- 22 Feb, 2016 4 commits
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Kees Cook authored
With CONFIG_DEBUG_RODATA not being sensible under XIP_KERNEL, remove it from the XIP linker script. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Arnd Bergmann authored
The __start_rodata_section_aligned is only referenced by the DEBUG_RODATA code, which is only used when the MMU is enabled, but the definition fails on !MMU builds: arch/arm/kernel/vmlinux.lds:702: undefined symbol `SECTION_SHIFT' referenced in expression This hides the symbol whenever DEBUG_RODATA is disabled. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Fixes: 64ac2e74 ("ARM: 8502/1: mm: mark section-aligned portion of rodata NX") Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Arnd Bergmann authored
When CONFIG_DEBUG_ALIGN_RODATA is set, we get a link error: arch/arm/mm/built-in.o:(.data+0x4bc): undefined reference to `__start_rodata_section_aligned' However, this combination is useless, as XIP_KERNEL implies that all the RODATA is already marked readonly, so both CONFIG_DEBUG_RODATA and CONFIG_DEBUG_ALIGN_RODATA (which depends on the other) are not needed with XIP_KERNEL, and this patches enforces that using a Kconfig dependency. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Fixes: 25362dc4 ("ARM: 8501/1: mm: flip priority of CONFIG_DEBUG_RODATA") Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Jean-Philippe Brucker authored
ARMv6 CPUs do not have virtualisation extensions, but hyp-stub.S is still included into the image to keep it generic. In order to use ARMv7 instructions during HYP initialisation, add -march=armv7-a flag to hyp-stub's build. On an ARMv6 CPU, __hyp_stub_install returns as soon as it detects that the mode isn't HYP, so we will never reach those instructions. Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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- 17 Feb, 2016 1 commit
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Russell King authored
The physical-relative calculation between the XIP text and data sections introduced by the previous patch was far from obvious. Let's simplify it by turning it into a macro which takes the two (virtual) addresses. This allows us to arrange the calculation in a more obvious manner - we can make it two sub-expressions which calculate the physical address for each symbol, and then takes the difference of those physical addresses. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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- 16 Feb, 2016 6 commits
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Nicolas Pitre authored
When XIP_KERNEL is enabled, the virt to phys address translation for RAM is not the same as the virt to phys address translation for .text. The only way to know where physical RAM is located is to use PLAT_PHYS_OFFSET. The MACRO will be useful for other places where there is a similar problem. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Chris Brandt <chris.brandt@renesas.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Kevin Cernekee authored
We can still override these settings via mach/memory.h, but let's provide sensible defaults so that SPARSEMEM is available in the multiplatform kernels. Two platforms currently use SECTION_SIZE_BITS < 28, but are expected to work with 28 (albeit slightly less efficiently if not all banks are populated): - mach-rpc: uses 26 bits. Based on mach/hardware.h it looks like this platform puts RAM at 0x1000_0000 - 0x1fff_ffff, and I/O below 0x1000_0000. - mach-sa1100: uses 27 bits. mach/memory.h indicates that RAM occupies the entire range of 0xc000_0000 - 0xdfff_ffff. But Arnd says in that rpc and sa1100 will never have to use the default since they cannot be part of a multiplatform kernel, and that is unlikely to change. Several platforms need MAX_PHYSMEM_BITS >= 36 so we'll pick that as the minimum. Anything higher and we'll fail the SECTIONS_WIDTH + NODES_WIDTH + ZONES_WIDTH test in <linux/mm.h>. Some analysis from Russell King at http://lists.infradead.org/pipermail/linux-arm-kernel/2014-October/298957.html: I think this is fine in as far as it goes - this means we end up with 256 entries in the mem_section array which means it occupies one page, which I think is acceptable overhead. The other thing to be aware of here is the obvious: #if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS #error Allocator MAX_ORDER exceeds SECTION_SIZE #endif Which means that with 28 bits of section, that's a maximum allocator order of 16. We appear to allow FORCE_MAX_ZONEORDER to be set up to 64 in the case of shmobile, which doesn't seem like a sensible upper limit - and certainly isn't when sparsemem is enabled. Given this, I think that FORCE_MAX_ZONEORDER's help, and the dependencies probably could do with some improvement to make the issues more transparent. [gregory.0xf0: added notes from Arnd and Russell] Signed-off-by: Kevin Cernekee <cernekee@gmail.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Tested-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Gregory Fong <gregory.0xf0@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Kees Cook authored
