summaryrefslogtreecommitdiff
path: root/arch/arm/kernel/vmlinux.lds.S
AgeCommit message (Collapse)Author
2015-04-16Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "Here are the core arm64 updates for 4.1. Highlights include a significant rework to head.S (allowing us to boot on machines with physical memory at a really high address), an AES performance boost on Cortex-A57 and the ability to run a 32-bit userspace with 64k pages (although this requires said userspace to be built with a recent binutils). The head.S rework spilt over into KVM, so there are some changes under arch/arm/ which have been acked by Marc Zyngier (KVM co-maintainer). In particular, the linker script changes caused us some issues in -next, so there are a few merge commits where we had to apply fixes on top of a stable branch. Other changes include: - AES performance boost for Cortex-A57 - AArch32 (compat) userspace with 64k pages - Cortex-A53 erratum workaround for #845719 - defconfig updates (new platforms, PCI, ...)" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (39 commits) arm64: fix midr range for Cortex-A57 erratum 832075 arm64: errata: add workaround for cortex-a53 erratum #845719 arm64: Use bool function return values of true/false not 1/0 arm64: defconfig: updates for 4.1 arm64: Extract feature parsing code from cpu_errata.c arm64: alternative: Allow immediate branch as alternative instruction arm64: insn: Add aarch64_insn_decode_immediate ARM: kvm: round HYP section to page size instead of log2 upper bound ARM: kvm: assert on HYP section boundaries not actual code size arm64: head.S: ensure idmap_t0sz is visible arm64: pmu: add support for interrupt-affinity property dt: pmu: extend ARM PMU binding to allow for explicit interrupt affinity arm64: head.S: ensure visibility of page tables arm64: KVM: use ID map with increased VA range if required arm64: mm: increase VA range of identity map ARM: kvm: implement replacement for ld's LOG2CEIL() arm64: proc: remove unused cpu_get_pgd macro arm64: enforce x1|x2|x3 == 0 upon kernel entry as per boot protocol arm64: remove __calc_phys_offset arm64: merge __enable_mmu and __turn_mmu_on ...
2015-03-29ARM: 8322/1: keep .text and .fixup regions closer togetherArd Biesheuvel
This moves all fixup snippets to the .text.fixup section, which is a special section that gets emitted along with the .text section for each input object file, i.e., the snippets are kept much closer to the code they refer to, which helps prevent linker failure on large kernels. Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-03-28ARM: 8317/1: move the .idmap.text section closer to .head.textArd Biesheuvel
This moves the .idmap.text section closer to .head.text, so that relative branches are less likely to go out of range if the kernel text gets bigger. Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-03-27ARM: kvm: round HYP section to page size instead of log2 upper boundArd Biesheuvel
Older binutils do not support expressions involving the values of external symbols so just round up the HYP region to the page size. Tested-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> [will: when will this ever end?!] Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-25ARM: kvm: assert on HYP section boundaries not actual code sizeArd Biesheuvel
Using ASSERT() with an expression that involves a symbol that is only supplied through a PROVIDE() definition in the linker script itself is apparently not supported by some older versions of binutils. So instead, rewrite the expression so that only the section boundaries __hyp_idmap_text_start and __hyp_idmap_text_end are used. Note that this reverts the fix in 06f75a1f6200 ("ARM, arm64: kvm: get rid of the bounce page") for the ASSERT() being triggered erroneously when unrelated linker emitted veneers happen to end up in the HYP idmap region. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-23ARM: kvm: implement replacement for ld's LOG2CEIL()Ard Biesheuvel
Commit 06f75a1f6200 ("ARM, arm64: kvm: get rid of the bounce page") uses ld's builtin function LOG2CEIL() to align the KVM init code to a log2 upper bound of its size. However, this function turns out to be a fairly recent addition to binutils, which breaks the build for older toolchains. So instead, implement a replacement LOG2_ROUNDUP() using the C preprocessor. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-19ARM, arm64: kvm: get rid of the bounce pageArd Biesheuvel
