From: <arnd@arndb.de>
Hi Russell,
Here are some patches that belong into your domain, I hope you can
just send the lot to Linus the next time you send other patches.
These bug fixes all address problems found with automated build testing.
Some of them have been around for a long time, other bugs are
regressions since the merge window.
Arnd
The following changes since commit 0e51793e162ca432fc5f04178cf82b80a92c2659:
Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm (2012-10-07 21:20:57 +0900)
are available in the git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc.git tags/fixes-for-rmk
for you to fetch changes up to 93c6cee8e966ceb78a08e6a69a3afc948b74d254:
ARM: warnings in arch/arm/include/asm/uaccess.h (2012-10-09 17:07:44 +0200)
----------------------------------------------------------------
Arnd Bergmann (9):
ARM: kprobes: make more tests conditional
ARM: export set_irq_flags
ARM: Fix another build warning in arch/arm/mm/alignment.c
ARM: export default read_current_timer
ARM: Xen: fix initial build problems:
ARM: pass -marm to gcc by default for both C and assembler
ARM: be really quiet when building with 'make -s'
ARM: binfmt_flat: unused variable 'persistent'
ARM: warnings in arch/arm/include/asm/uaccess.h
arch/arm/Kconfig | 1 +
arch/arm/Makefile | 13 +++++++------
arch/arm/boot/Makefile | 10 +++++-----
arch/arm/include/asm/flat.h | 2 +-
arch/arm/include/asm/uaccess.h | 4 ++--
arch/arm/kernel/irq.c | 2 ++
arch/arm/kernel/kprobes-test-arm.c | 4 ++++
arch/arm/lib/delay.c | 1 +
arch/arm/mm/alignment.c | 4 +++-
arch/arm/tools/Makefile | 2 +-
drivers/xen/Kconfig | 2 ++
drivers/xen/sys-hypervisor.c | 1 +
12 files changed, 30 insertions(+), 16 deletions(-)
Cc: bryan.wu at canonical.com
Cc: catalin.marinas at arm.com
Cc: dave.martin at linaro.org
Cc: jeremy at goop.org
Cc: jonathan.austin at arm.com
Cc: konrad.wilk at oracle.com
Cc: leif.lindholm at arm.com
Cc: linus.walleij at linaro.org
Cc: damm at opensource.se
Cc: mmarek at suse.cz
Cc: rjw at sisk.pl
Cc: rmk+kernel at arm.linux.org.uk
Cc: stefano.stabellini at eu.citrix.com
Cc: sboyd at codeaurora.org
Cc: tglx at linutronix.de
Cc: will.deacon at arm.com
Cc: xen-devel at lists.xensource.com
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!
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 ++
1 file changed, 2 insertions(+)
@@ -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__initinit_IRQ(void){
The flat_get_addr_from_rp() macro does not use the 'persistent' argument
on ARM, causing a harmless compiler warning. A cast to void removes
that warning.
Without this patch, building at91x40_defconfig results in:
fs/binfmt_flat.c: In function 'load_flat_file':
fs/binfmt_flat.c:746:17: warning: unused variable 'persistent' [-Wunused-variable]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Greg Ungerer <redacted>
Cc: Russell King <redacted>
Cc: Bryan Wu <redacted>
---
arch/arm/include/asm/flat.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
Sometimes we want the kernel build process to only print messages
on errors, e.g. in automated build testing. This uses the "kecho"
macro that the build system provides to hide a few informational
messages. Nothing changes for a regular "make" or "make V=1".
Without this patch, building any ARM kernel results in:
Kernel: arch/arm/boot/Image is ready
Kernel: arch/arm/boot/zImage is ready
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Nicolas Pitre <redacted>
Cc: Russell King <redacted>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Michal Marek <redacted>
---
arch/arm/boot/Makefile | 10 +++++-----
arch/arm/tools/Makefile | 2 +-
2 files changed, 6 insertions(+), 6 deletions(-)
The Linaro cross toolchain and probably others nowadays default to
building in THUMB2 mode. When building a kernel for a CPU that does
not support THUMB2, the compiler complains about incorrect flags.
We can work around this by setting -marm for all non-T2 builds.
