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2018-01-01errseq: Add to documentation treeMatthew Wilcox2-5/+16
- Move errseq.rst into core-api - Add errseq to the core-api index - Promote the header to a more prominent header type, otherwise we get three entries in the table of contents. - Reformat the table to look nicer and be a little more proportional in terms of horizontal width per bit (the SF bit is still disproportionately large, but there's no way to fix that). - Include errseq kernel-doc in the errseq.rst - Neaten some kernel-doc markup Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-01-01dt-bindings: at24: new optional property - wp-gpiosBartosz Golaszewski1-0/+3
AT24 EEPROMs have a write-protect pin, which - when pulled high - inhibits writes to the upper quadrant of memory (although it has been observed that on some chips it disables writing to the entire memory range). On some boards, this pin is connected to a GPIO and pulled high by default, which forces the user to manually change its state before writing. On linux this means that we either need to hog the line all the time, or set the GPIO value before writing from outside of the at24 driver. Add a new optional property to the device tree binding document, which allows to specify the GPIO line to which the write-protect pin is connected. Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Rob Herring <robh@kernel.org>
2018-01-01dt-bindings: add eeprom "no-read-rollover" propertySven Van Asbroeck1-0/+5
Adds an optional property for at24 eeproms. This parameterless property indicates that the multi-address eeprom does not automatically roll over reads to the next slave address. Signed-off-by: Sven Van Asbroeck <svendev@arcx.com> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2018-01-01dt-bindings: eeprom: rename to at24.txtWolfram Sang1-0/+0
This binding documentation is for the at24 driver, so the filename should reflect it. This avoids confusion because we also have an "eeprom" driver in Linux but it doesn't support DT even. Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2017-12-31Merge branch 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-1/+5
Pull x86 fixes from Thomas Gleixner: "A couple of fixlets for x86: - Fix the ESPFIX double fault handling for 5-level pagetables - Fix the commandline parsing for 'apic=' on 32bit systems and update documentation - Make zombie stack traces reliable - Fix kexec with stack canary - Fix the delivery mode for APICs which was missed when the x86 vector management was converted to single target delivery. Caused a regression due to the broken hardware which ignores affinity settings in lowest prio delivery mode. - Unbreak modules when AMD memory encryption is enabled - Remove an unused parameter of prepare_switch_to" * 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic: Switch all APICs to Fixed delivery mode x86/apic: Update the 'apic=' description of setting APIC driver x86/apic: Avoid wrong warning when parsing 'apic=' in X86-32 case x86-32: Fix kexec with stack canary (CONFIG_CC_STACKPROTECTOR) x86: Remove unused parameter of prepare_switch_to x86/stacktrace: Make zombie stack traces reliable x86/mm: Unbreak modules that use the DMA API x86/build: Make isoimage work on Debian x86/espfix/64: Fix espfix double-fault handling on 5-level systems
2017-12-31Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds2-2/+3
Pull scheduler fixes from Thomas Gleixner: "Three patches addressing the fallout of the CPU_ISOLATION changes especially with NO_HZ_FULL plus documentation of boot parameter dependency" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/isolation: Document boot parameters dependency on CONFIG_CPU_ISOLATION=y sched/isolation: Enable CONFIG_CPU_ISOLATION=y by default sched/isolation: Make CONFIG_NO_HZ_FULL select CONFIG_CPU_ISOLATION
2017-12-31Merge tag 'char-misc-4.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-miscLinus Torvalds1-1/+1
Pull char/misc fixes from Greg KH: "Here are six small fixes of some of the char/misc drivers that have been sent in to resolve reported issues. Nothing major, a binder use-after-free fix, some thunderbolt bugfixes, a hyper-v bugfix, and an nvmem driver fix. All of these have been in linux-next with no reported issues for a while" * tag 'char-misc-4.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: nvmem: meson-mx-efuse: fix reading from an offset other than 0 binder: fix proc->files use-after-free vmbus: unregister device_obj->channels_kset thunderbolt: Mask ring interrupt properly when polling starts MAINTAINERS: Add thunderbolt.rst to the Thunderbolt driver entry thunderbolt: Make pathname to force_power shorter
2017-12-31ARM: at91: Document new TCB bindingsAlexandre Belloni2-32/+56
The current binding for the TCB is not flexible enough for some use cases and prevents proper utilization of all the channels. Acked-by: Rob Herring <robh@kernel.org> Cc: devicetree@vger.kernel.org Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-12-31Merge branch 'i2c-mux/for-next' of https://github.com/peda-r/i2c-mux into i2c/for-4.16Wolfram Sang4-12/+43
"A couple of patches this time. Just some more compatibles for the pca954x driver and an error handling tweak for the reg driver."
