[PATCH 3.17 002/122] MIPS: lib: memcpy: Restore NOP on delay slot before returning to caller

[PATCH 3.17 002/122] MIPS: lib: memcpy: Restore NOP on delay slot before returning to caller

[Greg Kroah-Hartman]

3.17-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Markos Chandras <markos.chandras@imgtec.com>

commit 51b1029d9966060c6ad02030e6f251425b4f06c1 upstream.

Commit cf62a8b8134dd3 ("MIPS: lib: memcpy: Use macro to build the
copy_user code") switched to a macro in order to build the memcpy
symbols in preparation for the EVA support. However, this commit
also removed the NOP instruction after the 'jr ra' when returning
back to the caller. This had no visible side-effects since the next
instruction was a load to the t0 register which was already in the
clobbered list, but it may have undesired effects in the future
if some other code is introduced in between the .Ldone and
the .Ll_exc_copy labels.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8512/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/mips/lib/memcpy.S |    1 +
 1 file changed, 1 insertion(+)

--- a/arch/mips/lib/memcpy.S
+++ b/arch/mips/lib/memcpy.S
@@ -503,6 +503,7 @@
 	STOREB(t0, NBYTES-2(dst), .Ls_exc_p1\@)
 .Ldone\@:
 	jr	ra
+	 nop
 	.if __memcpy == 1
 	END(memcpy)
 	.set __memcpy, 0

[PATCH 3.17 003/122] MIPS: oprofile: Fix backtrace on 64-bit kernel

[Greg Kroah-Hartman]

3.17-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Aaro Koskinen <aaro.koskinen@nsn.com>

commit bbaf113a481b6ce32444c125807ad3618643ce57 upstream.

Fix incorrect cast that always results in wrong address for the new
frame on 64-bit kernels.

Signed-off-by: Aaro Koskinen <aaro.koskinen@nsn.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8110/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/mips/oprofile/backtrace.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/mips/oprofile/backtrace.c
+++ b/arch/mips/oprofile/backtrace.c
@@ -92,7 +92,7 @@ static inline int unwind_user_frame(stru
 				/* This marks the end of the previous function,
 				   which means we overran. */
 				break;
-			stack_size = (unsigned) stack_adjustment;
+			stack_size = (unsigned long) stack_adjustment;
 		} else if (is_ra_save_ins(&ip)) {
 			int ra_slot = ip.i_format.simmediate;
 			if (ra_slot < 0)

[PATCH 3.17 004/122] MIPS: tlb-r4k: Add missing HTW stop/start sequences

[Greg Kroah-Hartman]

3.17-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Markos Chandras <markos.chandras@imgtec.com>

commit 6a8dff6ab16c903b0d8ef5fbf21543f39bf5d675 upstream.

HTW needs to stop and start again whenever the EntryHI register
changes otherwise an inflight HTW operation might use the new
EntryHI register for updating an old entry and that could lead
to crashes or even a machine check exception. We fix this by
ensuring the HTW has stop whenever the EntryHI register is about
to change

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8511/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/mips/mm/tlb-r4k.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/arch/mips/mm/tlb-r4k.c
+++ b/arch/mips/mm/tlb-r4k.c
@@ -299,6 +299,7 @@ void __update_tlb(struct vm_area_struct
 
 	local_irq_save(flags);
 
+	htw_stop();
 	pid = read_c0_entryhi() & ASID_MASK;
 	address &= (PAGE_MASK << 1);
 	write_c0_entryhi(address | pid);
@@ -346,6 +347,7 @@ void __update_tlb(struct vm_area_struct
 			tlb_write_indexed();
 	}
 	tlbw_use_hazard();
+	htw_start();
 	flush_itlb_vm(vma);
 	local_irq_restore(flags);
 }
@@ -422,6 +424,7 @@ __init int add_temporary_entry(unsigned
 
 	local_irq_save(flags);
 	/* Save old context and create impossible VPN2 value */
+	htw_stop();
 	old_ctx = read_c0_entryhi();
 	old_pagemask = read_c0_pagemask();
 	wired = read_c0_wired();
@@ -443,6 +446,7 @@ __init int add_temporary_entry(unsigned
 
 	write_c0_entryhi(old_ctx);
 	write_c0_pagemask(old_pagemask);
+	htw_start();
 out:
 	local_irq_restore(flags);
 	return ret;

[PATCH 3.17 005/122] MIPS: Loongson3: Fix __node_distances undefined error

[Greg Kroah-Hartman]

3.17-stable review patch.  If anyone has any objections, please let me know.

