diff --git a/arch/arm/include/asm/cacheflush.h b/arch/arm/include/asm/cacheflush.h
index fd43f7f55b70..79ecb4f34ffb 100644
--- a/arch/arm/include/asm/cacheflush.h
+++ b/arch/arm/include/asm/cacheflush.h
@@ -472,7 +472,6 @@ static inline void __sync_cache_range_r(volatile void *p, size_t size)
 	"mcr	p15, 0, r0, c1, c0, 0	@ set SCTLR \n\t" \
 	"isb	\n\t" \
 	"bl	v7_flush_dcache_"__stringify(level)" \n\t" \
-	"clrex	\n\t" \
 	"mrc	p15, 0, r0, c1, c0, 1	@ get ACTLR \n\t" \
 	"bic	r0, r0, #(1 << 6)	@ disable local coherency \n\t" \
 	"mcr	p15, 0, r0, c1, c0, 1	@ set ACTLR \n\t" \
diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h
index 963a2515906d..819777d0e91f 100644
--- a/arch/arm/include/asm/cputype.h
+++ b/arch/arm/include/asm/cputype.h
@@ -74,6 +74,7 @@
 #define ARM_CPU_PART_CORTEX_A12		0x4100c0d0
 #define ARM_CPU_PART_CORTEX_A17		0x4100c0e0
 #define ARM_CPU_PART_CORTEX_A15		0x4100c0f0
+#define ARM_CPU_PART_MASK		0xff00fff0
 
 #define ARM_CPU_XSCALE_ARCH_MASK	0xe000
 #define ARM_CPU_XSCALE_ARCH_V1		0x2000
@@ -179,7 +180,7 @@ static inline unsigned int __attribute_const__ read_cpuid_implementor(void)
  */
 static inline unsigned int __attribute_const__ read_cpuid_part(void)
 {
-	return read_cpuid_id() & 0xff00fff0;
+	return read_cpuid_id() & ARM_CPU_PART_MASK;
 }
 
 static inline unsigned int __attribute_const__ __deprecated read_cpuid_part_number(void)
diff --git a/arch/arm/include/asm/elf.h b/arch/arm/include/asm/elf.h
index f4b46d39b9cf..afb9cafd3786 100644
--- a/arch/arm/include/asm/elf.h
+++ b/arch/arm/include/asm/elf.h
@@ -50,6 +50,7 @@ typedef struct user_fp elf_fpregset_t;
 #define R_ARM_ABS32		2
 #define R_ARM_CALL		28
 #define R_ARM_JUMP24		29
+#define R_ARM_TARGET1		38
 #define R_ARM_V4BX		40
 #define R_ARM_PREL31		42
 #define R_ARM_MOVW_ABS_NC	43
diff --git a/arch/arm/include/asm/smp_plat.h b/arch/arm/include/asm/smp_plat.h
index a252c0bfacf5..0ad7d490ee6f 100644
--- a/arch/arm/include/asm/smp_plat.h
+++ b/arch/arm/include/asm/smp_plat.h
@@ -8,6 +8,7 @@
 #include <linux/cpumask.h>
 #include <linux/err.h>
 
