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2017-08-20genirq/ipi: Fixup checks against nr_cpu_idsAlexey Dobriyan1-2/+2
Valid CPU ids are [0, nr_cpu_ids-1] inclusive. Fixes: 3b8e29a82dd1 ("genirq: Implement ipi_send_mask/single()") Fixes: f9bce791ae2a ("genirq: Add a new function to get IPI reverse mapping") Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20170819095751.GB27864@avx2
2017-08-18genirq: Restore trigger settings in irq_modify_status()Marc Zyngier1-2/+8
irq_modify_status starts by clearing the trigger settings from irq_data before applying the new settings, but doesn't restore them, leaving them to IRQ_TYPE_NONE. That's pretty confusing to the potential request_irq() that could follow. Instead, snapshot the settings before clearing them, and restore them if the irq_modify_status() invocation was not changing the trigger. Fixes: 1e2a7d78499e ("irqdomain: Don't set type when mapping an IRQ") Reported-and-tested-by: jeffy <jeffy.chen@rock-chips.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jon Hunter <jonathanh@nvidia.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20170818095345.12378-1-marc.zyngier@arm.com
2017-07-27genirq/cpuhotplug: Revert "Set force affinity flag on hotplug migration"Thomas Gleixner1-2/+7
That commit was part of the changes moving x86 to the generic CPU hotplug interrupt migration code. The force flag was required on x86 before the hierarchical irqdomain rework, but invoking set_affinity() with force=true stayed and had no side effects. At some point in the past, the force flag got repurposed to support the exynos timer interrupt affinity setting to a not yet online CPU, so the interrupt controller callback does not verify the supplied affinity mask against cpu_online_mask. Setting the flag in the CPU hotplug code causes the cpu online masking to be blocked on these irq controllers and results in potentially affining an interrupt to the CPU which is unplugged, i.e. instead of moving it away, it's just reassigned to it. As the force flags is not longer needed on x86, it's safe to revert that patch so the ARM irqchips which use the force flag work again. Add comments to that effect, so this won't happen again. Note: The online mask handling should be done in the generic code and the force flag and the masking in the irq chips removed all together, but that's not a change possible for 4.13. Fixes: 77f85e66aa8b ("genirq/cpuhotplug: Set force affinity flag on hotplug migration") Reported-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: LAK <linux-arm-kernel@lists.infradead.org> Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1707271217590.3109@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-07-17genirq/PM: Properly pretend disabled state when force resuming interruptsJuergen Gross3-10/+12
Interrupts with the IRQF_FORCE_RESUME flag set have also the IRQF_NO_SUSPEND flag set. They are not disabled in the suspend path, but must be forcefully resumed. That's used by XEN to keep IPIs enabled beyond the suspension of device irqs. Force resume works by pretending that the interrupt was disabled and then calling __irq_enable(). Incrementing the disabled depth counter was enough to do that, but with the recent changes which use state flags to avoid unnecessary hardware access, this is not longer sufficient. If the state flags are not set, then the hardware callbacks are not invoked and the interrupt line stays disabled in "hardware". Set the disabled and masked state when pretending that an interrupt got disabled by suspend. Fixes: bf22ff45bed6 ("genirq: Avoid unnecessary low level irq function calls") Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: xen-devel@lists.xenproject.org Cc: boris.ostrovsky@oracle.com Link: http://lkml.kernel.org/r/20170717174703.4603-2-jgross@suse.com
2017-07-17Merge branch 'irq-urgent-for-linus' of ↵Linus Torvalds1-10/+53
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fix from Thomas Gleixner: "Fix the fallout from reworking the locking and resource management in request/free_irq()" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq: Keep chip buslock across irq_request/release_resources()
2017-07-12genirq: Keep chip buslock across irq_request/release_resources()Thomas Gleixner1-10/+53