------------------

From: James Cowgill <James.Cowgill@imgtec.com>

commit 21255dad9dffa4407cab866f5561cb9568f7f7d8 upstream.

export the __node_distances symbol in the loongson3 numa code to fix the
build error:

  Building modules, stage 2.
  MODPOST 221 modules
ERROR: "__node_distances" [drivers/block/nvme.ko] undefined!
scripts/Makefile.modpost:90: recipe for target '__modpost' failed

when building the kernel with:
 CONFIG_CPU_LOONGSON3=y
 CONFIG_NUMA=y
 CONFIG_BLK_DEV_NVME=m

Signed-off-by: James Cowgill <James.Cowgill@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Huacai Chen <chenhc@lemote.com>
Cc: linux-mips@linux-mips.org
Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Patchwork: https://patchwork.linux-mips.org/patch/8444/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/mips/loongson/loongson-3/numa.c |    1 +
 1 file changed, 1 insertion(+)

--- a/arch/mips/loongson/loongson-3/numa.c
+++ b/arch/mips/loongson/loongson-3/numa.c
@@ -33,6 +33,7 @@
 
 static struct node_data prealloc__node_data[MAX_NUMNODES];
 unsigned char __node_distances[MAX_NUMNODES][MAX_NUMNODES];
+EXPORT_SYMBOL(__node_distances);
 struct node_data *__node_data[MAX_NUMNODES];
 EXPORT_SYMBOL(__node_data);
 

[PATCH 3.17 006/122] MIPS: asm: uaccess: Add v1 register to clobber list on EVA

[Greg Kroah-Hartman]

3.17-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Markos Chandras <markos.chandras@imgtec.com>

commit 58563817cfed0432e9a54476d5fc6c3aeba475e4 upstream.

When EVA is turned on and prefetching is being used in memcpy.S,
the v1 register is being used as a helper register to the PREFE
instruction. However, v1 ($3) was not in the clobber list, which
means that the compiler did not preserve it across function calls,
and that could corrupt the value of the register leading to all
sorts of userland crashes. We fix this problem by using the
DADDI_SCRATCH macro to define the clobbered register when
CONFIG_EVA && CONFIG_CPU_HAS_PREFETCH are enabled.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8510/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/mips/include/asm/uaccess.h |    7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

--- a/arch/mips/include/asm/uaccess.h
+++ b/arch/mips/include/asm/uaccess.h
@@ -773,10 +773,11 @@ extern void __put_user_unaligned_unknown
 	"jal\t" #destination "\n\t"
 #endif
 
-#ifndef CONFIG_CPU_DADDI_WORKAROUNDS
-#define DADDI_SCRATCH "$0"
-#else
+#if defined(CONFIG_CPU_DADDI_WORKAROUNDS) || (defined(CONFIG_EVA) &&	\
+					      defined(CONFIG_CPU_HAS_PREFETCH))
 #define DADDI_SCRATCH "$3"
+#else
+#define DADDI_SCRATCH "$0"
 #endif
 
 extern size_t __copy_user(void *__to, const void *__from, size_t __n);

[PATCH 3.17 007/122] MIPS: cpu-probe: Set the FTLB probability bit on supported cores

[Greg Kroah-Hartman]

3.17-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Markos Chandras <markos.chandras@imgtec.com>

commit cf0a8aa0226da5de88011e7f30eff22a894b2f49 upstream.

Make use of the Config6/FLTBP bit to set the probability of a TLBWR
instruction to hit the FTLB or the VTLB. A value of 0 (which may be
the default value on certain cores, such as proAptiv or P5600)
means that a TLBWR instruction will never hit the VTLB which
leads to performance limitations since it effectively decreases
the number of available TLB slots.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8368/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/mips/include/asm/mipsregs.h |    2 ++
 arch/mips/kernel/cpu-probe.c     |   33 ++++++++++++++++++++++++++++++++-
 2 files changed, 34 insertions(+), 1 deletion(-)