+#include <asm/cpu.h>
 #include <asm/cputype.h>
 
 /*
@@ -25,6 +26,20 @@ static inline bool is_smp(void)
 #endif
 }
 
+/**
+ * smp_cpuid_part() - return part id for a given cpu
+ * @cpu:	logical cpu id.
+ *
+ * Return: part id of logical cpu passed as argument.
+ */
+static inline unsigned int smp_cpuid_part(int cpu)
+{
+	struct cpuinfo_arm *cpu_info = &per_cpu(cpu_data, cpu);
+
+	return is_smp() ? cpu_info->cpuid & ARM_CPU_PART_MASK :
+			  read_cpuid_part();
+}
+
 /* all SMP configurations have the extended CPUID registers */
 #ifndef CONFIG_MMU
 #define tlb_ops_need_broadcast()	0
diff --git a/arch/arm/kernel/entry-header.S b/arch/arm/kernel/entry-header.S
index 8db307d0954b..2fdf8679b46e 100644
--- a/arch/arm/kernel/entry-header.S
+++ b/arch/arm/kernel/entry-header.S
@@ -208,26 +208,21 @@
 #endif
 	.endif
 	msr	spsr_cxsf, \rpsr
-#if defined(CONFIG_CPU_V6)
-	ldr	r0, [sp]
-	strex	r1, r2, [sp]			@ clear the exclusive monitor
-	ldmib	sp, {r1 - pc}^			@ load r1 - pc, cpsr
-#elif defined(CONFIG_CPU_32v6K)
-	clrex					@ clear the exclusive monitor
-	ldmia	sp, {r0 - pc}^			@ load r0 - pc, cpsr
-#else
-	ldmia	sp, {r0 - pc}^			@ load r0 - pc, cpsr
+#if defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_32v6K)
+	@ We must avoid clrex due to Cortex-A15 erratum #830321
+	sub	r0, sp, #4			@ uninhabited address
+	strex	r1, r2, [r0]			@ clear the exclusive monitor
 #endif
+	ldmia	sp, {r0 - pc}^			@ load r0 - pc, cpsr
 	.endm
 
 	.macro	restore_user_regs, fast = 0, offset = 0
 	ldr	r1, [sp, #\offset + S_PSR]	@ get calling cpsr
 	ldr	lr, [sp, #\offset + S_PC]!	@ get pc
 	msr	spsr_cxsf, r1			@ save in spsr_svc
-#if defined(CONFIG_CPU_V6)
+#if defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_32v6K)
+	@ We must avoid clrex due to Cortex-A15 erratum #830321
 	strex	r1, r2, [sp]			@ clear the exclusive monitor
-#elif defined(CONFIG_CPU_32v6K)
-	clrex					@ clear the exclusive monitor
 #endif
 	.if	\fast
 	ldmdb	sp, {r1 - lr}^			@ get calling r1 - lr
@@ -261,7 +256,10 @@
 	.endif
 	ldr	lr, [sp, #S_SP]			@ top of the stack
 	ldrd	r0, r1, [sp, #S_LR]		@ calling lr and pc
-	clrex					@ clear the exclusive monitor
+
+	@ We must avoid clrex due to Cortex-A15 erratum #830321
+	strex	r2, r1, [sp, #S_LR]		@ clear the exclusive monitor
+
 	stmdb	lr!, {r0, r1, \rpsr}		@ calling lr and rfe context
 	ldmia	sp, {r0 - r12}
 	mov	sp, lr
@@ -282,13 +280,16 @@
 	.endm
 #else	/* ifdef CONFIG_CPU_V7M */
 	.macro	restore_user_regs, fast = 0, offset = 0
-	clrex					@ clear the exclusive monitor
 	mov	r2, sp
 	load_user_sp_lr r2, r3, \offset + S_SP	@ calling sp, lr
 	ldr	r1, [sp, #\offset + S_PSR]	@ get calling cpsr
 	ldr	lr, [sp, #\offset + S_PC]	@ get pc
 	add	sp, sp, #\offset + S_SP
 	msr	spsr_cxsf, r1			@ save in spsr_svc
+
+	@ We must avoid clrex due to Cortex-A15 erratum #830321
+	strex	r1, r2, [sp]			@ clear the exclusive monitor
+
 	.if	\fast
 	ldmdb	sp, {r1 - r12}			@ get calling r1 - r12
 	.else
diff --git a/arch/arm/kernel/module.c b/arch/arm/kernel/module.c
index 45e478157278..6a4dffefd357 100644
--- a/arch/arm/kernel/module.c
+++ b/arch/arm/kernel/module.c
@@ -91,6 +91,7 @@ apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
 			break;
 
 		case R_ARM_ABS32:
+		case R_ARM_TARGET1:
 			*(u32 *)loc += sym->st_value;
 			break;
 