Without this patch, building assabet_defconfig results in:
usr/initramfs_data.S:1:0: warning: target CPU does not support THUMB instructions [enabled by default]
arch/arm/nwfpe/entry.S:1:0: warning: target CPU does not support THUMB instructions [enabled by default]
firmware/cis/PCMLM28.cis.gen.S:1:0: warning: target CPU does not support THUMB instructions [enabled by default]
(and many more)
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Nicolas Pitre <redacted>
Cc: Russell King <redacted>
Cc: Dave Martin <redacted>
---
arch/arm/Makefile | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
@@ -21,8 +21,6 @@ endifOBJCOPYFLAGS:=-Obinary-R.comment-SGZFLAGS:=-9#KBUILD_CFLAGS +=-pipe-# Explicitly specifiy 32-bit ARM ISA since toolchain default can be -mthumb:-KBUILD_CFLAGS+=$(callcc-option,-marm,)# Never generate .eh_frameKBUILD_CFLAGS+=$(callcc-option,-fno-dwarf2-cfi-asm)
@@ -105,17 +103,20 @@ endififeq ($(CONFIG_THUMB2_KERNEL),y)AFLAGS_AUTOIT:=$(callas-option,-Wa$(comma)-mimplicit-it=always,-Wa$(comma)-mauto-it)AFLAGS_NOWARN:=$(callas-option,-Wa$(comma)-mno-warn-deprecated,-Wa$(comma)-W)-CFLAGS_THUMB2:=-mthumb$(AFLAGS_AUTOIT)$(AFLAGS_NOWARN)-AFLAGS_THUMB2:=$(CFLAGS_THUMB2)-Wa$(comma)-mthumb+CFLAGS_ISA:=-mthumb$(AFLAGS_AUTOIT)$(AFLAGS_NOWARN)+AFLAGS_ISA:=$(CFLAGS_ISA)-Wa$(comma)-mthumb# Work around buggy relocation from gas if requested:ifeq ($(CONFIG_THUMB2_AVOID_R_ARM_THM_JUMP11),y)CFLAGS_MODULE+=-fno-optimize-sibling-callsendif+else+CFLAGS_ISA:=$(callcc-option,-marm,)+AFLAGS_ISA:=$(CFLAGS_ISA)endif# Need -Uarm for gcc < 3.x-KBUILD_CFLAGS+=$(CFLAGS_ABI)$(CFLAGS_THUMB2)$(arch-y)$(tune-y)$(callcc-option,-mshort-load-bytes,$(callcc-option,-malignment-traps,))-msoft-float-Uarm-KBUILD_AFLAGS+=$(CFLAGS_ABI)$(AFLAGS_THUMB2)$(arch-y)$(tune-y)-includeasm/unified.h-msoft-float+KBUILD_CFLAGS+=$(CFLAGS_ABI)$(CFLAGS_ISA)$(arch-y)$(tune-y)$(callcc-option,-mshort-load-bytes,$(callcc-option,-malignment-traps,))-msoft-float-Uarm+KBUILD_AFLAGS+=$(CFLAGS_ABI)$(AFLAGS_ISA)$(arch-y)$(tune-y)-includeasm/unified.h-msoft-floatCHECKFLAGS+=-D__arm__
* The XEN_BALLOON code requires the balloon infrastructure that is not
getting built on ARM.
* The tmem hypercall is not available on ARM
* ARMv6 does not support cmpxchg on 16-bit words that are used in the
* sys-hypervisor.c needs to include linux/err.h in order to use the
IS_ERR/PTR_ERR/ERR_PTR family of functions.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stefano Stabellini <redacted>
Cc: Konrad Rzeszutek Wilk <redacted>
Cc: Jeremy Fitzhardinge <redacted>
Cc: xen-devel at lists.xensource.com
---
arch/arm/Kconfig | 1 +
drivers/xen/Kconfig | 2 ++
drivers/xen/sys-hypervisor.c | 1 +
3 files changed, 4 insertions(+)
@@ -1846,6 +1846,7 @@ config XEN_DOM0configXENbool"Xen guest support on ARM (EXPERIMENTAL)"depends onEXPERIMENTAL&&ARM&&OF+depends on!CPU_V6helpSayYifyouwanttorunLinuxinaVirtualMachineonXenonARM.
One such warning was recently fixed in a761cebf "ARM: Fix build warning
in arch/arm/mm/alignment.c" but only for the thumb2 case, this fixes
the other half.
arch/arm/mm/alignment.c: In function 'do_alignment':
arch/arm/mm/alignment.c:327:15: error: 'offset.un' may be used uninitialized in this function
arch/arm/mm/alignment.c:748:21: note: 'offset.un' was declared here
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <redacted>
---
arch/arm/mm/alignment.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
On NOMMU ARM, the __addr_ok() and __range_ok() macros do not evaluate
their arguments, which may lead to harmless build warnings in some
code where the variables are not used otherwise. Adding a cast to void
gets rid of the warning and does not make any semantic changes.
Without this patch, building at91x40_defconfig results in:
fs/read_write.c: In function 'rw_copy_check_uvector':
fs/read_write.c:684:9: warning: unused variable 'buf' [-Wunused-variable]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Greg Ungerer <redacted>
Cc: Russell King <redacted>
---
arch/arm/include/asm/uaccess.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
read_current_timer is used by get_cycles since "ARM: 7538/1: delay:
add registration mechanism for delay timer sources", and get_cycles
can be used by device drivers in loadable modules, so it has to
be exported.
Without this patch, building imote2_defconfig fails with
ERROR: "read_current_timer" [crypto/tcrypt.ko] undefined!
