[PATCH 0/4] ARM: patches for randconfig build errors

Hi Russell,

I've done some testing with the experimental multiplatform tree
and that uncovered a few preexisting bugs. Here are the ones
that should go through your tree. Please have a look to
see if the fixes make sense. I can put the patches in the patch
tracker or send you a pull request then.

	Arnd
---
Cc: Jon Medhurst <redacted>
Cc: Leif Lindholm <redacted>
Cc: Linus Walleij <redacted>
Cc: Magnus Damm <redacted>
Cc: Nicolas Pitre <redacted>
Cc: Rafael J. Wysocki <redacted>
Cc: Russell King <redacted>
Cc: Shinya Kuribayashi <redacted>
Cc: Stephen Boyd <redacted>
Cc: Thomas Gleixner <redacted>
Cc: Will Deacon <redacted>

Arnd Bergmann (4):
  ARM: export read_current_timer
  ARM: allow PID_IN_CONTEXTIDR only for ARMv7
  ARM: export set_irq_flags/irq_set_chip_and_handler
  ARM: kprobes: make more tests conditional

 arch/arm/Kconfig.debug             |    1 +
 arch/arm/kernel/arch_timer.c       |    2 ++
 arch/arm/kernel/irq.c              |    2 ++
 arch/arm/kernel/kprobes-test-arm.c |    4 +++-
 kernel/irq/chip.c                  |    2 ++
 5 files changed, 10 insertions(+), 1 deletion(-)

-- 
1.7.10

The mls instruction is not available in ARMv6K or below, so we
should make the test conditional on at least ARMv7. ldrex/strex
are available in ARMv6K or ARMv7, which we can test by checking
the CONFIG_CPU_32v6K symbol. Just testing for ARMv6 is not enough.

/tmp/ccuMTZ8D.s: Assembler messages:
/tmp/ccuMTZ8D.s:22188: Error: selected processor does not support ARM mode `mls r0,r1,r2,r3'
/tmp/ccuMTZ8D.s:22222: Error: selected processor does not support ARM mode `mlshi r7,r8,r9,r10'
/tmp/ccuMTZ8D.s:22252: Error: selected processor does not support ARM mode `mls lr,r1,r2,r13'

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Jon Medhurst <redacted>
Cc: Russell King <redacted>
Cc: Nicolas Pitre <redacted>
Cc: Leif Lindholm <redacted>
---
 arch/arm/kernel/kprobes-test-arm.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/arm/kernel/kprobes-test-arm.c b/arch/arm/kernel/kprobes-test-arm.c
index 38c1a3b..3e87ff7 100644
--- a/arch/arm/kernel/kprobes-test-arm.c
+++ b/arch/arm/kernel/kprobes-test-arm.c

@@ -367,9 +367,11 @@ void kprobe_arm_test_cases(void)
 	TEST_UNSUPPORTED(".word 0xe0500090 @ undef")
 	TEST_UNSUPPORTED(".word 0xe05fff9f @ undef")
 
+#if __LINUX_ARM_ARCH__ >= 7
 	TEST_RRR(  "mls		r0, r",1, VAL1,", r",2, VAL2,", r",3,  VAL3,"")
 	TEST_RRR(  "mlshi	r7, r",8, VAL3,", r",9, VAL1,", r",10, VAL2,"")
 	TEST_RR(   "mls		lr, r",1, VAL2,", r",2, VAL3,", r13")
+#endif
 	TEST_UNSUPPORTED(".word 0xe06f3291 @ mls pc, r1, r2, r3")
 	TEST_UNSUPPORTED(".word 0xe060329f @ mls r0, pc, r2, r3")
 	TEST_UNSUPPORTED(".word 0xe0603f91 @ mls r0, r1, pc, r3")

@@ -454,7 +456,7 @@ void kprobe_arm_test_cases(void)
 	TEST_UNSUPPORTED(".word	0xe1500090") /* Unallocated space */
 	TEST_UNSUPPORTED(".word	0xe1600090") /* Unallocated space */
 	TEST_UNSUPPORTED(".word	0xe1700090") /* Unallocated space */
-#if __LINUX_ARM_ARCH__ >= 6
+#ifdef CONFIG_CPU_32v6K
 	TEST_UNSUPPORTED("ldrex	r2, [sp]")
 	TEST_UNSUPPORTED("strexd	r0, r2, r3, [sp]")
 	TEST_UNSUPPORTED("ldrexd	r2, r3, [sp]")

-- 
1.7.10

When ARMv6 is enabled, we build the kernel with -march=armv6 or
-march=armv6k, which means the bfi instruction is not available.
Instead, it only works with -march=armv6t2 or -march=armv7-a.

