Commit Graph

17 Commits

Author SHA1 Message Date
Peter Zijlstra
b5effd3815 debug: Fix __bug_table[] in arch linker scripts
The kbuild test robot reported this build failure on a number
of architectures:

 >         make.cross ARCH=arm
 >    lib/lib.a(bug.o): In function `find_bug':
 > >> lib/bug.c:135: undefined reference to `__start___bug_table'
 > >> lib/bug.c:135: undefined reference to `__stop___bug_table'

Caused by:

  19d436268d ("debug: Add _ONCE() logic to report_bug()")

Which moved the BUG_TABLE from RO_DATA_SECTION() to RW_DATA_SECTION(),
but a number of architectures don't use RW_DATA_SECTION(), so they
ended up with no __bug_table[] ...

Ideally all those would use RW_DATA_SECTION() in their linker scripts,
but that's for another day.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kbuild test robot <fengguang.wu@intel.com>
Cc: kbuild-all@01.org
Cc: tipbuild@zytor.com
Link: http://lkml.kernel.org/r/20170330154927.o6qmgfp4bdhrajbm@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-03 10:22:40 +02:00
Chris Metcalf
6727ad9e20 nmi_backtrace: generate one-line reports for idle cpus
When doing an nmi backtrace of many cores, most of which are idle, the
output is a little overwhelming and very uninformative.  Suppress
messages for cpus that are idling when they are interrupted and just
emit one line, "NMI backtrace for N skipped: idling at pc 0xNNN".

We do this by grouping all the cpuidle code together into a new
.cpuidle.text section, and then checking the address of the interrupted
PC to see if it lies within that section.

This commit suitably tags x86 and tile idle routines, and only adds in
the minimal framework for other architectures.

Link: http://lkml.kernel.org/r/1472487169-14923-5-git-send-email-cmetcalf@mellanox.com
Signed-off-by: Chris Metcalf <cmetcalf@mellanox.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Daniel Thompson <daniel.thompson@linaro.org> [arm]
Tested-by: Petr Mladek <pmladek@suse.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-07 18:46:30 -07:00
Guenter Roeck
f9f3f864b5 cris: Fix section mismatches in architecture startup code
Section mismatches can now result in build failures.
As result, cris:allnoconfig fails to build as follows.

WARNING: modpost: Found 7 section mismatch(es).
To see full details build your kernel with:
'make CONFIG_DEBUG_SECTION_MISMATCH=y'
FATAL: modpost: Section mismatches detected.
Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.

Part of the problem is that references from .text to .init.text
are not permitted, and such references are used in cris startup code.
Since references from .head.text to .init.text are permitted, move
cris startup code to a new section .head.text.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
2015-12-15 14:03:19 +01:00
Jesper Nilsson
473e162eea CRIS: Add _sdata to vmlinux.lds.S
Fixes link error:
  LD      vmlinux
kernel/built-in.o: In function `core_kernel_data':
(.text+0x13e44): undefined reference to `_sdata'

Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
2012-04-03 13:26:33 +02:00
Tejun Heo
0415b00d17 percpu: Always align percpu output section to PAGE_SIZE
Percpu allocator honors alignment request upto PAGE_SIZE and both the
percpu addresses in the percpu address space and the translated kernel
addresses should be aligned accordingly.  The calculation of the
former depends on the alignment of percpu output section in the kernel
image.

The linker script macros PERCPU_VADDR() and PERCPU() are used to
define this output section and the latter takes @align parameter.
Several architectures are using @align smaller than PAGE_SIZE breaking
percpu memory alignment.

This patch removes @align parameter from PERCPU(), renames it to
PERCPU_SECTION() and makes it always align to PAGE_SIZE.  While at it,
add PCPU_SETUP_BUG_ON() checks such that alignment problems are
reliably detected and remove percpu alignment comment recently added
in workqueue.c as the condition would trigger BUG way before reaching
there.

For um, this patch raises the alignment of percpu area.  As the area
is in .init, there shouldn't be any noticeable difference.

This problem was discovered by David Howells while debugging boot
failure on mn10300.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Cc: uclinux-dist-devel@blackfin.uclinux.org
Cc: David Howells <dhowells@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: user-mode-linux-devel@lists.sourceforge.net
2011-03-24 18:50:09 +01:00
Linus Torvalds
79d8a8f736 Merge branch 'for-2.6.39' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-2.6.39' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu, x86: Add arch-specific this_cpu_cmpxchg_double() support
  percpu: Generic support for this_cpu_cmpxchg_double()
  alpha: use L1_CACHE_BYTES for cacheline size in the linker script
  percpu: align percpu readmostly subsection to cacheline

Fix up trivial conflict in arch/x86/kernel/vmlinux.lds.S due to the
percpu alignment having changed ("x86: Reduce back the alignment of the
per-CPU data section")
2011-03-16 08:22:41 -07:00
Jesper Nilsson
f19e0eec8b Drop redundant __param section for CRISv32.
The __param section is already brought in by RODATA above.

Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-23 08:00:47 -08:00
Tejun Heo
19df0c2fef percpu: align percpu readmostly subsection to cacheline
Currently percpu readmostly subsection may share cachelines with other
percpu subsections which may result in unnecessary cacheline bounce
and performance degradation.

This patch adds @cacheline parameter to PERCPU() and PERCPU_VADDR()
linker macros, makes each arch linker scripts specify its cacheline
size and use it to align percpu subsections.

This is based on Shaohua's x86 only patch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Shaohua Li <shaohua.li@intel.com>
2011-01-25 14:26:50 +01:00
Jesper Nilsson
85d9865721 CRIS: Fix alignment problem for older ld
CRISv10 uses a pretty old ld, which does not allow ALIGN(0),
(It becomes . = 0;) so instead we align to 1 byte.

Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
2010-08-04 18:30:01 +02:00
Jesper Nilsson
7c8a25b544 CRIS: Discard exit.text and .data at runtime
This allows us to handle references from __bug_table.

Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
2010-08-04 14:10:04 +02:00
Jesper Nilsson
dcb313c23f CRIS: Add cache aligned and read mostly data sections
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
2010-08-04 14:03:07 +02:00
Sam Ravnborg
98b8788ae9 drop explicit include of autoconf.h
kbuild.h forces include of autoconf.h on the
commandline using -include - so we do not need to
include the file explicit.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2009-12-12 13:08:15 +01:00
Linus Torvalds
5f8fe4270e Merge branch 'for-linus' of git://repo.or.cz/cris-mirror
* 'for-linus' of git://repo.or.cz/cris-mirror:
  CRIS: Cleanup linker script using new linker script macros.
  ARRAY_SIZE changes
  CRIS: convert to asm-generic/hardirq.h
  CRISv10: Don't autonegotiate if autonegotiation is off
  CRIS: fix defconfig build failure
  CRIS: add pgprot_noncached
2009-09-24 17:08:56 -07:00
Jesper Nilsson
24924ece44 CRIS: Cleanup linker script using new linker script macros.
Signed-off-by: Tim Abbott <tabbott@ksplice.com>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
2009-09-23 13:21:57 +02:00
Tejun Heo
023bf6f1b8 linker script: unify usage of discard definition
Discarded sections in different archs share some commonality but have
considerable differences.  This led to linker script for each arch
implementing its own /DISCARD/ definition, which makes maintaining
tedious and adding new entries error-prone.

This patch makes all linker scripts to move discard definitions to the
end of the linker script and use the common DISCARDS macro.  As ld
uses the first matching section definition, archs can include default
discarded sections by including them earlier in the linker script.

ia64 is notable because it first throws away some ia64 specific
subsections and then include the rest of the sections into the final
image, so those sections must be discarded before the inclusion.

defconfig compile tested for x86, x86-64, powerpc, powerpc64, ia64,
alpha, sparc, sparc64 and s390.  Michal Simek tested microblaze.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Tested-by: Michal Simek <monstr@monstr.eu>
Cc: linux-arch@vger.kernel.org
Cc: Michal Simek <monstr@monstr.eu>
Cc: microblaze-uclinux@itee.uq.edu.au
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Tony Luck <tony.luck@intel.com>
2009-07-09 11:27:40 +09:00
Tejun Heo
405d967dc7 linker script: throw away .discard section
x86 throws away .discard section but no other archs do.  Also,
.discard is not thrown away while linking modules.  Make every arch
and module linking throw it away.  This will be used to define dummy
variables for percpu declarations and definitions.

This patch is based on Ivan Kokshaysky's alpha percpu patch.

[ Impact: always throw away everything in .discard ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Bryan Wu <cooloney@kernel.org>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Ingo Molnar <mingo@elte.hu>
2009-06-24 15:13:38 +09:00
Jesper Nilsson
c5ec6fb08d [CRIS] Remove links from CRIS build
Remove the links to architecture and machine dependent directories
(boot, lib, drivers, arch, mach)

The links were created and used mostly from the arch/cris/Makefile,
so why not dispense with them altogether?
Changed $(ARCH) to "cris" in Makefile, it is easier to read this way.

The CRISv32 head.S common files for the kernel and compressed images
needed to be modified to use ifdefs instead of using the now removed
mach link. Since there are only two versions, this is not a huge loss
in readability.

The link to vmlinux.lds.S is also replaced with a merged version
which uses ifdefs to select the correct layout.
System.map before and after are identical.

Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2008-10-31 23:37:57 +01:00