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Boyd <redacted>
Cc: Jonathan Austin <redacted>
Cc: Will Deacon <redacted>
Cc: Russell King <redacted>
---
arch/arm/lib/delay.c | 1 +
1 file changed, 1 insertion(+)
@@ -45,6 +45,7 @@ int read_current_timer(unsigned long *timer_val)*timer_val=delay_timer->read_current_timer();return0;}+EXPORT_SYMBOL_GPL(read_current_timer);staticvoid__timer_delay(unsignedlongcycles){
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 <arnd@arndb.de>
Acked-by: Jon Medhurst <redacted>
Acked-by: Nicolas Pitre <redacted>
Cc: Russell King <redacted>
Cc: Leif Lindholm <redacted>
---
arch/arm/kernel/kprobes-test-arm.c | 4 ++++
1 file changed, 4 insertions(+)
@@ -1846,6 +1846,7 @@ config XEN_DOM0configXENbool"Xen guest support on ARM (EXPERIMENTAL)"depends onEXPERIMENTAL&&ARM&&OF+depends on!CPU_V6helpSayYifyouwanttorunLinuxinaVirtualMachineonXenonARM.
Thanks for the patch and sorry for the build breakage!
On Tue, 9 Oct 2012, Arnd Bergmann wrote:
quoted hunk
* The XEN_BALLOON code requires the balloon infrastructure that is not
getting built on ARM.
* The tmem hypercall is not available on ARM
* ARMv6 does not support cmpxchg on 16-bit words that are used in the
* sys-hypervisor.c needs to include linux/err.h in order to use the
IS_ERR/PTR_ERR/ERR_PTR family of functions.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stefano Stabellini <redacted>
Cc: Konrad Rzeszutek Wilk <redacted>
Cc: Jeremy Fitzhardinge <redacted>
Cc: xen-devel at lists.xensource.com
---
arch/arm/Kconfig | 1 +
drivers/xen/Kconfig | 2 ++
drivers/xen/sys-hypervisor.c | 1 +
3 files changed, 4 insertions(+)
@@ -1846,6 +1846,7 @@ config XEN_DOM0configXENbool"Xen guest support on ARM (EXPERIMENTAL)"depends onEXPERIMENTAL&&ARM&&OF+depends on!CPU_V6helpSayYifyouwanttorunLinuxinaVirtualMachineonXenonARM.
Considering that we rely on the virtualization extensions, this one can
be:
depends on CPU_V7
The rest looks fine. I can submit a second patch to change !CPU_V6 into
CPU_V7 later, if you prefer.
* The tmem hypercall is not available on ARM
* ARMv6 does not support cmpxchg on 16-bit words that are used in the
missing the end of this sentence?
Right, I meant to say
* ARMv6 does not support cmpxchg on 16-bit words that are used in the
Xen grant table code, so we must ensure that Xen support is only built
on ARMv7-only kernels not combined ARMv6/v7 kernels.
This should be fixed differently in the future.
Arnd
From: Jonathan Austin <hidden> Date: 2012-10-09 15:41:07
Hi Arnd,
On 09/10/12 16:22, Arnd Bergmann wrote:
read_current_timer is used by get_cycles since "ARM: 7538/1: delay:
add registration mechanism for delay timer sources", and get_cycles
can be used by device drivers in loadable modules, so it has to
be exported.
Without this patch, building imote2_defconfig fails with
ERROR: "read_current_timer" [crypto/tcrypt.ko] undefined!
@@ -45,6 +45,7 @@ int read_current_timer(unsigned long *timer_val)*timer_val=delay_timer->read_current_timer();return0;}+EXPORT_SYMBOL_GPL(read_current_timer);
Perhaps this fits better in armksyms.c? That way it lives with
arm_delay_ops and friends.
I've got a patch doing it like that, which I can put in Russell's
patch-system, unless you prefer doing it in delay.c for any reason?
Jonny
(Here's the original patch sent to the kernel-janitors list and Will Deacon)
-------8<---------
On ARM, get_cycles() is implemented in terms of read_current_timer(), but
the latter is not exported to modules, resulting in failure to link:
ERROR: "read_current_timer" [fs/ext4/ext4.ko] undefined!
This patch exports the symbol as required.
Reported-by: Fengguang Wu <redacted>
Acked-by: Will Deacon <redacted>
Signed-off-by: Jonathan Austin <redacted>
---
arch/arm/kernel/armksyms.c | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)
From: Russell King - ARM Linux <hidden> Date: 2012-10-09 16:06:15
On Tue, Oct 09, 2012 at 05:22:59PM +0200, Arnd Bergmann wrote:
* The XEN_BALLOON code requires the balloon infrastructure that is not
getting built on ARM.