2017-12-30i2c: mux: pca954x: add support for NXP PCA984x familyAdrian Fiergolski1-2/+11
This patch extends the current i2c-mux-pca954x driver and adds support for a newer PCA984x family of the I2C switches and multiplexers from NXP. Signed-off-by: Adrian Fiergolski <adrian.fiergolski@cern.ch> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Peter Rosin <peda@axentia.se>
2017-12-29Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds2-2/+11
Pull x86 page table isolation updates from Thomas Gleixner: "This is the final set of enabling page table isolation on x86: - Infrastructure patches for handling the extra page tables. - Patches which map the various bits and pieces which are required to get in and out of user space into the user space visible page tables. - The required changes to have CR3 switching in the entry/exit code. - Optimizations for the CR3 switching along with documentation how the ASID/PCID mechanism works. - Updates to dump pagetables to cover the user space page tables for W+X scans and extra debugfs files to analyze both the kernel and the user space visible page tables The whole functionality is compile time controlled via a config switch and can be turned on/off on the command line as well" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits) x86/ldt: Make the LDT mapping RO x86/mm/dump_pagetables: Allow dumping current pagetables x86/mm/dump_pagetables: Check user space page table for WX pages x86/mm/dump_pagetables: Add page table directory to the debugfs VFS hierarchy x86/mm/pti: Add Kconfig x86/dumpstack: Indicate in Oops whether PTI is configured and enabled x86/mm: Clarify the whole ASID/kernel PCID/user PCID naming x86/mm: Use INVPCID for __native_flush_tlb_single() x86/mm: Optimize RESTORE_CR3 x86/mm: Use/Fix PCID to optimize user/kernel switches x86/mm: Abstract switching CR3 x86/mm: Allow flushing for future ASID switches x86/pti: Map the vsyscall page if needed x86/pti: Put the LDT in its own PGD if PTI is on x86/mm/64: Make a full PGD-entry size hole in the memory map x86/events/intel/ds: Map debug buffers in cpu_entry_area x86/cpu_entry_area: Add debugstore entries to cpu_entry_area x86/mm/pti: Map ESPFIX into user space x86/mm/pti: Share entry text PMD x86/entry: Align entry text section to PMD boundary ...