Moving the irq_request/release_resources() callbacks out of the spinlocked, irq disabled and bus locked region, unearthed an interesting abuse of the irq_bus_lock/irq_bus_sync_unlock() callbacks. The OMAP GPIO driver does merily power management inside of them. The irq_request_resources() callback of this GPIO irqchip calls a function which reads a GPIO register. That read aborts now because the clock of the GPIO block is not magically enabled via the irq_bus_lock() callback. Move the callbacks under the bus lock again to prevent this. In the free_irq() path this requires to drop the bus_lock before calling synchronize_irq() and reaquiring it before calling the irq_release_resources() callback. The bus lock can't be held because: 1) The data which has been changed between bus_lock/un_lock is cached in the irq chip driver private data and needs to go out to the irq chip via the slow bus (usually SPI or I2C) before calling synchronize_irq(). That's the reason why this bus_lock/unlock magic exists in the first place, as you cannot do SPI/I2C transactions while holding desc->lock with interrupts disabled. 2) synchronize_irq() will actually deadlock, if there is a handler on flight. These chips use threaded handlers for obvious reasons, as they allow to do SPI/I2C communication. When the threaded handler returns then bus_lock needs to be taken in irq_finalize_oneshot() as we need to talk to the actual irq chip once more. After that the threaded handler is marked done, which makes synchronize_irq() return. So if we hold bus_lock accross the synchronize_irq() call, the handler cannot mark itself done because it blocks on the bus lock. That in turn makes synchronize_irq() wait forever on the threaded handler to complete.... Add the missing unlock of desc->request_mutex in the error path of __free_irq() and add a bunch of comments to explain the locking and protection rules. Fixes: 46e48e257360 ("genirq: Move irq resource handling out of spinlocked region") Reported-and-tested-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk> Reported-and-tested-by: Tony Lindgren <tony@atomide.com> Reported-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Not-longer-ranted-at-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Grygorii Strashko <grygorii.strashko@ti.com> Cc: Marc Zyngier <marc.zyngier@arm.com>
2017-07-09Merge branch 'irq-urgent-for-linus' of ↵Linus Torvalds5-26/+62
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fixes from Thomas Gleixner: - A few fixes mopping up the fallout of the big irq overhaul - Move the interrupt resource management logic out of the spin locked, irq disabled region to avoid unnecessary restrictions of the resource callbacks - Preparation for reworking the per cpu irq request function. * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqdomain: Allow ACPI device nodes to be used as irqdomain identifiers genirq/debugfs: Remove redundant NULL pointer check genirq: Allow to pass the IRQF_TIMER flag with percpu irq request genirq/timings: Move free timings out of spinlocked region genirq: Move irq resource handling out of spinlocked region genirq: Add mutex to irq desc to serialize request/free_irq() genirq: Move bus locking into __setup_irq() genirq: Force inlining of __irq_startup_managed to prevent build failure genirq/debugfs: Fix build for !CONFIG_IRQ_DOMAIN
2017-07-08Merge tag 'pci-v4.13-changes' of ↵Linus Torvalds1-1/+12
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: - add sysfs max_link_speed/width, current_link_speed/width (Wong Vee Khee) - make host bridge IRQ mapping much more generic (Matthew Minter, Lorenzo Pieralisi) - convert most drivers to pci_scan_root_bus_bridge() (Lorenzo Pieralisi) - mutex sriov_configure() (Jakub Kicinski) - mutex pci_error_handlers callbacks (Christoph Hellwig) - split ->reset_notify() into ->reset_prepare()/reset_done() (Christoph Hellwig) - support multiple PCIe portdrv interrupts for MSI as well as MSI-X (Gabriele Paoloni) - allocate MSI/MSI-X vector for Downstream Port Containment (Gabriele Paoloni) - fix MSI IRQ affinity pre/post/min_vecs issue (Michael Hernandez) - test INTx masking during enumeration, not at run-time (Piotr Gregor) - avoid using device_may_wakeup() for runtime PM (Rafael J. Wysocki) - restore the status of PCI devices across hibernation (Chen Yu) - keep parent resources that start at 0x0 (Ard Biesheuvel) - enable ECRC only if device supports it (Bjorn Helgaas) - restore PRI and PASID state after Function-Level Reset (CQ Tang) - skip DPC event if device is not present (Keith Busch) - check domain when matching SMBIOS info (Sujith Pandel) - mark Intel XXV710 NIC INTx masking as broken (Alex Williamson) - avoid AMD SB7xx EHCI USB wakeup defect (Kai-Heng Feng) - work around long-standing Macbook Pro poweroff issue (Bjorn Helgaas) - add Switchtec "running" status flag (Logan Gunthorpe) - fix dra7xx incorrect RW1C IRQ register usage (Arvind Yadav) - modify