Many callers either use NULL or const strings for the third argument of clk_register_clkdev. For those that do not and use a non-const string, this is a risk for format strings being accidentally processed (for example in device names). As this interface is already used as if it weren't a format string (prints nothing when NULL), and there are zero users of the format strings, remove the format string interface to make sure format strings will not leak into the clkdev. $ git grep '\bclk_register_clkdev\b' | grep % | wc -l 0 Unfortunately, all the internals expect a va_list even though they treat a NULL format string as special. To deal with this, we must pass either (..., "%s", string) or (..., NULL) so that a the va_list will be created correctly (passing the name as an argument, not as a format string). Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Masahiro Yamada authored
These two targets were introduced by commit 13d5fadf ("[ARM] Make 'i' and 'zi' targets work") to short-circuit the dependencies for 'install' and 'zinstall'. After that, commit 19514fc6 ('arm, kbuild: make "make install" not depend on vmlinux') eventually made "(z)install" equivalent to "(z)i". It is true that 'i' and 'zi' might be still useful as shorthands but the original intention had been already lost. They do not even show up in "make ARCH=arm help", so I hope this deletion does not have much impact. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Masahiro Yamada authored
"PHONY += FORCE" is already cared by scripts/Makefile.build, which this file is included from. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Jean-Philippe Brucker authored
ARMv8 introduces system registers for the Generic Interrupt Controllers CPU and virtual interfaces. When GICv3 is implemented, EL2 needs to allow the kernel to use those registers, by changing the value of ICC_HSRE. Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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- 11 Feb, 2016 12 commits
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Kees Cook authored
When rodata is large enough that it crosses a section boundary after the kernel text, mark the rest NX. This is as close to full NX of rodata as we can get without splitting page tables or doing section alignment via CONFIG_DEBUG_ALIGN_RODATA. When the config is: CONFIG_DEBUG_RODATA=y # CONFIG_DEBUG_ALIGN_RODATA is not set Before: ---[ Kernel Mapping ]--- 0x80000000-0x80100000 1M RW NX SHD 0x80100000-0x80a00000 9M ro x SHD 0x80a00000-0xa0000000 502M RW NX SHD After: ---[ Kernel Mapping ]--- 0x80000000-0x80100000 1M RW NX SHD 0x80100000-0x80700000 6M ro x SHD 0x80700000-0x80a00000 3M ro NX SHD 0x80a00000-0xa0000000 502M RW NX SHD Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Chris Brandt authored
For an XIP build, _etext does not represent the end of the binary image that needs to stay mapped into the MODULES_VADDR area. Years ago, data came before text in the memory map. However, now that the order is text/init/data, an XIP_KERNEL needs to map up to the data location in order to keep from cutting off parts of the kernel that are needed. We only map up to the beginning of data because data has already been copied, so there's no reason to keep it around anymore. A new symbol is created to make it clear what it is we are referring to. This fixes the bug where you might lose the end of your kernel area after page table setup is complete. Signed-off-by: Chris Brandt <chris.brandt@renesas.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Ard Biesheuvel authored
Commit b9b32bf7 ("ARM: use linker magic for vectors and vector stubs") updated the linker script to emit the .vectors and .stubs sections into a VMA range that is zero based and disjoint from the normal static kernel region. The reason for that was that this way, the sections can be placed exactly 4 KB apart, while the payload of the .vectors section is only 32 bytes. Since the symbols that are part of the .stubs section are emitted into the kallsyms table, they appear with zero based addresses as well, e.g., 00001004 t vector_rst 00001020 t vector_irq 000010a0 t vector_dabt 00001120 t vector_pabt 000011a0 t vector_und 00001220 t vector_addrexcptn 00001240 t vector_fiq 00001240 T vector_fiq_offset As this confuses perf when it accesses the kallsyms tables, commit 7122c3e9 ("scripts/link-vmlinux.sh: only filter kernel symbols for arm") implemented a somewhat ugly special case for ARM, where the value of CONFIG_PAGE_OFFSET is passed to scripts/kallsyms, and symbols whose addresses are below it are filtered out. Note that this special case only applies to CONFIG_XIP_KERNEL=n, not because the issue the patch addresses exists only in that case, but because