2017-12-29Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller3-15/+13
net/ipv6/ip6_gre.c is a case of parallel adds. include/trace/events/tcp.h is a little bit more tricky. The removal of in-trace-macro ifdefs in 'net' paralleled with moving show_tcp_state_name and friends over to include/trace/events/sock.h in 'net-next'. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-29media: v4l: Fix references in Intel IPU3 Bayer documentationSakari Ailus1-4/+4
The references in Intel IPU3 Bayer format documentation were wrong. Fix them. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-12-29media: dmx.h documentation: fix a warningMauro Carvalho Chehab1-0/+2
/devel/v4l/patchwork/Documentation/output/dmx.h.rst:6: WARNING: undefined label: dmx_dqbuf (if the link has no caption the label must precede a section header) This is defined together with DMX_QBUF. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-12-29media: dvb kAPI docs: document dvb_vb2.hMauro Carvalho Chehab1-0/+5
Document the data structures and functions inside this kAPI header. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-12-29media: doc-rst: add IPU3 raw10 bayer pixel format definitionsYong Zhi2-0/+336
The formats added by this patch are: V4L2_PIX_FMT_IPU3_SBGGR10 V4L2_PIX_FMT_IPU3_SGBRG10 V4L2_PIX_FMT_IPU3_SGRBG10 V4L2_PIX_FMT_IPU3_SRGGB10 Signed-off-by: Hyungwoo Yang <hyungwoo.yang@intel.com> Signed-off-by: Yong Zhi <yong.zhi@intel.com> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-12-29dt-bindings: simplefb-sunxi: add pipelines for DE2Icenowy Zheng1-0/+4
As we're going to add simplefb support for Allwinner SoCs with DE2, add suitable pipeline strings in the device tree binding. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Icenowy Zheng <icenowy@aosc.io> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
2017-12-29dt-bindings: fix the binding of Allwinner DE2 CCU of A83T and H3Icenowy Zheng1-2/+3
The DE2 CCU is different on A83T and H3 -- the parent of the clocks on A83T is PLL_DE but on H3 it's the DE module clock. This is not noticed when I develop the DE2 CCU driver. Fix the binding by using different compatibles for A83T and H3, adding notes for the PLL_DE usage on A83T, and change the binding example's compatible from A83T to H3 (as it specifies the DE module clock). Fixes: ed74f8a8a679 ("dt-bindings: add binding for the Allwinner DE2 CCU") Signed-off-by: Icenowy Zheng <icenowy@aosc.io> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
2017-12-28dt-bindings: watchdog: Add Spreadtrum watchdog documentationEric Long1-0/+19
This patch adds the documentation for Spreadtrum watchdog driver. Signed-off-by: Eric Long <eric.long@spreadtrum.com> Acked-by: Rob Herring <robh@kernel.org> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2017-12-28dt-bindings: watchdog: renesas-wdt: Add support for the r8a77970 wdtGeert Uytterhoeven1-1/+2
Document support for the Watchdog Timer (WDT) Controller in the Renesas R-Car V3M (r8a77970) SoC. Restore sort order while at it. No driver update is needed. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Rob Herring <robh@kernel.org> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2017-12-28watchdog: gemini/ftwdt010: rename DT bindingsLinus Walleij2-20/+8
The device tree bindings are in two copies and also should be consolidated into a single Faraday Technology FTWDT010 binding since we uncovered that this IP part is a standard IP from Faraday. Cc: devicetree@vger.kernel.org Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2017-12-28dt: watchdog: Document compatibility with JZ4780Mathieu Malaterre1-2/+2
Suggested-by: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com> Signed-off-by: Mathieu Malaterre <malat@debian.org> Acked-by: Rob Herring <robh@kernel.org> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2017-12-28dt-bindings: watchdog: Add Realtek RTD1295Andreas Färber1-0/+17
Add a binding for the Realtek RTD1295 watchdog. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Andreas Färber <afaerber@suse.de> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2017-12-28media: move dvb kAPI headers to include/mediaMauro Carvalho Chehab5-13/+13
Except for DVB, all media kAPI headers are at include/media. Move the headers to it. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-12-28dt-bindings: net: add DT bindings for Socionext UniPhier AVEKunihiko Hayashi1-0/+48
