Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus

Pull MIPS fixes from Ralf Baechle:
 "A set of MIPS fixes for 4.9:

   - lots of fixes for printk continuations
   - six fixes for FP related code.
   - fix max_low_pfn with disabled highmem
   - fix KASLR handling of NULL FDT and KASLR for generic kernels
   - fix build of compressed image
   - provide default mips_cpc_default_phys_base to ignore CPC
   - fix reboot on Malta"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: Fix max_low_pfn with disabled highmem
  MIPS: Correct MIPS I FP sigcontext layout
  MIPS: Fix ISA I/II FP signal context offsets
  MIPS: Remove FIR from ISA I FP signal context
  MIPS: Fix ISA I FP sigcontext access violation handling
  MIPS: Fix FCSR Cause bit handling for correct SIGFPE issue
  MIPS: ptrace: Also initialize the FP context on individual FCSR writes
  MIPS: dump_tlb: Fix printk continuations
  MIPS: Fix __show_regs() output
  MIPS: traps: Fix output of show_code
  MIPS: traps: Fix output of show_stacktrace
  MIPS: traps: Fix output of show_backtrace
  MIPS: Fix build of compressed image
  MIPS: generic: Fix KASLR for generic kernel.
  MIPS: KASLR: Fix handling of NULL FDT
  MIPS: Malta: Fixup reboot
  MIPS: CPC: Provide default mips_cpc_default_phys_base to ignore CPC

15 files changed, 287 insertions, 235 deletions

diff --git a/arch/mips/Makefile b/arch/mips/Makefile
index fbf40d3..1a6bac7 100644
--- a/arch/mips/Makefile
+++ b/arch/mips/Makefile
@@ -263,7 +263,7 @@ KBUILD_CPPFLAGS += -DDATAOFFSET=$(if $(dataoffset-y),$(dataoffset-y),0)
 
 bootvars-y	= VMLINUX_LOAD_ADDRESS=$(load-y) \
 		  VMLINUX_ENTRY_ADDRESS=$(entry-y) \
-		  PLATFORM=$(platform-y)
+		  PLATFORM="$(platform-y)"
 ifdef CONFIG_32BIT
 bootvars-y	+= ADDR_BITS=32
 endif
diff --git a/arch/mips/boot/dts/mti/malta.dts b/arch/mips/boot/dts/mti/malta.dts
index f604a27..ffe3a15 100644
--- a/arch/mips/boot/dts/mti/malta.dts
+++ b/arch/mips/boot/dts/mti/malta.dts
@@ -84,12 +84,13 @@
 	fpga_regs: system-controller@1f000000 {
 		compatible = "mti,malta-fpga", "syscon", "simple-mfd";
 		reg = <0x1f000000 0x1000>;
+		native-endian;
 
 		reboot {
 			compatible = "syscon-reboot";
 			regmap = <&fpga_regs>;
 			offset = <0x500>;
-			mask = <0x4d>;
+			mask = <0x42>;
 		};
 	};
 
diff --git a/arch/mips/generic/init.c b/arch/mips/generic/init.c
index 0ea73e8..d493ccb 100644
--- a/arch/mips/generic/init.c
+++ b/arch/mips/generic/init.c
@@ -30,9 +30,19 @@ static __initdata const void *mach_match_data;
 
 void __init prom_init(void)
 {
+	plat_get_fdt();
+	BUG_ON(!fdt);
+}
+
+void __init *plat_get_fdt(void)
+{
 	const struct mips_machine *check_mach;
 	const struct of_device_id *match;
 
+	if (fdt)
+		/* Already set up */
+		return (void *)fdt;
+
 	if ((fw_arg0 == -2) && !fdt_check_header((void *)fw_arg1)) {
 		/*
 		 * We booted using the UHI boot protocol, so we have been
@@ -75,12 +85,6 @@ void __init prom_init(void)
 		/* Retrieve the machine's FDT */
 		fdt = mach->fdt;
 	}
-
-	BUG_ON(!fdt);
-}
-
-void __init *plat_get_fdt(void)
-{
 	return (void *)fdt;
 }
 
diff --git a/arch/mips/include/asm/fpu_emulator.h b/arch/mips/include/asm/fpu_emulator.h
index 355dc25..c05369e 100644
--- a/arch/mips/include/asm/fpu_emulator.h
+++ b/arch/mips/include/asm/fpu_emulator.h
@@ -63,6 +63,8 @@ do {									\
 extern int fpu_emulator_cop1Handler(struct pt_regs *xcp,
 				    struct mips_fpu_struct *ctx, int has_fpu,
 				    void *__user *fault_addr);
+void force_fcr31_sig(unsigned long fcr31, void __user *fault_addr,
+		     struct task_struct *tsk);
 int process_fpemu_return(int sig, void __user *fault_addr,
 			 unsigned long fcr31);
 int isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn,
@@ -81,4 +83,15 @@ static inline void fpu_emulator_init_fpu(void)
 		set_fpr64(&t->thread.fpu.fpr[i], 0, SIGNALLING_NAN);
 }
 
+/*
+ * Mask the FCSR Cause bits according to the Enable bits, observing
+ * that Unimplemented is always enabled.
+ */
+static inline unsigned long mask_fcr31_x(unsigned long fcr31)
+{
+	return fcr31 & (FPU_CSR_UNI_X |
+			((fcr31 & FPU_CSR_ALL_E) <<
+			 (ffs(FPU_CSR_ALL_X) - ffs(FPU_CSR_ALL_E))));
+}
+
 #endif /* _ASM_FPU_EMULATOR_H */
diff --git a/arch/mips/include/asm/switch_to.h b/arch/mips/include/asm/switch_to.h
index ebb5c0f..c0ae279 100644
--- a/arch/mips/include/asm/switch_to.h
+++ b/arch/mips/include/asm/switch_to.h
@@ -76,6 +76,22 @@ do {	if (cpu_has_rw_llb) {						\
 } while (0)
 