--- a/arch/mips/include/asm/mipsregs.h
+++ b/arch/mips/include/asm/mipsregs.h
@@ -661,6 +661,8 @@
 #define MIPS_CONF6_SYND		(_ULCAST_(1) << 13)
 /* proAptiv FTLB on/off bit */
 #define MIPS_CONF6_FTLBEN	(_ULCAST_(1) << 15)
+/* FTLB probability bits */
+#define MIPS_CONF6_FTLBP_SHIFT	(16)
 
 #define MIPS_CONF7_WII		(_ULCAST_(1) << 31)
 
--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -192,6 +192,32 @@ static void set_isa(struct cpuinfo_mips
 static char unknown_isa[] = KERN_ERR \
 	"Unsupported ISA type, c0.config0: %d.";
 
+static unsigned int calculate_ftlb_probability(struct cpuinfo_mips *c)
+{
+
+	unsigned int probability = c->tlbsize / c->tlbsizevtlb;
+
+	/*
+	 * 0 = All TLBWR instructions go to FTLB
+	 * 1 = 15:1: For every 16 TBLWR instructions, 15 go to the
+	 * FTLB and 1 goes to the VTLB.
+	 * 2 = 7:1: As above with 7:1 ratio.
+	 * 3 = 3:1: As above with 3:1 ratio.
+	 *
+	 * Use the linear midpoint as the probability threshold.
+	 */
+	if (probability >= 12)
+		return 1;
+	else if (probability >= 6)
+		return 2;
+	else
+		/*
+		 * So FTLB is less than 4 times bigger than VTLB.
+		 * A 3:1 ratio can still be useful though.
+		 */
+		return 3;
+}
+
 static void set_ftlb_enable(struct cpuinfo_mips *c, int enable)
 {
 	unsigned int config6;
@@ -202,9 +228,14 @@ static void set_ftlb_enable(struct cpuin
 	case CPU_P5600:
 		/* proAptiv & related cores use Config6 to enable the FTLB */
 		config6 = read_c0_config6();
+		/* Clear the old probability value */
+		config6 &= ~(3 << MIPS_CONF6_FTLBP_SHIFT);
 		if (enable)
 			/* Enable FTLB */
-			write_c0_config6(config6 | MIPS_CONF6_FTLBEN);
+			write_c0_config6(config6 |
+					 (calculate_ftlb_probability(c)
+					  << MIPS_CONF6_FTLBP_SHIFT)
+					 | MIPS_CONF6_FTLBEN);
 		else
 			/* Disable FTLB */
 			write_c0_config6(config6 &  ~MIPS_CONF6_FTLBEN);

[PATCH 3.17 008/122] MIPS: fix EVA & non-SMP non-FPU FP context signal handling

[Greg Kroah-Hartman]

3.17-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Paul Burton <paul.burton@imgtec.com>

commit 14fa12df1d6bc1d3389a0fa842e0ebd8e8a9af26 upstream.

The save_fp_context & restore_fp_context pointers were being assigned
to the wrong variables if either:

  - The kernel is configured for UP & runs on a system without an FPU,
    since b2ead5282885 "MIPS: Move & rename
    fpu_emulator_{save,restore}_context".

  - The kernel is configured for EVA, since ca750649e08c "MIPS: kernel:
    signal: Prevent save/restore FPU context in user memory".

This would lead to FP context being clobbered incorrectly when setting
up a sigcontext, then the garbage values being saved uselessly when
returning from the signal.

Fix by swapping the pointer assignments appropriately.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8230/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/mips/kernel/signal.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

--- a/arch/mips/kernel/signal.c
+++ b/arch/mips/kernel/signal.c
@@ -658,13 +658,13 @@ static int signal_setup(void)
 		save_fp_context = _save_fp_context;
 		restore_fp_context = _restore_fp_context;
 	} else {
-		save_fp_context = copy_fp_from_sigcontext;
-		restore_fp_context = copy_fp_to_sigcontext;
+		save_fp_context = copy_fp_to_sigcontext;
+		restore_fp_context = copy_fp_from_sigcontext;
 	}
 #endif /* CONFIG_SMP */
 #else
-	save_fp_context = copy_fp_from_sigcontext;;
-	restore_fp_context = copy_fp_to_sigcontext;
+	save_fp_context = copy_fp_to_sigcontext;
+	restore_fp_context = copy_fp_from_sigcontext;
 #endif
 
 	return 0;

[PATCH 3.17 009/122] MIPS: r4kcache: Add EVA case for protected_writeback_dcache_line

[Greg Kroah-Hartman]

3.17-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Markos Chandras <markos.chandras@imgtec.com>

commit 83fd43449baaf88fe5c03dd0081a062041837c51 upstream.