DT bindings for the AVE ethernet controller found on Socionext's UniPhier platforms. Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com> Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org> Acked-by: Rob Herring <robh@kernel.org> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-28media: dvb-core: get rid of mmap reserved fieldMauro Carvalho Chehab4-8/+0
The "reserved" field was a way, used at V4L2 API, to add new data to existing structs without breaking userspace. However, there are now clever ways of doing that, without needing to add an uneeded overhead. So, get rid of them. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-12-28media: dvb uAPI docs: document mmap-related ioctlsMauro Carvalho Chehab5-0/+320
5 new ioctls were added to the DVB demux API, in order to handle memory maped I/O. Add documentation for them. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-12-28media: dvb uAPI docs: document demux mmap/munmap syscallsMauro Carvalho Chehab3-0/+172
With the new dmx mmap interface, those two syscalls are now handled by the subsystem. Document them. This patch is based on the V4L2 text for those ioctls. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-12-28x86/apic: Update the 'apic=' description of setting APIC driverDou Liyang1-1/+5
There are two consumers of apic=: the APIC debug level and the low level generic architecture code, but Linux just documented the first one. Append the second description. Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: peterz@infradead.org Cc: rdunlap@infradead.org Cc: corbet@lwn.net Link: https://lkml.kernel.org/r/20171204040313.24824-2-douly.fnst@cn.fujitsu.com
2017-12-27Merge tag 'sound-4.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/soundLinus Torvalds2-2/+2
Pull sound fixes from Takashi Iwai: "It seems that Santa overslept with a bunch of gifts; the majority of changes here are various device-specific ASoC fixes, most notably the revert of rcar IOMMU support and fsl_ssi AC97 fixes, but also lots of small fixes for codecs. Besides that, the usual HD-audio quirks and fixes are included, too" * tag 'sound-4.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (31 commits) ALSA: hda - Fix missing COEF init for ALC225/295/299 ALSA: hda: Drop useless WARN_ON() ALSA: hda - change the location for one mic on a Lenovo machine ALSA: hda - fix headset mic detection issue on a Dell machine ALSA: hda - Add MIC_NO_PRESENCE fixup for 2 HP machines ASoC: rsnd: fixup ADG register mask ASoC: rt5514-spi: only enable wakeup when fully initialized ASoC: nau8825: fix issue that pop noise when start capture ASoC: rt5663: Fix the wrong result of the first jack detection ASoC: rsnd: ssi: fix race condition in rsnd_ssi_pointer_update ASoC: Intel: Change kern log level to avoid unwanted messages ASoC: atmel-classd: select correct Kconfig symbol ASoC: wm_adsp: Fix validation of firmware and coeff lengths ASoC: Intel: Skylake: Do not check dev_type for dmic link type ASoC: rockchip: disable clock on error ASoC: tlv320aic31xx: Fix GPIO1 register definition ASoC: codecs: msm8916-wcd: Fix supported formats ASoC: fsl_asrc: Fix typo in a field define ASoC: rsnd: ssiu: clear SSI_MODE for non TDM Extended modes ASoC: da7218: Correct IRQ level in DT binding example ...
2017-12-27Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-nextDavid S. Miller1-6/+14
Steffen Klassert says: ==================== pull request (net-next): ipsec-next 2017-12-22 1) Separate ESP handling from segmentation for GRO packets. This unifies the IPsec GSO and non GSO codepath. 2) Add asynchronous callbacks for xfrm on layer 2. This adds the necessary infrastructure to core networking. 3) Allow to use the layer2 IPsec GSO codepath for software crypto, all infrastructure is there now. 4) Also allow IPsec GSO with software crypto for local sockets. 5) Don't require synchronous crypto fallback on IPsec offloading, it is not needed anymore. 6) Check for xdo_dev_state_free and only call it if implemented. From Shannon Nelson. 7) Check for the required add and delete functions when a driver registers xdo_dev_ops. From Shannon Nelson. 8) Define xfrmdev_ops only with offload config. From Shannon Nelson. 9) Update the xfrm stats documentation. From Shannon Nelson. Please pull or let me know if there are problems. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-27phylib: rename reset-(post-)delay-us to reset-(de)assert-usRichard Leitner1-4/+4
