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Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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Pull perf updates and fixes from Ingo Molnar:
"These are almost all tooling updates: 'perf top', 'perf trace' and
'perf script' fixes and updates, an UAPI header sync with the merge
window versions, license marker updates, much improved Sparc support
from David Miller, and a number of fixes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (66 commits)
perf intel-pt/bts: Calculate cpumode for synthesized samples
perf intel-pt: Insert callchain context into synthesized callchains
perf tools: Don't clone maps from parent when synthesizing forks
perf top: Start display thread earlier
tools headers uapi: Update linux/if_link.h header copy
tools headers uapi: Update linux/netlink.h header copy
tools headers: Sync the various kvm.h header copies
tools include uapi: Update linux/mmap.h copy
perf trace beauty: Use the mmap flags table generated from headers
perf beauty: Wire up the mmap flags table generator to the Makefile
perf beauty: Add a generator for MAP_ mmap's flag constants
tools include uapi: Update asound.h copy
tools arch uapi: Update asm-generic/unistd.h and arm64 unistd.h copies
tools include uapi: Update linux/fs.h copy
perf callchain: Honour the ordering of PERF_CONTEXT_{USER,KERNEL,etc}
perf cs-etm: Correct CPU mode for samples
perf unwind: Take pgoff into account when reporting elf to libdwfl
perf top: Do not use overwrite mode by default
perf top: Allow disabling the overwrite mode
perf trace: Beautify mount's first pathname arg
...
Pull irq fixes from Ingo Molnar:
"An irqchip driver fix and a memory (over-)allocation fix"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/irq-mvebu-sei: Fix a NULL vs IS_ERR() bug in probe function
irq/matrix: Fix memory overallocation
Pull perf/urgent improvements and fixes from Arnaldo Carvalho de Melo:
- Fixes dealing with the removal of the fallback to looking up samples
marked as userspace in the kernel maps, done recently:
- For intel-pt, that was setting the synthesized header misc field
as PERF_RECORD_MISC_USER, depending thus on the fallback to take
place, now it sets as USER or KERNEL according to x86 specific
knowledge. Also now it inserts the PERF_CONTEXT_{USER,KERNEL} into
the PERF_SAMPLE_CALLCHAINs it synthesizes from hw traces (Adrian Hunter)
- Similar fixes for the cs-etm ARM HW trace code, that used the Intel PT
model as a starting point (Leo Yan)
- For the "caller" callchain order, where the callchain returned by the
kernel was simply reversed without taking into account the
PERF_CONTEXT_{USER,KERNEL,etc} markers from where to define if an entry
was for kernel or userspace, working just because the map lookup fallback
was in place (David S. Miller)
- Allow for selecting if 'overwrite' mode should be used in 'perf top' and
make the default for it not to be used. This is due to problems with the
current implementation where the pausing used ends up making 'perf top'
miss PERF_RECORD_{MMAP,FORK,EXEC,etc} events, which with short lifetime
threads workloads leads quickly to many "unknown" maps (and thus symbols)
to appear in the UI. Workloads with long thread lifetimes and with few
metadata events can still use --overwrite to take advantage of the
overwrite mode (Arnaldo Carvalho de Melo)
- Start 'perf top''s display thread earlier, so that the screen doesn't
remain blank for too long at tool start (David S. Miller)
- Don't clone maps from parent when synthesizing forks, to avoid the inevitable
flurry of overlapping maps as we process the synthesized MMAP2 events that get
delivered shortly thereafter. (David S. Miller)
- Take pgoff into account when reporting elf to libdwfl, now the unwinding
results are the same with elfutils's libdwfl and libunwind (Milian Wolff)
- Update lotsa kernel ABI headers (Arnaldo Carvalho de Melo)
- 'perf trace' syscall arg beautification improvements to allow for
handling args such as mount's 'flags', where maks have to be ignored
before considering what is left, that, if only zeroes, is suppressed
like other args without such masks (Arnaldo Carvalho de Melo)
- Beautify mount's 'source' and 'flags' args (Arnaldo Carvalho de Melo)
- Generate mmap's flags bit constants from linux/mman.h and all the
arch specific mman.h files, so that no changes in the main 'perf trace'
source files is required when new flags get added (Arnaldo Carvalho de Melo)
- Consider syscall aliases, so that 'perf trace -e umount' works and we don't
have to use 'umount2' (that works as well, just not required) (Arnaldo Carvalho de Melo)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull ARM SoC fixes from Olof Johansson:
"A few fixes who have come in near or during the merge window:
- Removal of a VLA usage in Marvell mpp platform code
- Enable some IPMI options for ARM64 servers by default, helps
testing
- Enable PREEMPT on 32-bit ARMv7 defconfig
- Minor fix for stm32 DT (removal of an unused DMA property)
- Bugfix for TI OMAP1-based ams-delta (-EINVAL -> IRQ_NOTCONNECTED)"
* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
ARM: dts: stm32: update HASH1 dmas property on stm32mp157c
ARM: orion: avoid VLA in orion_mpp_conf
ARM: defconfig: Update multi_v7 to use PREEMPT
arm64: defconfig: Enable some IPMI configs
soc: ti: QMSS: Fix usage of irq_set_affinity_hint
ARM: OMAP1: ams-delta: Fix impossible .irq < 0
The devm_ioremap_resource() function never returns NULL, it returns
error pointers.
