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-rw-r--r--arch/i386/kernel/alternative.c15
-rw-r--r--arch/i386/kernel/cpu/mcheck/mce.c14
-rw-r--r--arch/i386/kernel/traps.c17
-rw-r--r--arch/x86_64/kernel/mce.c14
-rw-r--r--arch/x86_64/kernel/nmi.c17
-rw-r--r--include/asm-i386/mce.h4
-rw-r--r--include/asm-i386/nmi.h2
-rw-r--r--include/asm-x86_64/mce.h3
-rw-r--r--include/asm-x86_64/nmi.h2
9 files changed, 86 insertions, 2 deletions
diff --git a/arch/i386/kernel/alternative.c b/arch/i386/kernel/alternative.c
index 206ea2ca63c..c3750c2c411 100644
--- a/arch/i386/kernel/alternative.c
+++ b/arch/i386/kernel/alternative.c
@@ -8,6 +8,8 @@
#include <asm/alternative.h>
#include <asm/sections.h>
#include <asm/pgtable.h>
+#include <asm/mce.h>
+#include <asm/nmi.h>
#ifdef CONFIG_HOTPLUG_CPU
static int smp_alt_once;
@@ -373,6 +375,14 @@ void __init alternative_instructions(void)
{
unsigned long flags;
+ /* The patching is not fully atomic, so try to avoid local interruptions
+ that might execute the to be patched code.
+ Other CPUs are not running. */
+ stop_nmi();
+#ifdef CONFIG_MCE
+ stop_mce();
+#endif
+
local_irq_save(flags);
apply_alternatives(__alt_instructions, __alt_instructions_end);
@@ -405,6 +415,11 @@ void __init alternative_instructions(void)
#endif
apply_paravirt(__parainstructions, __parainstructions_end);
local_irq_restore(flags);
+
+ restart_nmi();
+#ifdef CONFIG_MCE
+ restart_mce();
+#endif
}
/*
diff --git a/arch/i386/kernel/cpu/mcheck/mce.c b/arch/i386/kernel/cpu/mcheck/mce.c
index 56cd485b127..34c781eddee 100644
--- a/arch/i386/kernel/cpu/mcheck/mce.c
+++ b/arch/i386/kernel/cpu/mcheck/mce.c
@@ -60,6 +60,20 @@ void mcheck_init(struct cpuinfo_x86 *c)
}
}
+static unsigned long old_cr4 __initdata;
+
+void __init stop_mce(void)
+{
+ old_cr4 = read_cr4();
+ clear_in_cr4(X86_CR4_MCE);
+}
+
+void __init restart_mce(void)
+{
+ if (old_cr4 & X86_CR4_MCE)
+ set_in_cr4(X86_CR4_MCE);
+}
+
static int __init mcheck_disable(char *str)
{
mce_disabled = 1;
diff --git a/arch/i386/kernel/traps.c b/arch/i386/kernel/traps.c
index 438949da3b6..cfffe3dd9e8 100644
--- a/arch/i386/kernel/traps.c
+++ b/arch/i386/kernel/traps.c
@@ -775,6 +775,8 @@ static __kprobes void default_do_nmi(struct pt_regs * regs)
reassert_nmi();
}
+static int ignore_nmis;
+
fastcall __kprobes void do_nmi(struct pt_regs * regs, long error_code)
{
int cpu;
@@ -785,11 +787,24 @@ fastcall __kprobes void do_nmi(struct pt_regs * regs, long error_code)
++nmi_count(cpu);
- default_do_nmi(regs);
+ if (!ignore_nmis)
+ default_do_nmi(regs);
nmi_exit();
}
+void stop_nmi(void)
+{
+ acpi_nmi_disable();
+ ignore_nmis++;
+}
+
+void restart_nmi(void)
+{
+ ignore_nmis--;
+ acpi_nmi_enable();
+}
+
#ifdef CONFIG_KPROBES
fastcall void __kprobes do_int3(struct pt_regs *regs, long error_code)
{
diff --git a/arch/x86_64/kernel/mce.c b/arch/x86_64/kernel/mce.c
index 4d8450ee363..a66d607f5b9 100644
--- a/arch/x86_64/kernel/mce.c
+++ b/arch/x86_64/kernel/mce.c
@@ -667,6 +667,20 @@ static struct miscdevice mce_log_device = {
&mce_chrdev_ops,
};
+static unsigned long old_cr4 __initdata;
+
+void __init stop_mce(void)
+{
+ old_cr4 = read_cr4();
+ clear_in_cr4(X86_CR4_MCE);
+}
+
+void __init restart_mce(void)
+{
+ if (old_cr4 & X86_CR4_MCE)
+ set_in_cr4(X86_CR4_MCE);
+}
+
/*
* Old style boot options parsing. Only for compatibility.
