1 files changed, 137 insertions, 0 deletions
diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c
new file mode 100644
index 00000000000..507de806659
--- /dev/null
+++ b/arch/x86/kernel/crash.c
@@ -0,0 +1,137 @@
+/*
+ * Architecture specific (i386/x86_64) functions for kexec based crash dumps.
+ *
+ * Created by: Hariprasad Nellitheertha (hari@in.ibm.com)
+ *
+ * Copyright (C) IBM Corporation, 2004. All rights reserved.
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/smp.h>
+#include <linux/reboot.h>
+#include <linux/kexec.h>
+#include <linux/delay.h>
+#include <linux/elf.h>
+#include <linux/elfcore.h>
+#include <linux/module.h>
+
+#include <asm/processor.h>
+#include <asm/hardirq.h>
+#include <asm/nmi.h>
+#include <asm/hw_irq.h>
+#include <asm/apic.h>
+#include <asm/hpet.h>
+#include <linux/kdebug.h>
+#include <asm/cpu.h>
+#include <asm/reboot.h>
+#include <asm/virtext.h>
+
+int in_crash_kexec;
+
+/*
+ * This is used to VMCLEAR all VMCSs loaded on the
+ * processor. And when loading kvm_intel module, the
+ * callback function pointer will be assigned.
+ *
+ * protected by rcu.
+ */
+crash_vmclear_fn __rcu *crash_vmclear_loaded_vmcss = NULL;
+EXPORT_SYMBOL_GPL(crash_vmclear_loaded_vmcss);
+
+static inline void cpu_crash_vmclear_loaded_vmcss(void)
+{
+	crash_vmclear_fn *do_vmclear_operation = NULL;
+
+	rcu_read_lock();
+	do_vmclear_operation = rcu_dereference(crash_vmclear_loaded_vmcss);
+	if (do_vmclear_operation)
+		do_vmclear_operation();
+	rcu_read_unlock();
+}
+
+#if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC)
+
+static void kdump_nmi_callback(int cpu, struct pt_regs *regs)
+{
+#ifdef CONFIG_X86_32
+	struct pt_regs fixed_regs;
+
+	if (!user_mode_vm(regs)) {
+		crash_fixup_ss_esp(&fixed_regs, regs);
+		regs = &fixed_regs;
+	}
+#endif
+	crash_save_cpu(regs, cpu);
+
+	/*
+	 * VMCLEAR VMCSs loaded on all cpus if needed.
+	 */
+	cpu_crash_vmclear_loaded_vmcss();
+
+	/* Disable VMX or SVM if needed.
+	 *
+	 * We need to disable virtualization on all CPUs.
+	 * Having VMX or SVM enabled on any CPU may break rebooting
+	 * after the kdump kernel has finished its task.
+	 */
+	cpu_emergency_vmxoff();
+	cpu_emergency_svm_disable();
+
+	disable_local_APIC();
+}
+
+static void kdump_nmi_shootdown_cpus(void)
+{
+	in_crash_kexec = 1;
+	nmi_shootdown_cpus(kdump_nmi_callback);
+
+	disable_local_APIC();
+}
+
+#else
+static void kdump_nmi_shootdown_cpus(void)
+{
+	/* There are no cpus to shootdown */
+}
+#endif
+
+void native_machine_crash_shutdown(struct pt_regs *regs)
+{
+	/* This function is only called after the system
+	 * has panicked or is otherwise in a critical state.
+	 * The minimum amount of code to allow a kexec'd kernel
+	 * to run successfully needs to happen here.
+	 *
+	 * In practice this means shooting down the other cpus in
+	 * an SMP system.
+	 */
+	/* The kernel is broken so disable interrupts */
+	local_irq_disable();
+
+	kdump_nmi_shootdown_cpus();
+
+	/*
+	 * VMCLEAR VMCSs loaded on this cpu if needed.
+	 */
+	cpu_crash_vmclear_loaded_vmcss();
+
+	/* Booting kdump kernel with VMX or SVM enabled won't work,
+	 * because (among other limitations) we can't disable paging
+	 * with the virt flags.
+	 */
+	cpu_emergency_vmxoff();
+	cpu_emergency_svm_disable();
+
+#ifdef CONFIG_X86_IO_APIC
+	/* Prevent crash_kexec() from deadlocking on ioapic_lock. */
+	ioapic_zap_locks();
+	disable_IO_APIC();
+#endif
+	lapic_shutdown();
+#ifdef CONFIG_HPET_TIMER
+	hpet_disable();
+#endif
+	crash_save_cpu(regs, safe_smp_processor_id());
+}