* The tmem hypercall is not available on ARM
* ARMv6 does not support cmpxchg on 16-bit words that are used in the
@@ -45,6 +45,7 @@ int read_current_timer(unsigned long *timer_val)*timer_val=delay_timer->read_current_timer();return0;}+EXPORT_SYMBOL_GPL(read_current_timer);
Perhaps this fits better in armksyms.c? That way it lives with
arm_delay_ops and friends.
It's always much better to put things next to where they're defined
rather than spreading them around.
armksyms.c is a reminant of the 1.x days of doing things... but still
remains to allow what are mostly assembly symbols to be exported.
From: Russell King - ARM Linux <hidden> Date: 2012-10-09 16:08:30
On Tue, Oct 09, 2012 at 05:22:54PM +0200, Arnd Bergmann wrote:
Here are some patches that belong into your domain, I hope you can
just send the lot to Linus the next time you send other patches.
These bug fixes all address problems found with automated build testing.
Some of them have been around for a long time, other bugs are
regressions since the merge window.
Apart from the sliced off comment in one commit (which XEN people need
to confirm they're happy with the final version), I think these are
otherwise fine... I'll hold off pulling them until that can be fixed.
Thanks.
From: Ian Campbell <hidden> Date: 2012-10-09 16:10:40
On Tue, 2012-10-09 at 16:39 +0100, Arnd Bergmann wrote:
On Tuesday 09 October 2012, Ian Campbell wrote:
quoted
quoted
* The tmem hypercall is not available on ARM
* ARMv6 does not support cmpxchg on 16-bit words that are used in the
missing the end of this sentence?
Right, I meant to say
* ARMv6 does not support cmpxchg on 16-bit words that are used in the
Xen grant table code, so we must ensure that Xen support is only built
on ARMv7-only kernels not combined ARMv6/v7 kernels.
This should be fixed differently in the future.
Is this is a build time failure because gcc/gas/etc refuses to generate
these instructions if it is configured for v6?
I ask because if it is only a runtime issue then we can reason that if
we are running Xen specific grant table code, then we must be running on
Xen and therefore must necessarily be running on a v7 (because Xen only
support v7+virt extensions) even if the kernel happens to be capable of
running on v6 too.
Ian.
From: Thomas Gleixner <hidden> Date: 2012-10-09 16:20:28
On Tue, 9 Oct 2012, Arnd Bergmann wrote:
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!
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>
Acked-by-me
quoted hunk
Cc: Russell King <redacted>
---
arch/arm/kernel/irq.c | 2 ++
1 file changed, 2 insertions(+)
@@ -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__initinit_IRQ(void){
On Tue, 9 Oct 2012, Russell King - ARM Linux wrote:
On Tue, Oct 09, 2012 at 05:22:54PM +0200, Arnd Bergmann wrote:
quoted
Here are some patches that belong into your domain, I hope you can
just send the lot to Linus the next time you send other patches.
These bug fixes all address problems found with automated build testing.
Some of them have been around for a long time, other bugs are
regressions since the merge window.
Apart from the sliced off comment in one commit (which XEN people need
to confirm they're happy with the final version), I think these are
otherwise fine... I'll hold off pulling them until that can be fixed.
I am OK with the comment being truncated.
I am going to submit a better fix for the Kconfig issues separately
anyway, on top of this patch.
From: Dave Martin <hidden> Date: 2012-10-09 17:27:38
On Tue, Oct 09, 2012 at 05:23:00PM +0200, Arnd Bergmann wrote:
The Linaro cross toolchain and probably others nowadays default to
building in THUMB2 mode. When building a kernel for a CPU that does
not support THUMB2, the compiler complains about incorrect flags.
We can work around this by setting -marm for all non-T2 builds.
Without this patch, building assabet_defconfig results in:
usr/initramfs_data.S:1:0: warning: target CPU does not support THUMB instructions [enabled by default]
arch/arm/nwfpe/entry.S:1:0: warning: target CPU does not support THUMB instructions [enabled by default]
firmware/cis/PCMLM28.cis.gen.S:1:0: warning: target CPU does not support THUMB instructions [enabled by default]
(and many more)
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Nicolas Pitre <redacted>
Cc: Russell King <redacted>
Cc: Dave Martin <redacted>
This looks like a sensible fix, but it could be worth amending the
commit message to explain what was fixed, since it took me a moment or
two to puzzle out why the code this patch removes was broken. Maybe
something like:
-marm was passed unconditionally for C files previously, but nothing was
passed to the gcc frontend when processing .S files, resulting in a
warning. The assembler never defaults to ARM unless -Wa,-mthumb is
supplied explicitly, so the files were still assembled correctly.
This patch makes sure that -marm is passed for .S files too, and also
avoids the redundant gcc -marm -mthumb in Thumb kernels.