xilinx-nwl IRQ chip for legacy interrupts (Bharat Kumar Gogada) - move VMD SRCU cleanup after bus, child device removal (Jon Derrick) - add Faraday clock handling (Linus Walleij) - configure Rockchip MPS and reorganize (Shawn Lin) - limit Qualcomm TLP size to 2K (hardware issue) (Srinivas Kandagatla) - support Tegra MSI 64-bit addressing (Thierry Reding) - use Rockchip normal (not privileged) register bank (Shawn Lin) - add HiSilicon Kirin SoC PCIe controller driver (Xiaowei Song) - add Sigma Designs Tango SMP8759 PCIe controller driver (Marc Gonzalez) - add MediaTek PCIe host controller support (Ryder Lee) - add Qualcomm IPQ4019 support (John Crispin) - add HyperV vPCI protocol v1.2 support (Jork Loeser) - add i.MX6 regulator support (Quentin Schulz) * tag 'pci-v4.13-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (113 commits) PCI: tango: Add Sigma Designs Tango SMP8759 PCIe host bridge support PCI: Add DT binding for Sigma Designs Tango PCIe controller PCI: rockchip: Use normal register bank for config accessors dt-bindings: PCI: Add documentation for MediaTek PCIe PCI: Remove __pci_dev_reset() and pci_dev_reset() PCI: Split ->reset_notify() method into ->reset_prepare() and ->reset_done() PCI: xilinx: Make of_device_ids const PCI: xilinx-nwl: Modify IRQ chip for legacy interrupts PCI: vmd: Move SRCU cleanup after bus, child device removal PCI: vmd: Correct comment: VMD domains start at 0x10000, not 0x1000 PCI: versatile: Add local struct device pointers PCI: tegra: Do not allocate MSI target memory PCI: tegra: Support MSI 64-bit addressing PCI: rockchip: Use local struct device pointer consistently PCI: rockchip: Check for clk_prepare_enable() errors during resume MAINTAINERS: Remove Wenrui Li as Rockchip PCIe driver maintainer PCI: rockchip: Configure RC's MPS setting PCI: rockchip: Reconfigure configuration space header type PCI: rockchip: Split out rockchip_pcie_cfg_configuration_accesses() PCI: rockchip: Move configuration accesses into rockchip_pcie_cfg_atu() ...
2017-07-07irqdomain: Allow ACPI device nodes to be used as irqdomain identifiersMarc Zyngier1-0/+16
A number of irqchip implementations are (ab)using the irqdomain allocator by passing a fwnode that is neither a FWNODE_OF or a FWNODE_IRQCHIP. This is pretty bad, but it also feels pretty crap to force these drivers to allocate their own irqchip_fwid when they already have a proper fwnode. Instead, let's teach the irqdomain allocator about ACPI device nodes, and add some lovely name generation code... Tested on an arm64 D05 system. Reported-and-tested-by: John Garry <john.garry@huawei.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Agustin Vega-Frias <agustinv@codeaurora.org> Cc: Ma Jun <majun258@huawei.com> Cc: Hanjun Guo <hanjun.guo@linaro.org> Link: http://lkml.kernel.org/r/20170707083959.10349-1-marc.zyngier@arm.com
2017-07-07genirq/debugfs: Remove redundant NULL pointer checkThomas Gleixner1-2/+1
debugfs_remove() can be called with a NULL pointer. Fixes: 087cdfb662ae5 ("genirq/debugfs: Add proper debugfs interface") Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-07-06genirq: Allow to pass the IRQF_TIMER flag with percpu irq requestDaniel Lezcano1-5/+10
The irq timings infrastructure tracks when interrupts occur in order to statistically predict te next interrupt event. There is no point to track timer interrupts and try to predict them because the next expiration time is already known. This can be avoided via the IRQF_TIMER flag which is passed by timer drivers in request_irq(). It marks the interrupt as timer based which alloes to ignore these interrupts in the timings code. Per CPU interrupts which are requested via request_percpu_+irq() have no flag argument, so marking per cpu timer interrupts is not possible and they get tracked pointlessly. Add __request_percpu_irq() as a variant of request_percpu_irq() with a flags argument and make request_percpu_irq() an inline wrapper passing flags = 0. The flag parameter is restricted to IRQF_TIMER as all other IRQF_ flags make no sense for per cpu interrupts. The next step is to convert all existing users of request_percpu_irq() and then remove the wrapper and the underscores. [ tglx: Massaged changelog ] Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: peterz@infradead.org Cc: nicolas.pitre@linaro.org Cc: vincent.guittot@linaro.org Cc: rafael@kernel.org Link: http://lkml.kernel.org/r/1499344144-3964-1-git-send-email-daniel.lezcano@linaro.org
2017-07-04genirq/timings: Move free timings out of spinlocked regionThomas Gleixner1-2/+3