finding a limit below which to apply the filtering is not entirely straightforward. Since the .vectors and .stubs sections contain position independent code that is never executed in place, we can emit it at its most likely runtime VMA (for more recent CPUs), which is 0xffff0000 for the vector table and 0xffff1000 for the stubs. Not only does this fix the perf issue with kallsyms, allowing us to drop the special case in scripts/kallsyms entirely, it also gives debuggers a more realistic view of the address space, and setting breakpoints or single stepping through code in the vector table or the stubs is more likely to work as expected on CPUs that use a high vector address. E.g., 00001240 A vector_fiq_offset ... c0c35000 T __init_begin c0c35000 T __vectors_start c0c35020 T __stubs_start c0c35020 T __vectors_end c0c352e0 T _sinittext c0c352e0 T __stubs_end ... ffff1004 t vector_rst ffff1020 t vector_irq ffff10a0 t vector_dabt ffff1120 t vector_pabt ffff11a0 t vector_und ffff1220 t vector_addrexcptn ffff1240 T vector_fiq (Note that vector_fiq_offset is now an absolute symbol, which kallsyms already ignores by default) The LMA footprint is identical with or without this change, only the VMAs are different: Before: Idx Name Size VMA LMA File off Algn ... 14 .notes 00000024 c0c34020 c0c34020 00a34020 2**2 CONTENTS, ALLOC, LOAD, READONLY, CODE 15 .vectors 00000020 00000000 c0c35000 00a40000 2**1 CONTENTS, ALLOC, LOAD, READONLY, CODE 16 .stubs 000002c0 00001000 c0c35020 00a41000 2**5 CONTENTS, ALLOC, LOAD, READONLY, CODE 17 .init.text 0006b1b8 c0c352e0 c0c352e0 00a452e0 2**5 CONTENTS, ALLOC, LOAD, READONLY, CODE ... After: Idx Name Size VMA LMA File off Algn ... 14 .notes 00000024 c0c34020 c0c34020 00a34020 2**2 CONTENTS, ALLOC, LOAD, READONLY, CODE 15 .vectors 00000020 ffff0000 c0c35000 00a40000 2**1 CONTENTS, ALLOC, LOAD, READONLY, CODE 16 .stubs 000002c0 ffff1000 c0c35020 00a41000 2**5 CONTENTS, ALLOC, LOAD, READONLY, CODE 17 .init.text 0006b1b8 c0c352e0 c0c352e0 00a452e0 2**5 CONTENTS, ALLOC, LOAD, READONLY, CODE ... Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Chris Brandt <chris.brandt@renesas.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Ard Biesheuvel authored
Commit b9b32bf7 ("ARM: use linker magic for vectors and vector stubs") introduced new global definitions of __vectors_start and __stubs_start, and changed the existing ones to have internal linkage only. However, these symbols are still visible to kallsyms, and due to the way the .vectors and .stubs sections are emitted at the base of the VMA space, these duplicate definitions have conflicting values. $ nm -n vmlinux |grep -E __vectors|__stubs 00000000 t __vectors_start 00001000 t __stubs_start c0e77000 T __vectors_start c0e77020 T __stubs_start This is completely harmless by itself, since the wrong values are local symbols that cannot be referenced by other object files directly. However, since these symbols are also listed in the kallsyms symbol table in some cases (i.e., CONFIG_KALLSYMS_ALL=y and CONFIG_XIP_KERNEL=y), having these conflicting values can be confusing. So either remove them, or make them strictly local. Acked-by: Chris Brandt <chris.brandt@renesas.com> 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>
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Chris Brandt authored
When building an XIP kernel, the linker script needs to be much different than a conventional kernel's script. Over time, it's been difficult to maintain both XIP and non-XIP layouts in one linker script. Therefore, this patch separates the two procedures into two completely different files. The new linker script is essentially a straight copy of the current script with all the non-CONFIG_XIP_KERNEL portions removed. Additionally, all CONFIG_XIP_KERNEL portions have been removed from the existing linker script...never to return again. It should be noted that this does not fix any current XIP issues, but rather is the first move in fixing them properly with subsequent patches. Signed-off-by: Chris Brandt <chris.brandt@renesas.com> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Lorenzo Pieralisi authored
ARM64 PSCI kernel interfaces that initialize idle states and implement the suspend API to enter them are generic and can be shared with the ARM architecture. To achieve that goal, this patch moves ARM64 PSCI idle management code to drivers/firmware, so that the interface to initialize and enter idle states can actually be shared by ARM and ARM64 arches back-ends. The ARM generic CPUidle implementation also requires the definition of a cpuidle_ops section entry for the kernel to initialize the CPUidle operations at boot based on the enable-method (ie ARM64 has the statically initialized cpu_ops counterparts for that purpose); therefore this patch also adds the required section entry on CONFIG_ARM for PSCI so that the kernel can initialize the PSCI CPUidle back-end when PSCI is the probed enable-method. On ARM64 this patch provides no functional change. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arch/arm64] Acked-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Jisheng Zhang <jszhang@marvell.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Jisheng Zhang <jszhang@marvell.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Lorenzo Pieralisi authored
