOD_SCRUBMSK, MCI_UC_S|MCACOD_SCRUB)
+		),
+	MCESEV(
+		AO, "Action optional: last level cache writeback error",
+		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR|MCACOD, MCI_UC_S|MCACOD_L3WB)
+		),
+	MCESEV(
+		SOME, "Action optional: unknown MCACOD",
+		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR, MCI_UC_S)
+		),
+	MCESEV(
+		SOME, "Action optional with lost events",
+		SER, MASK(MCI_STATUS_OVER|MCI_UC_SAR, MCI_STATUS_OVER|MCI_UC_S)
+		),
+
+	MCESEV(
+		PANIC, "Overflowed uncorrected",
+		BITSET(MCI_STATUS_OVER|MCI_STATUS_UC)
+		),
+	MCESEV(
+		UC, "Uncorrected",
+		BITSET(MCI_STATUS_UC)
+		),
+	MCESEV(
+		SOME, "No match",
+		BITSET(0)
+		)	/* always matches. keep at end */
+};
+
+/*
+ * If mcgstatus indicated that ip/cs on the stack were
+ * no good, then "m->cs" will be zero and we will have
+ * to assume the worst case (IN_KERNEL) as we actually
+ * have no idea what we were executing when the machine
+ * check hit.
+ * If we do have a good "m->cs" (or a faked one in the
+ * case we were executing in VM86 mode) we can use it to
+ * distinguish an exception taken in user from from one
+ * taken in the kernel.
+ */
+static int error_context(struct mce *m)
+{
+	return ((m->cs & 3) == 3) ? IN_USER : IN_KERNEL;
+}
+
+int mce_severity(struct mce *m, int tolerant, char **msg)
+{
+	enum context ctx = error_context(m);
+	struct severity *s;
+
+	for (s = severities;; s++) {
+		if ((m->status & s->mask) != s->result)
+			continue;
+		if ((m->mcgstatus & s->mcgmask) != s->mcgres)
+			continue;
+		if (s->ser == SER_REQUIRED && !mce_ser)
+			continue;
+		if (s->ser == NO_SER && mce_ser)
+			continue;
+		if (s->context && ctx != s->context)
+			continue;
+		if (msg)
+			*msg = s->msg;
+		s->covered = 1;
+		if (s->sev >= MCE_UC_SEVERITY && ctx == IN_KERNEL) {
+			if (panic_on_oops || tolerant < 1)
+				return MCE_PANIC_SEVERITY;
+		}
+		return s->sev;
+	}
+}
+
+#ifdef CONFIG_DEBUG_FS
+static void *s_start(struct seq_file *f, loff_t *pos)
+{
+	if (*pos >= ARRAY_SIZE(severities))
+		return NULL;
+	return &severities[*pos];
+}
+
+static void *s_next(struct seq_file *f, void *data, loff_t *pos)
+{
+	if (++(*pos) >= ARRAY_SIZE(severities))
+		return NULL;
+	return &severities[*pos];
+}
+
+static void s_stop(struct seq_file *f, void *data)
+{
+}
+
+static int s_show(struct seq_file *f, void *data)
+{
+	struct severity *ser = data;
+	seq_printf(f, "%d\t%s\n", ser->covered, ser->msg);
+	return 0;
+}
+
+static const struct seq_operations severities_seq_ops = {
+	.start	= s_start,
+	.next	= s_next,
+	.stop	= s_stop,
+	.show	= s_show,
+};
+
+static int severities_coverage_open(struct inode *inode, struct file *file)
+{
+	return seq_open(file, &severities_seq_ops);
+}
+
+static ssize_t severities_coverage_write(struct file *file,
+					 const char __user *ubuf,
+					 size_t count, loff_t *ppos)
+{
+	int i;
+	for (i = 0; i < ARRAY_SIZE(severities); i++)
+		severities[i].covered = 0;
+	return count;
+}
+
+static const struct file_operations severities_coverage_fops = {
+	.open		= severities_coverage_open,
+	.release	= seq_release,
+	.read		= seq_read,
+	.write		= severities_coverage_write,
+	.llseek		= seq_lseek,
+};
+
+static int __init severities_debugfs_init(void)
+{
+	struct dentry *dmce, *fsev;
+
+	dmce = mce_get_debugfs_dir();
+	if (!dmce)
+		goto err_out;
+
+	fsev = debugfs_create_file("severities-coverage", 0444, dmce, NULL,
+				   &severities_coverage_fops);
+	if (!fsev)
+		goto err_out;
+
+	return 0;
+
+err_out:
+	return -ENOMEM;
+}
+late_initcall(severities_debugfs_init);
+#endif /* CONFIG_DEBUG_FS */