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Index: linux-pm/kernel/power/hibernate.c
===================================================================
--- linux-pm.orig/kernel/power/hibernate.c
+++ linux-pm/kernel/power/hibernate.c
@@ -409,6 +409,11 @@ int hibernation_snapshot(int platform_mo
goto Close;
}
+int __weak hibernate_resume_nonboot_cpu_disable(void)
+{
+ return disable_nonboot_cpus();
+}
+
/**
* resume_target_kernel - Restore system state from a hibernation image.
* @platform_mode: Whether or not to use the platform driver.
@@ -433,7 +438,7 @@ static int resume_target_kernel(bool pla
if (error)
goto Cleanup;
- error = disable_nonboot_cpus();
+ error = hibernate_resume_nonboot_cpu_disable();
if (error)
goto Enable_cpus;
Index: linux-pm/kernel/power/power.h
===================================================================
--- linux-pm.orig/kernel/power/power.h
+++ linux-pm/kernel/power/power.h
@@ -38,6 +38,8 @@ static inline char *check_image_kernel(s
}
#endif /* CONFIG_ARCH_HIBERNATION_HEADER */
+extern int hibernate_resume_nonboot_cpu_disable(void);
+
/*
* Keep some memory free so that I/O operations can succeed without paging
* [Might this be more than 4 MB?]
Index: linux-pm/arch/x86/power/cpu.c
===================================================================
--- linux-pm.orig/arch/x86/power/cpu.c
+++ linux-pm/arch/x86/power/cpu.c
@@ -266,6 +266,27 @@ void notrace restore_processor_state(voi
EXPORT_SYMBOL(restore_processor_state);
#endif
+#if defined(CONFIG_HIBERNATION) && defined(CONFIG_HOTPLUG_CPU)
+bool force_hlt_play_dead __read_mostly;
+
+int hibernate_resume_nonboot_cpu_disable(void)
+{
+ int ret;
+
+ /*
+ * Ensure that MONITOR/MWAIT will not be used in the "play dead" loop
+ * during hibernate image restoration, because it is likely that the
+ * monitored address will be actually written to at that time and then
+ * the "dead" CPU may start executing instructions from an image
+ * kernel's page (and that may not be the "play dead" loop any more).
+ */
+ force_hlt_play_dead = true;
+ ret = disable_nonboot_cpus();
+ force_hlt_play_dead = false;
+ return ret;
+}
+#endif
+
/*
* When bsp_check() is called in hibernate and suspend, cpu hotplug
* is disabled already. So it's unnessary to handle race condition between
Index: linux-pm/arch/x86/kernel/smpboot.c
===================================================================
--- linux-pm.orig/arch/x86/kernel/smpboot.c
+++ linux-pm/arch/x86/kernel/smpboot.c
@@ -1642,6 +1642,9 @@ void native_play_dead(void)
play_dead_common();
tboot_shutdown(TB_SHUTDOWN_WFS);
+ if (force_hlt_play_dead)
+ hlt_play_dead();
+
mwait_play_dead(); /* Only returns on failure */
if (cpuidle_play_dead())
hlt_play_dead();
Index: linux-pm/arch/x86/include/asm/cpu.h
===================================================================
--- linux-pm.orig/arch/x86/include/asm/cpu.h
+++ linux-pm/arch/x86/include/asm/cpu.h
@@ -26,6 +26,12 @@ struct x86_cpu {
};
#ifdef CONFIG_HOTPLUG_CPU
+#ifdef CONFIG_HIBERNATION
+extern bool force_hlt_play_dead;
+#else
+#define force_hlt_play_dead (false)
+#endif
+
extern int arch_register_cpu(int num);
extern void arch_unregister_cpu(int);
extern void start_cpu0(void);
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