The HYP init bounce page is a runtime construct that ensures that the HYP init code does not cross a page boundary. However, this is something we can do perfectly well at build time, by aligning the code appropriately. For arm64, we just align to 4 KB, and enforce that the code size is less than 4 KB, regardless of the chosen page size. For ARM, the whole code is less than 256 bytes, so we tweak the linker script to align at a power of 2 upper bound of the code size Note that this also fixes a benign off-by-one error in the original bounce page code, where a bounce page would be allocated unnecessarily if the code was exactly 1 page in size. On ARM, it also fixes an issue with very large kernels reported by Arnd Bergmann, where stub sections with linker emitted veneers could erroneously trigger the size/alignment ASSERT() in the linker script. Tested-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-03Merge tag 'ronx-next' of ↵Russell King
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux into devel-stable generic fixmaps ARM support for CONFIG_DEBUG_RODATA
2014-10-16ARM: mm: allow text and rodata sections to be read-onlyKees Cook
This introduces CONFIG_DEBUG_RODATA, making kernel text and rodata read-only. Additionally, this splits rodata from text so that rodata can also be NX, which may lead to wasted memory when aligning to SECTION_SIZE. The read-only areas are made writable during ftrace updates and kexec. Signed-off-by: Kees Cook <keescook@chromium.org> Tested-by: Laura Abbott <lauraa@codeaurora.org> Acked-by: Nicolas Pitre <nico@linaro.org>
2014-10-16ARM: mm: allow non-text sections to be non-executableKees Cook
Adds CONFIG_ARM_KERNMEM_PERMS to separate the kernel memory regions into section-sized areas that can have different permisions. Performs the NX permission changes during free_initmem, so that init memory can be reclaimed. This uses section size instead of PMD size to reduce memory lost to padding on non-LPAE systems. Based on work by Brad Spengler, Larry Bassel, and Laura Abbott. Signed-off-by: Kees Cook <keescook@chromium.org> Tested-by: Laura Abbott <lauraa@codeaurora.org> Acked-by: Nicolas Pitre <nico@linaro.org>
2014-10-02ARM: 8168/1: extend __init_end to a page align addressYalin Wang
This patch changes the __init_end address to a page align address, so that free_initmem() can free the whole .init section, because if the end address is not page aligned, it will round down to a page align address, then the tail unligned page will not be freed. Signed-off-by: wang <yalin.wang2010@gmail.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18ARM: 8088/1: vmlinux.lds.S: drop redundant .commentMark Rutland
Commit 78d7530ac3 ("ARM: Clean up linker script using new linker script macros.") modified the arm kernel linker script to use the STABS_DEBUG macro, but left a .comment section definition. As STABS_DEBUG defines the .comment section in an identical way, the second section definition is redundant and can be removed. This patch removes the redundant .comment section definition. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-07-31ARM: use linker magic for vectors and vector stubsRussell King
Use linker magic to create the vectors and vector stubs: we can tell the linker to place them at an appropriate VMA, but keep the LMA within the kernel. This gets rid of some unnecessary symbol manipulation, and have the linker calculate the relocations appropriately. Cc: <stable@vger.kernel.org> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-06-03Finally eradicate CONFIG_HOTPLUGStephen Rothwell
Ever since commit 45f035ab9b8f ("CONFIG_HOTPLUG should be always on"), it has been basically impossible to build a kernel with CONFIG_HOTPLUG turned off. Remove all the remaining references to it. Cc: Russell King <linux@arm.linux.org.uk> Cc: Doug Thompson <dougthompson@xmission.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com> Acked-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-28ARM: KVM: enforce maximum size for identity mapped codeMarc Zyngier
We're about to move to an init procedure where we rely on the fact that the init code fits in a single page. Make sure we align the idmap text on a vector alignment, and that the code is not bigger than a single page. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <cdall@cs.columbia.edu>
2013-01-23ARM: Section based HYP idmapChristoffer Dall
Add a method (hyp_idmap_setup) to populate a hyp pgd with an identity mapping of the code contained in the .hyp.idmap.text section. Offer a method to drop this identity mapping through hyp_idmap_teardown. Make all the above depend on CONFIG_ARM_VIRT_EXT and CONFIG_ARM_LPAE. Reviewed-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
2012-12-16ARM: 7605/1: vmlinux.lds: Move .notes section next to the rodataPawel Moll