 /*
+ * Check FCSR for any unmasked exceptions pending set with `ptrace',
+ * clear them and send a signal.
+ */
+#define __sanitize_fcr31(next)						\
+do {									\
+	unsigned long fcr31 = mask_fcr31_x(next->thread.fpu.fcr31);	\
+	void __user *pc;						\
+									\
+	if (unlikely(fcr31)) {						\
+		pc = (void __user *)task_pt_regs(next)->cp0_epc;	\
+		next->thread.fpu.fcr31 &= ~fcr31;			\
+		force_fcr31_sig(fcr31, pc, next);			\
+	}								\
+} while (0)
+
+/*
  * For newly created kernel threads switch_to() will return to
  * ret_from_kernel_thread, newly created user threads to ret_from_fork.
  * That is, everything following resume() will be skipped for new threads.
@@ -85,6 +101,8 @@ do {	if (cpu_has_rw_llb) {						\
 do {									\
 	__mips_mt_fpaff_switch_to(prev);				\
 	lose_fpu_inatomic(1, prev);					\
+	if (tsk_used_math(next))					\
+		__sanitize_fcr31(next);					\
 	if (cpu_has_dsp) {						\
 		__save_dsp(prev);					\
 		__restore_dsp(next);					\
diff --git a/arch/mips/kernel/mips-cpc.c b/arch/mips/kernel/mips-cpc.c
index 2a45867..a4964c3 100644
--- a/arch/mips/kernel/mips-cpc.c
+++ b/arch/mips/kernel/mips-cpc.c
@@ -21,6 +21,11 @@ static DEFINE_PER_CPU_ALIGNED(spinlock_t, cpc_core_lock);
 
 static DEFINE_PER_CPU_ALIGNED(unsigned long, cpc_core_lock_flags);
 
+phys_addr_t __weak mips_cpc_default_phys_base(void)
+{
+	return 0;
+}
+
 /**
  * mips_cpc_phys_base - retrieve the physical base address of the CPC
  *
@@ -43,8 +48,12 @@ static phys_addr_t mips_cpc_phys_base(void)
 	if (cpc_base & CM_GCR_CPC_BASE_CPCEN_MSK)
 		return cpc_base & CM_GCR_CPC_BASE_CPCBASE_MSK;
 
-	/* Otherwise, give it the default address & enable it */
+	/* Otherwise, use the default address */
 	cpc_base = mips_cpc_default_phys_base();
+	if (!cpc_base)
+		return cpc_base;
+
+	/* Enable the CPC, mapped at the default address */
 	write_gcr_cpc_base(cpc_base | CM_GCR_CPC_BASE_CPCEN_MSK);
 	return cpc_base;
 }
diff --git a/arch/mips/kernel/mips-r2-to-r6-emul.c b/arch/mips/kernel/mips-r2-to-r6-emul.c
index 22dedd6..bd09853 100644
--- a/arch/mips/kernel/mips-r2-to-r6-emul.c
+++ b/arch/mips/kernel/mips-r2-to-r6-emul.c
@@ -899,7 +899,7 @@ static inline int mipsr2_find_op_func(struct pt_regs *regs, u32 inst,
  * mipsr2_decoder: Decode and emulate a MIPS R2 instruction
  * @regs: Process register set
  * @inst: Instruction to decode and emulate
- * @fcr31: Floating Point Control and Status Register returned
+ * @fcr31: Floating Point Control and Status Register Cause bits returned
  */
 int mipsr2_decoder(struct pt_regs *regs, u32 inst, unsigned long *fcr31)
 {
@@ -1172,13 +1172,13 @@ fpu_emul:
 
 		err = fpu_emulator_cop1Handler(regs, &current->thread.fpu, 0,
 					       &fault_addr);
-		*fcr31 = current->thread.fpu.fcr31;
 
 		/*
-		 * We can't allow the emulated instruction to leave any of
-		 * the cause bits set in $fcr31.
+		 * We can't allow the emulated instruction to leave any
+		 * enabled Cause bits set in $fcr31.
 		 */
-		current->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X;
+		*fcr31 = res = mask_fcr31_x(current->thread.fpu.fcr31);
+		current->thread.fpu.fcr31 &= ~res;
 
 		/*
 		 * this is a tricky issue - lose_fpu() uses LL/SC atomics
diff --git a/arch/mips/kernel/ptrace.c b/arch/mips/kernel/ptrace.c
index 6103b24..a92994d 100644
--- a/arch/mips/kernel/ptrace.c
+++ b/arch/mips/kernel/ptrace.c
@@ -79,16 +79,15 @@ void ptrace_disable(struct task_struct *child)
 }
 
 /*
- * Poke at FCSR according to its mask.  Don't set the cause bits as
- * this is currently not handled correctly in FP context restoration
- * and will cause an oops if a corresponding enable bit is set.
+ * Poke at FCSR according to its mask.  Set the Cause bits even
+ * if a corresponding Enable bit is set.  This will be noticed at
+ * the time the thread is switched to and SIGFPE thrown accordingly.
  */
 static void ptrace_setfcr31(struct task_struct *child, u32 value)
 {
 	u32 fcr31;
 	u32 mask;
 