Fixes: 61ce8d8d8a81 ("irqchip/irq-mvebu-sei: Add new driver for Marvell SEI")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Gregory Clement <gregory.clement@bootlin.com>
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: kernel-janitors@vger.kernel.org
Link: https://lkml.kernel.org/r/20181013102246.GD16086@mwanda
Replace a bunch of spaces with tab, cleans up indentation
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-janitors@vger.kernel.org
Link: http://lkml.kernel.org/r/20181029233211.21475-1-colin.king@canonical.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In the absence of a fallback, samples must provide a correct cpumode for
the 'ip'. Do that now there is no fallback.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: stable@vger.kernel.org # 4.19
Link: http://lkml.kernel.org/r/20181031091043.23465-6-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull more arm64 updates from Catalin Marinas:
- fix W+X page (mark RO) allocated by the arm64 kprobes code
- Makefile fix for .i files in out of tree modules
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: kprobe: make page to RO mode when allocate it
arm64: kdump: fix small typo
arm64: makefile fix build of .i file in external module case
Fix for omap1 ams-delta irq
We need to use IRQ_NOTCONNECTED instead of -EINVAL for
ams_delta_modem_ports irq.
* tag 'omap-for-v4.20/omap1-fix-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
ARM: OMAP1: ams-delta: Fix impossible .irq < 0
Signed-off-by: Olof Johansson <olof@lixom.net>
IRQ_MATRIX_SIZE is the number of longs needed for a bitmap, multiplied by
the size of a long, yielding a byte count. But it is used to size an array
of longs, which is way more memory than is needed.
Change IRQ_MATRIX_SIZE so it is just the number of longs needed and the
arrays come out the correct size.
Fixes: 2f75d9e1c905 ("genirq: Implement bitmap matrix allocator")
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: KY Srinivasan <kys@microsoft.com>
Link: https://lkml.kernel.org/r/1541032428-10392-1-git-send-email-mikelley@microsoft.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In the absence of a fallback, callchains must encode also the callchain
context. Do that now there is no fallback.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: stable@vger.kernel.org # 4.19
Link: http://lkml.kernel.org/r/100ea2ec-ed14-b56d-d810-e0a6d2f4b069@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull dma-mapping fix from Christoph Hellwig:
"Avoid compile warnings on non-default arm64 configs"
* tag 'dma-mapping-4.20-2' of git://git.infradead.org/users/hch/dma-mapping:
arm64: fix warnings without CONFIG_IOMMU_DMA
Commit 1404d6f13e47 ("arm64: dump: Add checking for writable and exectuable pages")
has successfully identified code that leaves a page with W+X
permissions.
[ 3.245140] arm64/mm: Found insecure W+X mapping at address (____ptrval____)/0xffff000000d90000
[ 3.245771] WARNING: CPU: 0 PID: 1 at ../arch/arm64/mm/dump.c:232 note_page+0x410/0x420
[ 3.246141] Modules linked in:
[ 3.246653] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc5-next-20180928-00001-ge70ae259b853-dirty #62
[ 3.247008] Hardware name: linux,dummy-virt (DT)
[ 3.247347] pstate: 80000005 (Nzcv daif -PAN -UAO)
[ 3.247623] pc : note_page+0x410/0x420
[ 3.247898] lr : note_page+0x410/0x420
[ 3.248071] sp : ffff00000804bcd0
[ 3.248254] x29: ffff00000804bcd0 x28: ffff000009274000
[ 3.248578] x27: ffff00000921a000 x26: ffff80007dfff000
[ 3.248845] x25: ffff0000093f5000 x24: ffff000009526f6a
[ 3.249109] x23: 0000000000000004 x22: ffff000000d91000
[ 3.249396] x21: ffff000000d90000 x20: 0000000000000000
[ 3.249661] x19: ffff00000804bde8 x18: 0000000000000400
[ 3.249924] x17: 0000000000000000 x16: 0000000000000000
[ 3.250271] x15: ffffffffffffffff x14: 295f5f5f5f6c6176
[ 3.250594] x13: 7274705f5f5f5f28 x12: 2073736572646461
[ 3.250941] x11: 20746120676e6970 x10: 70616d20582b5720
[ 3.251252] x9 : 6572756365736e69 x8 : 3039643030303030
[ 3.251519] x7 : 306666666678302f x6 : ffff0000095467b2
[ 3.251802] x5 : 0000000000000000 x4 : 0000000000000000
[ 3.252060] x3 : 0000000000000000 x2 : ffffffffffffffff
[ 3.252323] x1 : 4d151327adc50b00 x0 : 0000000000000000
[ 3.252664] Call trace:
[ 3.252953] note_page+0x410/0x420
[ 3.253186] walk_pgd+0x12c/0x238
[ 3.253417] ptdump_check_wx+0x68/0xf8
[ 3.253637] mark_rodata_ro+0x68/0x98
[ 3.253847] kernel_init+0x38/0x160
[ 3.254103] ret_from_fork+0x10/0x18
kprobes allocates a writable executable page with module_alloc() in
order to store executable code.
Reworked to that when allocate a page it sets mode RO. Inspired by
commit 63fef14fc98a ("kprobes/x86: Make insn buffer always ROX and use text_poke()").
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
[catalin.marinas@arm.com: removed unnecessary casts]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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