For CONFIG_STRICT_KERNEL_RWX align __init_begin to 16M. We use 16M
since its the larger of 2M on radix and 16M on hash for our linear
mapping. The plan is to have .text, .rodata and everything upto
__init_begin marked as RX. Note we still have executable read only
data. We could further align rodata to another 16M boundary. I've used
keeping text plus rodata as read-only-executable as a trade-off to
doing read-only-executable for text and read-only for rodata.
We don't use multi PT_LOAD in PHDRS because we are not sure if all
bootloaders support them. This patch keeps PHDRS in vmlinux.lds.S as
the same they are with just one PT_LOAD for all of the kernel marked
as RWX (7).
mpe: What this means is the added alignment bloats the resulting
binary on disk, a powernv kernel goes from 17M to 22M.
Signed-off-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Add --orphan-handling=warn to final link flags. This ensures we can
handle all sections explicitly. This would have caught subtle breakage
such as 7de3b27bac at build-time.
Also bring existing orphan sections into the fold:
- .text.hot and .text.unlikely are compiler generated sections.
- .sdata2, .dynsbss, .plt are used by PPC32
- We previously did not specify DWARF_DEBUG or STABS_DEBUG
- DWARF_DEBUG did not include all DWARF sections that can be emitted
- A number of sections are unused and can be discarded.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Use a tool to check that the location of "fixed sections" are where
we expected them to be, which catches cases the linker script can't
(stubs being added to start of .text section), and which ends up
being neater.
Sample output:
ERROR: start_text address is c000000000008100, should be c000000000008000
ERROR: see comments in arch/powerpc/tools/head_check.sh
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Fold in fix from Nick for 4.6 era toolchains]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Very large kernels may require linker stubs for branches from HEAD
text code. The linker may place these stubs before the HEAD text
sections, which breaks the assumption that HEAD text is located at 0
(or the .text section being located at 0x7000/0x8000 on Book3S
kernels).
Provide an option to create a small section just before the .text
section with an empty 256 - 4 bytes, and adjust the start of the .text
section to match. The linker will tend to put stubs in that section
and not break our relative-to-absolute offset assumptions.
This causes a small waste of space on common kernels, but allows large
kernels to build and boot. For now, it is an EXPERT config option,
defaulting to =n, but a reference is provided for it in the build-time
check for such breakage. This is good enough for allyesconfig and
custom users / hackers.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Highlights include:
- Larger virtual address space on 64-bit server CPUs. By default we use a 128TB
virtual address space, but a process can request access to the full 512TB by
passing a hint to mmap().
- Support for the new Power9 "XIVE" interrupt controller.
- TLB flushing optimisations for the radix MMU on Power9.
- Support for CAPI cards on Power9, using the "Coherent Accelerator Interface
Architecture 2.0".
- The ability to configure the mmap randomisation limits at build and runtime.
- Several small fixes and cleanups to the kprobes code, as well as support for
KPROBES_ON_FTRACE.
- Major improvements to handling of system reset interrupts, correctly treating
them as NMIs, giving them a dedicated stack and using a new hypervisor call
to trigger them, all of which should aid debugging and robustness.
Many fixes and other minor enhancements.
Thanks to:
Alastair D'Silva, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan,
Aneesh Kumar K.V, Anshuman Khandual, Anton Blanchard, Balbir Singh, Ben
Hutchings, Benjamin Herrenschmidt, Bhupesh Sharma, Chris Packham, Christian
Zigotzky, Christophe Leroy, Christophe Lombard, Daniel Axtens, David Gibson,
Gautham R. Shenoy, Gavin Shan, Geert Uytterhoeven, Guilherme G. Piccoli,
Hamish Martin, Hari Bathini, Kees Cook, Laurent Dufour, Madhavan Srinivasan,
Mahesh J Salgaonkar, Mahesh Salgaonkar, Masami Hiramatsu, Matt Brown, Matthew
R. Ochs, Michael Neuling, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran,
Pan Xinhui, Paul Mackerras, Rashmica Gupta, Russell Currey, Sukadev
Bhattiprolu, Thadeu Lima de Souza Cascardo, Tobin C. Harding, Tyrel Datwyler,
Uma Krishnan, Vaibhav Jain, Vipin K Parashar, Yang Shi.
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Merge tag 'powerpc-4.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"Highlights include:
- Larger virtual address space on 64-bit server CPUs. By default we
use a 128TB virtual address space, but a process can request access
to the full 512TB by passing a hint to mmap().