-	value &= ~FPU_CSR_ALL_X;
 	fcr31 = child->thread.fpu.fcr31;
 	mask = boot_cpu_data.fpu_msk31;
 	child->thread.fpu.fcr31 = (value & ~mask) | (fcr31 & mask);
@@ -817,6 +816,7 @@ long arch_ptrace(struct task_struct *child, long request,
 			break;
 #endif
 		case FPC_CSR:
+			init_fp_ctx(child);
 			ptrace_setfcr31(child, data);
 			break;
 		case DSP_BASE ... DSP_BASE + 5: {
diff --git a/arch/mips/kernel/r2300_fpu.S b/arch/mips/kernel/r2300_fpu.S
index b4ac637..918f2f6 100644
--- a/arch/mips/kernel/r2300_fpu.S
+++ b/arch/mips/kernel/r2300_fpu.S
@@ -21,106 +21,84 @@
 #define EX(a,b)							\
 9:	a,##b;							\
 	.section __ex_table,"a";				\
+	PTR	9b,fault;					\
+	.previous
+
+#define EX2(a,b)						\
+9:	a,##b;							\
+	.section __ex_table,"a";				\
 	PTR	9b,bad_stack;					\
+	PTR	9b+4,bad_stack;					\
 	.previous
 
 	.set	noreorder
 	.set	mips1
-	/* Save floating point context */
+
+/**
+ * _save_fp_context() - save FP context from the FPU
+ * @a0 - pointer to fpregs field of sigcontext
+ * @a1 - pointer to fpc_csr field of sigcontext
+ *
+ * Save FP context, including the 32 FP data registers and the FP
+ * control & status register, from the FPU to signal context.
+ */
 LEAF(_save_fp_context)
 	.set	push
 	SET_HARDFLOAT
 	li	v0, 0					# assume success
-	cfc1	t1,fcr31
-	EX(swc1 $f0,(SC_FPREGS+0)(a0))
-	EX(swc1 $f1,(SC_FPREGS+8)(a0))
-	EX(swc1 $f2,(SC_FPREGS+16)(a0))
-	EX(swc1 $f3,(SC_FPREGS+24)(a0))
-	EX(swc1 $f4,(SC_FPREGS+32)(a0))
-	EX(swc1 $f5,(SC_FPREGS+40)(a0))
-	EX(swc1 $f6,(SC_FPREGS+48)(a0))
-	EX(swc1 $f7,(SC_FPREGS+56)(a0))
-	EX(swc1 $f8,(SC_FPREGS+64)(a0))
-	EX(swc1 $f9,(SC_FPREGS+72)(a0))
-	EX(swc1 $f10,(SC_FPREGS+80)(a0))
-	EX(swc1 $f11,(SC_FPREGS+88)(a0))
-	EX(swc1 $f12,(SC_FPREGS+96)(a0))
-	EX(swc1 $f13,(SC_FPREGS+104)(a0))
-	EX(swc1 $f14,(SC_FPREGS+112)(a0))
-	EX(swc1 $f15,(SC_FPREGS+120)(a0))
-	EX(swc1 $f16,(SC_FPREGS+128)(a0))
-	EX(swc1 $f17,(SC_FPREGS+136)(a0))
-	EX(swc1 $f18,(SC_FPREGS+144)(a0))
-	EX(swc1 $f19,(SC_FPREGS+152)(a0))
-	EX(swc1 $f20,(SC_FPREGS+160)(a0))
-	EX(swc1 $f21,(SC_FPREGS+168)(a0))
-	EX(swc1 $f22,(SC_FPREGS+176)(a0))
-	EX(swc1 $f23,(SC_FPREGS+184)(a0))
-	EX(swc1 $f24,(SC_FPREGS+192)(a0))
-	EX(swc1 $f25,(SC_FPREGS+200)(a0))
-	EX(swc1 $f26,(SC_FPREGS+208)(a0))
-	EX(swc1 $f27,(SC_FPREGS+216)(a0))
-	EX(swc1 $f28,(SC_FPREGS+224)(a0))
-	EX(swc1 $f29,(SC_FPREGS+232)(a0))
-	EX(swc1 $f30,(SC_FPREGS+240)(a0))
-	EX(swc1 $f31,(SC_FPREGS+248)(a0))
-	EX(sw	t1,(SC_FPC_CSR)(a0))
-	cfc1	t0,$0				# implementation/version
+	cfc1	t1, fcr31
+	EX2(s.d $f0, 0(a0))
+	EX2(s.d $f2, 16(a0))
+	EX2(s.d $f4, 32(a0))
+	EX2(s.d $f6, 48(a0))
+	EX2(s.d $f8, 64(a0))
+	EX2(s.d $f10, 80(a0))
+	EX2(s.d $f12, 96(a0))
+	EX2(s.d $f14, 112(a0))
+	EX2(s.d $f16, 128(a0))
+	EX2(s.d $f18, 144(a0))
+	EX2(s.d $f20, 160(a0))
+	EX2(s.d $f22, 176(a0))
+	EX2(s.d $f24, 192(a0))
+	EX2(s.d $f26, 208(a0))
+	EX2(s.d $f28, 224(a0))
+	EX2(s.d $f30, 240(a0))
 	jr	ra
+	 EX(sw	t1, (a1))
 	.set	pop
-	.set	nomacro
-	 EX(sw	t0,(SC_FPC_EIR)(a0))
-	.set	macro
 	END(_save_fp_context)
 