*/
diff --git a/arch/x86_64/kernel/nmi.c b/arch/x86_64/kernel/nmi.c
index edbbc59b752..cb8ee9d02f8 100644
--- a/arch/x86_64/kernel/nmi.c
+++ b/arch/x86_64/kernel/nmi.c
@@ -384,11 +384,14 @@ int __kprobes nmi_watchdog_tick(struct pt_regs * regs, unsigned reason)
return rc;
}
+static unsigned ignore_nmis;
+
asmlinkage __kprobes void do_nmi(struct pt_regs * regs, long error_code)
{
nmi_enter();
add_pda(__nmi_count,1);
- default_do_nmi(regs);
+ if (!ignore_nmis)
+ default_do_nmi(regs);
nmi_exit();
}
@@ -401,6 +404,18 @@ int do_nmi_callback(struct pt_regs * regs, int cpu)
return 0;
}
+void stop_nmi(void)
+{
+ acpi_nmi_disable();
+ ignore_nmis++;
+}
+
+void restart_nmi(void)
+{
+ ignore_nmis--;
+ acpi_nmi_enable();
+}
+
#ifdef CONFIG_SYSCTL
static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu)
diff --git a/include/asm-i386/mce.h b/include/asm-i386/mce.h
index b0a02ee34ff..d56d89742e8 100644
--- a/include/asm-i386/mce.h
+++ b/include/asm-i386/mce.h
@@ -5,3 +5,7 @@ extern void mcheck_init(struct cpuinfo_x86 *c);
#endif
extern int mce_disabled;
+
+extern void stop_mce(void);
+extern void restart_mce(void);
+
diff --git a/include/asm-i386/nmi.h b/include/asm-i386/nmi.h
index fb1e133efd9..ff30c98f87b 100644
--- a/include/asm-i386/nmi.h
+++ b/include/asm-i386/nmi.h
@@ -57,5 +57,7 @@ unsigned lapic_adjust_nmi_hz(unsigned hz);
int lapic_watchdog_ok(void);
void disable_lapic_nmi_watchdog(void);
void enable_lapic_nmi_watchdog(void);
+void stop_nmi(void);
+void restart_nmi(void);
#endif /* ASM_NMI_H */
diff --git a/include/asm-x86_64/mce.h b/include/asm-x86_64/mce.h
index 556be5563e3..7bc030a1996 100644
--- a/include/asm-x86_64/mce.h
+++ b/include/asm-x86_64/mce.h
@@ -107,6 +107,9 @@ extern void do_machine_check(struct pt_regs *, long);
extern int mce_notify_user(void);
+extern void stop_mce(void);
+extern void restart_mce(void);
+
#endif
#endif
diff --git a/include/asm-x86_64/nmi.h b/include/asm-x86_64/nmi.h
index d0a7f53b149..5fb3c0de5cc 100644
--- a/include/asm-x86_64/nmi.h
+++ b/include/asm-x86_64/nmi.h
@@ -88,5 +88,7 @@ unsigned lapic_adjust_nmi_hz(unsigned hz);
int lapic_watchdog_ok(void);
void disable_lapic_nmi_watchdog(void);
void enable_lapic_nmi_watchdog(void);
+void stop_nmi(void);
+void restart_nmi(void);
#endif /* ASM_NMI_H */