Without this patch, building rand-enIHAOL results in:

/tmp/ccwCsCXC.s: Assembler messages:
/tmp/ccwCsCXC.s:49: Error: selected processor does not support ARM mode `bfi r3,r2,#0,#8'

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Will Deacon <redacted>
Cc: Russell King <redacted>
---
 arch/arm/Kconfig.debug |    1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug
index f15f82b..11b9ff4 100644
--- a/arch/arm/Kconfig.debug
+++ b/arch/arm/Kconfig.debug

@@ -398,6 +398,7 @@ config ARM_KPROBES_TEST
 config PID_IN_CONTEXTIDR
 	bool "Write the current PID to the CONTEXTIDR register"
 	depends on CPU_COPY_V6
+	depends on CPU_V7 && !CPU_V6
 	help
 	  Enabling this option causes the kernel to write the current PID to
 	  the PROCID field of the CONTEXTIDR register, at the expense of some

-- 
1.7.10

The recently added Emma Mobile GPIO driver calls set_irq_flags
and irq_set_chip_and_handler for the interrupts it exports and
it can be built as a module, which currently fails with

ERROR: "set_irq_flags" [drivers/gpio/gpio-em.ko] undefined!
ERROR: "irq_set_chip_and_handler_name" [drivers/gpio/gpio-em.ko] undefined!

We either need to replace the call to set_irq_flags with something
else or export that function. This patch does the latter.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Magnus Damm <redacted>
Cc: Linus Walleij <redacted>
Cc: Rafael J. Wysocki <redacted>
Cc: Thomas Gleixner <redacted>
Cc: Russell King <redacted>
---
 arch/arm/kernel/irq.c |    2 ++
 kernel/irq/chip.c     |    2 ++
 2 files changed, 4 insertions(+)

diff --git a/arch/arm/kernel/irq.c b/arch/arm/kernel/irq.c
index 16cedb4..8961650 100644
--- a/arch/arm/kernel/irq.c
+++ b/arch/arm/kernel/irq.c

@@ -34,6 +34,7 @@
 #include <linux/list.h>
 #include <linux/kallsyms.h>
 #include <linux/proc_fs.h>
+#include <linux/export.h>
 
 #include <asm/exception.h>
 #include <asm/mach/arch.h>

@@ -109,6 +110,7 @@ void set_irq_flags(unsigned int irq, unsigned int iflags)
 	/* Order is clear bits in "clr" then set bits in "set" */
 	irq_modify_status(irq, clr, set & ~clr);
 }
+EXPORT_SYMBOL_GPL(set_irq_flags);
 
 void __init init_IRQ(void)
 {

diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index eebd6d5..3c3cea3 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c

@@ -13,6 +13,7 @@
 #include <linux/irq.h>
 #include <linux/msi.h>
 #include <linux/module.h>
+#include <linux/export.h>
 #include <linux/interrupt.h>
 #include <linux/kernel_stat.h>
 

@@ -671,6 +672,7 @@ irq_set_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
 	irq_set_chip(irq, chip);
 	__irq_set_handler(irq, handle, 0, name);
 }
+EXPORT_SYMBOL_GPL(irq_set_chip_and_handler_name);
 
 void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set)
 {

-- 
1.7.10

read_current_timer is used in the get_cycles() function when
ARM_ARCH_TIMER is set, and that function can be inlined into
driver modules, so we should export the function to avoid
errors like

ERROR: "read_current_timer" [drivers/video/udlfb.ko] undefined!
ERROR: "read_current_timer" [crypto/tcrypt.ko] undefined!

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Shinya Kuribayashi <redacted>
Cc: Stephen Boyd <redacted>
Cc: Will Deacon <redacted>
Cc: Russell King <redacted>
---
 arch/arm/kernel/arch_timer.c |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm/kernel/arch_timer.c b/arch/arm/kernel/arch_timer.c
index cf25880..6327d1f 100644
--- a/arch/arm/kernel/arch_timer.c
+++ b/arch/arm/kernel/arch_timer.c

@@ -14,6 +14,7 @@
 #include <linux/device.h>
 #include <linux/smp.h>
 #include <linux/cpu.h>
+#include <linux/export.h>
 #include <linux/jiffies.h>
 #include <linux/clockchips.h>
 #include <linux/interrupt.h>

@@ -232,6 +233,7 @@ int read_current_timer(unsigned long *timer_val)
 	*timer_val = arch_counter_get_cntpct();
 	return 0;
 }
+EXPORT_SYMBOL_GPL(read_current_timer);
 
 static struct clocksource clocksource_counter = {
 	.name	= "arch_sys_counter",

-- 
1.7.10

Hi Arnd,

On Wed, Aug 22, 2012 at 03:29:38PM +0100, Arnd Bergmann wrote:

Nah, I'll fix the contextidr_notifier instead. I forgot that this stuff gets
used on non-SMP v6 platforms.