The .notes, being read-only data by nature, were placed between read-write .data and .bss. This was harmful in case of the XIP kernel, as being placed in the RAM range, most likely far from the ROM address, was inflating the XIP images. Moving the .notes at the end of the read-only section (consisting of .text, .rodata and unwind info) fixes the problem. Reported-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Pawel Moll <pawel.moll@arm.com> Tested-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04ARM: 7568/1: Sort exception table at compile timeStephen Boyd
Add the ARM machine identifier to sortextable and select the config option so that we can sort the exception table at compile time. sortextable relies on a section named __ex_table existing in the vmlinux, but ARM's linker script places the exception table in the data section. Give the exception table its own section so that sortextable can find it. This allows us to skip the sorting step during boot. Cc: David Daney <david.daney@cavium.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Tested-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-06-22ARM: 7428/1: Prevent KALLSYM size mismatch on ARM.David Brown
ARM builds seem to be plagued by an occasional build error: Inconsistent kallsyms data This is a bug - please report about it Try "make KALLSYMS_EXTRA_PASS=1" as a workaround The problem has to do with alignment of some sections by the linker. The kallsyms data is built in two passes by first linking the kernel without it, and then linking the kernel again with the symbols included. Normally, this just shifts the symbols, without changing their order, and the compression used by the kallsyms gives the same result. On non SMP, the per CPU data is empty. Depending on the where the alignment ends up, it can come out as either: +-------------------+ | last text segment | +-------------------+ /* padding */ +-------------------+ <- L1_CACHE_BYTES alignemnt | per cpu (empty) | +-------------------+ __per_cpu_end: /* padding */ __data_loc: +-------------------+ <- THREAD_SIZE alignment | data | +-------------------+ or +-------------------+ | last text segment | +-------------------+ /* padding */ +-------------------+ <- L1_CACHE_BYTES alignemnt | per cpu (empty) | +-------------------+ __per_cpu_end: /* no padding */ __data_loc: +-------------------+ <- THREAD_SIZE alignment | data | +-------------------+ if the alignment satisfies both. Because symbols that have the same address are sorted by 'nm -n', the second case will be in a different order than the first case. This changes the compression, changing the size of the kallsym data, causing the build failure. The KALLSYMS_EXTRA_PASS=1 workaround usually works, but it is still possible to have the alignment change between the second and third pass. It's probably even possible for it to never reach a fixedpoint. The problem only occurs on non-SMP, when the per-cpu data is empty, and when the data segment has alignment (and immediately follows the text segments). Fix this by only including the per_cpu section on SMP, when it is not empty. Signed-off-by: David Brown <davidb@codeaurora.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-02-09ARM: 7320/1: Fix proc_info table alignmentMarc Zyngier
With an admittedly exotic choice of configuration options (CC_OPTIMIZE_FOR_SIZE, THUMB2, some other size-minimizing ones) and compiler, the proc_info table can end up being misaligned, and the kernel being unbootable (Error: unrecognized/unsupported processor variant). Forcing the alignement to 4 bytes in the linker script fixes the issue. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-01-23ARM: 7290/1: vmlinux.lds.S: align the exception fixup table to a 4-byte boundaryWill Deacon
The exception fixup table is currently aligned to a 32-byte boundary. Whilst this won't cause any problems, the exception_table_entry structures contain only a pair of unsigned longs, so 4-byte alignment is all that is required. If the table was walked from start to end, cacheline alignment may bring some performance benefits, but since a binary search is used, the access pattern is random and will not benefit from a stricter alignment. Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-01-23ARM: 7289/1: vmlinux.lds.S: do not hardcode cacheline size as 32 bytesWill Deacon
The linker script assumes a cacheline size of 32 bytes when aligning the .data..cacheline_aligned and .data..percpu sections. This patch updates the script to use L1_CACHE_BYTES, which should be set to 64 on platforms that require it. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-12-06ARM: idmap: populate identity map pgd at init time using .init.textWill Deacon