No point to do memory management from a interrupt disabled spin locked region. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Heiko Stuebner <heiko@sntech.de> Cc: Julia Cartwright <julia@ni.com> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Brian Norris <briannorris@chromium.org> Cc: Doug Anderson <dianders@chromium.org> Cc: linux-rockchip@lists.infradead.org Cc: John Keeping <john@metanate.com> Cc: linux-gpio@vger.kernel.org Link: http://lkml.kernel.org/r/20170629214344.196130646@linutronix.de
2017-07-04genirq: Move irq resource handling out of spinlocked regionThomas Gleixner1-8/+15
Aside of being conceptually wrong, there is also an actual (hard to trigger and mostly theoretical) problem. CPU0 CPU1 free_irq(X) interrupt X spin_lock(desc->lock) wake irq thread() spin_unlock(desc->lock) spin_lock(desc->lock) remove action() shutdown_irq() release_resources() thread_handler() spin_unlock(desc->lock) access released resources. synchronize_irq() Move the release resources invocation after synchronize_irq() so it's guaranteed that the threaded handler has finished. Move the resource request call out of the desc->lock held region as well, so the invocation context is the same for both request and release. This solves the problems with those functions on RT as well. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Heiko Stuebner <heiko@sntech.de> Cc: Julia Cartwright <julia@ni.com> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Brian Norris <briannorris@chromium.org> Cc: Doug Anderson <dianders@chromium.org> Cc: linux-rockchip@lists.infradead.org Cc: John Keeping <john@metanate.com> Cc: linux-gpio@vger.kernel.org Link: http://lkml.kernel.org/r/20170629214344.117028181@linutronix.de
2017-07-04genirq: Add mutex to irq desc to serialize request/free_irq()Thomas Gleixner2-0/+9
The irq_request/release_resources() callbacks ar currently invoked under desc->lock with interrupts disabled. This is a source of problems on RT and conceptually not required. Add a seperate mutex to struct irq_desc which allows to serialize request/free_irq(), which can be used to move the resource functions out of the desc->lock held region. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Heiko Stuebner <heiko@sntech.de> Cc: Julia Cartwright <julia@ni.com> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Brian Norris <briannorris@chromium.org> Cc: Doug Anderson <dianders@chromium.org> Cc: linux-rockchip@lists.infradead.org Cc: John Keeping <john@metanate.com> Cc: linux-gpio@vger.kernel.org Link: http://lkml.kernel.org/r/20170629214344.039220922@linutronix.de
2017-07-04genirq: Move bus locking into __setup_irq()Thomas Gleixner1-8/+5
There is no point in having the irq_bus_lock() protection around all callers to __setup_irq(). Move it into __setup_irq(). This is also a preparatory patch for addressing the issues with the irq resource callbacks. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Heiko Stuebner <heiko@sntech.de> Cc: Julia Cartwright <julia@ni.com> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Brian Norris <briannorris@chromium.org> Cc: Doug Anderson <dianders@chromium.org> Cc: linux-rockchip@lists.infradead.org Cc: John Keeping <john@metanate.com> Cc: linux-gpio@vger.kernel.org Link: http://lkml.kernel.org/r/20170629214343.960949031@linutronix.de
2017-07-04genirq: Force inlining of __irq_startup_managed to prevent build failureGeert Uytterhoeven1-1/+1
If CONFIG_SMP=n, and gcc (e.g. 4.1.2) decides not to inline __irq_startup_managed(), the build fails with: kernel/built-in.o: In function `irq_startup': (.text+0x38ed8): undefined reference to `irq_set_affinity_locked' Fix this by forcing inlining of __irq_startup_managed(). Fixes: 761ea388e8c4e3ac ("genirq: Handle managed irqs gracefully in irq_startup()") Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Arnd Bergmann <arnd@arndb.de> Link: http://lkml.kernel.org/r/1499162761-12398-1-git-send-email-geert@linux-m68k.org
2017-07-04genirq/debugfs: Fix build for !CONFIG_IRQ_DOMAINSebastian Ott1-1/+3
Fix this build error: kernel/irq/internals.h:440:20: error: inlining failed in call to always_inline 'irq_domain_debugfs_init': function body not available kernel/irq/debugfs.c:202:2: note: called from here irq_domain_debugfs_init(root_dir); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/alpine.LFD.2.20.1707041124000.1712@schleppi
2017-07-03Merge tag 'docs-4.13' of git://git.lwn.net/linuxLinus Torvalds3-3/+3