diff --git a/arch/arm/mach-exynos/mcpm-exynos.c b/arch/arm/mach-exynos/mcpm-exynos.c
index b2f8b60cf0e9..dc9a764a7c37 100644
--- a/arch/arm/mach-exynos/mcpm-exynos.c
+++ b/arch/arm/mach-exynos/mcpm-exynos.c
@@ -43,7 +43,6 @@
 	"mcr	p15, 0, r0, c1, c0, 0	@ set SCTLR\n\t" \
 	"isb\n\t"\
 	"bl	v7_flush_dcache_"__stringify(level)"\n\t" \
-	"clrex\n\t"\
 	"mrc	p15, 0, r0, c1, c0, 1	@ get ACTLR\n\t" \
 	"bic	r0, r0, #(1 << 6)	@ disable local coherency\n\t" \
 	/* Dummy Load of a device register to avoid Erratum 799270 */ \
diff --git a/arch/arm/mm/abort-ev6.S b/arch/arm/mm/abort-ev6.S
index 3815a8262af0..8c48c5c22a33 100644
--- a/arch/arm/mm/abort-ev6.S
+++ b/arch/arm/mm/abort-ev6.S
@@ -17,12 +17,6 @@
  */
 	.align	5
 ENTRY(v6_early_abort)
-#ifdef CONFIG_CPU_V6
-	sub	r1, sp, #4			@ Get unused stack location
-	strex	r0, r1, [r1]			@ Clear the exclusive monitor
-#elif defined(CONFIG_CPU_32v6K)
-	clrex
-#endif
 	mrc	p15, 0, r1, c5, c0, 0		@ get FSR
 	mrc	p15, 0, r0, c6, c0, 0		@ get FAR
 /*
diff --git a/arch/arm/mm/abort-ev7.S b/arch/arm/mm/abort-ev7.S
index 703375277ba6..4812ad054214 100644
--- a/arch/arm/mm/abort-ev7.S
+++ b/arch/arm/mm/abort-ev7.S
@@ -13,12 +13,6 @@
  */
 	.align	5
 ENTRY(v7_early_abort)
-	/*
-	 * The effect of data aborts on on the exclusive access monitor are
-	 * UNPREDICTABLE. Do a CLREX to clear the state
-	 */
-	clrex
-
 	mrc	p15, 0, r1, c5, c0, 0		@ get FSR
 	mrc	p15, 0, r0, c6, c0, 0		@ get FAR
 
diff --git a/drivers/cpuidle/cpuidle-big_little.c b/drivers/cpuidle/cpuidle-big_little.c
index 344d79fa3407..ef94c3b81f18 100644
--- a/drivers/cpuidle/cpuidle-big_little.c
+++ b/drivers/cpuidle/cpuidle-big_little.c
@@ -138,25 +138,18 @@ static int bl_enter_powerdown(struct cpuidle_device *dev,
 	return idx;
 }
 
-static int __init bl_idle_driver_init(struct cpuidle_driver *drv, int cpu_id)
+static int __init bl_idle_driver_init(struct cpuidle_driver *drv, int part_id)
 {
-	struct cpuinfo_arm *cpu_info;
 	struct cpumask *cpumask;
-	unsigned long cpuid;
 	int cpu;
 
 	cpumask = kzalloc(cpumask_size(), GFP_KERNEL);
 	if (!cpumask)
 		return -ENOMEM;
 
-	for_each_possible_cpu(cpu) {
-		cpu_info = &per_cpu(cpu_data, cpu);
-		cpuid = is_smp() ? cpu_info->cpuid : read_cpuid_id();
-
-		/* read cpu id part number */
-		if ((cpuid & 0xFFF0) == cpu_id)
+	for_each_possible_cpu(cpu)
+		if (smp_cpuid_part(cpu) == part_id)
 			cpumask_set_cpu(cpu, cpumask);
-	}
 
 	drv->cpumask = cpumask;