When disabling and re-enabling the MMU, it is necessary to take out an identity mapping for the code that manipulates the SCTLR in order to avoid it disappearing from under our feet. This is useful when soft rebooting and returning from CPU suspend. This patch allocates a set of page tables during boot and populates them with an identity mapping for the .idmap.text section. This means that users of the identity map do not need to manage their own pgd and can instead annotate their functions with __idmap or, in the case of assembly code, place them in the correct section. Acked-by: Dave Martin <dave.martin@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2011-10-25Merge branch 'misc' into for-linusRussell King
Conflicts: arch/arm/mach-integrator/integrator_ap.c
2011-10-17ARM: 7017/1: Use generic BUG() handlerSimon Glass
ARM uses its own BUG() handler which makes its output slightly different from other archtectures. One of the problems is that the ARM implementation doesn't report the function with the BUG() in it, but always reports the PC being in __bug(). The generic implementation doesn't have this problem. Currently we get something like: kernel BUG at fs/proc/breakme.c:35! Unable to handle kernel NULL pointer dereference at virtual address 00000000 ... PC is at __bug+0x20/0x2c With this patch it displays: kernel BUG at fs/proc/breakme.c:35! Internal error: Oops - undefined instruction: 0 [#1] PREEMPT SMP ... PC is at write_breakme+0xd0/0x1b4 This implementation uses an undefined instruction to implement BUG, and sets up a bug table containing the relevant information. Many versions of gcc do not support %c properly for ARM (inserting a # when they shouldn't) so we work around this using distasteful macro magic. v1: Initial version to replace existing ARM BUG() implementation with something more similar to other architectures. v2: Add Thumb support, remove backtrace whitespace output changes. Change to use macros instead of requiring the asm %d flag to work (thanks to Dave Martin <dave.martin@linaro.org>) v3: Remove old BUG() implementation in favor of this one. Remove the Backtrace: message (will submit this separately). Use ARM_EXIT_KEEP() so that some architectures can dump exit text at link time thanks to Stephen Boyd <sboyd@codeaurora.org> (although since we always define GENERIC_BUG this might be academic.) Rebase to linux-2.6.git master. v4: Allow BUGS in modules (these were not reported correctly in v3) (thanks to Stephen Boyd <sboyd@codeaurora.org> for suggesting that.) Remove __bug() as this is no longer needed. v5: Add %progbits as the section flags. Signed-off-by: Simon Glass <sjg@chromium.org> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Tested-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-09-20ARM: fix vmlinux.lds.S discarding sectionsRussell King
We are seeing linker errors caused by sections being discarded, despite the linker script trying to keep them. The result is (eg): `.exit.text' referenced in section `.alt.smp.init' of drivers/built-in.o: defined in discarded section `.exit.text' of drivers/built-in.o `.exit.text' referenced in section `.alt.smp.init' of net/built-in.o: defined in discarded section `.exit.text' of net/built-in.o This is the relevent part of the linker script (reformatted to make it clearer): | SECTIONS | { | /* | * unwind exit sections must be discarded before the rest of the | * unwind sections get included. | */ | /DISCARD/ : { | *(.ARM.exidx.exit.text) | *(.ARM.extab.exit.text) | } | ... | .exit.text : { | *(.exit.text) | *(.memexit.text) | } | ... | /DISCARD/ : { | *(.exit.text) | *(.memexit.text) | *(.exit.data) | *(.memexit.data) | *(.memexit.rodata) | *(.exitcall.exit) | *(.discard) | *(.discard.*) | } | } Now, this is what the linker manual says about discarded output sections: | The special output section name `/DISCARD/' may be used to discard | input sections. Any input sections which are assigned to an output | section named `/DISCARD/' are not included in the output file. No questions, no exceptions. It doesn't say "unless they are listed before the /DISCARD/ section." Now, this is what asn-generic/vmlinux.lds.S says: | /* | * Default discarded sections. | * | * Some archs want to discard exit text/data at runtime rather than | * link time due to cross-section references such as alt instructions, | * bug table, eh_frame, etc. DISCARDS must be the last of output | * section definitions so that such archs put those in earlier section | * definitions. | */ And guess what - the list _always_ includes .exit.text etc. Now, what's actually happening is that the linker is reading the script, and it finds the first /DISCARD/ output section at the beginning of the script. It continues reading the script, and finds the 'DISCARD' macro at the end, which having been postprocessed results in another /DISCARD/ output section. As the linker already contains the earlier /DISCARD/ output section, it adds it to that existing section, so it effectively is placed at the start. This can be seen by using the -M option to ld: | Linker script and memory map | | 0xc037c080 jiffies = jiffies_64 | | /DISCARD/ | *(.ARM.exidx.exit.text) | *(.ARM.extab.exit.text) | *(.exit.text) | *(.memexit.text) | *(.exit.data) | *(.memexit.data) | *(.memexit.rodata) | *(.exitcall.exit) | *(.discard) | *(.discard.