Cheers,

Will

On Wed, 22 Aug 2012, Arnd Bergmann wrote:

The mls instruction is not available in ARMv6K or below, so we
should make the test conditional on at least ARMv7. ldrex/strex
are available in ARMv6K or ARMv7, which we can test by checking
the CONFIG_CPU_32v6K symbol. Just testing for ARMv6 is not enough.

The ldrex/strex instructions are available on ARMv6.  It's only the d 
variants (strexd/ldrexd) which are only available from ARMv6k.


Nicolas

On Wednesday 22 August 2012, Will Deacon wrote:

quoted

@@ -398,6 +398,7 @@ config ARM_KPROBES_TEST
 config PID_IN_CONTEXTIDR
      bool "Write the current PID to the CONTEXTIDR register"
      depends on CPU_COPY_V6
+     depends on CPU_V7 && !CPU_V6
      help
        Enabling this option causes the kernel to write the current PID to
        the PROCID field of the CONTEXTIDR register, at the expense of some

Nah, I'll fix the contextidr_notifier instead. I forgot that this stuff gets
used on non-SMP v6 platforms.

Ok, thanks!

	Arnd

On Wednesday 22 August 2012, Nicolas Pitre wrote:

On Wed, 22 Aug 2012, Arnd Bergmann wrote:

quoted

The mls instruction is not available in ARMv6K or below, so we
should make the test conditional on at least ARMv7. ldrex/strex
are available in ARMv6K or ARMv7, which we can test by checking
the CONFIG_CPU_32v6K symbol. Just testing for ARMv6 is not enough.

The ldrex/strex instructions are available on ARMv6.  It's only the d 
variants (strexd/ldrexd) which are only available from ARMv6k.

Ok. How is the version below then? I haven't tested this one yet.

	Arnd

8<---

From d878ab212cf0ac1957be83ad80dc734ace2b476c Mon Sep 17 00:00:00 2001

From: Arnd Bergmann <arnd@arndb.de>
Date: Thu, 16 Aug 2012 07:49:31 +0000
Subject: [PATCH] ARM: kprobes: make more tests conditional

The mls instruction is not available in ARMv6K or below, so we
should make the test conditional on at least ARMv7. ldrexd/strexd
are available in ARMv6K or ARMv7, which we can test by checking
the CONFIG_CPU_32v6K symbol. Just testing for ARMv6 is not enough.

/tmp/ccuMTZ8D.s: Assembler messages:
/tmp/ccuMTZ8D.s:22188: Error: selected processor does not support ARM mode `mls r0,r1,r2,r3'
/tmp/ccuMTZ8D.s:22222: Error: selected processor does not support ARM mode `mlshi r7,r8,r9,r10'
/tmp/ccuMTZ8D.s:22252: Error: selected processor does not support ARM mode `mls lr,r1,r2,r13'

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Jon Medhurst <redacted>
Cc: Russell King <redacted>
Cc: Nicolas Pitre <redacted>
Cc: Leif Lindholm <redacted>
---
 arch/arm/kernel/kprobes-test-arm.c |    4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/arm/kernel/kprobes-test-arm.c b/arch/arm/kernel/kprobes-test-arm.c
index 38c1a3b..fc9f6e0 100644
--- a/arch/arm/kernel/kprobes-test-arm.c
+++ b/arch/arm/kernel/kprobes-test-arm.c

@@ -367,9 +367,11 @@ void kprobe_arm_test_cases(void)
 	TEST_UNSUPPORTED(".word 0xe0500090 @ undef")
 	TEST_UNSUPPORTED(".word 0xe05fff9f @ undef")
 
+#if __LINUX_ARM_ARCH__ >= 7
 	TEST_RRR(  "mls		r0, r",1, VAL1,", r",2, VAL2,", r",3,  VAL3,"")
 	TEST_RRR(  "mlshi	r7, r",8, VAL3,", r",9, VAL1,", r",10, VAL2,"")
 	TEST_RR(   "mls		lr, r",1, VAL2,", r",2, VAL3,", r13")
+#endif
 	TEST_UNSUPPORTED(".word 0xe06f3291 @ mls pc, r1, r2, r3")
 	TEST_UNSUPPORTED(".word 0xe060329f @ mls r0, pc, r2, r3")
 	TEST_UNSUPPORTED(".word 0xe0603f91 @ mls r0, r1, pc, r3")