Commit de8974e3f76c0 ("MIPS: asm: r4kcache: Add EVA cache flushing
functions") added cache function for EVA using the cachee instruction.
However, it didn't add a case for the protected_writeback_dcache_line.
mips_dsemul() calls r4k_flush_cache_sigtramp() which in turn uses
the protected_writeback_dcache_line() to flush the trampoline code
back to memory. This used the wrong "cache" instruction leading to
random userland crashes on non-FPU cores.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8331/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/mips/include/asm/r4kcache.h |    4 ++++
 1 file changed, 4 insertions(+)

--- a/arch/mips/include/asm/r4kcache.h
+++ b/arch/mips/include/asm/r4kcache.h
@@ -257,7 +257,11 @@ static inline void protected_flush_icach
  */
 static inline void protected_writeback_dcache_line(unsigned long addr)
 {
+#ifdef CONFIG_EVA
+	protected_cachee_op(Hit_Writeback_Inv_D, addr);
+#else
 	protected_cache_op(Hit_Writeback_Inv_D, addr);
+#endif
 }
 
 static inline void protected_writeback_scache_line(unsigned long addr)

[PATCH 3.17 010/122] MIPS: tlbex: Fix potential HTW race on TLBL/M/S handlers

[Greg Kroah-Hartman]

3.17-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>

commit 070e76cb3ffe43f6855492e77c96680c562598f0 upstream.

There is a potential race when probing the TLB in TLBL/M/S exception
handlers for a matching entry. Between the time we hit a TLBL/S/M
exception and the time we get to execute the TLBP instruction, the
HTW may have replaced the TLB entry we are interested in hence the TLB
probe may fail. However, in the existing handlers, we never checked the
status of the TLBP (ie check the result in the C0/Index register). We
fix this by adding such a check when the core implements the HTW. If
we couldn't find a matching entry, we return back and try again.

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8599/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/mips/mm/tlbex.c |   10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

--- a/arch/mips/mm/tlbex.c
+++ b/arch/mips/mm/tlbex.c
@@ -1872,8 +1872,16 @@ build_r4000_tlbchange_handler_head(u32 *
 	uasm_l_smp_pgtable_change(l, *p);
 #endif
 	iPTE_LW(p, wr.r1, wr.r2); /* get even pte */
-	if (!m4kc_tlbp_war())
+	if (!m4kc_tlbp_war()) {
 		build_tlb_probe_entry(p);
+		if (cpu_has_htw) {
+			/* race condition happens, leaving */
+			uasm_i_ehb(p);
+			uasm_i_mfc0(p, wr.r3, C0_INDEX);
+			uasm_il_bltz(p, r, wr.r3, label_leave);
+			uasm_i_nop(p);
+		}
+	}
 	return wr;
 }
 

[PATCH 3.17 011/122] MIPS: Loongson: Make platform serial setup always built-in.

[Greg Kroah-Hartman]

3.17-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Aaro Koskinen <aaro.koskinen@iki.fi>

commit 26927f76499849e095714452b8a4e09350f6a3b9 upstream.

If SERIAL_8250 is compiled as a module, the platform specific setup
for Loongson will be a module too, and it will not work very well.
At least on Loongson 3 it will trigger a build failure,
since loongson_sysconf is not exported to modules.

Fix by making the platform specific serial code always built-in.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Reported-by: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Markos Chandras <Markos.Chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/8533/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/mips/loongson/common/Makefile |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/arch/mips/loongson/common/Makefile
+++ b/arch/mips/loongson/common/Makefile
@@ -11,7 +11,8 @@ obj-$(CONFIG_PCI) += pci.o
 # Serial port support
 #
 obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
-obj-$(CONFIG_SERIAL_8250) += serial.o
+loongson-serial-$(CONFIG_SERIAL_8250) := serial.o
+obj-y += $(loongson-serial-m) $(loongson-serial-y)
 obj-$(CONFIG_LOONGSON_UART_BASE) += uart_base.o
 obj-$(CONFIG_LOONGSON_MC146818) += rtc.o