*) | | 0xc0008000 . = 0xc0008000 | | .head.text 0xc0008000 0x1d0 | 0xc0008000 _text = . | *(.head.text) | .head.text 0xc0008000 0x1d0 arch/arm/kernel/head.o | 0xc0008000 stext | | .text 0xc0008200 0x2d78d0 | 0xc0008200 _stext = . | 0xc0008200 __exception_text_start = . | *(.exception.text) | .exception.text | ... As you can see, all the discarded sections are grouped together - and as a result of it being the first output section, they all appear before any other section. The result is that not only is the unwind information discarded (as intended), but also the .exit.text, despite us wanting to have the .exit.text preserved. We can't move the unwind information elsewhere, because it'll then be included even when we do actually discard the .exit.text (and similar) sections. So, work around this by avoiding the generic DISCARDS macro, and instead conditionalize the sections to be discarded ourselves. This avoids the ambiguity in how the linker assigns input sections to output sections, making our script less dependent on undocumented linker behaviour. Reported-by: Rob Herring <robherring2@gmail.com> Tested-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-07ARM: vmlinux.lds: use _text and _stext the same way as x86Russell King
x86 uses _text to mark the start of the kernel image including the head text, and _stext to mark the start of the .text section. Change our vmlinux.lds to conform. An audit of the places which use _stext and _text in arch/arm indicates no users of either symbol are impacted by this change. It does mean a slight change to /proc/iomem output. Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Tested-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-07ARM: vmlinux.lds: move init sections between text and data sectionsRussell King
Place the init sections between the text and data sections. This means all code is grouped together at the beginning of the kernel image, and all data is at the end of the image. This avoids problems with the 24-bit branch instruction relocations becoming invalid with large initramfs images. Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Tested-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-07ARM: vmlinux.lds: remove .rodata/.rodata1 from main .text segmentRussell King
RODATA() already handles these sections, so allow it to take care of them for us. Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Tested-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-07ARM: vmlinux.lds: rearrange .init output sectionRussell King
Keep the various linker tables as separate output sections rather than combining them together into one big .init section. This makes the 'vmlinux' easier to see what is placed where. Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Tested-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-07ARM: vmlinux.lds: move discarded sections to beginningRussell King
Rather than scattering the discarded sections throughout the linker file, move them to the start. Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Tested-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-03-24percpu: Always align percpu output section to PAGE_SIZETejun Heo
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
2011-03-16Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (91 commits) ARM: 6806/1: irq: introduce entry and exit functions for chained handlers ARM: 6781/1: Thumb-2: Work around buggy Thumb-2 short branch relocations in gas ARM: 6747/1: P2V: Thumb2 support ARM: 6798/1: aout-core: zero thread debug registers in a.out core dump ARM: 6796/1: Footbridge: Fix I/O mappings for NOMMU mode ARM: 6784/1: errata: no automatic Store Buffer drain on Cortex-A9 ARM: 6772/1: errata: possible fault MMU translations following an ASID switch ARM: 6776/1: mach-ux500: activate fix for errata 753970 ARM: 6794/1: SPEAr: Append UL to device address macros. ARM: 6793/1: SPEAr: Remove unused *_SIZE macros from spear*.h files ARM: 6792/1: SPEAr: Replace SIZE macro's with SZ_4K macros ARM: 6791/1: SPEAr3xx: Declare device structures after shirq code ARM: 6790/1: SPEAr: Clock Framework: Rename usbd clock and align apb_clk entry ARM: 6789/1: SPEAr3xx: Rename sdio to sdhci ARM: 6788/1: SPEAr: Include mach/hardware.h instead of mach/spear.h ARM: 6787/1: SPEAr: Reorder #includes in .h & .c files. ARM: 6681/1: SPEAr: add debugfs support to clk API ARM: 6703/1: SPEAr: update clk API support ARM: 6679/1: SPEAr: make clk API functions more generic ARM: 6737/1: SPEAr: formalized timer support ...