As suggested by Rob Herring [1] rename the previously introduced reset-{,post-}delay-us bindings to the clearer reset-{,de}assert-us [1] https://patchwork.kernel.org/patch/10104905/ Signed-off-by: Richard Leitner <richard.leitner@skidata.com> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-26dt-bindings: imx6q-pcie: Add required property for i.MX6SXFabio Estevam1-0/+1
i.MX6SX needs a PCI 'power-domains' entry, so add it to its required properties section. Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-12-26mmc: Don't reference Linux-specific OF_GPIO_ACTIVE_LOW flag in DT bindingTuomas Tynkkynen1-2/+2
OF_GPIO_ACTIVE_LOW is a Linux implementation detail. The binding document should be referring to GPIO_ACTIVE_LOW found in include/dt-bindings/gpio/gpio.h. Signed-off-by: Tuomas Tynkkynen <tuomas@tuxera.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-12-26dt-bindings: net: mediatek: add condition to property mediatek, pctlSean Wang1-1/+1
The property "mediatek,pctl" is only required for SoCs such as MT2701 and MT7623, so adding a few words for stating the condition. Signed-off-by: Sean Wang <sean.wang@mediatek.com> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-26dt-bindings: Use lower case hex in unit-addressesRob Herring48-64/+64
DT unit addresses should be lower case hex. Fix all the binding examples. Converted with the following command from Krzysztof Kozlowski: sed -e 's/@\([a-fA-F0-9_-]*\) {/@\L\1 {/' -i $(find Documentation/devicetree/bindings -name '*.txt') Signed-off-by: Rob Herring <robh@kernel.org>
2017-12-26soc: imx: gpc: Add i.MX6SX PCI power domainFabio Estevam1-0/+3
i.MX6SX has a PCI power domain in PGC. Add support for it. Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com> Acked-by: Lucas Stach <l.stach@pengutronix.de> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2017-12-26dt-bindings: imx-gpcv2: Fix the unit addressFabio Estevam1-2/+2
In the provided example the unit address does not match the 'reg' value, as IMX7_POWER_DOMAIN_PCIE_PHY is defined as 1. Fix the unit address and avoid using defines in reg as per Rob Herring's recommendation. Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2017-12-26of: documentation: add bindings documentation for TS-4600Sebastien Bourdelin1-0/+5
This adds the documentation for the TS-4600 by Technologic Systems. Signed-off-by: Sebastien Bourdelin <sebastien.bourdelin@savoirfairelinux.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2017-12-26of: documentation: add bindings documentation for TS-7970Sebastien Bourdelin1-0/+6
This adds the documentation for the TS-7970 by Technologic Systems. Signed-off-by: Sebastien Bourdelin <sebastien.bourdelin@savoirfairelinux.com> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2017-12-26dt-bindings: display: Add bindings for SGD GKTW70SDAE4SE PanelNeil Armstrong1-0/+41
The GKTW70SDAE4SE is an LVDS display panel. Their bindings are modelled on the the LVDS panel bindings. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2017-12-26dt-bindings: Add vendor prefix for Solomon Goldentek Display CorporationNeil Armstrong1-0/+1
Solomon Goldentek Display Corporation is a Taiwanese LCD/LCM manufacturer. Company Site: http://www.goldentek.com.tw Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2017-12-25VFS: don't keep disconnected dentries on d_anonNeilBrown1-7/+18
The original purpose of the per-superblock d_anon list was to keep disconnected dentries in the cache between consecutive requests to the NFS server. Dentries can be disconnected if a client holds a file open and repeatedly performs IO on it, and if the server drops the dentry, whether due to memory pressure, server restart, or "echo 3 > /proc/sys/vm/drop_caches". This purpose was thwarted by commit 75a6f82a0d10 ("freeing unlinked file indefinitely delayed") which caused disconnected dentries to be freed as soon as their refcount reached zero. This means that, when a dentry being used by nfsd gets disconnected, a new one needs to be allocated for every request (unless requests overlap). As the dentry has no name, no parent, and no children, there is little of value to cache. As small memory allocations are typically fast (from per-cpu free lists) this likely has little cost. This means that the original purpose of s_anon is no longer relevant: there is no longer any need to keep disconnected dentries on a list so they appear