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2020-06-02Documentation: kgdboc: Document new kgdboc_earlycon parameterDouglas Anderson1-0/+20
The recent patch ("kgdboc: Add kgdboc_earlycon to support early kgdb using boot consoles") adds a new kernel command line parameter. Document it. Note that the patch adding the feature does some comparing/contrasting of "kgdboc_earlycon" vs. the existing "ekgdboc". See that patch for more details, but briefly "ekgdboc" can be used _instead_ of "kgdboc" and just makes "kgdboc" do its normal initialization early (only works if your tty driver is already ready). The new "kgdboc_earlycon" works in combination with "kgdboc" and is backed by boot consoles. Signed-off-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Link: https://lore.kernel.org/r/20200507130644.v4.9.I7d5eb42c6180c831d47aef1af44d0b8be3fac559@changeid Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2020-06-01Merge tag 'docs-5.8' of git://git.lwn.net/linuxLinus Torvalds12-186/+374
Pull documentation updates from Jonathan Corbet: "A fair amount of stuff this time around, dominated by yet another massive set from Mauro toward the completion of the RST conversion. I *really* hope we are getting close to the end of this. Meanwhile, those patches reach pretty far afield to update document references around the tree; there should be no actual code changes there. There will be, alas, more of the usual trivial merge conflicts. Beyond that we have more translations, improvements to the sphinx scripting, a number of additions to the sysctl documentation, and lots of fixes" * tag 'docs-5.8' of git://git.lwn.net/linux: (130 commits) Documentation: fixes to the maintainer-entry-profile template zswap: docs/vm: Fix typo accept_threshold_percent in zswap.rst tracing: Fix events.rst section numbering docs: acpi: fix old http link and improve document format docs: filesystems: add info about efivars content Documentation: LSM: Correct the basic LSM description mailmap: change email for Ricardo Ribalda docs: sysctl/kernel: document unaligned controls Documentation: admin-guide: update bug-hunting.rst docs: sysctl/kernel: document ngroups_max nvdimm: fixes to maintainter-entry-profile Documentation/features: Correct RISC-V kprobes support entry Documentation/features: Refresh the arch support status files Revert "docs: sysctl/kernel: document ngroups_max" docs: move locking-specific documents to locking/ docs: move digsig docs to the security book docs: move the kref doc into the core-api book docs: add IRQ documentation at the core-api book docs: debugging-via-ohci1394.txt: add it to the core-api book docs: fix references for ipmi.rst file ...
2020-06-01Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linuxLinus Torvalds1-0/+6
Pull arm64 updates from Will Deacon: "A sizeable pile of arm64 updates for 5.8. Summary below, but the big two features are support for Branch Target Identification and Clang's Shadow Call stack. The latter is currently arm64-only, but the high-level parts are all in core code so it could easily be adopted by other architectures pending toolchain support Branch Target Identification (BTI): - Support for ARMv8.5-BTI in both user- and kernel-space. This allows branch targets to limit the types of branch from which they can be called and additionally prevents branching to arbitrary code, although kernel support requires a very recent toolchain. - Function annotation via SYM_FUNC_START() so that assembly functions are wrapped with the relevant "landing pad" instructions. - BPF and vDSO updates to use the new instructions. - Addition of a new HWCAP and exposure of BTI capability to userspace via ID register emulation, along with ELF loader support for the BTI feature in .note.gnu.property. - Non-critical fixes to CFI unwind annotations in the sigreturn trampoline. Shadow Call Stack (SCS): - Support for Clang's Shadow Call Stack feature, which reserves platform register x18 to point at a separate stack for each task that holds only return addresses. This protects function return control flow from buffer overruns on the main stack. - Save/restore of x18 across problematic boundaries (user-mode, hypervisor, EFI, suspend, etc). - Core