diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug
index 85710e078afb..92fca7463e21 100644
--- a/arch/arm/Kconfig.debug
+++ b/arch/arm/Kconfig.debug
@@ -56,7 +56,7 @@ choice
 
 config UNWINDER_FRAME_POINTER
 	bool "Frame pointer unwinder"
-	depends on !THUMB2_KERNEL && !CC_IS_CLANG
+	depends on !THUMB2_KERNEL
 	select ARCH_WANT_FRAME_POINTERS
 	select FRAME_POINTER
 	help
@@ -1872,7 +1872,7 @@ config DEBUG_UNCOMPRESS
 	  When this option is set, the selected DEBUG_LL output method
 	  will be re-used for normal decompressor output on multiplatform
 	  kernels.
-	  
+
 
 config UNCOMPRESS_INCLUDE
 	string
diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index c3624ca6c0bc..a593d9c4e18a 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -36,7 +36,7 @@ KBUILD_CFLAGS	+= $(call cc-option,-mno-unaligned-access)
 endif
 
 ifeq ($(CONFIG_FRAME_POINTER),y)
-KBUILD_CFLAGS	+=-fno-omit-frame-pointer -mapcs -mno-sched-prolog
+KBUILD_CFLAGS	+=-fno-omit-frame-pointer $(call cc-option,-mapcs,) $(call cc-option,-mno-sched-prolog,)
 endif
 
 ifeq ($(CONFIG_CPU_BIG_ENDIAN),y)
diff --git a/arch/arm/lib/backtrace.S b/arch/arm/lib/backtrace.S
index 1d5210eb4776..fd64eec9f6ae 100644
--- a/arch/arm/lib/backtrace.S
+++ b/arch/arm/lib/backtrace.S
@@ -14,10 +14,7 @@
 @ fp is 0 or stack frame
 
 #define frame	r4
-#define sv_fp	r5
-#define sv_pc	r6
 #define mask	r7
-#define offset	r8
 
 ENTRY(c_backtrace)
 
@@ -25,7 +22,8 @@ ENTRY(c_backtrace)
 		ret	lr
 ENDPROC(c_backtrace)
 #else
-		stmfd	sp!, {r4 - r8, lr}	@ Save an extra register so we have a location...
+		stmfd   sp!, {r4 - r8, fp, lr}	@ Save an extra register
+						@ so we have a location..
 		movs	frame, r0		@ if frame pointer is zero
 		beq	no_frame		@ we have no stack frames
 
@@ -35,11 +33,119 @@ ENDPROC(c_backtrace)
  THUMB(		orreq	mask, #0x03		)
 		movne	mask, #0		@ mask for 32-bit
 
-1:		stmfd	sp!, {pc}		@ calculate offset of PC stored
-		ldr	r0, [sp], #4		@ by stmfd for this CPU
-		adr	r1, 1b
-		sub	offset, r0, r1
 