-/*
- * Restore FPU state:
- *  - fp gp registers
- *  - cp1 status/control register
+/**
+ * _restore_fp_context() - restore FP context to the FPU
+ * @a0 - pointer to fpregs field of sigcontext
+ * @a1 - pointer to fpc_csr field of sigcontext
  *
- * We base the decision which registers to restore from the signal stack
- * frame on the current content of c0_status, not on the content of the
- * stack frame which might have been changed by the user.
+ * Restore FP context, including the 32 FP data registers and the FP
+ * control & status register, from signal context to the FPU.
  */
 LEAF(_restore_fp_context)
 	.set	push
 	SET_HARDFLOAT
 	li	v0, 0					# assume success
-	EX(lw t0,(SC_FPC_CSR)(a0))
-	EX(lwc1 $f0,(SC_FPREGS+0)(a0))
-	EX(lwc1 $f1,(SC_FPREGS+8)(a0))
-	EX(lwc1 $f2,(SC_FPREGS+16)(a0))
-	EX(lwc1 $f3,(SC_FPREGS+24)(a0))
-	EX(lwc1 $f4,(SC_FPREGS+32)(a0))
-	EX(lwc1 $f5,(SC_FPREGS+40)(a0))
-	EX(lwc1 $f6,(SC_FPREGS+48)(a0))
-	EX(lwc1 $f7,(SC_FPREGS+56)(a0))
-	EX(lwc1 $f8,(SC_FPREGS+64)(a0))
-	EX(lwc1 $f9,(SC_FPREGS+72)(a0))
-	EX(lwc1 $f10,(SC_FPREGS+80)(a0))
-	EX(lwc1 $f11,(SC_FPREGS+88)(a0))
-	EX(lwc1 $f12,(SC_FPREGS+96)(a0))
-	EX(lwc1 $f13,(SC_FPREGS+104)(a0))
-	EX(lwc1 $f14,(SC_FPREGS+112)(a0))
-	EX(lwc1 $f15,(SC_FPREGS+120)(a0))
-	EX(lwc1 $f16,(SC_FPREGS+128)(a0))
-	EX(lwc1 $f17,(SC_FPREGS+136)(a0))
-	EX(lwc1 $f18,(SC_FPREGS+144)(a0))
-	EX(lwc1 $f19,(SC_FPREGS+152)(a0))
-	EX(lwc1 $f20,(SC_FPREGS+160)(a0))
-	EX(lwc1 $f21,(SC_FPREGS+168)(a0))
-	EX(lwc1 $f22,(SC_FPREGS+176)(a0))
-	EX(lwc1 $f23,(SC_FPREGS+184)(a0))
-	EX(lwc1 $f24,(SC_FPREGS+192)(a0))
-	EX(lwc1 $f25,(SC_FPREGS+200)(a0))
-	EX(lwc1 $f26,(SC_FPREGS+208)(a0))
-	EX(lwc1 $f27,(SC_FPREGS+216)(a0))
-	EX(lwc1 $f28,(SC_FPREGS+224)(a0))
-	EX(lwc1 $f29,(SC_FPREGS+232)(a0))
-	EX(lwc1 $f30,(SC_FPREGS+240)(a0))
-	EX(lwc1 $f31,(SC_FPREGS+248)(a0))
+	EX(lw t0, (a1))
+	EX2(l.d $f0, 0(a0))
+	EX2(l.d $f2, 16(a0))
+	EX2(l.d $f4, 32(a0))
+	EX2(l.d $f6, 48(a0))
+	EX2(l.d $f8, 64(a0))
+	EX2(l.d $f10, 80(a0))
+	EX2(l.d $f12, 96(a0))
+	EX2(l.d $f14, 112(a0))
+	EX2(l.d $f16, 128(a0))
+	EX2(l.d $f18, 144(a0))
+	EX2(l.d $f20, 160(a0))
+	EX2(l.d $f22, 176(a0))
+	EX2(l.d $f24, 192(a0))
+	EX2(l.d $f26, 208(a0))
+	EX2(l.d $f28, 224(a0))
+	EX2(l.d $f30, 240(a0))
 	jr	ra
-	 ctc1	t0,fcr31
+	 ctc1	t0, fcr31
 	.set	pop
 	END(_restore_fp_context)
 	.set	reorder
diff --git a/arch/mips/kernel/r6000_fpu.S b/arch/mips/kernel/r6000_fpu.S
index 4707738..9cc7bfa 100644
--- a/arch/mips/kernel/r6000_fpu.S
+++ b/arch/mips/kernel/r6000_fpu.S
@@ -21,7 +21,14 @@
 	.set	push
 	SET_HARDFLOAT
 
-	/* Save floating point context */
+/**
+ * _save_fp_context() - save FP context from the FPU
+ * @a0 - pointer to fpregs field of sigcontext
+ * @a1 - pointer to fpc_csr field of sigcontext
+ *
+ * Save FP context, including the 32 FP data registers and the FP
+ * control & status register, from the FPU to signal context.
+ */
 	LEAF(_save_fp_context)
 	mfc0	t0,CP0_STATUS
 	sll	t0,t0,2
@@ -30,59 +37,59 @@
 