Preferably with that (or equivalent):
Acked-by: Dave Martin <redacted>
@@ -21,8 +21,6 @@ endifOBJCOPYFLAGS:=-Obinary-R.comment-SGZFLAGS:=-9#KBUILD_CFLAGS +=-pipe-# Explicitly specifiy 32-bit ARM ISA since toolchain default can be -mthumb:-KBUILD_CFLAGS+=$(callcc-option,-marm,)# Never generate .eh_frameKBUILD_CFLAGS+=$(callcc-option,-fno-dwarf2-cfi-asm)
@@ -105,17 +103,20 @@ endififeq ($(CONFIG_THUMB2_KERNEL),y)AFLAGS_AUTOIT:=$(callas-option,-Wa$(comma)-mimplicit-it=always,-Wa$(comma)-mauto-it)AFLAGS_NOWARN:=$(callas-option,-Wa$(comma)-mno-warn-deprecated,-Wa$(comma)-W)-CFLAGS_THUMB2:=-mthumb$(AFLAGS_AUTOIT)$(AFLAGS_NOWARN)-AFLAGS_THUMB2:=$(CFLAGS_THUMB2)-Wa$(comma)-mthumb+CFLAGS_ISA:=-mthumb$(AFLAGS_AUTOIT)$(AFLAGS_NOWARN)+AFLAGS_ISA:=$(CFLAGS_ISA)-Wa$(comma)-mthumb# Work around buggy relocation from gas if requested:ifeq ($(CONFIG_THUMB2_AVOID_R_ARM_THM_JUMP11),y)CFLAGS_MODULE+=-fno-optimize-sibling-callsendif+else+CFLAGS_ISA:=$(callcc-option,-marm,)+AFLAGS_ISA:=$(CFLAGS_ISA)endif# Need -Uarm for gcc < 3.x-KBUILD_CFLAGS+=$(CFLAGS_ABI)$(CFLAGS_THUMB2)$(arch-y)$(tune-y)$(callcc-option,-mshort-load-bytes,$(callcc-option,-malignment-traps,))-msoft-float-Uarm-KBUILD_AFLAGS+=$(CFLAGS_ABI)$(AFLAGS_THUMB2)$(arch-y)$(tune-y)-includeasm/unified.h-msoft-float+KBUILD_CFLAGS+=$(CFLAGS_ABI)$(CFLAGS_ISA)$(arch-y)$(tune-y)$(callcc-option,-mshort-load-bytes,$(callcc-option,-malignment-traps,))-msoft-float-Uarm+KBUILD_AFLAGS+=$(CFLAGS_ABI)$(AFLAGS_ISA)$(arch-y)$(tune-y)-includeasm/unified.h-msoft-floatCHECKFLAGS+=-D__arm__
On Tue, 2012-10-09 at 16:39 +0100, Arnd Bergmann wrote:
quoted
On Tuesday 09 October 2012, Ian Campbell wrote:
quoted
quoted
* The tmem hypercall is not available on ARM
* ARMv6 does not support cmpxchg on 16-bit words that are used in the
missing the end of this sentence?
Right, I meant to say
* ARMv6 does not support cmpxchg on 16-bit words that are used in the
Xen grant table code, so we must ensure that Xen support is only built
on ARMv7-only kernels not combined ARMv6/v7 kernels.
This should be fixed differently in the future.
Is this is a build time failure because gcc/gas/etc refuses to generate
these instructions if it is configured for v6?
I ask because if it is only a runtime issue then we can reason that if
we are running Xen specific grant table code, then we must be running on
Xen and therefore must necessarily be running on a v7 (because Xen only
support v7+virt extensions) even if the kernel happens to be capable of
running on v6 too.
The underlying reason of course is that ARMv6 doesn't have those
instructions. The symptom you see is a link error because gcc emits
a reference to the (intentionally missing) __bad_cmpxchg() function
from
static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
unsigned long new, int size)
{
unsigned long oldval, res;
switch (size) {
#ifndef CONFIG_CPU_V6 /* min ARCH >= ARMv6K */
case 1:
...
break;
case 2:
...
break;
#endif
case 4:
...
break;
default:
__bad_cmpxchg(ptr, size);
oldval = 0;
}
return oldval;
}
The possible solutions I can see for this are:
* change the grant table format to use 32 bits for the flags on ARM
* change the code to always cmpxchg the entire 32 bit word including the flags.
* implement your own cmpxchg wrapper that may be implemented using a spinlock
rather than cmpxchg if ARMv6 is enabled.
Arnd
On Tuesday 09 October 2012, Stefano Stabellini wrote:
quoted
config XEN
bool "Xen guest support on ARM (EXPERIMENTAL)"
depends on EXPERIMENTAL && ARM && OF
+ depends on !CPU_V6
help
Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
Considering that we rely on the virtualization extensions, this one can
be:
depends on CPU_V7
The rest looks fine. I can submit a second patch to change !CPU_V6 into
CPU_V7 later, if you prefer.
CPU_V6 and CPU_V7 are not exclusive, I saw the problem when building a
combined kernel for both V6 and V7. The code also needs to depend on ARMv7
with virtualization extensions, but that is a different issue. We don't
actually have a configuration symbol for that yet, as far as I can tell.