- Support for the new Power9 "XIVE" interrupt controller.
- TLB flushing optimisations for the radix MMU on Power9.
- Support for CAPI cards on Power9, using the "Coherent Accelerator
Interface Architecture 2.0".
- The ability to configure the mmap randomisation limits at build and
runtime.
- Several small fixes and cleanups to the kprobes code, as well as
support for KPROBES_ON_FTRACE.
- Major improvements to handling of system reset interrupts,
correctly treating them as NMIs, giving them a dedicated stack and
using a new hypervisor call to trigger them, all of which should
aid debugging and robustness.
- Many fixes and other minor enhancements.
Thanks to: Alastair D'Silva, Alexey Kardashevskiy, Alistair Popple,
Andrew Donnellan, Aneesh Kumar K.V, Anshuman Khandual, Anton
Blanchard, Balbir Singh, Ben Hutchings, Benjamin Herrenschmidt,
Bhupesh Sharma, Chris Packham, Christian Zigotzky, Christophe Leroy,
Christophe Lombard, Daniel Axtens, David Gibson, Gautham R. Shenoy,
Gavin Shan, Geert Uytterhoeven, Guilherme G. Piccoli, Hamish Martin,
Hari Bathini, Kees Cook, Laurent Dufour, Madhavan Srinivasan, Mahesh J
Salgaonkar, Mahesh Salgaonkar, Masami Hiramatsu, Matt Brown, Matthew
R. Ochs, Michael Neuling, Naveen N. Rao, Nicholas Piggin, Oliver
O'Halloran, Pan Xinhui, Paul Mackerras, Rashmica Gupta, Russell
Currey, Sukadev Bhattiprolu, Thadeu Lima de Souza Cascardo, Tobin C.
Harding, Tyrel Datwyler, Uma Krishnan, Vaibhav Jain, Vipin K Parashar,
Yang Shi"
* tag 'powerpc-4.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (214 commits)
powerpc/64s: Power9 has no LPCR[VRMASD] field so don't set it
powerpc/powernv: Fix TCE kill on NVLink2
powerpc/mm/radix: Drop support for CPUs without lockless tlbie
powerpc/book3s/mce: Move add_taint() later in virtual mode
powerpc/sysfs: Move #ifdef CONFIG_HOTPLUG_CPU out of the function body
powerpc/smp: Document irq enable/disable after migrating IRQs
powerpc/mpc52xx: Don't select user-visible RTAS_PROC
powerpc/powernv: Document cxl dependency on special case in pnv_eeh_reset()
powerpc/eeh: Clean up and document event handling functions
powerpc/eeh: Avoid use after free in eeh_handle_special_event()
cxl: Mask slice error interrupts after first occurrence
cxl: Route eeh events to all drivers in cxl_pci_error_detected()
cxl: Force context lock during EEH flow
powerpc/64: Allow CONFIG_RELOCATABLE if COMPILE_TEST
powerpc/xmon: Teach xmon oops about radix vectors
powerpc/mm/hash: Fix off-by-one in comment about kernel contexts ids
powerpc/pseries: Enable VFIO
powerpc/powernv: Fix iommu table size calculation hook for small tables
powerpc/powernv: Check kzalloc() return value in pnv_pci_table_alloc
powerpc: Add arch/powerpc/tools directory
...
Introduce __head_end to mark end of the early fixed sections and use it to
blacklist all exception handlers from kprobes.
mpe: We do not need to do anything special for relocatable kernels, where the
exception vectors are split from the main kernel, as the split vectors are
already excluded by the check for kernel_text_address().
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
[mpe: Move __head_end outside #ifdef 64-bit to unbreak the 32-bit build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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>
Do not introduce any additional alignment. Placement of text section
will be set by fixed section macros. Without this, output section
alignment defaults to 4096, which makes BookE text section start at
0x1000 when it is expected to start at 0x100.
This was introduced by commit 57f266497d ("powerpc: Use gas sections
for arranging exception vectors") and was caught with the scripted head
section checker (not yet merged).