to be hashed. However, s_anon now has a new use. When you mount an NFS filesystem, the dentry stored in s_root is just a placebo. The "real" root dentry is allocated using d_obtain_root() and so it kept on the s_anon list. I don't know the reason for this, but suspect it related to NFSv4 where a mount of "server:/some/path" require NFS to look up the root filehandle on the server, then walk down "/some" and "/path" to get the filehandle to mount. Whatever the reason, NFS depends on the s_anon list and on shrink_dcache_for_umount() pruning all dentries on this list. So we cannot simply remove s_anon. We could just leave the code unchanged, but apart from that being potentially confusing, the (unfair) bit-spin-lock which protects s_anon can become a bottle neck when lots of disconnected dentries are being created. So this patch renames s_anon to s_roots, and stops storing disconnected dentries on the list. Only dentries obtained with d_obtain_root() are now stored on this list. There are many fewer of these (only NFS and NILFS2 use the call, and only during filesystem mount) so contention on the bit-lock will not be a problem. Possibly an alternate solution should be found for NFS and NILFS2, but that would require understanding their needs first. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-12-23x86/pti: Put the LDT in its own PGD if PTI is onAndy Lutomirski1-1/+2
With PTI enabled, the LDT must be mapped in the usermode tables somewhere. The LDT is per process, i.e. per mm. An earlier approach mapped the LDT on context switch into a fixmap area, but that's a big overhead and exhausted the fixmap space when NR_CPUS got big. Take advantage of the fact that there is an address space hole which provides a completely unused pgd. Use this pgd to manage per-mm LDT mappings. This has a down side: the LDT isn't (currently) randomized, and an attack that can write the LDT is instant root due to call gates (thanks, AMD, for leaving call gates in AMD64 but designing them wrong so they're only useful for exploits). This can be mitigated by making the LDT read-only or randomizing the mapping, either of which is strightforward on top of this patch. This will significantly slow down LDT users, but that shouldn't matter for important workloads -- the LDT is only used by DOSEMU(2), Wine, and very old libc implementations. [ tglx: Cleaned it up. ] Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Laight <David.Laight@aculab.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kees Cook <keescook@chromium.org> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-23x86/mm/64: Make a full PGD-entry size hole in the memory mapAndy Lutomirski1-2/+2
Shrink vmalloc space from 16384TiB to 12800TiB to enlarge the hole starting at 0xff90000000000000 to be a full PGD entry. A subsequent patch will use this hole for the pagetable isolation LDT alias. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Laight <David.Laight@aculab.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kees Cook <keescook@chromium.org> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-23x86/pti: Add the pti= cmdline option and documentationBorislav Petkov1-0/+6
Keep the "nopti" optional for traditional reasons. [ tglx: Don't allow force on when running on XEN PV and made 'on' printout conditional ] Requested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirsky <luto@kernel.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Laight <David.Laight@aculab.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Eduardo Valentin <eduval@amazon.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will.deacon@arm.com> Cc: aliguori@amazon.com Cc: daniel.gruss@iaik.tugraz.at Cc: hughd@google.com Cc: keescook@google.com Link: https://lkml.kernel.org/r/20171212133952.10177-1-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-23x86/mm/pti: Add infrastructure for page table isolationThomas Gleixner1-0/+2
Add the initial files for kernel page table isolation, with a minimal init function and the boot time detection for this misfeature. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Laight <David.Laight@aculab.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Eduardo Valentin <eduval@amazon.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will.deacon@arm.com> Cc: aliguori@amazon.com Cc: daniel.gruss@iaik.tugraz.at Cc: hughd@google.com Cc: keescook@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-23Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-13/+11