Arnd
On Tuesday 09 October 2012, Russell King - ARM Linux wrote:
On Tue, Oct 09, 2012 at 05:22:54PM +0200, Arnd Bergmann wrote:
quoted
Here are some patches that belong into your domain, I hope you can
just send the lot to Linus the next time you send other patches.
These bug fixes all address problems found with automated build testing.
Some of them have been around for a long time, other bugs are
regressions since the merge window.
Apart from the sliced off comment in one commit (which XEN people need
to confirm they're happy with the final version), I think these are
otherwise fine... I'll hold off pulling them until that can be fixed.
Fixed that now, and I also added the Acks that I got in the meantime,
changed the dependency from Xen on (CPU_v7 && !CPU_V6), and edited the
description for patch 6 as Dave suggested.
Arnd
8<---
The following changes since commit 0e51793e162ca432fc5f04178cf82b80a92c2659:
Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm (2012-10-07 21:20:57 +0900)
are available in the git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc.git tags/fixes-for-rmk
for you to fetch changes up to 8e7fc18b5eacc37b6e6fcf486ec4eafbfef91738:
ARM: warnings in arch/arm/include/asm/uaccess.h (2012-10-09 20:29:07 +0200)
----------------------------------------------------------------
These bug fixes all address problems found with automated build testing.
Some of them have been around for a long time, other bugs are
regressions since the merge window.
----------------------------------------------------------------
Arnd Bergmann (9):
ARM: kprobes: make more tests conditional
ARM: export set_irq_flags
ARM: Fix another build warning in arch/arm/mm/alignment.c
ARM: export default read_current_timer
ARM: Xen: fix initial build problems
ARM: pass -marm to gcc by default for both C and assembler
ARM: be really quiet when building with 'make -s'
ARM: binfmt_flat: unused variable 'persistent'
ARM: warnings in arch/arm/include/asm/uaccess.h
arch/arm/Kconfig | 1 +
arch/arm/Makefile | 13 +++++++------
arch/arm/boot/Makefile | 10 +++++-----
arch/arm/include/asm/flat.h | 2 +-
arch/arm/include/asm/uaccess.h | 4 ++--
arch/arm/kernel/irq.c | 2 ++
arch/arm/kernel/kprobes-test-arm.c | 4 ++++
arch/arm/lib/delay.c | 1 +
arch/arm/mm/alignment.c | 4 +++-
arch/arm/tools/Makefile | 2 +-
drivers/xen/Kconfig | 2 ++
drivers/xen/sys-hypervisor.c | 1 +
12 files changed, 30 insertions(+), 16 deletions(-)
On Tue, Oct 9, 2012 at 5:22 PM, Arnd Bergmann [off-list ref] wrote:
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!
We either need to replace the call to set_irq_flags with something
else or export that function. This patch does the latter.
Argh! And I cannot think of anything more elegant so
Acked-by: Linus Walleij <redacted>
Yours,
Linus Walleij
From: Ian Campbell <hidden> Date: 2012-10-10 07:54:53
On Tue, 2012-10-09 at 19:21 +0100, Arnd Bergmann wrote:
On Tuesday 09 October 2012, Stefano Stabellini wrote:
quoted
quoted
config XEN
bool "Xen guest support on ARM (EXPERIMENTAL)"
depends on EXPERIMENTAL && ARM && OF
+ depends on !CPU_V6
help
Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
Considering that we rely on the virtualization extensions, this one can
be:
depends on CPU_V7
The rest looks fine. I can submit a second patch to change !CPU_V6 into
CPU_V7 later, if you prefer.
CPU_V6 and CPU_V7 are not exclusive, I saw the problem when building a
combined kernel for both V6 and V7. The code also needs to depend on ARMv7
with virtualization extensions, but that is a different issue. We don't
actually have a configuration symbol for that yet, as far as I can tell.
I don't think the guest kernels (including dom0) need the extensions to
run under Xen, they are only need by Xen itself. The guests should just
see a relatively normal v7 processor.
Stefano, does that sound right?
Ian.
From: Ian Campbell <hidden> Date: 2012-10-10 09:46:38
On Tue, 2012-10-09 at 19:19 +0100, Arnd Bergmann wrote:
On Tuesday 09 October 2012, Ian Campbell wrote:
quoted
On Tue, 2012-10-09 at 16:39 +0100, Arnd Bergmann wrote:
quoted
On Tuesday 09 October 2012, Ian Campbell wrote:
quoted
quoted
* The tmem hypercall is not available on ARM
* ARMv6 does not support cmpxchg on 16-bit words that are used in the
missing the end of this sentence?
Right, I meant to say
* ARMv6 does not support cmpxchg on 16-bit words that are used in the
Xen grant table code, so we must ensure that Xen support is only built
on ARMv7-only kernels not combined ARMv6/v7 kernels.