Fixes: 57f266497d ("powerpc: Use gas sections for arranging exception vectors")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Merge updates from Andrew Morton:
- fsnotify updates
- ocfs2 updates
- all of MM
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (127 commits)
console: don't prefer first registered if DT specifies stdout-path
cred: simpler, 1D supplementary groups
CREDITS: update Pavel's information, add GPG key, remove snail mail address
mailmap: add Johan Hovold
.gitattributes: set git diff driver for C source code files
uprobes: remove function declarations from arch/{mips,s390}
spelling.txt: "modeled" is spelt correctly
nmi_backtrace: generate one-line reports for idle cpus
arch/tile: adopt the new nmi_backtrace framework
nmi_backtrace: do a local dump_stack() instead of a self-NMI
nmi_backtrace: add more trigger_*_cpu_backtrace() methods
min/max: remove sparse warnings when they're nested
Documentation/filesystems/proc.txt: add more description for maps/smaps
mm, proc: fix region lost in /proc/self/smaps
proc: fix timerslack_ns CAP_SYS_NICE check when adjusting self
proc: add LSM hook checks to /proc/<tid>/timerslack_ns
proc: relax /proc/<tid>/timerslack_ns capability requirements
meminfo: break apart a very long seq_printf with #ifdefs
seq/proc: modify seq_put_decimal_[u]ll to take a const char *, not char
proc: faster /proc/*/status
...
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>
Use assembler sections of fixed size and location to arrange the 64-bit
Book3S exception vector code (64-bit Book3E also uses it in head_64.S
for 0x0..0x100).
This allows better flexibility in arranging exception code and hiding
unimportant details behind macros.
Gas sections can be a bit painful to use this way, mainly because the
assembler does not know where they will be finally linked. Taking
absolute addresses requires a bit of trickery for example, but it can
be hidden behind macros for the most part.
Generated code is mostly the same except locations, offsets, alignments.
The "+ 0x2" is only required for the trap number / kvm exit number,
which gets loaded as a constant into a register.
Previously, code also used + 0x2 for label names, but we changed to
using "H" to distinguish HV case for that. Remove the last vestiges
of that.
__after_prom_start is taking absolute address of a label in another
fixed section. Newer toolchains seemed to compile this okay, but older
ones do not. FIXED_SYMBOL_ABS_ADDR is more foolproof, it just takes an
additional line to define.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
In our linker script we open code the list of text sections, because we
need to include the __ftr_alt sections, which are arch-specific.
This means we can't use TEXT_TEXT as defined in vmlinux.lds.h, and so we
don't have the MEM_KEEP() logic for memory hotplug sections.
If we build the kernel with the gold linker, and with CONFIG_MEMORY_HOTPLUG=y,
we see that functions marked __meminit can end up outside of the
_stext/_etext range, and also outside of _sinittext/_einittext, eg:
c000000000000000 T _stext
c0000000009e0000 A _etext
c0000000009e3f18 T hash__vmemmap_create_mapping
c000000000ca0000 T _sinittext
c000000000d00844 T _einittext
This causes them to not be recognised as text by is_kernel_text(), and
prevents them being patched by jump_label (and presumably ftrace/kprobes
etc.).
Fix it by adding MEM_KEEP() directives, mirroring what TEXT_TEXT does.
This isn't a problem when CONFIG_MEMORY_HOTPLUG=n, because we use the
standard INIT_TEXT_SECTION() and EXIT_TEXT macros from vmlinux.lds.h.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Tested-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
It is seldom used in the kernel code and can be easily replaced by
either RELOCATABLE or PPC32. So there is no reason to keep a separate
kernel option for this.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
KASAN needs to know whether the allocation happens in an IRQ handler.
This lets us strip everything below the IRQ entry point to reduce the
number of unique stack traces needed to be stored.
Move the definition of __irq_entry to <linux/interrupt.h> so that the
users don't need to pull in <linux/ftrace.h>. Also introduce the
__softirq_entry macro which is similar to __irq_entry, but puts the
corresponding functions to the .softirqentry.text section.
Signed-off-by: Alexander Potapenko <glider@google.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
.exit.text is discarded at run time and there are some references from
that to .exit.data, so we need to discard .exit.data at run time as well.
Fixes these errors:
`.exit.data' referenced in section `.exit.text' of drivers/built-in.o: defined in discarded section `.exit.data' of drivers/built-in.o
`.exit.data' referenced in section `.exit.text' of drivers/built-in.o: defined in discarded section `.exit.data' of drivers/built-in.o
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Recent toolchains force the TOC to be 256 byte aligned. We need
to enforce this alignment in our linker script, otherwise pointers
to our TOC variables (__toc_start, __prom_init_toc_start) could
be incorrect.
If they are bad, we die a few hundred instructions into boot.
Cc: stable@vger.kernel.org
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Module CRCs are implemented as absolute symbols that get resolved by
a linker script. We build an intermediate .o that contains an
unresolved symbol for each CRC. genksysms parses this .o, calculates
the CRCs and writes a linker script that "resolves" the symbols to
the calculated CRC.