@@ -456,8 +458,10 @@ void kprobe_arm_test_cases(void)
 	TEST_UNSUPPORTED(".word	0xe1700090") /* Unallocated space */
 #if __LINUX_ARM_ARCH__ >= 6
 	TEST_UNSUPPORTED("ldrex	r2, [sp]")
+#ifdef CONFIG_CPU_32v6K
 	TEST_UNSUPPORTED("strexd	r0, r2, r3, [sp]")
 	TEST_UNSUPPORTED("ldrexd	r2, r3, [sp]")
+#endif
 	TEST_UNSUPPORTED("strexb	r0, r2, [sp]")
 	TEST_UNSUPPORTED("ldrexb	r2, [sp]")
 	TEST_UNSUPPORTED("strexh	r0, r2, [sp]")

-- 
1.7.10

On Wed, 22 Aug 2012, Arnd Bergmann wrote:

On Wednesday 22 August 2012, Nicolas Pitre wrote:

quoted

On Wed, 22 Aug 2012, Arnd Bergmann wrote:

quoted

The mls instruction is not available in ARMv6K or below, so we
should make the test conditional on at least ARMv7. ldrex/strex
are available in ARMv6K or ARMv7, which we can test by checking
the CONFIG_CPU_32v6K symbol. Just testing for ARMv6 is not enough.

The ldrex/strex instructions are available on ARMv6.  It's only the d 
variants (strexd/ldrexd) which are only available from ARMv6k.

Ok. How is the version below then? I haven't tested this one yet.

In fact, I think the b variants are ARMv6k+ as well.  Only the plain 
(non b non d) variants are available on ARMv6.

On 08/22/12 07:29, Arnd Bergmann wrote:

read_current_timer is used in the get_cycles() function when
ARM_ARCH_TIMER is set, and that function can be inlined into
driver modules, so we should export the function to avoid
errors like

ERROR: "read_current_timer" [drivers/video/udlfb.ko] undefined!
ERROR: "read_current_timer" [crypto/tcrypt.ko] undefined!

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Shinya Kuribayashi <redacted>

Acked-by: Stephen Boyd <redacted>

I ran into this last week but forgot to send the patch. Thanks.

-- 
Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.

On Wed, Aug 22, 2012 at 06:15:14PM +0100, Stephen Boyd wrote:

On 08/22/12 07:29, Arnd Bergmann wrote:

quoted

read_current_timer is used in the get_cycles() function when
ARM_ARCH_TIMER is set, and that function can be inlined into
driver modules, so we should export the function to avoid
errors like

ERROR: "read_current_timer" [drivers/video/udlfb.ko] undefined!
ERROR: "read_current_timer" [crypto/tcrypt.ko] undefined!

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Shinya Kuribayashi <redacted>

Acked-by: Stephen Boyd <redacted>

I ran into this last week but forgot to send the patch. Thanks.

Looks good to me, thanks Arnd:

Acked-by: Will Deacon <redacted>

On the topic of the timer stuff: Shinya/Stephen, did you have a chance to
look at the registration stuff that was proposed? I'm happy to push it if
people will actually use it.

Cheers,

Will

On 08/22/12 10:49, Will Deacon wrote:

On the topic of the timer stuff: Shinya/Stephen, did you have a chance to
look at the registration stuff that was proposed? I'm happy to push it if
people will actually use it.

Yes I have tested it on our internal trees and it looks good. I plan to
send a patch to move MSM's timers over to it later this week so that we
have at least two users upstream.

-- 
Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.

On Wed, Aug 22, 2012 at 06:57:20PM +0100, Stephen Boyd wrote:

On 08/22/12 10:49, Will Deacon wrote:

quoted

On the topic of the timer stuff: Shinya/Stephen, did you have a chance to
look at the registration stuff that was proposed? I'm happy to push it if
people will actually use it.

Yes I have tested it on our internal trees and it looks good. I plan to
send a patch to move MSM's timers over to it later this week so that we
have at least two users upstream.

Awesome, I'll dust that series off at -rc3 then.

Will

On Wednesday 22 August 2012, Nicolas Pitre wrote:

On Wed, 22 Aug 2012, Arnd Bergmann wrote:

quoted

quoted

The ldrex/strex instructions are available on ARMv6.  It's only the d 
variants (strexd/ldrexd) which are only available from ARMv6k.

Ok. How is the version below then? I haven't tested this one yet.

In fact, I think the b variants are ARMv6k+ as well.  Only the plain 
(non b non d) variants are available on ARMv6.

Ok, third attempt then. This leaves ldrex for ARMv6 but marks
{st,ld}rex{b,h,d} as V6K specific (which includes ARMv7).

