linux-stable.git/arch/arm/kernel/return_address.c, branch v3.2.97 Linux kernel stable tree ARM: 8160/1: drop warning about return_address not using unwind tables 2017-11-11T13:34:51+00:00 Uwe Kleine-König u.kleine-koenig@pengutronix.de 2014-09-24T07:51:57+00:00 747ea873db4fb9836bacfdc6f4d7d7d11d3d808d commit e16343c47e4276f5ebc77ca16feb5e50ca1918f9 upstream. The warning was introduced in 2009 (commit 4bf1fa5a34aa ([ARM] 5613/1: implement CALLER_ADDRESSx)). The only "problem" here is that CALLER_ADDRESSx for x > 1 returns NULL which doesn't do much harm. The drawback of implementing a fix (i.e. use unwind tables to implement CALLER_ADDRESSx) is that much of the unwinder code would need to be marked as not traceable. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit e16343c47e4276f5ebc77ca16feb5e50ca1918f9 upstream.

The warning was introduced in 2009 (commit 4bf1fa5a34aa ([ARM] 5613/1:
implement CALLER_ADDRESSx)). The only "problem" here is that
CALLER_ADDRESSx for x > 1 returns NULL which doesn't do much harm.

The drawback of implementing a fix (i.e. use unwind tables to implement CALLER_ADDRESSx) is that much of the unwinder code would need to be marked as not
traceable.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
arm: convert core files from module.h to export.h 2011-10-31T23:30:49+00:00 Paul Gortmaker paul.gortmaker@windriver.com 2011-07-22T14:58:34+00:00 ecea4ab6d3d8bb4122522398200f1cd2a06af6d5 Many of the core ARM kernel files are not modules, but just including module.h for exporting symbols. Now these files can use the lighter footprint export.h for this role. There are probably lots more, but ARM files of mach-* and plat-* don't get coverage via a simple yesconfig build. They will have to be cleaned up and tested via using their respective configs. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> 
Many of the core ARM kernel files are not modules, but just
including module.h for exporting symbols.  Now these files can
use the lighter footprint export.h for this role.

There are probably lots more, but ARM files of mach-* and plat-*
don't get coverage via a simple yesconfig build.  They will have
to be cleaned up and tested via using their respective configs.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
ARM: fix some sparse errors in generic ARM code 2011-02-23T17:24:12+00:00 Russell King rmk+kernel@arm.linux.org.uk 2011-01-08T12:05:09+00:00 2bbd7e9b74271b2d6a14b4840fc44afbea83774d arch/arm/kernel/return_address.c:37:6: warning: symbol 'return_address' was not declared. Should it be static? arch/arm/kernel/setup.c:76:14: warning: symbol 'processor_id' was not declared. Should it be static? arch/arm/kernel/traps.c:259:1: warning: symbol 'die_lock' was not declared. Should it be static? arch/arm/vfp/vfpmodule.c:156:6: warning: symbol 'vfp_raise_sigfpe' was not declared. Should it be static? Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
arch/arm/kernel/return_address.c:37:6: warning: symbol 'return_address' was not declared. Should it be static?
arch/arm/kernel/setup.c:76:14: warning: symbol 'processor_id' was not declared. Should it be static?
arch/arm/kernel/traps.c:259:1: warning: symbol 'die_lock' was not declared. Should it be static?
arch/arm/vfp/vfpmodule.c:156:6: warning: symbol 'vfp_raise_sigfpe' was not declared. Should it be static?

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[ARM] 5613/1: implement CALLER_ADDRESSx 2009-07-21T16:21:28+00:00 Uwe Kleine-König u.kleine-koenig@pengutronix.de 2009-07-21T08:56:27+00:00 4bf1fa5a34aa2dd0d2cc58f0fc213a2e22d007a4 From: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> As __builtin_return_address(n) doesn't work for ARM with n > 0, the kernel needs its own implementation. This fixes many warnings saying: warning: unsupported argument to '__builtin_return_address' The new methods and walk_stackframe must not be instrumented because CALLER_ADDRESSx is used in the various tracers and tracing the tracer is a bad idea. What's currently missing is an implementation using unwind tables. This is not fatal though, it's just that the tracers don't get enough information to be really useful. Note that if both ARM_UNWIND and FRAME_POINTER are enabled, walk_stackframe uses unwind information. So in this case the same implementation is used as when FRAME_POINTER is disabled. Cc: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
From: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

As __builtin_return_address(n) doesn't work for ARM with n > 0, the
kernel needs its own implementation.

This fixes many warnings saying:

	warning: unsupported argument to '__builtin_return_address'

The new methods and walk_stackframe must not be instrumented because
CALLER_ADDRESSx is used in the various tracers and tracing the tracer is
a bad idea.

What's currently missing is an implementation using unwind tables.  This
is not fatal though, it's just that the tracers don't get enough
information to be really useful.

Note that if both ARM_UNWIND and FRAME_POINTER are enabled,
walk_stackframe uses unwind information.  So in this case the same
implementation is used as when FRAME_POINTER is disabled.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>