support for SCS, should other architectures want to use it too. - SCS overflow checking on context-switch as part of the existing stack limit check if CONFIG_SCHED_STACK_END_CHECK=y. CPU feature detection: - Removed numerous "SANITY CHECK" errors when running on a system with mismatched AArch32 support at EL1. This is primarily a concern for KVM, which disabled support for 32-bit guests on such a system. - Addition of new ID registers and fields as the architecture has been extended. Perf and PMU drivers: - Minor fixes and cleanups to system PMU drivers. Hardware errata: - Unify KVM workarounds for VHE and nVHE configurations. - Sort vendor errata entries in Kconfig. Secure Monitor Call Calling Convention (SMCCC): - Update to the latest specification from Arm (v1.2). - Allow PSCI code to query the SMCCC version. Software Delegated Exception Interface (SDEI): - Unexport a bunch of unused symbols. - Minor fixes to handling of firmware data. Pointer authentication: - Add support for dumping the kernel PAC mask in vmcoreinfo so that the stack can be unwound by tools such as kdump. - Simplification of key initialisation during CPU bringup. BPF backend: - Improve immediate generation for logical and add/sub instructions. vDSO: - Minor fixes to the linker flags for consistency with other architectures and support for LLVM's unwinder. - Clean up logic to initialise and map the vDSO into userspace. ACPI: - Work around for an ambiguity in the IORT specification relating to the "num_ids" field. - Support _DMA method for all named components rather than only PCIe root complexes. - Minor other IORT-related fixes. Miscellaneous: - Initialise debug traps early for KGDB and fix KDB cacheflushing deadlock. - Minor tweaks to early boot state (documentation update, set TEXT_OFFSET to 0x0, increase alignment of PE/COFF sections). - Refactoring and cleanup" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (148 commits) KVM: arm64: Move __load_guest_stage2 to kvm_mmu.h KVM: arm64: Check advertised Stage-2 page size capability arm64/cpufeature: Add get_arm64_ftr_reg_nowarn() ACPI/IORT: Remove the unused __get_pci_rid() arm64/cpuinfo: Add ID_MMFR4_EL1 into the cpuinfo_arm64 context arm64/cpufeature: Add remaining feature bits in ID_AA64PFR1 register arm64/cpufeature: Add remaining feature bits in ID_AA64PFR0 register arm64/cpufeature: Add remaining feature bits in ID_AA64ISAR0 register arm64/cpufeature: Add remaining feature bits in ID_MMFR4 register arm64/cpufeature: Add remaining feature bits in ID_PFR0 register arm64/cpufeature: Introduce ID_MMFR5 CPU register arm64/cpufeature: Introduce ID_DFR1 CPU register arm64/cpufeature: Introduce ID_PFR2 CPU register arm64/cpufeature: Make doublelock a signed feature in ID_AA64DFR0 arm64/cpufeature: Drop TraceFilt feature exposure from ID_DFR0 register arm64/cpufeature: Add explicit ftr_id_isar0[] for ID_ISAR0 register arm64: mm: Add asid_gen_match() helper firmware: smccc: Fix missing prototype warning for arm_smccc_version_init arm64: vdso: Fix CFI directives in sigreturn trampoline arm64: vdso: Don't prefix sigreturn trampoline with a BTI C instruction ...
2020-06-01Merge tag 'x86-boot-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-0/+7
Pull x86 boot updates from Ingo Molnar: "Misc updates: - Add the initrdmem= boot option to specify an initrd embedded in RAM (flash most likely) - Sanitize the CS value earlier during boot, which also fixes SEV-ES - Various fixes and smaller cleanups" * tag 'x86-boot-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot: Correct relocation destination on old linkers x86/boot/compressed/64: Switch to __KERNEL_CS after GDT is loaded x86/boot: Fix -Wint-to-pointer-cast build warning x86/boot: Add kstrtoul() from lib/ x86/tboot: Mark tboot static x86/setup: Add an initrdmem= option to specify initrd physical address
2020-06-01Merge tag 'perf-core-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds2-29/+71