Pull x86 PTI preparatory patches from Thomas Gleixner: "Todays Advent calendar window contains twentyfour easy to digest patches. The original plan was to have twenty three matching the date, but a late fixup made that moot. - Move the cpu_entry_area mapping out of the fixmap into a separate address space. That's necessary because the fixmap becomes too big with NRCPUS=8192 and this caused already subtle and hard to diagnose failures. The top most patch is fresh from today and cures a brain slip of that tall grumpy german greybeard, who ignored the intricacies of 32bit wraparounds. - Limit the number of CPUs on 32bit to 64. That's insane big already, but at least it's small enough to prevent address space issues with the cpu_entry_area map, which have been observed and debugged with the fixmap code - A few TLB flush fixes in various places plus documentation which of the TLB functions should be used for what. - Rename the SYSENTER stack to CPU_ENTRY_AREA stack as it is used for more than sysenter now and keeping the name makes backtraces confusing. - Prevent LDT inheritance on exec() by moving it to arch_dup_mmap(), which is only invoked on fork(). - Make vysycall more robust. - A few fixes and cleanups of the debug_pagetables code. Check PAGE_PRESENT instead of checking the PTE for 0 and a cleanup of the C89 initialization of the address hint array which already was out of sync with the index enums. - Move the ESPFIX init to a different place to prepare for PTI. - Several code moves with no functional change to make PTI integration simpler and header files less convoluted. - Documentation fixes and clarifications" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) x86/cpu_entry_area: Prevent wraparound in setup_cpu_entry_area_ptes() on 32bit init: Invoke init_espfix_bsp() from mm_init() x86/cpu_entry_area: Move it out of the fixmap x86/cpu_entry_area: Move it to a separate unit x86/mm: Create asm/invpcid.h x86/mm: Put MMU to hardware ASID translation in one place x86/mm: Remove hard-coded ASID limit checks x86/mm: Move the CR3 construction functions to tlbflush.h x86/mm: Add comments to clarify which TLB-flush functions are supposed to flush what x86/mm: Remove superfluous barriers x86/mm: Use __flush_tlb_one() for kernel memory x86/microcode: Dont abuse the TLB-flush interface x86/uv: Use the right TLB-flush API x86/entry: Rename SYSENTER_stack to CPU_ENTRY_AREA_entry_stack x86/doc: Remove obvious weirdnesses from the x86 MM layout documentation x86/mm/64: Improve the memory map documentation x86/ldt: Prevent LDT inheritance on exec x86/ldt: Rework locking arch, mm: Allow arch_dup_mmap() to fail x86/vsyscall/64: Warn and fail vsyscall emulation in NATIVE mode ...
2017-12-22Merge branch 'docs-next' of git://git.lwn.net/linux into patchworkMauro Carvalho Chehab112-714/+1114
* 'docs-next' of git://git.lwn.net/linux: (888 commits) w1_netlink.h: add support for nested structs scripts: kernel-doc: apply filtering rules to warnings scripts: kernel-doc: improve nested logic to handle multiple identifiers scripts: kernel-doc: handle nested struct function arguments scripts: kernel-doc: print the declaration name on warnings scripts: kernel-doc: get rid of $nested parameter scripts: kernel-doc: parse next structs/unions scripts: kernel-doc: replace tabs by spaces scripts: kernel-doc: change default to ReST format scripts: kernel-doc: improve argument handling scripts: kernel-doc: get rid of unused output formats docs: get rid of kernel-doc-nano-HOWTO.txt docs: kernel-doc.rst: add documentation about man pages docs: kernel-doc.rst: improve typedef documentation docs: kernel-doc.rst: improve structs chapter docs: kernel-doc.rst: improve function documentation section docs: kernel-doc.rst: improve private members description docs: kernel-doc.rst: better describe kernel-doc arguments docs: fix process/submit-checklist.rst Sphinx warning docs: ftrace-uses.rst fix varios code-block directives ...
2017-12-22x86/cpu_entry_area: Move it out of the fixmapThomas Gleixner1-0/+2
Put the cpu_entry_area into a separate P4D entry. The fixmap gets too big and 0-day already hit a case where the fixmap PTEs were cleared by cleanup_highmap(). Aside of that the fixmap API is a pain as it's all backwards. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>