This should be fixed differently in the future.
Is this is a build time failure because gcc/gas/etc refuses to generate
these instructions if it is configured for v6?
I ask because if it is only a runtime issue then we can reason that if
we are running Xen specific grant table code, then we must be running on
Xen and therefore must necessarily be running on a v7 (because Xen only
support v7+virt extensions) even if the kernel happens to be capable of
running on v6 too.
The underlying reason of course is that ARMv6 doesn't have those
instructions. The symptom you see is a link error because gcc emits
a reference to the (intentionally missing) __bad_cmpxchg() function
from
OK, then your fix is the best one for now.
[...]
The possible solutions I can see for this are:
* change the grant table format to use 32 bits for the flags on ARM
* change the code to always cmpxchg the entire 32 bit word including the flags.
I'd need to check the grant table semantics to see if this will be
possible.
* implement your own cmpxchg wrapper that may be implemented using a spinlock
rather than cmpxchg if ARMv6 is enabled.
Even if ARMv6 is enabled the grant table code will never be running on
one so so it might be ok to just have our own wrapper which
unconditionally uses the v7 instruction? That might upset gas though.
* implement your own cmpxchg wrapper that may be implemented using a spinlock
rather than cmpxchg if ARMv6 is enabled.
Even if ARMv6 is enabled the grant table code will never be running on
one so so it might be ok to just have our own wrapper which
unconditionally uses the v7 instruction? That might upset gas though.
Yes, that would be possible. You can tell gas to ignore the instruction
set in this case. If you do this, you can implement the update functions
more efficiently using direct ldrexh/strexh in assembler to avoid doing
two nested loops. I assume that you don't need the v1 grant table
code on ARM anyway, so the only code you need to look at is
while (!((flags = *pflags) & GTF_transfer_committed)) {
if (sync_cmpxchg(pflags, flags, 0) == flags)
return 0;
cpu_relax();
}
which should transform nicely into a few lines of inline assembly.
Arnd
On Tue, 2012-10-09 at 19:21 +0100, Arnd Bergmann wrote:
quoted
On Tuesday 09 October 2012, Stefano Stabellini wrote:
quoted
quoted
config XEN
bool "Xen guest support on ARM (EXPERIMENTAL)"
depends on EXPERIMENTAL && ARM && OF
+ depends on !CPU_V6
help
Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
Considering that we rely on the virtualization extensions, this one can
be:
depends on CPU_V7
The rest looks fine. I can submit a second patch to change !CPU_V6 into
CPU_V7 later, if you prefer.
CPU_V6 and CPU_V7 are not exclusive, I saw the problem when building a
combined kernel for both V6 and V7. The code also needs to depend on ARMv7
with virtualization extensions, but that is a different issue. We don't
actually have a configuration symbol for that yet, as far as I can tell.
I don't think the guest kernels (including dom0) need the extensions to
run under Xen, they are only need by Xen itself. The guests should just
see a relatively normal v7 processor.
Stefano, does that sound right?
Keep in mind that we are using HVC to issue hypercalls, and HVC has been
introduced with the virtualization extensions, if I am not mistaken.
From: Ian Campbell <hidden> Date: 2012-10-10 14:53:50
On Wed, 2012-10-10 at 15:47 +0100, Stefano Stabellini wrote:
On Wed, 10 Oct 2012, Ian Campbell wrote:
quoted
On Tue, 2012-10-09 at 19:21 +0100, Arnd Bergmann wrote:
quoted
On Tuesday 09 October 2012, Stefano Stabellini wrote:
quoted
quoted
config XEN
bool "Xen guest support on ARM (EXPERIMENTAL)"
depends on EXPERIMENTAL && ARM && OF
+ depends on !CPU_V6
help
Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
Considering that we rely on the virtualization extensions, this one can
be:
depends on CPU_V7
The rest looks fine. I can submit a second patch to change !CPU_V6 into
CPU_V7 later, if you prefer.
CPU_V6 and CPU_V7 are not exclusive, I saw the problem when building a
combined kernel for both V6 and V7. The code also needs to depend on ARMv7
with virtualization extensions, but that is a different issue. We don't
actually have a configuration symbol for that yet, as far as I can tell.
I don't think the guest kernels (including dom0) need the extensions to
run under Xen, they are only need by Xen itself. The guests should just
see a relatively normal v7 processor.
Stefano, does that sound right?
Keep in mind that we are using HVC to issue hypercalls, and HVC has been
introduced with the virtualization extensions, if I am not mistaken.
I think we can ignore that in this context since it is only used by bits
which are already virtualisation aware -- i.e. you wouldn't want to add
it to the Kconfig as a dependency for Xen.
Ian.
On Tuesday 09 October 2012, Russell King - ARM Linux wrote:
quoted
On Tue, Oct 09, 2012 at 05:22:54PM +0200, Arnd Bergmann wrote:
quoted
Here are some patches that belong into your domain, I hope you can
just send the lot to Linus the next time you send other patches.