The code enabled by the ARM_CPU_SUSPEND config option is used by kernel subsystems for purposes that go beyond system suspend so its config entry should be augmented to take more default options into account and avoid forcing its selection to prevent dependencies override. To achieve this goal, this patch reworks the ARM_CPU_SUSPEND config entry and updates its default config value (by adding the BL_SWITCHER option to it) and its dependencies (ARCH_SUSPEND_POSSIBLE), so that the symbol is still selected by default by the subsystems requiring it and at the same time enforcing the dependencies correctly. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Tomasz Figa authored
DMA allocations might be subject to certain requirements specific to the hardware using the buffers, such as availability of kernel mapping (for contents fix-ups in the driver). The only entity that knows them is the driver, so it must share this knowledge with vb2-dc. This patch extends the alloc_ctx initialization interface to let the driver specify DMA attrs, which are then stored inside the allocation context and will be used for all allocations with that context. As a side effect, all dma_*_coherent() calls are turned into dma_*_attrs() calls, because the attributes need to be carried over through all DMA operations. Signed-off-by: Tomasz Figa <tfiga@chromium.org> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Javier Martinez Canillas <javier@osg.samsung.com> Acked-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Doug Anderson authored
If we know that TLB efficiency will not be an issue when memory is accessed then it's not terribly important to allocate big chunks of memory. The whole point of allocating the big chunks was that it would make TLB usage efficient. As Marek Szyprowski indicated: Please note that mapping memory with larger pages significantly improves performance, especially when IOMMU has a little TLB cache. This can be easily observed when multimedia devices do processing of RGB data with 90/270 degree rotation Image rotation is distinctly an operation that needs to bounce around through memory, so it makes sense that TLB efficiency is important there. Video decoding, on the other hand, is a fairly sequential operation. During video decoding it's not expected that we'll be jumping all over memory. Decoding video is also pretty heavy and the TLB misses aren't a huge deal. Presumably most HW video acceleration users of dma-mapping will not care about huge pages and will set DMA_ATTR_ALLOC_SINGLE_PAGES. Allocating big chunks of memory is quite expensive, especially if we're doing it repeadly and memory is full. In one (out of tree) usage model it is common that arm_iommu_alloc_attrs() is called 16 times in a row, each one trying to allocate 4 MB of memory. This is called whenever the system encounters a new video, which could easily happen while the memory system is stressed out. In fact, on certain social media websites that auto-play video and have infinite scrolling, it's quite common to see not just one of these 16x4MB allocations but 2 or 3 right after another. Asking the system even to do a small amount of extra work to give us big chunks in this case is just not a good use of time. Allocating big chunks of memory is also expensive indirectly. Even if we ask the system not to do ANY extra work to allocate _our_ memory, we're still potentially eating up all big chunks in the system. Presumably there are other users in the system that aren't quite as flexible and that actually need these big chunks. By eating all the big chunks we're causing extra work for the rest of the system. We also may start making other memory allocations fail. While the system may be robust to such failures (as is the case with dwc2 USB trying to allocate buffers for Ethernet data and with WiFi trying to allocate buffers for WiFi data), it is yet another big performance hit. Signed-off-by: Douglas Anderson <dianders@chromium.org> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Doug Anderson authored
This patch adds the DMA_ATTR_ALLOC_SINGLE_PAGES attribute to the DMA-mapping subsystem. This attribute can be used as a hint to the DMA-mapping subsystem that it's likely not worth it to try to allocate large pages behind the scenes. Large pages are likely to make an IOMMU TLB work more efficiently but may not be worth it. See the Documentation contained in this patch for more details about this attribute and when to use it. Note that the name of the hint (DMA_ATTR_ALLOC_SINGLE_PAGES) is loosely based on the name MADV_NOHUGEPAGE. Just as there is MADV_NOHUGEPAGE vs. MADV_HUGEPAGE we could also add an "opposite" attribute to DMA_ATTR_ALLOC_SINGLE_PAGES. Without having the "opposite" attribute the lack of DMA_ATTR_ALLOC_SINGLE_PAGES means "use your best judgement about whether to use small pages or large pages". Signed-off-by: Douglas Anderson <dianders@chromium.org> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Tested-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Doug Anderson authored