Unfortunately the ppc64 relocatable kernel sees these CRCs as symbols
that need relocating and relocates them at boot. Commit d4703aef
(module: handle ppc64 relocating kcrctabs when CONFIG_RELOCATABLE=y)
added a hook to reverse the bogus relocations. Part of this patch
created a symbol at 0x0:
# head -2 /proc/kallsyms
0000000000000000 T reloc_start
c000000000000000 T .__start
This reloc_start symbol is causing lots of confusion to perf. It
thinks reloc_start is a massive function that stretches from 0x0 to
0xc000000000000000 and we get various cryptic errors out of perf,
including:
problem incrementing symbol count, skipping event
This patch removes the reloc_start linker script label and instead
defines it as PHYSICAL_START. We also need to wrap it with
CONFIG_PPC64 because the ppc32 kernel can set a non zero
PHYSICAL_START at compile time and we wouldn't want to subtract
it from the CRCs in that case.
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The ppc64 kernel can get loaded at any address which means
our very early init code in prom_init.c must be relocatable. We do
this with a pretty nasty RELOC() macro that we wrap accesses of
variables with. It is very fragile and sometimes we forget to add a
RELOC() to an uncommon path or sometimes a compiler change breaks it.
32bit has a much more elegant solution where we build prom_init.c
with -mrelocatable and then process the relocations manually.
Unfortunately we can't do the equivalent on 64bit and we would
have to build the entire kernel relocatable (-pie), resulting in a
large increase in kernel footprint (megabytes of relocation data).
The relocation data will be marked __initdata but it still creates
more pressure on our already tight memory layout at boot.
Alan Modra pointed out that the 64bit ABI is relocatable even
if we don't build with -pie, we just need to relocate the TOC.
This patch implements that idea and relocates the TOC entries of
prom_init.c. An added bonus is there are very few relocations to
process which helps keep boot times on simulators down.
gcc does not put 64bit integer constants into the TOC but to be
safe we may want a build time script which passes through the
prom_init.c TOC entries to make sure everything looks reasonable.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This removes the various bits of assembly in the kernel entry,
exception handling and SLB management code that were specific
to running under the legacy iSeries hypervisor which is no
longer supported.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The following patch implements the dynamic relocation processing for
PPC32 kernel. relocate() accepts the target virtual address and relocates
the kernel image to the same.
Currently the following relocation types are handled :
R_PPC_RELATIVE
R_PPC_ADDR16_LO
R_PPC_ADDR16_HI
R_PPC_ADDR16_HA
The last 3 relocations in the above list depends on value of Symbol indexed
whose index is encoded in the Relocation entry. Hence we need the Symbol
Table for processing such relocations.
Note: The GNU ld for ppc32 produces buggy relocations for relocation types
that depend on symbols. The value of the symbols with STB_LOCAL scope
should be assumed to be zero. - Alan Modra
Signed-off-by: Suzuki K. Poulose <suzuki@in.ibm.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@linux.vnet.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Alan Modra <amodra@au1.ibm.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: linuxppc-dev <linuxppc-dev@lists.ozlabs.org>
Signed-off-by: Josh Boyer <jwboyer@gmail.com>
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
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>
Signed-off-by: Tim Abbott <tabbott@ksplice.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: Tim Abbott <tabbott@ksplice.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: Tim Abbott <tabbott@ksplice.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
powerpc applies relocations to the kcrctab. They're absolute symbols,
but it's not completely unreasonable: other archs may too, but the
relocation is often 0.
http://lists.ozlabs.org/pipermail/linuxppc-dev/2009-November/077972.html
Inspired-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Tested-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Paul Mackerras <paulus@samba.org>
We need to align before the output section. Having the align inside
the output section causes the linker to put some filler in there,
which makes it a non-empty section, but this section isn't assigned to
a segment so you get a warning from the linker.