Pull documentation updates from Jonathan Corbet: "There has been a fair amount of activity in the docs tree this time around. Highlights include: - Conversion of a bunch of security documentation into RST - The conversion of the remaining DocBook templates by The Amazing Mauro Machine. We can now drop the entire DocBook build chain. - The usual collection of fixes and minor updates" * tag 'docs-4.13' of git://git.lwn.net/linux: (90 commits) scripts/kernel-doc: handle DECLARE_HASHTABLE Documentation: atomic_ops.txt is core-api/atomic_ops.rst Docs: clean up some DocBook loose ends Make the main documentation title less Geocities Docs: Use kernel-figure in vidioc-g-selection.rst Docs: fix table problems in ras.rst Docs: Fix breakage with Sphinx 1.5 and upper Docs: Include the Latex "ifthen" package doc/kokr/howto: Only send regression fixes after -rc1 docs-rst: fix broken links to dynamic-debug-howto in kernel-parameters doc: Document suitability of IBM Verse for kernel development Doc: fix a markup error in coding-style.rst docs: driver-api: i2c: remove some outdated information Documentation: DMA API: fix a typo in a function name Docs: Insert missing space to separate link from text doc/ko_KR/memory-barriers: Update control-dependencies example Documentation, kbuild: fix typo "minimun" -> "minimum" docs: Fix some formatting issues in request-key.rst doc: ReSTify keys-trusted-encrypted.txt doc: ReSTify keys-request-key.txt ...
2017-06-26genirq: Avoid unnecessary low level irq function callsJeffy Chen1-20/+33
Check irq state in enable/disable/unmask/mask_irq to avoid unnecessary low level irq function calls. This has two advantages: - Conditionals are faster than hardware access - Solves issues with the underlying refcounting of the pinctrl infrastructure Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: tfiga@chromium.org Cc: briannorris@chromium.org Cc: dianders@chromium.org Link: http://lkml.kernel.org/r/1498476814-12563-2-git-send-email-jeffy.chen@rock-chips.com
2017-06-26genirq: Set irq masked state when initializing irq_descJeffy Chen1-0/+1
The irq default state is set to disabled when allocating irq desc, but the masked state flag is not set. This is inconsistent vs. the state tracking logic which is used to prevent unnecessary calls to hardware level irq chip functions. Set the masked state flag as well. Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: tfiga@chromium.org Cc: briannorris@chromium.org Cc: dianders@chromium.org Link: http://lkml.kernel.org/r/1498476814-12563-1-git-send-email-jeffy.chen@rock-chips.com
2017-06-24genirq/timings: Add infrastructure for estimating the next interrupt arrival ↵Daniel Lezcano2-0/+358
time An interrupt behaves with a burst of activity with periodic interval of time followed by one or two peaks of longer interval. As the time intervals are periodic, statistically speaking they follow a normal distribution and each interrupts can be tracked individually. Add a mechanism to compute the statistics on all interrupts, except the timers which are deterministic from a prediction point of view, as their expiry time is known. The goal is to extract the periodicity for each interrupt, with the last timestamp and sum them, so the next event can be predicted to a certain extent. Taking the earliest prediction gives the expected wakeup on the system (assuming a timer won't expire before). Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Nicolas Pitre <nicolas.pitre@linaro.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Hannes Reinecke <hare@suse.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: "Rafael J . Wysocki" <rafael@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Link: http://lkml.kernel.org/r/1498227072-5980-2-git-send-email-daniel.lezcano@linaro.org
2017-06-24genirq/timings: Add infrastructure to track the interrupt timingsDaniel Lezcano6-0/+129
The interrupt framework gives a lot of information about each interrupt. It does not keep track of when those interrupts occur though, which is a prerequisite for estimating the next interrupt arrival for power management purposes. Add a mechanism to record the timestamp for each interrupt occurrences in a per-CPU circular buffer to help with the prediction of the next occurrence using a statistical model. Each CPU can store up to IRQ_TIMINGS_SIZE events <irq, timestamp>, the current value of IRQ_TIMINGS_SIZE is 32. Each event is encoded into a single u64, where the high 48 bits are used for the timestamp and the low 16 bits are for the irq number. A static key is introduced so when the irq prediction is switched off at runtime, the overhead is near to zero. It results in most of the code in internals.h for inline reasons and a very few in the new file timings.c. The latter will contain more in the next patch which will provide the statistical model for the next event prediction. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Hannes Reinecke <hare@suse.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: "Rafael J . Wysocki" <rafael@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Link: http://lkml.kernel.org/r/1498227072-5980-1-git-send-email-daniel.lezcano@linaro.org