+#if defined(CONFIG_CC_IS_CLANG)
+/*
+ * Clang does not store pc or sp in function prologues
+ * 		so we don't know exactly where the function
+ * 		starts.
+ * We can treat the current frame's lr as the saved pc and the
+ * 		preceding frame's lr as the lr, but we can't
+ * 		trace the most recent call.
+ * Inserting a false stack frame allows us to reference the
+ * 		function called last in the stacktrace.
+ * If the call instruction was a bl we can look at the callers
+ * 		branch instruction to calculate the saved pc.
+ * We can recover the pc in most cases, but in cases such as
+ * 		calling function pointers we cannot. In this
+ * 		case, default to using the lr. This will be
+ * 		some address in the function, but will not
+ * 		be the function start.
+ * Unfortunately due to the stack frame layout we can't dump
+ *              r0 - r3, but these are less frequently saved.
+ *
+ * Stack frame layout:
+ *             <larger addresses>
+ *             saved lr
+ *    frame => saved fp
+ *             optionally saved caller registers (r4 - r10)
+ *             optionally saved arguments (r0 - r3)
+ *             <top of stack frame>
+ *             <smaller addressses>
+ *
+ * Functions start with the following code sequence:
+ * corrected pc =>  stmfd sp!, {..., fp, lr}
+ *		    add fp, sp, #x
+ *		    stmfd sp!, {r0 - r3} (optional)
+ */
+#define sv_fp	r5
+#define sv_pc	r6
+#define sv_lr   r8
+		add     frame, sp, #20          @ switch to false frame
+for_each_frame:	tst	frame, mask		@ Check for address exceptions
+		bne	no_frame
+
+1001:		ldr	sv_pc, [frame, #4]	@ get saved 'pc'
+1002:		ldr	sv_fp, [frame, #0]	@ get saved fp
+
+		teq     sv_fp, #0               @ make sure next frame exists
+		beq     no_frame
+
+1003:		ldr     sv_lr, [sv_fp, #4]      @ get saved lr from next frame
+
+		//try to find function start
+		ldr     r0, [sv_lr, #-4]        @ get call instruction
+		ldr     r3, .Ldsi+8
+		and     r2, r3, r0              @ is this a bl call
+		teq     r2, r3
+		bne     finished_setup          @ give up if it's not
+		and     r0, #0xffffff           @ get call offset 24-bit int
+		lsl     r0, r0, #8              @ sign extend offset
+		asr     r0, r0, #8
+		ldr     sv_pc, [sv_fp, #4]      @ get lr address
+		add     sv_pc, sv_pc, #-4	@ get call instruction address
+		add     sv_pc, sv_pc, #8        @ take care of prefetch
+		add     sv_pc, sv_pc, r0, lsl #2 @ find function start
+		b       finished_setup
+
+finished_setup:
+
+		bic	sv_pc, sv_pc, mask	@ mask PC/LR for the mode
+
+1004:		mov     r0, sv_pc
+
+		mov     r1, sv_lr
+		mov	r2, frame
+		bic	r1, r1, mask		@ mask PC/LR for the mode
+		bl	dump_backtrace_entry
+
+1005:		ldr	r1, [sv_pc, #0]		@ if stmfd sp!, {..., fp, lr}
+		ldr	r3, .Ldsi		@ instruction exists,
+		teq	r3, r1, lsr #11
+		ldr     r0, [frame]             @ locals are stored in
+						@ the preceding frame
+		subeq	r0, r0, #4
+		bleq	dump_backtrace_stm	@ dump saved registers
+
+		teq	sv_fp, #0		@ zero saved fp means
+		beq	no_frame		@ no further frames
+
+		cmp	sv_fp, frame		@ next frame must be
+		mov	frame, sv_fp		@ above the current frame
+		bhi	for_each_frame
+
+1006:		adr	r0, .Lbad
+		mov	r1, frame
+		bl	printk
+no_frame:	ldmfd	sp!, {r4 - r8, fp, pc}
+ENDPROC(c_backtrace)
+		.pushsection __ex_table,"a"
+		.align	3
+		.long	1001b, 1006b
+		.long	1002b, 1006b
+		.long	1003b, 1006b
+		.long	1004b, 1006b
+		.popsection
+
+.Lbad:		.asciz	"Backtrace aborted due to bad frame pointer <%p>\n"
+		.align
+.Ldsi:		.word	0xe92d4800 >> 11	@ stmfd sp!, {... fp, lr}
+		.word	0xe92d0000 >> 11	@ stmfd sp!, {}
+		.word   0x0b000000              @ bl if these bits are set
+
+ENDPROC(c_backtrace)
+
+#else
 /*
  * Stack frame layout:
  *             optionally saved caller registers (r4 - r10)
@@ -55,6 +161,15 @@ ENDPROC(c_backtrace)
  *                  stmfd sp!, {r0 - r3} (optional)
  * corrected pc =>  stmfd sp!, {..., fp, ip, lr, pc}
  */
+#define sv_fp	r5
+#define sv_pc	r6
+#define offset	r8
+
+1:		stmfd	sp!, {pc}		@ calculate offset of PC stored
+		ldr	r0, [sp], #4		@ by stmfd for this CPU
+		adr	r1, 1b
+		sub	offset, r0, r1
+
 for_each_frame:	tst	frame, mask		@ Check for address exceptions
 		bne	no_frame
 
@@ -98,7 +213,7 @@ for_each_frame:	tst	frame, mask		@ Check for address exceptions
 1006:		adr	r0, .Lbad
 		mov	r1, frame
 		bl	printk
-no_frame:	ldmfd	sp!, {r4 - r8, pc}
+no_frame:	ldmfd	sp!, {r4 - r8, fp, pc}
 ENDPROC(c_backtrace)
 		
 		.pushsection __ex_table,"a"
@@ -115,3 +230,4 @@ ENDPROC(c_backtrace)
 		.word	0xe92d0000 >> 11	@ stmfd sp!, {}
 
 #endif
+#endif
