kernel/linux.git/include/linux/cpuhotplug.h, branch v4.14.223

clocksource/drivers/exynos_mct: Increase priority over ARM arch timer

2019-07-31T05:28:30+00:00

[ Upstream commit 6282edb72bed5324352522d732080d4c1b9dfed6 ] Exynos SoCs based on CA7/CA15 have 2 timer interfaces: custom Exynos MCT (Multi Core Timer) and standard ARM Architected Timers. There are use cases, where both timer interfaces are used simultanously. One of such examples is using Exynos MCT for the main system timer and ARM Architected Timers for the KVM and virtualized guests (KVM requires arch timers). Exynos Multi-Core Timer driver (exynos_mct) must be however started before ARM Architected Timers (arch_timer), because they both share some common hardware blocks (global system counter) and turning on MCT is needed to get ARM Architected Timer working properly. To ensure selecting Exynos MCT as the main system timer, increase MCT timer rating. To ensure proper starting order of both timers during suspend/resume cycle, increase MCT hotplug priority over ARM Archictected Timers. Signed-off-by: Marek Szyprowski Reviewed-by: Krzysztof Kozlowski Reviewed-by: Chanwoo Choi Signed-off-by: Daniel Lezcano Signed-off-by: Sasha Levin

drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT

2019-07-21T07:04:16+00:00

commit 83b44fe343b5abfcb1b2261289bd0cfcfcfd60a8 upstream. The cacheinfo structures are alloced/freed by cpu online/offline callbacks. Originally these were only used by sysfs to expose the cache topology to user space. Without any in-kernel dependencies CPUHP_AP_ONLINE_DYN was an appropriate choice. resctrl has started using these structures to identify CPUs that share a cache. It updates its 'domain' structures from cpu online/offline callbacks. These depend on the cacheinfo structures (resctrl_online_cpu()->domain_add_cpu()->get_cache_id()-> get_cpu_cacheinfo()). These also run as CPUHP_AP_ONLINE_DYN. Now that there is an in-kernel dependency, move the cacheinfo work earlier so we know its done before resctrl's CPUHP_AP_ONLINE_DYN work runs. Fixes: 2264d9c74dda1 ("x86/intel_rdt: Build structures for each resource based on cache topology") Cc: Cc: Fenghua Yu Cc: Reinette Chatre Signed-off-by: James Morse Link: https://lore.kernel.org/r/20190624173656.202407-1-james.morse@arm.com Signed-off-by: Greg Kroah-Hartman

x86/microcode, cpuhotplug: Add a microcode loader CPU hotplug callback

2019-06-19T06:20:59+00:00

commit 78f4e932f7760d965fb1569025d1576ab77557c5 upstream. Adric Blake reported the following warning during suspend-resume: Enabling non-boot CPUs ... x86: Booting SMP configuration: smpboot: Booting Node 0 Processor 1 APIC 0x2 unchecked MSR access error: WRMSR to 0x10f (tried to write 0x0000000000000000) \ at rIP: 0xffffffff8d267924 (native_write_msr+0x4/0x20) Call Trace: intel_set_tfa intel_pmu_cpu_starting ? x86_pmu_dead_cpu x86_pmu_starting_cpu cpuhp_invoke_callback ? _raw_spin_lock_irqsave notify_cpu_starting start_secondary secondary_startup_64 microcode: sig=0x806ea, pf=0x80, revision=0x96 microcode: updated to revision 0xb4, date = 2019-04-01 CPU1 is up The MSR in question is MSR_TFA_RTM_FORCE_ABORT and that MSR is emulated by microcode. The log above shows that the microcode loader callback happens after the PMU restoration, leading to the conjecture that because the microcode hasn't been updated yet, that MSR is not present yet, leading to the #GP. Add a microcode loader-specific hotplug vector which comes before the PERF vectors and thus executes earlier and makes sure the MSR is present. Fixes: 400816f60c54 ("perf/x86/intel: Implement support for TSX Force Abort") Reported-by: Adric Blake Signed-off-by: Borislav Petkov Reviewed-by: Thomas Gleixner Cc: Peter Zijlstra Cc: Cc: x86@kernel.org Link: https://bugzilla.kernel.org/show_bug.cgi?id=203637 Signed-off-by: Greg Kroah-Hartman

timers: Reinitialize per cpu bases on hotplug

2018-01-02T19:31:15+00:00

commit 26456f87aca7157c057de65c9414b37f1ab881d1 upstream. The timer wheel bases are not (re)initialized on CPU hotplug. That leaves them with a potentially stale clk and next_expiry valuem, which can cause trouble then the CPU is plugged. Add a prepare callback which forwards the clock, sets next_expiry to far in the future and reset the control flags to a known state. Set base->must_forward_clk so the first timer which is queued will try to forward the clock to current jiffies. Fixes: 500462a9de65 ("timers: Switch to a non-cascading wheel") Reported-by: Paul E. McKenney Signed-off-by: Thomas Gleixner Cc: Peter Zijlstra Cc: Frederic Weisbecker Cc: Sebastian Siewior Cc: Anna-Maria Gleixner Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1712272152200.2431@nanos Signed-off-by: Greg Kroah-Hartman