The __iommu_alloc_buffer() is expected to be called to allocate pretty sizeable buffers. Upon simple tests of video I saw it trying to allocate 4,194,304 bytes. The function tries to allocate large chunks in order to optimize IOMMU TLB usage. The current function is very, very slow. One problem is the way it keeps trying and trying to allocate big chunks. Imagine a very fragmented memory that has 4M free but no contiguous pages at all. Further imagine allocating 4M (1024 pages). We'll do the following memory allocations: - For page 1: - Try to allocate order 10 (no retry) - Try to allocate order 9 (no retry) - ... - Try to allocate order 0 (with retry, but not needed) - For page 2: - Try to allocate order 9 (no retry) - Try to allocate order 8 (no retry) - ... - Try to allocate order 0 (with retry, but not needed) - ... - ... Total number of calls to alloc() calls for this case is: sum(int(math.log(i, 2)) + 1 for i in range(1, 1025)) => 9228 The above is obviously worse case, but given how slow alloc can be we really want to try to avoid even somewhat bad cases. I timed the old code with a device under memory pressure and it wasn't hard to see it take more than 120 seconds to allocate 4 megs of memory! (NOTE: testing was done on kernel 3.14, so possibly mainline would behave differently). A second problem is that allocating big chunks under memory pressure when we don't need them is just not a great idea anyway unless we really need them. We can make due pretty well with smaller chunks so it's probably wise to leave bigger chunks for other users once memory pressure is on. Let's adjust the allocation like this: 1. If a big chunk fails, stop trying to hard and bump down to lower order allocations. 2. Don't try useless orders. The whole point of big chunks is to optimize the TLB and it can really only make use of 2M, 1M, 64K and 4K sizes. We'll still tend to eat up a bunch of big chunks, but that might be the right answer for some users. A future patch could possibly add a new DMA_ATTR that would let the caller decide that TLB optimization isn't important and that we should use smaller chunks. Presumably this would be a sane strategy for some callers. Signed-off-by: Douglas Anderson <dianders@chromium.org> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Reviewed-by: Tomasz Figa <tfiga@chromium.org> Tested-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Nicolas Pitre authored
The tmp variable is used twice: first to pose as a register containing a value of zero, and then to provide a temporary register that initially is zero and get added some value. But somehow gcc decides to split those two usages in different registers. Example code: u64 div64const1000(u64 x) { u32 y = 1000; do_div(x, y); return x; } Result: div64const1000: push {r4, r5, r6, r7, lr} mov lr, #0 mov r6, r0 mov r7, r1 adr r5, .L8 ldrd r4, [r5] mov r1, lr umull r2, r3, r4, r6 cmn r2, r4 adcs r3, r3, r5 adc r2, lr, #0 umlal r3, r2, r5, r6 umlal r3, r1, r4, r7 mov r3, #0 adds r2, r1, r2 adc r3, r3, #0 umlal r2, r3, r5, r7 lsr r0, r2, #9 lsr r1, r3, #9 orr r0, r0, r3, lsl #23 pop {r4, r5, r6, r7, pc} .align 3 .L8: .word -1924145349 .word -2095944041 Full kernel build size: text data bss dec hex filename 13663814 1553940 351368 15569122 ed90e2 vmlinux Here the two instances of 'tmp' are assigned to r1 and lr. To avoid that, let's mark the first 'tmp' usage in __arch_xprod_64() with a "+r" constraint even if the register is not written to, so to create a dependency for the second usage with the effect of enforcing a single temporary register throughout. Result: div64const1000: push {r4, r5, r6, r7} movs r3, #0 adr r5, .L8 ldrd r4, [r5] umull r6, r7, r4, r0 cmn r6, r4 adcs r7, r7, r5 adc r6, r3, #0 umlal r7, r6, r5, r0 umlal r7, r3, r4, r1 mov r7, #0 adds r6, r3, r6 adc r7, r7, #0 umlal r6, r7, r5, r1 lsr r0, r6, #9 lsr r1, r7, #9 orr r0, r0, r7, lsl #23 pop {r4, r5, r6, r7} bx lr .align 3 .L8: .word -1924145349 .word -2095944041 text data bss dec hex filename 13663438 1553940 351368 15568746 ed8f6a vmlinux This time 'tmp' is assigned to r3 and used throughout. However, by being assigned to r3, that blocks usage of the r2-r3 double register slot for 64-bit values, forcing more registers to be spilled on the stack. Let's try to help it by forcing 'tmp' to the caller-saved ip register. Result: div64const1000: stmfd sp!, {r4, r5} mov ip, #0 adr r5, .L8 ldrd r4, [r5] umull r2, r3, r4, r0 cmn r2, r4 adcs r3, r3, r5 adc r2, ip, #0 umlal r3, r2, r5, r0 umlal r3, ip, r4, r1 mov r3, #0 adds r2, ip, r2 adc r3, r3, #0 umlal r2, r3, r5, r1 mov r0, r2, lsr #9 mov r1, r3, lsr #9 orr r0, r0, r3, asl #23 ldmfd sp!, {r4, r5} bx lr .align 3 .L8: .word -1924145349 .word -2095944041 text data bss dec hex filename 13662838 1553940 351368 15568146 ed8d12 vmlinux We could make the code marginally smaller yet by forcing 'tmp' to lr instead, but that would have a negative inpact on branch prediction for which "bx lr" is optimal. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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- 08 Feb, 2016 3 commits