2017-06-24genirq/debugfs: Remove pointless NULL pointer checkThomas Gleixner2-8/+6
debugfs_remove() has it's own NULL pointer check. Remove the conditional and make irq_remove_debugfs_entry() an inline helper Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-06-22genirq/irqdomain: Remove auto-recursive hierarchy supportMarc Zyngier2-43/+14
It did seem like a good idea at the time, but it never really caught on, and auto-recursive domains remain unused 3 years after having been introduced. Oh well, time for a late spring cleanup. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-06-22genirq/irqdomain: Add irq_domain_update_bus_token helperMarc Zyngier1-0/+31
We can have irq domains that are identified by the same fwnode (because they are serviced by the same HW), and yet have different functionnality (because they serve different busses, for example). This is what we use the bus_token field. Since we don't use this field when generating the domain name, all the aliasing domains will get the same name, and the debugfs file creation fails. Also, bus_token is updated by individual drivers, and the core code is unaware of that update. In order to sort this mess, let's introduce a helper that takes care of updating bus_token, and regenerate the debugfs file. A separate patch will update all the individual users. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-06-22genirq/affinity: Assign vectors to all present CPUsChristoph Hellwig1-13/+63
Currently the irq vector spread algorithm is restricted to online CPUs, which ties the IRQ mapping to the currently online devices and doesn't deal nicely with the fact that CPUs could come and go rapidly due to e.g. power management. Instead assign vectors to all present CPUs to avoid this churn. Build a map of all possible CPUs for a given node, as the architectures only provide a map of all onlines CPUs. Do this dynamically on each call for the vector assingments, which is a bit suboptimal and could be optimized in the future by provinding a mapping from the arch code. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-block@vger.kernel.org Cc: Sagi Grimberg <sagi@grimberg.me> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: linux-nvme@lists.infradead.org Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20170603140403.27379-5-hch@lst.de
2017-06-22genirq/cpuhotplug: Avoid irq affinity setting for single targetsThomas Gleixner1-2/+10
Avoid trying to add a newly online CPU to the effective affinity mask of an started up interrupt. That interrupt will either stay on the already online CPU or move around for no value. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235447.431321047@linutronix.de
2017-06-22genirq: Introduce IRQD_SINGLE_TARGET flagThomas Gleixner1-0/+1
Many interrupt chips allow only a single CPU as interrupt target. The core code has no knowledge about that. That's unfortunate as it could avoid trying to readd a newly online CPU to the effective affinity mask. Add the status flag and the necessary accessors. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235447.352343969@linutronix.de
2017-06-22genirq/cpuhotplug: Handle managed IRQs on CPU hotplugThomas Gleixner1-0/+45
If a CPU goes offline, interrupts affine to the CPU are moved away. If the outgoing CPU is the last CPU in the affinity mask the migration code breaks the affinity and sets it it all online cpus. This is a problem for affinity managed interrupts as CPU hotplug is often used for power management purposes. If the affinity is broken, the interrupt is not longer affine to the CPUs to which it was allocated. The affinity spreading allows to lay out multi queue devices in a way that they are assigned to a single CPU or a group of CPUs. If the last CPU goes offline, then the queue is not longer used, so the interrupt can be shutdown gracefully and parked until one of the assigned CPUs comes online again. Add a graceful shutdown mechanism into the irq affinity breaking code path, mark the irq as MANAGED_SHUTDOWN and leave the affinity mask unmodified. In the online path, scan the active interrupts for managed interrupts and if the interrupt is functional and the newly online CPU is part of the affinity mask, restart the interrupt if it is marked MANAGED_SHUTDOWN or if the interrupts is started up, try to add the CPU back to the effective affinity mask. Originally-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20170619235447.273417334@linutronix.de