Signed-off-by: Sean MacLennan <smaclennan@pikatech.com>
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (134 commits)
powerpc/nvram: Enable use Generic NVRAM driver for different size chips
powerpc/iseries: Fix oops reading from /proc/iSeries/mf/*/cmdline
powerpc/ps3: Workaround for flash memory I/O error
powerpc/booke: Don't set DABR on 64-bit BookE, use DAC1 instead
powerpc/perf_counters: Reduce stack usage of power_check_constraints
powerpc: Fix bug where perf_counters breaks oprofile
powerpc/85xx: Fix SMP compile error and allow NULL for smp_ops
powerpc/irq: Improve nanodoc
powerpc: Fix some late PowerMac G5 with PCIe ATI graphics
powerpc/fsl-booke: Use HW PTE format if CONFIG_PTE_64BIT
powerpc/book3e: Add missing page sizes
powerpc/pseries: Fix to handle slb resize across migration
powerpc/powermac: Thermal control turns system off too eagerly
powerpc/pci: Merge ppc32 and ppc64 versions of phb_scan()
powerpc/405ex: support cuImage via included dtb
powerpc/405ex: provide necessary fixup function to support cuImage
powerpc/40x: Add support for the ESTeem 195E (PPC405EP) SBC
powerpc/44x: Add Eiger AMCC (AppliedMicro) PPC460SX evaluation board support.
powerpc/44x: Update Arches defconfig
powerpc/44x: Update Arches dts
...
Fix up conflicts in drivers/char/agp/uninorth-agp.c
Currently _edata does not include several data sections, this causes
the kernel's report of memory usage at boot to not match reality, and
also prevents kmemleak from working - because it scan between _sdata
and _edata for pointers to allocated memory.
This mirrors a similar change made recently to the x86 linker script.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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>
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>
I don't think anything guarantees that the objects in data.page_aligned
are a multiple of PAGE_SIZE, thus the section may end on any boundary.
So the following section, .data.cacheline_aligned needs an explicit
alignment.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Commit edada399 broke the build on 64-bit powerpc because it moved the
__ftr_alt_* sections of a file away from the .text section, causing
link failures due to relative conditional branch targets being too far
away from the branch instructions. This happens on pretty much all
64-bit powerpc configs.
This change reverts commit edada399 while preserving the update from
the *.refok sections to .ref.text that has happened since.
Signed-off-by: Tim Abbott <tabbott@mit.edu>
Requested-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rather than adding .ref.text to the powerpc linker script so that we
can use __REF on the powerpc architecture, it seems simpler to switch
to using the generic TEXT_TEXT macro.
Signed-off-by: Tim Abbott <tabbott@mit.edu>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This has the consequence of changing the section name use for head
code from ".text.head" to ".head.text". Since this commit changes all
users in the architecture, this change should be harmless.
Signed-off-by: Tim Abbott <tabbott@mit.edu>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Impact: __per_cpu_load available on all SMP capable archs
Percpu now requires three symbols to be defined - __per_cpu_load,
__per_cpu_start and __per_cpu_end. There were three archs which
didn't have it. Update them as follows.
* powerpc: can use generic PERCPU() macro. Compile tested for
powerpc32, compile/boot tested for powerpc64.
* ia64: can use generic PERCPU_VADDR() macro. __phys_per_cpu_start is
identical to __per_cpu_load. Compile tested and symbol table looks
identical after the change except for the additional __per_cpu_load.
* arm: added explicit __per_cpu_load definition. Currently uses
unified .init output section so can't use the generic macro. Dunno
whether the unified .init ouput section is required by arch
peculiarity so I left it alone. Please break it up and use PERCPU()
if possible.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Pat Gefre <pfg@sgi.com>
Cc: Russell King <rmk@arm.linux.org.uk>
This is a port of the function graph tracer that was written by
Frederic Weisbecker for the x86.
This only works for PPC64 at the moment and only for static tracing.
PPC32 and dynamic function graph tracing support will come later.
The trace produces a visual calling of functions:
# tracer: function_graph
#
# CPU DURATION FUNCTION CALLS
# | | | | | | |
0) 2.224 us | }
0) ! 271.024 us | }
0) ! 320.080 us | }
0) ! 324.656 us | }
0) ! 329.136 us | }
0) | .put_prev_task_fair() {
0) | .update_curr() {
0) 2.240 us | .update_min_vruntime();
0) 6.512 us | }
0) 2.528 us | .__enqueue_entity();
0) + 15.536 us | }
0) | .pick_next_task_fair() {
0) 2.032 us | .__pick_next_entity();
0) 2.064 us | .__clear_buddies();
0) | .set_next_entity() {
0) 2.672 us | .__dequeue_entity();
0) 6.864 us | }
Geoff Lavand tested on PS3.
Tested-by: Geoff Levand <geoffrey.levand@am.sony.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
arm, arm/mach-integrator and powerpc were missing
.data.percpu.page_aligned in their percpu output section definitions.
Add it.