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Kees Cook authored
The use of CONFIG_DEBUG_RODATA is generally seen as an essential part of kernel self-protection: http://www.openwall.com/lists/kernel-hardening/2015/11/30/13 Additionally, its name has grown to mean things beyond just rodata. To get ARM closer to this, we ought to rearrange the names of the configs that control how the kernel protects its memory. What was called CONFIG_ARM_KERNMEM_PERMS is realy doing the work that other architectures call CONFIG_DEBUG_RODATA. This redefines CONFIG_DEBUG_RODATA to actually do the bulk of the ROing (and NXing). In the place of the old CONFIG_DEBUG_RODATA, use CONFIG_DEBUG_ALIGN_RODATA, since that's what the option does: adds section alignment for making rodata explicitly NX, as arm does not split the page tables like arm64 does without _ALIGN_RODATA. Also adds human readable names to the sections so I could more easily debug my typos, and makes CONFIG_DEBUG_RODATA default "y" for CPU_V7. Results in /sys/kernel/debug/kernel_page_tables for each config state: # CONFIG_DEBUG_RODATA is not set # CONFIG_DEBUG_ALIGN_RODATA is not set ---[ Kernel Mapping ]--- 0x80000000-0x80900000 9M RW x SHD 0x80900000-0xa0000000 503M RW NX SHD CONFIG_DEBUG_RODATA=y CONFIG_DEBUG_ALIGN_RODATA=y ---[ Kernel Mapping ]--- 0x80000000-0x80100000 1M RW NX SHD 0x80100000-0x80700000 6M ro x SHD 0x80700000-0x80a00000 3M ro NX SHD 0x80a00000-0xa0000000 502M RW NX SHD CONFIG_DEBUG_RODATA=y # CONFIG_DEBUG_ALIGN_RODATA is not set ---[ Kernel Mapping ]--- 0x80000000-0x80100000 1M RW NX SHD 0x80100000-0x80a00000 9M ro x SHD 0x80a00000-0xa0000000 502M RW NX SHD Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Laura Abbott <labbott@fedoraproject.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
Code run via soft_restart() is run with the MMU disabled, so we need to pass the identity map physical address rather than the address obtained from virt_to_phys(). Therefore, replace virt_to_phys() with virt_to_idmap() for all callers of soft_restart(). Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
Make virt_to_idmap() return an unsigned long rather than phys_addr_t. Returning phys_addr_t here makes no sense, because the definition of virt_to_idmap() is that it shall return a physical address which maps identically with the virtual address. Since virtual addresses are limited to 32-bit, identity mapped physical addresses are as well. Almost all users already had an implicit narrowing cast to unsigned long so let's make this official and part of this interface. Tested-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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- 26 Jan, 2016 3 commits
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Andiii authored
arm: irq: l2c: do not print error in case of missing l2c from dtb In some architectures the L2 cache controller is integrated in the processor's block itself and it doesn't use any external cache controller. This means that an entry in the board's dtb related to the l2c is not necessary. Distinguish between error codes and do not print anything in case l2x0_of_init() doesn't find any L2C DTB entry and returns -ENODEV. This patch mutes the following error message: L2C: failed to init: -19 on boards like odroid-xu4, cortex A7/A15, which don't have external cache controller. Signed-off-by: Andi Shyti <andi.shyti@samsung.com> Reported-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Juri Lelli authored
Instead of looping through all cpus calling set_capacity_scale, we can initialise cpu_scale per-cpu variables to SCHED_CAPACITY_SCALE with their definition. Acked-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Juri Lelli <juri.lelli@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
Implement an ARM delay timer to be used for udelay() on orion legacy platforms. This allows us to skip the delay loop calibration at boot. It also means that udelay() will be unaffected by CPU frequency changes when cpufreq is enabled on these platforms. Tested-by: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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- 24 Jan, 2016 11 commits
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Linus Torvalds authored
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git://git.linux-mips.org/pub/scm/ralf/upstream-linusLinus Torvalds authored