2017-06-22genirq: Handle managed irqs gracefully in irq_startup()Thomas Gleixner1-3/+61
Affinity managed interrupts should keep their assigned affinity accross CPU hotplug. To avoid magic hackery in device drivers, the core code shall manage them transparently and set these interrupts into a managed shutdown state when the last CPU of the assigned affinity mask goes offline. The interrupt will be restarted when one of the CPUs in the assigned affinity mask comes back online. Add the necessary logic to irq_startup(). If an interrupt is requested and started up, the code checks whether it is affinity managed and if so, it checks whether a CPU in the interrupts affinity mask is online. If not, it puts the interrupt into managed shutdown state. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235447.189851170@linutronix.de
2017-06-22genirq: Add force argument to irq_startup()Thomas Gleixner4-7/+14
In order to handle managed interrupts gracefully on irq_startup() so they won't lose their assigned affinity, it's necessary to allow startups which keep the interrupts in managed shutdown state, if none of the assigend CPUs is online. This allows drivers to request interrupts w/o the CPUs being online, which avoid online/offline churn in drivers. Add a force argument which can override that decision and let only request_irq() and enable_irq() allow the managed shutdown handling. enable_irq() is required, because the interrupt might be requested with IRQF_NOAUTOEN and enable_irq() invokes irq_startup() which would then wreckage the assignment again. All other callers force startup and potentially break the assigned affinity. No functional change as this only adds the function argument. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235447.112094565@linutronix.de
2017-06-22genirq: Split out irq_startup() codeThomas Gleixner1-11/+18
Split out the inner workings of irq_startup() so it can be reused to handle managed interrupts gracefully. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235447.033235144@linutronix.de
2017-06-22genirq: Introduce IRQD_MANAGED_SHUTDOWNThomas Gleixner1-0/+10
Affinity managed interrupts should keep their assigned affinity accross CPU hotplug. To avoid magic hackery in device drivers, the core code shall manage them transparently. This will set these interrupts into a managed shutdown state when the last CPU of the assigned affinity mask goes offline. The interrupt will be restarted when one of the CPUs in the assigned affinity mask comes back online. Introduce the necessary state flag and the accessor functions. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235446.954523476@linutronix.de
2017-06-22genirq/cpuhotplug: Use effective affinity maskThomas Gleixner1-3/+11
If the architecture supports the effective affinity mask, migrating interrupts away which are not targeted by the effective mask is pointless. They can stay in the user or system supplied affinity mask, but won't be targetted at any given point as the affinity setter functions need to validate against the online cpu mask anyway. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235446.328488490@linutronix.de
2017-06-22genirq: Introduce effective affinity maskThomas Gleixner4-7/+105
There is currently no way to evaluate the effective affinity mask of a given interrupt. Many irq chips allow only a single target CPU or a subset of CPUs in the affinity mask. Updating the mask at the time of setting the affinity to the subset would be counterproductive because information for cpu hotplug about assigned interrupt affinities gets lost. On CPU hotplug it's also pointless to force migrate an interrupt, which is not targeted at the CPU effectively. But currently the information is not available. Provide a seperate mask to be updated by the irq_chip->irq_set_affinity() implementations. Implement the read only proc files so the user can see the effective mask as well w/o trying to deduce it from /proc/interrupts. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235446.247834245@linutronix.de
2017-06-22genirq/proc: Replace ever repeating type castThomas Gleixner1-5/+5
The proc file setup repeats the same ugly type cast for the irq number over and over. Do it once and hand in the local void pointer. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235446.160866358@linutronix.de