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55+00:00

Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

smp/hotplug: Hotplug state fail injection

2017-09-25T20:11:44+00:00

Add a sysfs file to one-time fail a specific state. This can be used to test the state rollback code paths. Something like this (hotplug-up.sh): #!/bin/bash echo 0 > /debug/sched_debug echo 1 > /debug/tracing/events/cpuhp/enable ALL_STATES=`cat /sys/devices/system/cpu/hotplug/states | cut -d':' -f1` STATES=${1:-$ALL_STATES} for state in $STATES do echo 0 > /sys/devices/system/cpu/cpu1/online echo 0 > /debug/tracing/trace echo Fail state: $state echo $state > /sys/devices/system/cpu/cpu1/hotplug/fail cat /sys/devices/system/cpu/cpu1/hotplug/fail echo 1 > /sys/devices/system/cpu/cpu1/online cat /debug/tracing/trace > hotfail-${state}.trace sleep 1 done Can be used to test for all possible rollback (barring multi-instance) scenarios on CPU-up, CPU-down is a trivial modification of the above. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner Cc: bigeasy@linutronix.de Cc: efault@gmx.de Cc: rostedt@goodmis.org Cc: max.byungchul.park@gmail.com Link: https://lkml.kernel.org/r/20170920170546.972581715@infradead.org

smp/hotplug: Add state diagram

2017-09-25T20:11:41+00:00

Add a state diagram to clarify when which states are ran where. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner Cc: bigeasy@linutronix.de Cc: efault@gmx.de Cc: rostedt@goodmis.org Cc: max.byungchul.park@gmail.com Link: https://lkml.kernel.org/r/20170920170546.661598270@infradead.org

Merge tag 'powerpc-4.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2017-09-07T17:15:40+00:00

Pull powerpc updates from Michael Ellerman: "Nothing really major this release, despite quite a lot of activity. Just lots of things all over the place. Some things of note include: - Access via perf to a new type of PMU (IMC) on Power9, which can count both core events as well as nest unit events (Memory controller etc). - Optimisations to the radix MMU TLB flushing, mostly to avoid unnecessary Page Walk Cache (PWC) flushes when the structure of the tree is not changing. - Reworks/cleanups of do_page_fault() to modernise it and bring it closer to other architectures where possible. - Rework of our page table walking so that THP updates only need to send IPIs to CPUs where the affected mm has run, rather than all CPUs. - The size of our vmalloc area is increased to 56T on 64-bit hash MMU systems. This avoids problems with the percpu allocator on systems with very sparse NUMA layouts. - STRICT_KERNEL_RWX support on PPC32. - A new sched domain topology for Power9, to capture the fact that pairs of cores may share an L2 cache. - Power9 support for VAS, which is a new mechanism for accessing coprocessors, and initial support for using it with the NX compression accelerator. - Major work on the instruction emulation support, adding support for many new instructions, and reworking it so it can be used to implement the emulation needed to fixup alignment faults. - Support for guests under PowerVM to use the Power9 XIVE interrupt controller. And probably that many things again that are almost as interesting, but I had to keep the list short. Plus the usual fixes and cleanups as always. Thanks to: Alexey Kardashevskiy, Alistair Popple, Andreas Schwab, Aneesh Kumar K.V, Anju T Sudhakar, Arvind Yadav, Balbir Singh, Benjamin Herrenschmidt, Bhumika Goyal, Breno Leitao, Bryant G. Ly, Christophe Leroy, Cédric Le Goater, Dan Carpenter, Dou Liyang, Frederic Barrat, Gautham R. Shenoy, Geliang Tang, Geoff Levand, Hannes Reinecke, Haren Myneni, Ivan Mikhaylov, John Allen, Julia Lawall, LABBE Corentin, Laurentiu Tudor, Madhavan Srinivasan, Markus Elfring, Masahiro Yamada, Matt Brown, Michael Neuling, Murilo Opsfelder Araujo, Nathan Fontenot, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Paul Mackerras, Rashmica Gupta, Rob Herring, Rui Teng, Sam Bobroff, Santosh Sivaraj, Scott Wood, Shilpasri G Bhat, Sukadev Bhattiprolu, Suraj Jitindar Singh, Tobin C. Harding, Victor Aoqui" * tag 'powerpc-4.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (321 commits) powerpc/xive: Fix section __init warning powerpc: Fix kernel crash in emulation of vector loads and stores powerpc/xive: improve debugging macros powerpc/xive: add XIVE Exploitation Mode to CAS powerpc/xive: introduce H_INT_ESB hcall powerpc/xive: add the HW IRQ number under xive_irq_data powerpc/xive: introduce xive_esb_write() powerpc/xive: rename xive_poke_esb() in xive_esb_read() powerpc/xive: guest exploitation of the XIVE interrupt controller powerpc/xive: introduce a common routine xive_queue_page_alloc() powerpc/sstep: Avoid used uninitialized error axonram: Return directly after a failed kzalloc() in axon_ram_probe() axonram: Improve a size determination in axon_ram_probe() axonram: Delete an error message for a failed memory allocation in axon_ram_probe() powerpc/powernv/npu: Move tlb flush before launching ATSD powerpc/macintosh: constify wf_sensor_ops structures powerpc/iommu: Use permission-specific DEVICE_ATTR variants powerpc/eeh: Delete an error out of memory message at init time powerpc/mm: Use seq_putc() in two functions macintosh: Convert to using %pOF instead of full_name ...

scsi: bnx2i: Simplify cpu hotplug code

2017-07-27T01:51:25+00:00

The CPU hotplug related code of this driver can be simplified by: 1) Consolidating the callbacks into a single state. The CPU thread can be torn down on the CPU which goes offline. There is no point in delaying that to the CPU dead state 2) Let the core code invoke the online/offline callbacks and remove the extra for_each_online_cpu() loops. Signed-off-by: Thomas Gleixner Acked-by: Chad Dupuis Signed-off-by: Martin K. Petersen

scsi: bnx2fc: Simplify CPU hotplug code

2017-07-27T01:51:25+00:00