Pull perf updates from Ingo Molnar: "Kernel side changes: - Add AMD Fam17h RAPL support - Introduce CAP_PERFMON to kernel and user space - Add Zhaoxin CPU support - Misc fixes and cleanups Tooling changes: - perf record: Introduce '--switch-output-event' to use arbitrary events to be setup and read from a side band thread and, when they take place a signal be sent to the main 'perf record' thread, reusing the core for '--switch-output' to take perf.data snapshots from the ring buffer used for '--overwrite', e.g.: # perf record --overwrite -e sched:* \ --switch-output-event syscalls:*connect* \ workload will take perf.data.YYYYMMDDHHMMSS snapshots up to around the connect syscalls. Add '--num-synthesize-threads' option to control degree of parallelism of the synthesize_mmap() code which is scanning /proc/PID/task/PID/maps and can be time consuming. This mimics pre-existing behaviour in 'perf top'. - perf bench: Add a multi-threaded synthesize benchmark and kallsyms parsing benchmark. - Intel PT support: Stitch LBR records from multiple samples to get deeper backtraces, there are caveats, see the csets for details. Allow using Intel PT to synthesize callchains for regular events. Add support for synthesizing branch stacks for regular events (cycles, instructions, etc) from Intel PT data. Misc changes: - Updated perf vendor events for power9 and Coresight. - Add flamegraph.py script via 'perf flamegraph' - Misc other changes, fixes and cleanups - see the Git log for details Also, since over the last couple of years perf tooling has matured and decoupled from the kernel perf changes to a large degree, going forward Arnaldo is going to send perf tooling changes via direct pull requests" * tag 'perf-core-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (163 commits) perf/x86/rapl: Add AMD Fam17h RAPL support perf/x86/rapl: Make perf_probe_msr() more robust and flexible perf/x86/rapl: Flip logic on default events visibility perf/x86/rapl: Refactor to share the RAPL code between Intel and AMD CPUs perf/x86/rapl: Move RAPL support to common x86 code perf/core: Replace zero-length array with flexible-array perf/x86: Replace zero-length array with flexible-array perf/x86/intel: Add more available bits for OFFCORE_RESPONSE of Intel Tremont perf/x86/rapl: Add Ice Lake RAPL support perf flamegraph: Use /bin/bash for report and record scripts perf cs-etm: Move definition of 'traceid_list' global variable from header file libsymbols kallsyms: Move hex2u64 out of header libsymbols kallsyms: Parse using io api perf bench: Add kallsyms parsing perf: cs-etm: Update to build with latest opencsd version. perf symbol: Fix kernel symbol address display perf inject: Rename perf_evsel__*() operating on 'struct evsel *' to evsel__*() perf annotate: Rename perf_evsel__*() operating on 'struct evsel *' to evsel__*() perf trace: Rename perf_evsel__*() operating on 'struct evsel *' to evsel__*() perf script: Rename perf_evsel__*() operating on 'struct evsel *' to evsel__*() ...
2020-06-01Merge tag 'core-rcu-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-0/+19
Pull RCU updates from Ingo Molnar: "The RCU updates for this cycle were: - RCU-tasks update, including addition of RCU Tasks Trace for BPF use and TASKS_RUDE_RCU - kfree_rcu() updates. - Remove scheduler locking restriction - RCU CPU stall warning updates. - Torture-test updates. - Miscellaneous fixes and other updates" * tag 'core-rcu-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (103 commits) rcu: Allow for smp_call_function() running callbacks from idle rcu: Provide rcu_irq_exit_check_preempt() rcu: Abstract out rcu_irq_enter_check_tick() from rcu_nmi_enter() rcu: Provide __rcu_is_watching() rcu: Provide rcu_irq_exit_preempt() rcu: Make RCU IRQ enter/exit functions rely on in_nmi() rcu/tree: Mark the idle relevant functions noinstr x86: Replace ist_enter() with nmi_enter() x86/mce: Send #MC singal from task work x86/entry: Get rid of ist_begin/end_non_atomic() sched,rcu,tracing: Avoid tracing before in_nmi() is correct sh/ftrace: Move arch_ftrace_nmi_{enter,exit} into nmi exception lockdep: Always inline lockdep_{off,on}() hardirq/nmi: Allow nested nmi_enter() arm64: Prepare arch_nmi_enter() for recursion printk: Disallow instrumenting print_nmi_enter() printk: Prepare for nested printk_nmi_enter() rcutorture: Convert ULONG_CMP_LT() to time_before() torture: Add a --kasan argument torture: Save a few lines by using config_override_param initially ...