2017-06-22genirq: Remove pointless gfp argumentThomas Gleixner1-8/+7
All callers hand in GPF_KERNEL. No point to have an extra argument for that. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235446.082544752@linutronix.de
2017-06-22genirq: Remove pointless arg from show_irq_affinityThomas Gleixner1-3/+3
The third argument of the internal helper function is unused. Remove it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235446.004958600@linutronix.de
2017-06-22genirq: Move irq_fixup_move_pending() to coreThomas Gleixner1-0/+5
Now that x86 uses the generic code, the function declaration and inline stub can move to the core internal header. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235445.928156166@linutronix.de
2017-06-22genirq/cpuhotplug: Set force affinity flag on hotplug migrationThomas Gleixner1-1/+1
Set the force migration flag when migrating interrupts away from an outgoing CPU. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235445.681874648@linutronix.de
2017-06-22genirq/cpuhotplug: Add support for conditional maskingThomas Gleixner1-1/+10
Interrupts which cannot be migrated in process context, need to be masked before the affinity is changed forcefully. Add support for that. Will be compiled out for architectures which do not have this x86 specific issue. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235445.604565591@linutronix.de
2017-06-22genirq/cpuhotplug: Add support for cleaning up move in progressThomas Gleixner2-3/+35
In order to move x86 to the generic hotplug migration code, add support for cleaning up move in progress bits. On architectures which have this x86 specific (mis)feature not enabled, this is optimized out by the compiler. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235445.525817311@linutronix.de
2017-06-22genirq/cpuhotplug: Do not migrated shutdown irqsThomas Gleixner1-3/+8
Interrupts, which are shut down are tried to be migrated as well. That's pointless because the interrupt cannot fire and the next startup will move it to the proper place anyway. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235445.447550992@linutronix.de
2017-06-22genirq/cpuhotplug: Reorder check logicThomas Gleixner1-16/+20
Move the checks for a valid irq chip and the irq_set_affinity() callback right in front of the whole migration logic. No point in doing a gazillion of other things when the interrupt cannot be migrated at all. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235445.354181630@linutronix.de
2017-06-22genirq/cpuhotplug: Dont claim success on errorThomas Gleixner1-1/+4
In case the affinity of an interrupt was broken, a printk is emitted. But if the affinity cannot be set at all due to a missing irq_set_affinity() callback or due to a failing callback, the message is still printed preceeded by a warning/error. That makes no sense whatsoever. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235445.274852976@linutronix.de
2017-06-22genirq/cpuhotplug: Remove irq disabling logicThomas Gleixner1-8/+4
This is called from stop_machine() with interrupts disabled. No point in disabling them some more. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235445.198042748@linutronix.de
2017-06-22genirq: Move pending helpers to internal.hChristoph Hellwig2-28/+38
So that the affinity code can reuse them. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20170619235445.109426284@linutronix.de
2017-06-22genirq: Move initial affinity setup to irq_startup()Thomas Gleixner2-9/+8
The startup vs. setaffinity ordering of interrupts depends on the IRQF_NOAUTOEN flag. Chained interrupts are not getting any affinity assignment at all. A regular interrupt is started up and then the affinity is set. A IRQF_NOAUTOEN marked interrupt is not started up, but the affinity is set nevertheless. Move the affinity setup to startup_irq() so the ordering is always the same and chained interrupts get the proper default affinity assigned as well. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235445.020534783@linutronix.de
2017-06-22genirq: Rename setup_affinity() to irq_setup_affinity()Thomas Gleixner2-6/+7
Rename it with a proper irq_ prefix and make it available for other files in the core code. Preparatory patch for moving the irq affinity setup around. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235444.928501004@linutronix.de
2017-06-22genirq: Remove mask argument from setup_affinity()Thomas Gleixner3-34/+29
No point to have this alloc/free dance of cpumasks. Provide a static mask for setup_affinity() and protect it proper. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235444.851571573@linutronix.de