	Arnd

8<-----

From 6eab418c61c18393006f30d189e2f28d6e403040 Mon Sep 17 00:00:00 2001

From: Arnd Bergmann <arnd@arndb.de>
Date: Thu, 16 Aug 2012 07:49:31 +0000
Subject: [PATCH] ARM: kprobes: make more tests conditional

The mls instruction is not available in ARMv6K or below, so we
should make the test conditional on at least ARMv7. ldrexd/strexd
are available in ARMv6K or ARMv7, which we can test by checking
the CONFIG_CPU_32v6K symbol. Just testing for ARMv6 is not enough.

/tmp/ccuMTZ8D.s: Assembler messages:
/tmp/ccuMTZ8D.s:22188: Error: selected processor does not support ARM mode `mls r0,r1,r2,r3'
/tmp/ccuMTZ8D.s:22222: Error: selected processor does not support ARM mode `mlshi r7,r8,r9,r10'
/tmp/ccuMTZ8D.s:22252: Error: selected processor does not support ARM mode `mls lr,r1,r2,r13'

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Jon Medhurst <redacted>
Cc: Russell King <redacted>
Cc: Nicolas Pitre <redacted>
Cc: Leif Lindholm <redacted>
---
 arch/arm/kernel/kprobes-test-arm.c |    4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/arm/kernel/kprobes-test-arm.c b/arch/arm/kernel/kprobes-test-arm.c
index 38c1a3b..58dd6c3 100644
--- a/arch/arm/kernel/kprobes-test-arm.c
+++ b/arch/arm/kernel/kprobes-test-arm.c

@@ -367,9 +367,11 @@ void kprobe_arm_test_cases(void)
 	TEST_UNSUPPORTED(".word 0xe0500090 @ undef")
 	TEST_UNSUPPORTED(".word 0xe05fff9f @ undef")
 
+#if __LINUX_ARM_ARCH__ >= 7
 	TEST_RRR(  "mls		r0, r",1, VAL1,", r",2, VAL2,", r",3,  VAL3,"")
 	TEST_RRR(  "mlshi	r7, r",8, VAL3,", r",9, VAL1,", r",10, VAL2,"")
 	TEST_RR(   "mls		lr, r",1, VAL2,", r",2, VAL3,", r13")
+#endif
 	TEST_UNSUPPORTED(".word 0xe06f3291 @ mls pc, r1, r2, r3")
 	TEST_UNSUPPORTED(".word 0xe060329f @ mls r0, pc, r2, r3")
 	TEST_UNSUPPORTED(".word 0xe0603f91 @ mls r0, r1, pc, r3")

@@ -456,6 +458,7 @@ void kprobe_arm_test_cases(void)
 	TEST_UNSUPPORTED(".word	0xe1700090") /* Unallocated space */
 #if __LINUX_ARM_ARCH__ >= 6
 	TEST_UNSUPPORTED("ldrex	r2, [sp]")
+#ifdef CONFIG_CPU_32v6K
 	TEST_UNSUPPORTED("strexd	r0, r2, r3, [sp]")
 	TEST_UNSUPPORTED("ldrexd	r2, r3, [sp]")
 	TEST_UNSUPPORTED("strexb	r0, r2, [sp]")

@@ -463,6 +466,7 @@ void kprobe_arm_test_cases(void)
 	TEST_UNSUPPORTED("strexh	r0, r2, [sp]")
 	TEST_UNSUPPORTED("ldrexh	r2, [sp]")
 #endif
+#endif
 	TEST_GROUP("Extra load/store instructions")
 
 	TEST_RPR(  "strh	r",0, VAL1,", [r",1, 48,", -r",2, 24,"]")

-- 
1.7.10

On Wed, 22 Aug 2012, Arnd Bergmann wrote:

On Wednesday 22 August 2012, Nicolas Pitre wrote:

quoted

On Wed, 22 Aug 2012, Arnd Bergmann wrote:

quoted

quoted

The ldrex/strex instructions are available on ARMv6.  It's only the d 
variants (strexd/ldrexd) which are only available from ARMv6k.

Ok. How is the version below then? I haven't tested this one yet.

In fact, I think the b variants are ARMv6k+ as well.  Only the plain 
(non b non d) variants are available on ARMv6.

Ok, third attempt then. This leaves ldrex for ARMv6 but marks
{st,ld}rex{b,h,d} as V6K specific (which includes ARMv7).

	Arnd

8<-----
From 6eab418c61c18393006f30d189e2f28d6e403040 Mon Sep 17 00:00:00 2001
From: Arnd Bergmann <arnd@arndb.de>
Date: Thu, 16 Aug 2012 07:49:31 +0000
Subject: [PATCH] ARM: kprobes: make more tests conditional

The mls instruction is not available in ARMv6K or below, so we
should make the test conditional on at least ARMv7. ldrexd/strexd
are available in ARMv6K or ARMv7, which we can test by checking
the CONFIG_CPU_32v6K symbol. Just testing for ARMv6 is not enough.