Pull MIPS updates from Ralf Baechle: "This is the main pull request for MIPS for 4.5 plus some 4.4 fixes. The executive summary: - ATH79 platform improvments, use DT bindings for the ATH79 USB PHY. - Avoid useless rebuilds for zboot. - jz4780: Add NEMC, BCH and NAND device tree nodes - Initial support for the MicroChip's DT platform. As all the device drivers are missing this is still of limited use. - Some Loongson3 cleanups. - The unavoidable whitespace polishing. - Reduce clock skew when synchronizing the CPU cycle counters on CPU startup. - Add MIPS R6 fixes. - Lots of cleanups across arch/mips as fallout from KVM. - Lots of minor fixes and changes for IEEE 754-2008 support to the FPU emulator / fp-assist software. - Minor Ralink, BCM47xx and bcm963xx platform support improvments. - Support SMP on BCM63168" * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (84 commits) MIPS: zboot: Add support for serial debug using the PROM MIPS: zboot: Avoid useless rebuilds MIPS: BMIPS: Enable ARCH_WANT_OPTIONAL_GPIOLIB MIPS: bcm63xx: nvram: Remove unused bcm63xx_nvram_get_psi_size() function MIPS: bcm963xx: Update bcm_tag field image_sequence MIPS: bcm963xx: Move extended flash address to bcm_tag header file MIPS: bcm963xx: Move Broadcom BCM963xx image tag data structure MIPS: bcm63xx: nvram: Use nvram structure definition from header file MIPS: bcm963xx: Add Broadcom BCM963xx board nvram data structure MAINTAINERS: Add KVM for MIPS entry MIPS: KVM: Add missing newline to kvm_err() MIPS: Move KVM specific opcodes into asm/inst.h MIPS: KVM: Use cacheops.h definitions MIPS: Break down cacheops.h definitions MIPS: Use EXCCODE_ constants with set_except_vector() MIPS: Update trap codes MIPS: Move Cause.ExcCode trap codes to mipsregs.h MIPS: KVM: Make kvm_mips_{init,exit}() static MIPS: KVM: Refactor added offsetof()s MIPS: KVM: Convert EXPORT_SYMBOL to _GPL ...
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Linus Torvalds authored
Merge tag 'platform-drivers-x86-v4.5-2' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86 Pull x86 platform driver updates from Darren Hart: "Emergency travel prevented me from completing my final testing on this until today. Nothing here that couldn't wait until RC1 fixes, but I thought it best to get it out sooner rather than later as it does contain a build warning fix. Summary: A build warning fix, MAINTAINERS cleanup, and a new DMI quirk: ideapad-laptop: - Add Lenovo Yoga 700 to no_hw_rfkill dmi list MAINTAINERS: - Combine multiple telemetry entries intel_telemetry_debugfs: - Fix unused warnings in telemetry debugfs" * tag 'platform-drivers-x86-v4.5-2' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86: ideapad-laptop: Add Lenovo Yoga 700 to no_hw_rfkill dmi list MAINTAINERS: Combine multiple telemetry entries intel_telemetry_debugfs: Fix unused warnings in telemetry debugfs
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git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linuxLinus Torvalds authored
Pull thermal management updates from Zhang Rui: "The top merge commit was re-generated yesterday because two topic branches were dropped from this pull request in the last minute due to some unaddressed comments. All the other material has been in linux-next for quite a while. Specifics: - Enhance thermal core to handle unexpected device cooling states after fresh boot and system resume. From Zhang Rui and Chen Yu. - Several fixes and cleanups on Rockchip and RCAR thermal drivers. From Caesar Wang and Kuninori Morimoto. - Add Broxton support for Intel processor thermal reporting device driver. From Amy Wiles" * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux: thermal: trip_point_temp_store() calls thermal_zone_device_update() thermal: rcar: rcar_thermal_get_temp() return error if strange temp thermal: rcar: check irq possibility in rcar_thermal_irq_xxx() thermal: rcar: check every rcar_thermal_update_temp() return value thermal: rcar: move rcar_thermal_dt_ids to upside thermal: rockchip: Support the RK3399 SoCs in thermal driver thermal: rockchip: Support the RK3228 SoCs in thermal driver dt-bindings: rockchip-thermal: Support the RK3228/RK3399 SoCs compatible thermal: rockchip: fix a trivial typo Thermal: Enable Broxton SoC thermal reporting device thermal: constify pch_dev_ops structure Thermal: do thermal zone update after a cooling device registered Thermal: handle thermal zone device properly during system sleep Thermal: initialize thermal zone device correctly
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git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fsLinus Torvalds authored
Pull 9p updates from Eric Van Hensbergen: "Sorry for the last minute pull request, there's was a change that didn't get pulled into for-next until two weeks ago and I wanted to give it some bake time. Summary: Rework and error handling fixes, primarily in the fscatch and fd transports" * tag 'for-linus-4.5-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs: fs/9p: use fscache mutex rather than spinlock 9p: trans_fd, bail out if recv fcall if missing 9p: trans_fd, read rework to use p9_parse_header net/9p: Add device name details on error