2020-06-01Merge tag 'pstore-v5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linuxLinus Torvalds2-4/+253
Pull pstore updates from Kees Cook: "Fixes and new features for pstore. This is a pretty big set of changes (relative to past pstore pulls), but it has been in -next for a while. The biggest change here is the ability to support a block device as a pstore backend, which has been desired for a while. A lot of additional fixes and refactorings are also included, mostly in support of the new features. - refactor pstore locking for safer module unloading (Kees Cook) - remove orphaned records from pstorefs when backend unloaded (Kees Cook) - refactor dump_oops parameter into max_reason (Pavel Tatashin) - introduce pstore/zone for common code for contiguous storage (WeiXiong Liao) - introduce pstore/blk for block device backend (WeiXiong Liao) - introduce mtd backend (WeiXiong Liao)" * tag 'pstore-v5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (35 commits) mtd: Support kmsg dumper based on pstore/blk pstore/blk: Introduce "best_effort" mode pstore/blk: Support non-block storage devices pstore/blk: Provide way to query pstore configuration pstore/zone: Provide way to skip "broken" zone for MTD devices Documentation: Add details for pstore/blk pstore/zone,blk: Add ftrace frontend support pstore/zone,blk: Add console frontend support pstore/zone,blk: Add support for pmsg frontend pstore/blk: Introduce backend for block devices pstore/zone: Introduce common layer to manage storage zones ramoops: Add "max-reason" optional field to ramoops DT node pstore/ram: Introduce max_reason and convert dump_oops pstore/platform: Pass max_reason to kmesg dump printk: Introduce kmsg_dump_reason_str() printk: honor the max_reason field in kmsg_dumper printk: Collapse shutdown types into a single dump reason pstore/ftrace: Provide ftrace log merging routine pstore/ram: Refactor ftrace buffer merging pstore/ram: Refactor DT size parsing ...
2020-06-01Merge branches 'pm-devfreq', 'powercap', 'pm-docs' and 'pm-tools'Rafael J. Wysocki2-0/+918
* pm-devfreq: PM / devfreq: Use lockdep asserts instead of manual checks for locked mutex PM / devfreq: imx-bus: Fix inconsistent IS_ERR and PTR_ERR PM / devfreq: Replace strncpy with strscpy PM / devfreq: imx: Register interconnect device PM / devfreq: Add generic imx bus scaling driver PM / devfreq: tegra30: Delete an error message in tegra_devfreq_probe() PM / devfreq: tegra30: Make CPUFreq notifier to take into account boosting * powercap: powercap: RAPL: remove unused local MSR define powercap/intel_rapl: add support for ElkhartLake * pm-docs: Documentation: admin-guide: pm: Document intel-speed-select * pm-tools: cpupower: Remove unneeded semicolon
2020-06-01Merge branch 'pm-cpufreq'Rafael J. Wysocki1-13/+19
* pm-cpufreq: cpufreq: Fix up cpufreq_boost_set_sw() cpufreq: fix minor typo in struct cpufreq_driver doc comment cpufreq: qoriq: Add platform dependencies clk: qoriq: add cpufreq platform device cpufreq: qoriq: convert to a platform driver cpufreq: qcom: fix wrong compatible binding cpufreq: imx-cpufreq-dt: support i.MX7ULP cpufreq: dt: Add support for r8a7742 cpufreq: Add i.MX7ULP to cpufreq-dt-platdev blacklist cpufreq: omap: Build driver by default for ARCH_OMAP2PLUS cpufreq: intel_pstate: Use passive mode by default without HWP
2020-06-01Merge branch 'pm-cpuidle'Rafael J. Wysocki1-11/+9
* pm-cpuidle: cpuidle: Fix three reference count leaks cpuidle: Convert Qualcomm SPM driver to a generic CPUidle driver Documentation: ABI: make current_governer_ro as a candidate for removal Documentation: cpuidle: update the document cpuidle: sysfs: Remove sysfs_switch and switch attributes cpuidle: Make cpuidle governor switchable to be the default behaviour cpuidle: sysfs: Accept governor name with 15 characters cpuidle: sysfs: Fix the overlap for showing available governors cpuidle: psci: Fixup execution order when entering a domain idle state cpuidle: sysfs: Minor coding style corrections cpuidle: sysfs: Remove the unused define_one_r(o/w) macros
2020-05-31mtd: Support kmsg dumper based on pstore/blkWeiXiong Liao1-2/+7