/tmp/ccuMTZ8D.s: Assembler messages:
/tmp/ccuMTZ8D.s:22188: Error: selected processor does not support ARM mode `mls r0,r1,r2,r3'
/tmp/ccuMTZ8D.s:22222: Error: selected processor does not support ARM mode `mlshi r7,r8,r9,r10'
/tmp/ccuMTZ8D.s:22252: Error: selected processor does not support ARM mode `mls lr,r1,r2,r13'

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Jon Medhurst <redacted>
Cc: Russell King <redacted>
Cc: Nicolas Pitre <redacted>
Cc: Leif Lindholm <redacted>

Acked-by: Nicolas Pitre <redacted>

On Wed, 2012-08-22 at 18:41 +0000, Arnd Bergmann wrote:

On Wednesday 22 August 2012, Nicolas Pitre wrote:

quoted

On Wed, 22 Aug 2012, Arnd Bergmann wrote:

quoted

quoted

The ldrex/strex instructions are available on ARMv6.  It's only the d 
variants (strexd/ldrexd) which are only available from ARMv6k.

Ok. How is the version below then? I haven't tested this one yet.

In fact, I think the b variants are ARMv6k+ as well.  Only the plain 
(non b non d) variants are available on ARMv6.

Ok, third attempt then. This leaves ldrex for ARMv6 but marks
{st,ld}rex{b,h,d} as V6K specific (which includes ARMv7).

ARMv7 does set CPU_32v6K, because arch/arm/mm/Kconfig has

config CPU_V7
	bool "Support ARM V7 processor" if ARCH_INTEGRATOR || MACH_REALVIEW_EB || MACH_REALVIEW_PBX
	select CPU_32v6K
	select CPU_32v7

but this seems more for peripheral reasons not because all the various
CPU configs systematically select the earlier architecture variants,
e.g. CPU_V7 doesn't select CPU_32v6.

So I would have been inclined to test for

#if defined(CONFIG_CPU_32v6K) || (__LINUX_ARM_ARCH__ >= 7) 

but as the current patch is functionally correct I'm not going to
suggest a v4 patch :-)

If you do feel so inclined for a v4 however ;-) you could also make the
mls part of the patch tidier by moving the added #endif to instead
terminate the preceding "#if __LINUX_ARM_ARCH__ >= 6", i.e.

@@ -367,8 +367,10 @@ void kprobe_arm_test_cases(void)
 	TEST_UNSUPPORTED(".word 0xe0500090 @ undef")
 	TEST_UNSUPPORTED(".word 0xe05fff9f @ undef")
+#endif
 
+#if __LINUX_ARM_ARCH__ >= 7
 	TEST_RRR(  "mls		r0, r",1, VAL1,", r",2, VAL2,", r",3,  VAL3,"")
 	TEST_RRR(  "mlshi	r7, r",8, VAL3,", r",9, VAL1,", r",10, VAL2,"")
 	TEST_RR(   "mls		lr, r",1, VAL2,", r",2, VAL3,", r13")

this looks funny in patch form, but the resulting source file is more
consistent with other conditional tests.

On 8/23/2012 2:49 AM, Will Deacon wrote:

On Wed, Aug 22, 2012 at 06:15:14PM +0100, Stephen Boyd wrote:

quoted

On 08/22/12 07:29, Arnd Bergmann wrote:

quoted

read_current_timer is used in the get_cycles() function when
ARM_ARCH_TIMER is set, and that function can be inlined into
driver modules, so we should export the function to avoid
errors like

ERROR: "read_current_timer" [drivers/video/udlfb.ko] undefined!
ERROR: "read_current_timer" [crypto/tcrypt.ko] undefined!

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Shinya Kuribayashi <redacted>

Acked-by: Stephen Boyd <redacted>

I ran into this last week but forgot to send the patch. Thanks.

Looks good to me, thanks Arnd:

Acked-by: Will Deacon <redacted>

I haven't hit with this so far with our configs though, but why not?

Acked-by: Shinya Kuribayashi <redacted>

On 8/23/2012 2:58 AM, Will Deacon wrote:

On Wed, Aug 22, 2012 at 06:57:20PM +0100, Stephen Boyd wrote:

quoted

On 08/22/12 10:49, Will Deacon wrote:

quoted

On the topic of the timer stuff: Shinya/Stephen, did you have a chance to
look at the registration stuff that was proposed? I'm happy to push it if
people will actually use it.

Yes I have tested it on our internal trees and it looks good. I plan to
send a patch to move MSM's timers over to it later this week so that we
have at least two users upstream.