 	cfc1	t1,fcr31
 	/* Store the 16 double precision registers */
-	sdc1	$f0,(SC_FPREGS+0)(a0)
-	sdc1	$f2,(SC_FPREGS+16)(a0)
-	sdc1	$f4,(SC_FPREGS+32)(a0)
-	sdc1	$f6,(SC_FPREGS+48)(a0)
-	sdc1	$f8,(SC_FPREGS+64)(a0)
-	sdc1	$f10,(SC_FPREGS+80)(a0)
-	sdc1	$f12,(SC_FPREGS+96)(a0)
-	sdc1	$f14,(SC_FPREGS+112)(a0)
-	sdc1	$f16,(SC_FPREGS+128)(a0)
-	sdc1	$f18,(SC_FPREGS+144)(a0)
-	sdc1	$f20,(SC_FPREGS+160)(a0)
-	sdc1	$f22,(SC_FPREGS+176)(a0)
-	sdc1	$f24,(SC_FPREGS+192)(a0)
-	sdc1	$f26,(SC_FPREGS+208)(a0)
-	sdc1	$f28,(SC_FPREGS+224)(a0)
-	sdc1	$f30,(SC_FPREGS+240)(a0)
+	sdc1	$f0,0(a0)
+	sdc1	$f2,16(a0)
+	sdc1	$f4,32(a0)
+	sdc1	$f6,48(a0)
+	sdc1	$f8,64(a0)
+	sdc1	$f10,80(a0)
+	sdc1	$f12,96(a0)
+	sdc1	$f14,112(a0)
+	sdc1	$f16,128(a0)
+	sdc1	$f18,144(a0)
+	sdc1	$f20,160(a0)
+	sdc1	$f22,176(a0)
+	sdc1	$f24,192(a0)
+	sdc1	$f26,208(a0)
+	sdc1	$f28,224(a0)
+	sdc1	$f30,240(a0)
 	jr	ra
-	 sw	t0,SC_FPC_CSR(a0)
+	 sw	t0,(a1)
 1:	jr	ra
 	 nop
 	END(_save_fp_context)
 
-/* Restore FPU state:
- *  - fp gp registers
- *  - cp1 status/control register
+/**
+ * _restore_fp_context() - restore FP context to the FPU
+ * @a0 - pointer to fpregs field of sigcontext
+ * @a1 - pointer to fpc_csr field of sigcontext
  *
- * We base the decision which registers to restore from the signal stack
- * frame on the current content of c0_status, not on the content of the
- * stack frame which might have been changed by the user.
+ * Restore FP context, including the 32 FP data registers and the FP
+ * control & status register, from signal context to the FPU.
  */
 	LEAF(_restore_fp_context)
 	mfc0	t0,CP0_STATUS
 	sll	t0,t0,2
 
 	bgez	t0,1f
-	 lw	t0,SC_FPC_CSR(a0)
+	 lw	t0,(a1)
 	/* Restore the 16 double precision registers */
-	ldc1	$f0,(SC_FPREGS+0)(a0)
-	ldc1	$f2,(SC_FPREGS+16)(a0)
-	ldc1	$f4,(SC_FPREGS+32)(a0)
-	ldc1	$f6,(SC_FPREGS+48)(a0)
-	ldc1	$f8,(SC_FPREGS+64)(a0)
-	ldc1	$f10,(SC_FPREGS+80)(a0)
-	ldc1	$f12,(SC_FPREGS+96)(a0)
-	ldc1	$f14,(SC_FPREGS+112)(a0)
-	ldc1	$f16,(SC_FPREGS+128)(a0)
-	ldc1	$f18,(SC_FPREGS+144)(a0)
-	ldc1	$f20,(SC_FPREGS+160)(a0)
-	ldc1	$f22,(SC_FPREGS+176)(a0)
-	ldc1	$f24,(SC_FPREGS+192)(a0)
-	ldc1	$f26,(SC_FPREGS+208)(a0)
-	ldc1	$f28,(SC_FPREGS+224)(a0)
-	ldc1	$f30,(SC_FPREGS+240)(a0)
+	ldc1	$f0,0(a0)
+	ldc1	$f2,16(a0)
+	ldc1	$f4,32(a0)
+	ldc1	$f6,48(a0)
+	ldc1	$f8,64(a0)
+	ldc1	$f10,80(a0)
+	ldc1	$f12,96(a0)
+	ldc1	$f14,112(a0)
+	ldc1	$f16,128(a0)
+	ldc1	$f18,144(a0)
+	ldc1	$f20,160(a0)
+	ldc1	$f22,176(a0)
+	ldc1	$f24,192(a0)
+	ldc1	$f26,208(a0)
+	ldc1	$f28,224(a0)
+	ldc1	$f30,240(a0)
 	jr	ra
 	 ctc1	t0,fcr31
 1:	jr	ra
diff --git a/arch/mips/kernel/relocate.c b/arch/mips/kernel/relocate.c
index ca1cc30..1958910 100644
--- a/arch/mips/kernel/relocate.c
+++ b/arch/mips/kernel/relocate.c
@@ -200,7 +200,7 @@ static inline __init unsigned long get_random_boot(void)
 
 #if defined(CONFIG_USE_OF)
 	/* Get any additional entropy passed in device tree */
-	{
+	if (initial_boot_params) {
 		int node, len;
 		u64 *prop;
 
diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
index 0d57909..f66e5ce 100644
--- a/arch/mips/kernel/setup.c
+++ b/arch/mips/kernel/setup.c
@@ -368,6 +368,19 @@ static void __init bootmem_init(void)
 		end = PFN_DOWN(boot_mem_map.map[i].addr
 				+ boot_mem_map.map[i].size);
 
+#ifndef CONFIG_HIGHMEM
+		/*
+		 * Skip highmem here so we get an accurate max_low_pfn if low
+		 * memory stops short of high memory.
+		 * If the region overlaps HIGHMEM_START, end is clipped so
+		 * max_pfn excludes the highmem portion.
+		 */
+		if (start >= PFN_DOWN(HIGHMEM_START))
+			continue;
+		if (end > PFN_DOWN(HIGHMEM_START))
+			end = PFN_DOWN(HIGHMEM_START);
+#endif
+
 		if (end > max_low_pfn)
 			max_low_pfn = end;
 		if (start < min_low_pfn)
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 1f5fdee..3905003 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -156,7 +156,7 @@ static void show_backtrace(struct task_struct *task, const struct pt_regs *regs)
 		print_ip_sym(pc);
 		pc = unwind_stack(task, &sp, pc, &ra);
 	} while (pc);
-	printk("\n");
+	pr_cont("\n");
 }
 