2011-03-16Merge branch 'p2v' into develRussell King
Conflicts: arch/arm/kernel/module.c arch/arm/mach-s5pv210/sleep.S
2011-03-16Merge branch 'for-2.6.39' of ↵Linus Torvalds
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")
2011-02-21ARM: Keep exit text/data around for SMP_ON_UPRussell King
When SMP_ON_UP is used and the spinlocks are inlined, we end up with inline spinlocks in the exit code, with references from the SMP alternatives section to the exit sections. This causes link time errors. Avoid this by placing the exit sections in the init-discarded region. Cc: <stable@kernel.org> Tested-by: Dave Martin <dave.martin@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-21ARM: 6740/1: Place correctly notes section in the linker scriptPawel Moll
Commit 18991197b4b588255ccabf472ebc84db7b66a19c added --build-id linker option when toolchain supports it. ARM one does, but for some reason places the section at 0 when linker script doesn't mention it explicitly. The 1e621a8e3752367d4aae78a8ab00a18fb2793f34 worked around the problem removing this section from binary image with explicit objcopy options, but it still exists in vmlinux, confusing tools like debuggers and perf. This problem was discussed here: http://lists.infradead.org/pipermail/linux-arm-kernel/2010-May/015994.html http://lists.infradead.org/pipermail/linux-arm-kernel/2010-May/015994.html but the proposed changes to the linker script were substantial. This patch simply places NOTES (36 bytes long, at least when compiled with CodeSourcery toolchain) between data and bss, which seem to be the right place (and suggested by the sample linker script in include/asm-generic/vmlinux.lds.h). It is enough to place it correctly in vmlinux (so debuggers are happy): Section Headers: [11] .data PROGBITS c07ce000 7ce000 020fc0 00 WA 0 0 32 [12] .notes NOTE c07eefc0 7eefc0 000024 00 AX 0 0 4 [13] .bss NOBITS c07ef000 7eefe4 01e628 00 WA 0 0 32 Program Headers: LOAD 0x008000 0xc0008000 0xc0008000 0x7e6fe4 0x805628 RWE 0x8000 NOTE 0x7eefc0 0xc07eefc0 0xc07eefc0 0x00024 0x00024 R E 0x4 Section to Segment mapping: Segment Sections... 00 <...> .data .notes .bss 01 .notes and to get it exposed as /sys/kernel/notes used by perf tools. Signed-off-by: Pawel Moll <pawel.moll@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-17ARM: P2V: introduce phys_to_virt/virt_to_phys runtime patchingRussell King
This idea came from Nicolas, Eric Miao produced an initial version, which was then rewritten into this. Patch the physical to virtual translations at runtime. As we modify the code, this makes it incompatible with XIP kernels, but allows us to achieve this with minimal loss of performance. As many translations are of the form: physical = virtual + (PHYS_OFFSET - PAGE_OFFSET) virtual = physical - (PHYS_OFFSET - PAGE_OFFSET) we generate an 'add' instruction for __virt_to_phys(), and a 'sub' instruction for __phys_to_virt(). We calculate at run time (PHYS_OFFSET - PAGE_OFFSET) by comparing the address prior to MMU initialization with where it should be once the MMU has been initialized, and place this constant into the above add/sub instructions. Once we have (PHYS_OFFSET - PAGE_OFFSET), we can calculate the real PHYS_OFFSET as PAGE_OFFSET is a build-time constant, and save this for the C-mode PHYS_OFFSET variable definition to use. At present, we are unable to support Realview with Sparsemem enabled as this uses a complex mapping function, and MSM as this requires a constant which will not fit in our math instruction. Add a module version magic string for this feature to prevent incompatible modules being loaded. Tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org> Tested-by: Nicolas Pitre <nicolas.pitre@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-25percpu: align percpu readmostly subsection to cachelineTejun Heo
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>
2011-01-06Merge branch 'misc' into develRussell King
Conflicts: arch/arm/Kconfig arch/arm/common/Makefile arch/arm/kernel/Makefile arch/arm/kernel/smp.c
2010-12-05ARM: implement support for read-mostly sectionsRussell King