These bug fixes all address problems found with automated build testing.
Some of them have been around for a long time, other bugs are
regressions since the merge window.
Apart from the sliced off comment in one commit (which XEN people need
to confirm they're happy with the final version), I think these are
otherwise fine... I'll hold off pulling them until that can be fixed.
Fixed that now, and I also added the Acks that I got in the meantime,
changed the dependency from Xen on (CPU_v7 && !CPU_V6), and edited the
description for patch 6 as Dave suggested.
Thanks for the update, the new Xen patch is fine by me
On Wed, 2012-10-10 at 15:47 +0100, Stefano Stabellini wrote:
quoted
On Wed, 10 Oct 2012, Ian Campbell wrote:
quoted
On Tue, 2012-10-09 at 19:21 +0100, Arnd Bergmann wrote:
quoted
On Tuesday 09 October 2012, Stefano Stabellini wrote:
quoted
quoted
config XEN
bool "Xen guest support on ARM (EXPERIMENTAL)"
depends on EXPERIMENTAL && ARM && OF
+ depends on !CPU_V6
help
Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
Considering that we rely on the virtualization extensions, this one can
be:
depends on CPU_V7
The rest looks fine. I can submit a second patch to change !CPU_V6 into
CPU_V7 later, if you prefer.
CPU_V6 and CPU_V7 are not exclusive, I saw the problem when building a
combined kernel for both V6 and V7. The code also needs to depend on ARMv7
with virtualization extensions, but that is a different issue. We don't
actually have a configuration symbol for that yet, as far as I can tell.
I don't think the guest kernels (including dom0) need the extensions to
run under Xen, they are only need by Xen itself. The guests should just
see a relatively normal v7 processor.
Stefano, does that sound right?
Keep in mind that we are using HVC to issue hypercalls, and HVC has been
introduced with the virtualization extensions, if I am not mistaken.
I think we can ignore that in this context since it is only used by bits
which are already virtualisation aware -- i.e. you wouldn't want to add
it to the Kconfig as a dependency for Xen.
Considering that ARM CPU_V* symbols are not mutually exclusive, if Linux
had a CPU_V7_VIRTEXT symbol I don't see why we shouldn't add it to our
list of dependencies. It is more accurate than CPU_V7 after all.
But I don't think that it is necessary to introduce one now only for
Xen, because like you said, we only need HVC and that is only used in
virtualization aware code.
From: Will Deacon <hidden> Date: 2012-10-12 13:20:41
Hi Arnd, Russell,
On Tue, Oct 09, 2012 at 07:40:24PM +0100, Arnd Bergmann wrote:
On Tuesday 09 October 2012, Russell King - ARM Linux wrote:
quoted
On Tue, Oct 09, 2012 at 05:22:54PM +0200, Arnd Bergmann wrote:
quoted
Here are some patches that belong into your domain, I hope you can
just send the lot to Linus the next time you send other patches.
These bug fixes all address problems found with automated build testing.
Some of them have been around for a long time, other bugs are
regressions since the merge window.
Apart from the sliced off comment in one commit (which XEN people need
to confirm they're happy with the final version), I think these are
otherwise fine... I'll hold off pulling them until that can be fixed.
Fixed that now, and I also added the Acks that I got in the meantime,
changed the dependency from Xen on (CPU_v7 && !CPU_V6), and edited the
description for patch 6 as Dave suggested.
Arnd
8<---
The following changes since commit 0e51793e162ca432fc5f04178cf82b80a92c2659:
Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm (2012-10-07 21:20:57 +0900)
are available in the git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc.git tags/fixes-for-rmk
for you to fetch changes up to 8e7fc18b5eacc37b6e6fcf486ec4eafbfef91738:
ARM: warnings in arch/arm/include/asm/uaccess.h (2012-10-09 20:29:07 +0200)
It would be good to see these for -rc1 if there's still time. I'm tired of
seeing patches to fix the export of the read_current_timer symbol!
Cheers,
Will
@@ -45,6 +45,7 @@ int read_current_timer(unsigned long *timer_val)*timer_val=delay_timer->read_current_timer();return0;}+EXPORT_SYMBOL_GPL(read_current_timer);
Perhaps this fits better in armksyms.c? That way it lives with
arm_delay_ops and friends.
It's always much better to put things next to where they're defined
rather than spreading them around.
armksyms.c is a reminant of the 1.x days of doing things... but still
remains to allow what are mostly assembly symbols to be exported.
I needed that to build udlfb as a module.
For the 3.6 stable kernels this has to be done in
arch/arm/kernel/arch_timer.c (along with an #include <linux/export.h>)
So I'm not sure if an Cc: [off-list ref] can be used here, but
a patch should be submitted for inclusion into the 3.6 stable series too.
Regards,
Alexander