 /*
@@ -174,22 +174,24 @@ static void show_stacktrace(struct task_struct *task,
 	printk("Stack :");
 	i = 0;
 	while ((unsigned long) sp & (PAGE_SIZE - 1)) {
-		if (i && ((i % (64 / field)) == 0))
-			printk("\n	 ");
+		if (i && ((i % (64 / field)) == 0)) {
+			pr_cont("\n");
+			printk("       ");
+		}
 		if (i > 39) {
-			printk(" ...");
+			pr_cont(" ...");
 			break;
 		}
 
 		if (__get_user(stackdata, sp++)) {
-			printk(" (Bad stack address)");
+			pr_cont(" (Bad stack address)");
 			break;
 		}
 
-		printk(" %0*lx", field, stackdata);
+		pr_cont(" %0*lx", field, stackdata);
 		i++;
 	}
-	printk("\n");
+	pr_cont("\n");
 	show_backtrace(task, regs);
 }
 
@@ -229,18 +231,19 @@ static void show_code(unsigned int __user *pc)
 	long i;
 	unsigned short __user *pc16 = NULL;
 
-	printk("\nCode:");
+	printk("Code:");
 
 	if ((unsigned long)pc & 1)
 		pc16 = (unsigned short __user *)((unsigned long)pc & ~1);
 	for(i = -3 ; i < 6 ; i++) {
 		unsigned int insn;
 		if (pc16 ? __get_user(insn, pc16 + i) : __get_user(insn, pc + i)) {
-			printk(" (Bad address in epc)\n");
+			pr_cont(" (Bad address in epc)\n");
 			break;
 		}
-		printk("%c%0*x%c", (i?' ':'<'), pc16 ? 4 : 8, insn, (i?' ':'>'));
+		pr_cont("%c%0*x%c", (i?' ':'<'), pc16 ? 4 : 8, insn, (i?' ':'>'));
 	}
+	pr_cont("\n");
 }
 
 static void __show_regs(const struct pt_regs *regs)
@@ -259,15 +262,15 @@ static void __show_regs(const struct pt_regs *regs)
 		if ((i % 4) == 0)
 			printk("$%2d   :", i);
 		if (i == 0)
-			printk(" %0*lx", field, 0UL);
+			pr_cont(" %0*lx", field, 0UL);
 		else if (i == 26 || i == 27)
-			printk(" %*s", field, "");
+			pr_cont(" %*s", field, "");
 		else
-			printk(" %0*lx", field, regs->regs[i]);
+			pr_cont(" %0*lx", field, regs->regs[i]);
 
 		i++;
 		if ((i % 4) == 0)
-			printk("\n");
+			pr_cont("\n");
 	}
 
 #ifdef CONFIG_CPU_HAS_SMARTMIPS
@@ -288,46 +291,46 @@ static void __show_regs(const struct pt_regs *regs)
 
 	if (cpu_has_3kex) {
 		if (regs->cp0_status & ST0_KUO)
-			printk("KUo ");
+			pr_cont("KUo ");
 		if (regs->cp0_status & ST0_IEO)
-			printk("IEo ");
+			pr_cont("IEo ");
 		if (regs->cp0_status & ST0_KUP)
-			printk("KUp ");
+			pr_cont("KUp ");
 		if (regs->cp0_status & ST0_IEP)
-			printk("IEp ");
+			pr_cont("IEp ");
 		if (regs->cp0_status & ST0_KUC)
-			printk("KUc ");
+			pr_cont("KUc ");
 		if (regs->cp0_status & ST0_IEC)
-			printk("IEc ");
+			pr_cont("IEc ");
 	} else if (cpu_has_4kex) {
 		if (regs->cp0_status & ST0_KX)
-			printk("KX ");
+			pr_cont("KX ");
 		if (regs->cp0_status & ST0_SX)
-			printk("SX ");
+			pr_cont("SX ");
 		if (regs->cp0_status & ST0_UX)
-			printk("UX ");
+			pr_cont("UX ");
 		switch (regs->cp0_status & ST0_KSU) {
 		case KSU_USER:
-			printk("USER ");
+			pr_cont("USER ");
 			break;
 		case KSU_SUPERVISOR:
-			printk("SUPERVISOR ");
+			pr_cont("SUPERVISOR ");
 			break;
 		case KSU_KERNEL:
-			printk("KERNEL ");
+			pr_cont("KERNEL ");
 			break;
 		default:
-			printk("BAD_MODE ");
+			pr_cont("BAD_MODE ");
 			break;
 		}
 		if (regs->cp0_status & ST0_ERL)
-			printk("ERL ");
+			pr_cont("ERL ");
 		if (regs->cp0_status & ST0_EXL)
-			printk("EXL ");
+			pr_cont("EXL ");
 		if (regs->cp0_status & ST0_IE)
-			printk("IE ");
+			pr_cont("IE ");
 	}
-	printk("\n");
+	pr_cont("\n");
 
 	exccode = (cause & CAUSEF_EXCCODE) >> CAUSEB_EXCCODE;
 	printk("Cause : %08x (ExcCode %02x)\n", cause, exccode);
@@ -705,6 +708,32 @@ asmlinkage void do_ov(struct pt_regs *regs)
 	exception_exit(prev_state);
 }
 