Signed-off-by: Tejun Heo <tj@kernel.org>
We are declaring the dummy section (used to work around a binutils
bug) as PT_NOTE, but we don't have enough bytes for it to be a valid
note header, and kexec userspace complains:
Warning: Elf Note name is not null terminated
Warning: append= option is not passed. Using the first kernel root partition
Warning: Elf Note name is not null terminated
Instead of using the arbitray value 0xf177 (aka "fill"), declare a
no-name no-description note of type 0.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We're soon running out of CPU features and I need to add some new
ones for various MMU related bits, so this patch separates the MMU
features from the CPU features. I moved over the 32-bit MMU related
ones, added base features for MMU type families, but didn't move
over any 64-bit only feature yet.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This reverts commit 91a0030295, plus
commit 0dcd440120 ("powerpc: Revert CHRP
boot wrapper to real-base = 12MB on 32-bit") which depended on it.
Commit 91a00302 was causing NVRAM corruption on some pSeries machines,
for as-yet unknown reasons, so this reverts it until the cause is
identified.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Commit 549e8152de ("powerpc: Make the
64-bit kernel as a position-independent executable") added lines to
vmlinux.lds.S to add the extra sections needed to implement a
relocatable kernel. However, those lines seem to trigger a bug in
older versions of GNU ld (such as 2.16.1) when building a
non-relocatable kernel. Since ld 2.16.1 is still a popular choice for
cross-toolchains, this adds an #ifdef to vmlinux.lds.S so the added
lines are only included when building a relocatable kernel.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Commit 9b09c6d909 ("powerpc: Change the
default link address for pSeries zImage kernels") changed the
real-base value in the CHRP note added by the addnote program from
12MB to 32MB to give more space for Open Firmware to load the zImage.
(The real-base value says where we want OF to position itself in
memory.) However, this change was ineffective on most pSeries
machines, because the RPA note added by addnote has the "ignore me"
flag set to 1. This was intended to tell OF to ignore just the RPA
note, but has the side effect of also making OF ignore the CHRP note
(at least on most pSeries machines).
To solve this we have to set the "ignore me" flag to 0 in the RPA
note. (We can't just omit the RPA note because that is equivalent to
having an RPA note with default values, and the default values are not
what we want.) However, then we have to make sure the values in the
zImage's RPA note match up with the values that the kernel supplies
later in prom_init.c with either the ibm,client-architecture-support
call or the process-elf-header call in prom_send_capabilities().
So this sets the "ignore me" flag in the RPA note in addnote to 0, and
adjusts the RPA note values in addnote.c and in prom_init.c to be
consistent with each other and with the values in ibm_architecture_vec.
However, since the wrapper is independent of the kernel, this doesn't
ensure that the notes will stay consistent. To ensure that, this adds
code to addnote.c so that it can extract the kernel's RPA note from
the kernel binary and put that in the zImage. To that end, we put the
kernel's fake ELF header (which contains the kernel's RPA note) into
its own section, and arrange for wrapper to pull out that section with
objcopy and pass it to addnote, which then extracts the RPA note from
it and transfers it to the zImage.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This implements CONFIG_RELOCATABLE for 64-bit by making the kernel as
a position-independent executable (PIE) when it is set. This involves
processing the dynamic relocations in the image in the early stages of
booting, even if the kernel is being run at the address it is linked at,
since the linker does not necessarily fill in words in the image for
which there are dynamic relocations. (In fact the linker does fill in
such words for 64-bit executables, though not for 32-bit executables,
so in principle we could avoid calling relocate() entirely when we're
running a 64-bit kernel at the linked address.)
The dynamic relocations are processed by a new function relocate(addr),
where the addr parameter is the virtual address where the image will be
run. In fact we call it twice; once before calling prom_init, and again
when starting the main kernel. This means that reloc_offset() returns
0 in prom_init (since it has been relocated to the address it is running
at), which necessitated a few adjustments.
This also changes __va and __pa to use an equivalent definition that is
simpler. With the relocatable kernel, PAGE_OFFSET and MEMORY_START are
constants (for 64-bit) whereas PHYSICAL_START is a variable (and
KERNELBASE ideally should be too, but isn't yet).
With this, relocatable kernels still copy themselves down to physical
address 0 and run there.
Signed-off-by: Paul Mackerras <paulus@samba.org>
This makes core_kernel_text() (and therefore kernel_text_address())
return the correct result. Currently all the __devinit routines (at
least) will not be considered to be kernel text.
This is just a quick fix for 2.6.27 - hopefully we will be able to fix
this better in 2.6.28.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
