diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index 4c0cedf4e2c7dda768378223deb024c03a94b7c9..ce4c68a4a8236a4feb70c2b4a7291079d519dc98 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -150,7 +150,9 @@ endif
 
 CFLAGS-$(CONFIG_TUNE_CELL) += $(call cc-option,-mtune=cell)
 
-KBUILD_CPPFLAGS	+= -Iarch/$(ARCH)
+asinstr := $(call as-instr,lis 9$(comma)foo@high,-DHAVE_AS_ATHIGH=1)
+
+KBUILD_CPPFLAGS	+= -Iarch/$(ARCH) $(asinstr)
 KBUILD_AFLAGS	+= -Iarch/$(ARCH)
 KBUILD_CFLAGS	+= -msoft-float -pipe -Iarch/$(ARCH) $(CFLAGS-y)
 CPP		= $(CC) -E $(KBUILD_CFLAGS)
diff --git a/arch/powerpc/include/asm/ppc_asm.h b/arch/powerpc/include/asm/ppc_asm.h
index 6586a40a46ce161f9f654a57d0222db3bc06d611..cded7c1278ef0c419b134cabc74292209391b5c6 100644
--- a/arch/powerpc/include/asm/ppc_asm.h
+++ b/arch/powerpc/include/asm/ppc_asm.h
@@ -318,11 +318,16 @@ GLUE(.,name):
 	addi	reg,reg,(name - 0b)@l;
 
 #ifdef __powerpc64__
+#ifdef HAVE_AS_ATHIGH
+#define __AS_ATHIGH high
+#else
+#define __AS_ATHIGH h
+#endif
 #define LOAD_REG_IMMEDIATE(reg,expr)		\
 	lis     reg,(expr)@highest;		\
 	ori     reg,reg,(expr)@higher;	\
 	rldicr  reg,reg,32,31;		\
-	oris    reg,reg,(expr)@h;		\
+	oris    reg,reg,(expr)@__AS_ATHIGH;	\
 	ori     reg,reg,(expr)@l;
 
 #define LOAD_REG_ADDR(reg,name)			\
diff --git a/arch/powerpc/kernel/machine_kexec_64.c b/arch/powerpc/kernel/machine_kexec_64.c
index 59d229a2a3e08dfcd1f18ca94e56cd00e787c987..879b3aacac3282d8b9de5101c9349d2aea9b8edc 100644
--- a/arch/powerpc/kernel/machine_kexec_64.c
+++ b/arch/powerpc/kernel/machine_kexec_64.c
@@ -237,7 +237,7 @@ static void wake_offline_cpus(void)
 		if (!cpu_online(cpu)) {
 			printk(KERN_INFO "kexec: Waking offline cpu %d.\n",
 			       cpu);
-			cpu_up(cpu);
+			WARN_ON(cpu_up(cpu));
 		}
 	}
 }
diff --git a/kernel/kexec.c b/kernel/kexec.c
index c8380ad203bcd5fe8e78bf9570725730733791f0..28c57069ef681f726f2df133d36e6319d370c25f 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -1683,6 +1683,14 @@ int kernel_kexec(void)
 		kexec_in_progress = true;
 		kernel_restart_prepare(NULL);
 		migrate_to_reboot_cpu();
+
+		/*
+		 * migrate_to_reboot_cpu() disables CPU hotplug assuming that
+		 * no further code needs to use CPU hotplug (which is true in
+		 * the reboot case). However, the kexec path depends on using
+		 * CPU hotplug again; so re-enable it here.
+		 */
+		cpu_hotplug_enable();
 		printk(KERN_EMERG "Starting new kernel\n");
 		machine_shutdown();
 	}