+/*
+ * Send SIGFPE according to FCSR Cause bits, which must have already
+ * been masked against Enable bits.  This is impotant as Inexact can
+ * happen together with Overflow or Underflow, and `ptrace' can set
+ * any bits.
+ */
+void force_fcr31_sig(unsigned long fcr31, void __user *fault_addr,
+		     struct task_struct *tsk)
+{
+	struct siginfo si = { .si_addr = fault_addr, .si_signo = SIGFPE };
+
+	if (fcr31 & FPU_CSR_INV_X)
+		si.si_code = FPE_FLTINV;
+	else if (fcr31 & FPU_CSR_DIV_X)
+		si.si_code = FPE_FLTDIV;
+	else if (fcr31 & FPU_CSR_OVF_X)
+		si.si_code = FPE_FLTOVF;
+	else if (fcr31 & FPU_CSR_UDF_X)
+		si.si_code = FPE_FLTUND;
+	else if (fcr31 & FPU_CSR_INE_X)
+		si.si_code = FPE_FLTRES;
+	else
+		si.si_code = __SI_FAULT;
+	force_sig_info(SIGFPE, &si, tsk);
+}
+
 int process_fpemu_return(int sig, void __user *fault_addr, unsigned long fcr31)
 {
 	struct siginfo si = { 0 };
@@ -715,27 +744,7 @@ int process_fpemu_return(int sig, void __user *fault_addr, unsigned long fcr31)
 		return 0;
 
 	case SIGFPE:
-		si.si_addr = fault_addr;
-		si.si_signo = sig;
-		/*
-		 * Inexact can happen together with Overflow or Underflow.
-		 * Respect the mask to deliver the correct exception.
-		 */
-		fcr31 &= (fcr31 & FPU_CSR_ALL_E) <<
-			 (ffs(FPU_CSR_ALL_X) - ffs(FPU_CSR_ALL_E));
-		if (fcr31 & FPU_CSR_INV_X)
-			si.si_code = FPE_FLTINV;
-		else if (fcr31 & FPU_CSR_DIV_X)
-			si.si_code = FPE_FLTDIV;
-		else if (fcr31 & FPU_CSR_OVF_X)
-			si.si_code = FPE_FLTOVF;
-		else if (fcr31 & FPU_CSR_UDF_X)
-			si.si_code = FPE_FLTUND;
-		else if (fcr31 & FPU_CSR_INE_X)
-			si.si_code = FPE_FLTRES;
-		else
-			si.si_code = __SI_FAULT;
-		force_sig_info(sig, &si, current);
+		force_fcr31_sig(fcr31, fault_addr, current);
 		return 1;
 
 	case SIGBUS:
@@ -799,13 +808,13 @@ static int simulate_fp(struct pt_regs *regs, unsigned int opcode,
 	/* Run the emulator */
 	sig = fpu_emulator_cop1Handler(regs, &current->thread.fpu, 1,
 				       &fault_addr);
-	fcr31 = current->thread.fpu.fcr31;
 
 	/*
-	 * We can't allow the emulated instruction to leave any of
-	 * the cause bits set in $fcr31.
+	 * We can't allow the emulated instruction to leave any
+	 * enabled Cause bits set in $fcr31.
 	 */
-	current->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X;
+	fcr31 = mask_fcr31_x(current->thread.fpu.fcr31);
+	current->thread.fpu.fcr31 &= ~fcr31;
 
 	/* Restore the hardware register state */
 	own_fpu(1);
@@ -831,7 +840,7 @@ asmlinkage void do_fpe(struct pt_regs *regs, unsigned long fcr31)
 		goto out;
 
 	/* Clear FCSR.Cause before enabling interrupts */
-	write_32bit_cp1_register(CP1_STATUS, fcr31 & ~FPU_CSR_ALL_X);
+	write_32bit_cp1_register(CP1_STATUS, fcr31 & ~mask_fcr31_x(fcr31));
 	local_irq_enable();
 
 	die_if_kernel("FP exception in kernel code", regs);
@@ -853,13 +862,13 @@ asmlinkage void do_fpe(struct pt_regs *regs, unsigned long fcr31)
 		/* Run the emulator */
 		sig = fpu_emulator_cop1Handler(regs, &current->thread.fpu, 1,
 					       &fault_addr);
-		fcr31 = current->thread.fpu.fcr31;
 
 		/*
-		 * We can't allow the emulated instruction to leave any of
-		 * the cause bits set in $fcr31.
+		 * We can't allow the emulated instruction to leave any
+		 * enabled Cause bits set in $fcr31.
 		 */
-		current->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X;
+		fcr31 = mask_fcr31_x(current->thread.fpu.fcr31);
+		current->thread.fpu.fcr31 &= ~fcr31;
 
 		/* Restore the hardware register state */
 		own_fpu(1);	/* Using the FPU again.	 */
@@ -1424,13 +1433,13 @@ asmlinkage void do_cpu(struct pt_regs *regs)
 
 		sig = fpu_emulator_cop1Handler(regs, &current->thread.fpu, 0,
 					       &fault_addr);
-		fcr31 = current->thread.fpu.fcr31;
 
 		/*
 		 * We can't allow the emulated instruction to leave
-		 * any of the cause bits set in $fcr31.
+		 * any enabled Cause bits set in $fcr31.
 		 */
-		current->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X;
+		fcr31 = mask_fcr31_x(current->thread.fpu.fcr31);
+		current->thread.fpu.fcr31 &= ~fcr31;
 
 		/* Send a signal if required.  */
 		if (!process_fpemu_return(sig, fault_addr, fcr31) && !err)
diff --git a/arch/mips/lib/dump_tlb.c b/arch/mips/lib/dump_tlb.c
index 0f80b93..6eb50a7 100644
--- a/arch/mips/lib/dump_tlb.c
+++ b/arch/mips/lib/dump_tlb.c
@@ -135,42 +135,42 @@ static void dump_tlb(int first, int last)
 		c0 = (entrylo0 & ENTRYLO_C) >> ENTRYLO_C_SHIFT;
 		c1 = (entrylo1 & ENTRYLO_C) >> ENTRYLO_C_SHIFT;
 