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git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-clientLinus Torvalds authored
Pull Ceph updates from Sage Weil: "The two main changes are aio support in CephFS, and a series that fixes several issues in the authentication key timeout/renewal code. On top of that are a variety of cleanups and minor bug fixes" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: libceph: remove outdated comment libceph: kill off ceph_x_ticket_handler::validity libceph: invalidate AUTH in addition to a service ticket libceph: fix authorizer invalidation, take 2 libceph: clear messenger auth_retry flag if we fault libceph: fix ceph_msg_revoke() libceph: use list_for_each_entry_safe ceph: use i_size_{read,write} to get/set i_size ceph: re-send AIO write request when getting -EOLDSNAP error ceph: Asynchronous IO support ceph: Avoid to propagate the invalid page point ceph: fix double page_unlock() in page_mkwrite() rbd: delete an unnecessary check before rbd_dev_destroy() libceph: use list_next_entry instead of list_entry_next ceph: ceph_frag_contains_value can be boolean ceph: remove unused functions in ceph_frag.h
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git://git.samba.org/sfrench/cifs-2.6Linus Torvalds authored
Pull SMB3 fixes from Steve French: "A collection of CIFS/SMB3 fixes. It includes a couple bug fixes, a few for improved debugging of cifs.ko and some improvements to the way cifs does key generation. I do have some additional bug fixes I expect in the next week or two (to address a problem found by xfstest, and some fixes for SMB3.11 dialect, and a couple patches that just came in yesterday that I am reviewing)" * 'for-next' of git://git.samba.org/sfrench/cifs-2.6: cifs_dbg() outputs an uninitialized buffer in cifs_readdir() cifs: fix race between call_async() and reconnect() Prepare for encryption support (first part). Add decryption and encryption key generation. Thanks to Metze for helping with this. cifs: Allow using O_DIRECT with cache=loose cifs: Make echo interval tunable cifs: Check uniqueid for SMB2+ and return -ESTALE if necessary Print IP address of unresponsive server cifs: Ratelimit kernel log messages
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Josh Boyer authored
Like the Yoga 900 models the Lenovo Yoga 700 does not have a hw rfkill switch, and trying to read the hw rfkill switch through the ideapad module causes it to always reported blocking breaking wifi. This commit adds the Lenovo Yoga 700 to the no_hw_rfkill dmi list, fixing the wifi breakage. BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1295272 Tested-by: <dinyar.rabady+spam@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: Darren Hart <dvhart@linux.intel.com>
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Souvik Kumar Chakravarty authored
This patch combines all the telemetry file entries in MAINTAINERS via wildcard. Signed-off-by: Souvik Kumar Chakravarty <souvik.k.chakravarty@intel.com> Signed-off-by: Darren Hart <dvhart@linux.intel.com>
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Souvik Kumar Chakravarty authored
This patch fixes compile time warnings when CONFIG_PM_SLEEP is undefined. In this case sleep related counters are unused. Signed-off-by: Souvik Kumar Chakravarty <souvik.k.chakravarty@intel.com> Signed-off-by: Darren Hart <dvhart@linux.intel.com>
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Christoph Lameter authored
If we detect that there is nothing to do just set the flag and do not check if it was already set before. Races really do not matter. If the flag is set by any code then the shepherd will start dealing with the situation and reenable the vmstat workers when necessary again. Since commit 0eb77e98 ("vmstat: make vmstat_updater deferrable again and shut down on idle") quiet_vmstat might update cpu_stat_off and mark a particular cpu to be handled by vmstat_shepherd. This might trigger a VM_BUG_ON in vmstat_update because the work item might have been sleeping during the idle period and see the cpu_stat_off updated after the wake up. The VM_BUG_ON is therefore misleading and no more appropriate. Moreover it doesn't really suite any protection from real bugs because vmstat_shepherd will simply reschedule the vmstat_work anytime it sees a particular cpu set or vmstat_update would do the same from the worker context directly. Even when the two would race the result wouldn't be incorrect as the counters update is fully idempotent. Reported-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Christoph Lameter <cl@linux.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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