And I think other A9 MPcore platforms, namely OMAP and EXYNOS, would
also be candidates, who tried to skip calibrate_delay() in the past
(OMAP) or currently provide non-smp_twd timers as localtimers (EXYNOS).
I may miss the latest status of those BSPs, but believe that we would
have more users (>2) in the future.

Awesome, I'll dust that series off at -rc3 then.

It works for me for weeks without troubles, looking forward to it.
--
Shinya Kuribayashi
Renesas Electronics

On Wednesday 22 August 2012, Tixy wrote:

Ok, here we go.

	Arnd


commit abfef4db8731591fbb721262bd4712662aaa6d14
Author: Arnd Bergmann [off-list ref]
Date:   Thu Aug 16 07:49:31 2012 +0000

    ARM: kprobes: make more tests conditional
    
    The mls instruction is not available in ARMv6K or below, so we
    should make the test conditional on at least ARMv7. ldrexd/strexd
    are available in ARMv6K or ARMv7, which we can test by checking
    the CONFIG_CPU_32v6K symbol.
    
    /tmp/ccuMTZ8D.s: Assembler messages:
    /tmp/ccuMTZ8D.s:22188: Error: selected processor does not support ARM mode `mls r0,r1,r2,r3'
    /tmp/ccuMTZ8D.s:22222: Error: selected processor does not support ARM mode `mlshi r7,r8,r9,r10'
    /tmp/ccuMTZ8D.s:22252: Error: selected processor does not support ARM mode `mls lr,r1,r2,r13'
    
    Signed-off-by: Arnd Bergmann [off-list ref]
    Cc: Jon Medhurst [off-list ref]
    Cc: Russell King [off-list ref]
    Cc: Nicolas Pitre [off-list ref]
    Cc: Leif Lindholm [off-list ref]

diff --git a/arch/arm/kernel/kprobes-test-arm.c b/arch/arm/kernel/kprobes-test-arm.c
index 38c1a3b..8393129 100644
--- a/arch/arm/kernel/kprobes-test-arm.c
+++ b/arch/arm/kernel/kprobes-test-arm.c

@@ -366,7 +366,9 @@ void kprobe_arm_test_cases(void)
 	TEST_UNSUPPORTED(".word 0xe04f0392 @ umaal r0, pc, r2, r3")
 	TEST_UNSUPPORTED(".word 0xe0500090 @ undef")
 	TEST_UNSUPPORTED(".word 0xe05fff9f @ undef")
+#endif
 
+#if __LINUX_ARM_ARCH__ >= 7
 	TEST_RRR(  "mls		r0, r",1, VAL1,", r",2, VAL2,", r",3,  VAL3,"")
 	TEST_RRR(  "mlshi	r7, r",8, VAL3,", r",9, VAL1,", r",10, VAL2,"")
 	TEST_RR(   "mls		lr, r",1, VAL2,", r",2, VAL3,", r13")

@@ -456,6 +458,8 @@ void kprobe_arm_test_cases(void)
 	TEST_UNSUPPORTED(".word	0xe1700090") /* Unallocated space */
 #if __LINUX_ARM_ARCH__ >= 6
 	TEST_UNSUPPORTED("ldrex	r2, [sp]")
+#endif
+#if (__LINUX_ARM_ARCH__ >= 7) || defined(CONFIG_CPU_32v6K)
 	TEST_UNSUPPORTED("strexd	r0, r2, r3, [sp]")
 	TEST_UNSUPPORTED("ldrexd	r2, r3, [sp]")
 	TEST_UNSUPPORTED("strexb	r0, r2, [sp]")

On Thu, Aug 23, 2012 at 12:51:01AM +0100, Tixy wrote:

On Wed, 2012-08-22 at 18:41 +0000, Arnd Bergmann wrote:

quoted

On Wednesday 22 August 2012, Nicolas Pitre wrote:

quoted

On Wed, 22 Aug 2012, Arnd Bergmann wrote:

quoted

quoted

The ldrex/strex instructions are available on ARMv6.  It's only the d 
variants (strexd/ldrexd) which are only available from ARMv6k.

Ok. How is the version below then? I haven't tested this one yet.

In fact, I think the b variants are ARMv6k+ as well.  Only the plain 
(non b non d) variants are available on ARMv6.

Ok, third attempt then. This leaves ldrex for ARMv6 but marks
{st,ld}rex{b,h,d} as V6K specific (which includes ARMv7).