-		printk("va=%0*lx asid=%0*lx",
-		       vwidth, (entryhi & ~0x1fffUL),
-		       asidwidth, entryhi & asidmask);
+		pr_cont("va=%0*lx asid=%0*lx",
+			vwidth, (entryhi & ~0x1fffUL),
+			asidwidth, entryhi & asidmask);
 		if (cpu_has_guestid)
-			printk(" gid=%02lx",
-			       (guestctl1 & MIPS_GCTL1_RID)
+			pr_cont(" gid=%02lx",
+				(guestctl1 & MIPS_GCTL1_RID)
 					>> MIPS_GCTL1_RID_SHIFT);
 		/* RI/XI are in awkward places, so mask them off separately */
 		pa = entrylo0 & ~(MIPS_ENTRYLO_RI | MIPS_ENTRYLO_XI);
 		if (xpa)
 			pa |= (unsigned long long)readx_c0_entrylo0() << 30;
 		pa = (pa << 6) & PAGE_MASK;
-		printk("\n\t[");
+		pr_cont("\n\t[");
 		if (cpu_has_rixi)
-			printk("ri=%d xi=%d ",
-			       (entrylo0 & MIPS_ENTRYLO_RI) ? 1 : 0,
-			       (entrylo0 & MIPS_ENTRYLO_XI) ? 1 : 0);
-		printk("pa=%0*llx c=%d d=%d v=%d g=%d] [",
-		       pwidth, pa, c0,
-		       (entrylo0 & ENTRYLO_D) ? 1 : 0,
-		       (entrylo0 & ENTRYLO_V) ? 1 : 0,
-		       (entrylo0 & ENTRYLO_G) ? 1 : 0);
+			pr_cont("ri=%d xi=%d ",
+				(entrylo0 & MIPS_ENTRYLO_RI) ? 1 : 0,
+				(entrylo0 & MIPS_ENTRYLO_XI) ? 1 : 0);
+		pr_cont("pa=%0*llx c=%d d=%d v=%d g=%d] [",
+			pwidth, pa, c0,
+			(entrylo0 & ENTRYLO_D) ? 1 : 0,
+			(entrylo0 & ENTRYLO_V) ? 1 : 0,
+			(entrylo0 & ENTRYLO_G) ? 1 : 0);
 		/* RI/XI are in awkward places, so mask them off separately */
 		pa = entrylo1 & ~(MIPS_ENTRYLO_RI | MIPS_ENTRYLO_XI);
 		if (xpa)
 			pa |= (unsigned long long)readx_c0_entrylo1() << 30;
 		pa = (pa << 6) & PAGE_MASK;
 		if (cpu_has_rixi)
-			printk("ri=%d xi=%d ",
-			       (entrylo1 & MIPS_ENTRYLO_RI) ? 1 : 0,
-			       (entrylo1 & MIPS_ENTRYLO_XI) ? 1 : 0);
-		printk("pa=%0*llx c=%d d=%d v=%d g=%d]\n",
-		       pwidth, pa, c1,
-		       (entrylo1 & ENTRYLO_D) ? 1 : 0,
-		       (entrylo1 & ENTRYLO_V) ? 1 : 0,
-		       (entrylo1 & ENTRYLO_G) ? 1 : 0);
+			pr_cont("ri=%d xi=%d ",
+				(entrylo1 & MIPS_ENTRYLO_RI) ? 1 : 0,
+				(entrylo1 & MIPS_ENTRYLO_XI) ? 1 : 0);
+		pr_cont("pa=%0*llx c=%d d=%d v=%d g=%d]\n",
+			pwidth, pa, c1,
+			(entrylo1 & ENTRYLO_D) ? 1 : 0,
+			(entrylo1 & ENTRYLO_V) ? 1 : 0,
+			(entrylo1 & ENTRYLO_G) ? 1 : 0);
 	}
 	printk("\n");
 
diff --git a/arch/mips/lib/r3k_dump_tlb.c b/arch/mips/lib/r3k_dump_tlb.c
index 744f4a7..85b4086 100644
--- a/arch/mips/lib/r3k_dump_tlb.c
+++ b/arch/mips/lib/r3k_dump_tlb.c
@@ -53,15 +53,15 @@ static void dump_tlb(int first, int last)
 			 */
 			printk("Index: %2d ", i);
 
-			printk("va=%08lx asid=%08lx"
-			       "  [pa=%06lx n=%d d=%d v=%d g=%d]",
-			       entryhi & PAGE_MASK,
-			       entryhi & asid_mask,
-			       entrylo0 & PAGE_MASK,
-			       (entrylo0 & R3K_ENTRYLO_N) ? 1 : 0,
-			       (entrylo0 & R3K_ENTRYLO_D) ? 1 : 0,
-			       (entrylo0 & R3K_ENTRYLO_V) ? 1 : 0,
-			       (entrylo0 & R3K_ENTRYLO_G) ? 1 : 0);
+			pr_cont("va=%08lx asid=%08lx"
+				"  [pa=%06lx n=%d d=%d v=%d g=%d]",
+				entryhi & PAGE_MASK,
+				entryhi & asid_mask,
+				entrylo0 & PAGE_MASK,
+				(entrylo0 & R3K_ENTRYLO_N) ? 1 : 0,
+				(entrylo0 & R3K_ENTRYLO_D) ? 1 : 0,
+				(entrylo0 & R3K_ENTRYLO_V) ? 1 : 0,
+				(entrylo0 & R3K_ENTRYLO_G) ? 1 : 0);
 		}
 	}
 	printk("\n");