As our SMP implementation uses MESI protocols. Grouping together data which is mostly only read together means that we avoid unnecessary cache line bouncing when this code shares a cache line with other data. In other words, cache lines associated with read-mostly data are expected to spend most of their time in shared state. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-11-19ARM: place C irq handlers in IRQ_ENTRY for ftraceRabin Vincent
When FUNCTION_GRAPH_TRACER is enabled, place do_IRQ() and friends in the IRQ_ENTRY section so that the irq-related features of the function graph tracer work. Signed-off-by: Rabin Vincent <rabin@rab.in>
2010-10-27ARM: 6465/1: Fix data abort accessing proc_info from __lookup_processor_typeTony Lindgren
Commit 5085f3ff458521045f7e43da62b8c30ea7df2e82 added better support for CONFIG_HOTPLUG_CPU by keeping proc_info around. However, depending on the Kconfig options selected, this can make the booting fail mysteriously early on. Turns out a data abort can happen in __lookup_processor in ldmia r5 {r3, r4}. When it happens the address loaded to r5 is not aligned. Fix the problem by aligning proc_info. Reported-by: Anand Gadiyar <gadiyar@ti.com> Tested-by: Anand Gadiyar <gadiyar@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-10-18Merge branch 'hotplug' into develRussell King
Conflicts: arch/arm/kernel/head-common.S
2010-10-08ARM: hotplug cpu: Keep processor information, startup code & ↵Russell King
__lookup_processor_type When hotplug CPU is enabled, we need to keep the list of supported CPUs, their setup functions, and __lookup_processor_type in place so that we can find and initialize secondary CPUs. Move these into the __CPUINIT section. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-10-08ARM: vmlinux.lds: Move unwind tables into _stext.._etextRussell King
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-10-04ARM: Allow SMP kernels to boot on UP systemsRussell King
UP systems do not implement all the instructions that SMP systems have, so in order to boot a SMP kernel on a UP system, we need to rewrite parts of the kernel. Do this using an 'alternatives' scheme, where the kernel code and data is modified prior to initialization to replace the SMP instructions, thereby rendering the problematical code ineffectual. We use the linker to generate a list of 32-bit word locations and their replacement values, and run through these replacements when we detect a UP system. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-02-15ARM: 5880/1: arm: use generic infrastructure for early paramsJeremy Kerr
The ARM setup code includes its own parser for early params, there's also one in the generic init code. This patch removes __early_init (and related code) from arch/arm/kernel/setup.c, and changes users to the generic early_init macro instead. The generic macro takes a char * argument, rather than char **, so we need to update the parser functions a little. Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-12-15ARM: use unified discard definition in linker scriptAlan Jenkins
Commit 023bf6f "linker script: unify usage of discard definition" changed the linker scripts for all architectures except for ARM. I can find no discussion about this ommision, so here are the changes for ARM. These changes are exactly parallel to the ia64 case. "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." Not boot-tested. In build testing, the modified linker script generated an identical vmlinux file. [I would like to be able to rely on this unified discard definition. I want to sort the kernel symbol tables to allow faster symbol resolution during module loading. The simplest way appears to be to generate sorted versions from vmlinux.o, link them in to vmlinux, _and discard the original unsorted tables_. This work is driven by my x86 netbook, but it is implemented at a generic level. It is possible it will benefit some ARM systems also.] Signed-off-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by-without-testing: Tejun Heo <tj@kernel.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-11-23ARM: Clean up linker script using new linker script macros.Nelson Elhage
This patch is mostly a straightforward translation. The primary side effect to the resulting vmlinux should be to increase the alignment on the initramfs to the standard PAGE_SIZE from 32 bytes. Signed-off-by: Nelson Elhage <nelhage@ksplice.com> Signed-off-by: Tim Abbott <tabbott@ksplice.com> Acked-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>