ARMv7 does set CPU_32v6K, because arch/arm/mm/Kconfig has

config CPU_V7
	bool "Support ARM V7 processor" if ARCH_INTEGRATOR || MACH_REALVIEW_EB || MACH_REALVIEW_PBX
	select CPU_32v6K
	select CPU_32v7

but this seems more for peripheral reasons not because all the various
CPU configs systematically select the earlier architecture variants,
e.g. CPU_V7 doesn't select CPU_32v6.

So I would have been inclined to test for

#if defined(CONFIG_CPU_32v6K) || (__LINUX_ARM_ARCH__ >= 7) 

FWIW, the selection of the optimised atomic64 implementation for ARM (which
uses the double-word exclusive instructions) boils down to CONFIG_CPU_32v6K,
so I think the additional __LINUX_ARM_ARCH__ check is probably overkill.

Will

On Thu, 2012-08-23 at 12:09 +0000, Arnd Bergmann wrote:

commit abfef4db8731591fbb721262bd4712662aaa6d14
Author: Arnd Bergmann [off-list ref]
Date:   Thu Aug 16 07:49:31 2012 +0000

    ARM: kprobes: make more tests conditional
    
    The mls instruction is not available in ARMv6K or below, so we
    should make the test conditional on at least ARMv7. ldrexd/strexd
    are available in ARMv6K or ARMv7, which we can test by checking
    the CONFIG_CPU_32v6K symbol.
    
    /tmp/ccuMTZ8D.s: Assembler messages:
    /tmp/ccuMTZ8D.s:22188: Error: selected processor does not support ARM mode `mls r0,r1,r2,r3'
    /tmp/ccuMTZ8D.s:22222: Error: selected processor does not support ARM mode `mlshi r7,r8,r9,r10'
    /tmp/ccuMTZ8D.s:22252: Error: selected processor does not support ARM mode `mls lr,r1,r2,r13'
    
    Signed-off-by: Arnd Bergmann [off-list ref]
    Cc: Jon Medhurst [off-list ref]
    Cc: Russell King [off-list ref]
    Cc: Nicolas Pitre [off-list ref]
    Cc: Leif Lindholm [off-list ref]

Thanks for your indulgence :-) With the white-space damage fixed...

Acked-by: Jon Medhurst <redacted>

I test built this for v6, v6k and v7 before and after applying the patch
to verify if behaves as expected, so you can add my Tested-by if you
want.

I also tried a v4 platform (forgot we supported those) and there will be
a patch coming to fix that...

On Thu, 23 Aug 2012, Arnd Bergmann wrote:

On Wednesday 22 August 2012, Tixy wrote:

quoted

If you do feel so inclined for a v4 however ;-) you could also make the
mls part of the patch tidier by moving the added #endif to instead
terminate the preceding "#if __LINUX_ARM_ARCH__ >= 6", i.e.

@@ -367,8 +367,10 @@ void kprobe_arm_test_cases(void)
 	TEST_UNSUPPORTED(".word 0xe0500090 @ undef")
 	TEST_UNSUPPORTED(".word 0xe05fff9f @ undef")
+#endif
 
+#if __LINUX_ARM_ARCH__ >= 7
 	TEST_RRR(  "mls		r0, r",1, VAL1,", r",2, VAL2,", r",3,  VAL3,"")
 	TEST_RRR(  "mlshi	r7, r",8, VAL3,", r",9, VAL1,", r",10, VAL2,"")
 	TEST_RR(   "mls		lr, r",1, VAL2,", r",2, VAL3,", r13")

this looks funny in patch form, but the resulting source file is more
consistent with other conditional tests.

Ok, here we go.

	Arnd


commit abfef4db8731591fbb721262bd4712662aaa6d14
Author: Arnd Bergmann [off-list ref]
Date:   Thu Aug 16 07:49:31 2012 +0000

    ARM: kprobes: make more tests conditional
    
    The mls instruction is not available in ARMv6K or below, so we
    should make the test conditional on at least ARMv7. ldrexd/strexd
    are available in ARMv6K or ARMv7, which we can test by checking
    the CONFIG_CPU_32v6K symbol.
    
    /tmp/ccuMTZ8D.s: Assembler messages:
    /tmp/ccuMTZ8D.s:22188: Error: selected processor does not support ARM mode `mls r0,r1,r2,r3'
    /tmp/ccuMTZ8D.s:22222: Error: selected processor does not support ARM mode `mlshi r7,r8,r9,r10'
    /tmp/ccuMTZ8D.s:22252: Error: selected processor does not support ARM mode `mls lr,r1,r2,r13'
    
    Signed-off-by: Arnd Bergmann [off-list ref]
    Cc: Jon Medhurst [off-list ref]
    Cc: Russell King [off-list ref]
    Cc: Nicolas Pitre [off-list ref]
    Cc: Leif Lindholm [off-list ref]

Acked-by: Nicolas Pitre <redacted>