This introduces mtdpstore, which is similar to mtdoops but more powerful. It uses pstore/blk, and aims to store panic and oops logs to a flash partition, where pstore can later read back and present as files in the mounted pstore filesystem. To make mtdpstore work, the "blkdev" of pstore/blk should be set as MTD device name or MTD device number. For more details, see Documentation/admin-guide/pstore-blk.rst This solves a number of issues: - Work duplication: both of pstore and mtdoops do the same job storing panic/oops log. They have very similar logic, registering to kmsg dumper and storing logs to several chunks one by one. - Layer violations: drivers should provides methods instead of polices. MTD should provide read/write/erase operations, and allow a higher level drivers to provide the chunk management, kmsg dump configuration, etc. - Missing features: pstore provides many additional features, including presenting the logs as files, logging dump time and count, and supporting other frontends like pmsg, console, etc. Signed-off-by: WeiXiong Liao <liaoweixiong@allwinnertech.com> Link: https://lore.kernel.org/lkml/20200511233229.27745-11-keescook@chromium.org/ Link: https://lore.kernel.org/r/1589266715-4168-1-git-send-email-liaoweixiong@allwinnertech.com Signed-off-by: Kees Cook <keescook@chromium.org>
2020-05-31pstore/blk: Support non-block storage devicesWeiXiong Liao1-4/+13
Add support for non-block devices (e.g. MTD). A non-block driver calls pstore_blk_register_device() to register iself. In addition, pstore/zone is updated to handle non-block devices, where an erase must be done before a write. Without this, there is no way to remove records stored to an MTD. Signed-off-by: WeiXiong Liao <liaoweixiong@allwinnertech.com> Link: https://lore.kernel.org/lkml/20200511233229.27745-10-keescook@chromium.org/ Co-developed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org>
2020-05-30Documentation: Add details for pstore/blkWeiXiong Liao1-0/+229
Add details on using pstore/blk, the new backend of pstore to record dumps to block devices, in Documentation/admin-guide/pstore-blk.rst Signed-off-by: WeiXiong Liao <liaoweixiong@allwinnertech.com> Link: https://lore.kernel.org/lkml/20200511233229.27745-7-keescook@chromium.org/ Signed-off-by: Kees Cook <keescook@chromium.org>
2020-05-30pstore/ram: Introduce max_reason and convert dump_oopsKees Cook1-4/+10
Now that pstore_register() can correctly pass max_reason to the kmesg dump facility, introduce a new "max_reason" module parameter and "max-reason" Device Tree field. The "dump_oops" module parameter and "dump-oops" Device Tree field are now considered deprecated, but are now automatically converted to their corresponding max_reason values when present, though the new max_reason setting has precedence. For struct ramoops_platform_data, the "dump_oops" member is entirely replaced by a new "max_reason" member, with the only existing user updated in place. Additionally remove the "reason" filter logic from ramoops_pstore_write(), as that is not specifically needed anymore, though technically this is a change in behavior for any ramoops users also setting the printk.always_kmsg_dump boot param, which will cause ramoops to behave as if max_reason was set to KMSG_DUMP_MAX. Co-developed-by: Pavel Tatashin <pasha.tatashin@soleen.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com> Link: https://lore.kernel.org/lkml/20200515184434.8470-6-keescook@chromium.org/ Signed-off-by: Kees Cook <keescook@chromium.org>
2020-05-28cgroup: add cpu.stat file to root cgroupBoris Burkov1-4/+2
Currently, the root cgroup does not have a cpu.stat file. Add one which is consistent with /proc/stat to capture global cpu statistics that might not fall under cgroup accounting. We haven't done this in the past because the data are already presented in /proc/stat and we didn't want to add overhead from collecting root cgroup stats when cgroups are configured, but no cgroups have been created. By keeping the data consistent with /proc/stat, I think we avoid the first problem, while improving the usability of cgroups stats. We avoid the second problem by computing the contents of cpu.stat from existing data collected for /proc/stat anyway. Signed-off-by: Boris Burkov <boris@bur.io> Suggested-by: Tejun Heo <tj@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2020-05-28Merge tag 'v5.7-rc7' into perf/core, to pick up fixesIngo Molnar2-7/+9
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-05-27Merge tag 'v5.7-rc7' into develLinus Walleij3-35/+28
Linux 5.7-rc7
2020-05-25docs: acpi: fix old http link and improve document formatFlavio Suligoi1-1/+1
The website: http://wiki.minnowboard.org doesn't exist anymore. The same pages are moved to: https://www.elinux.org/Minnowboard Other improvements concern the introduction of some rst semantic markup in the document. Signed-off-by: Flavio Suligoi <f.suligoi@asem.it> Link: https://lore.kernel.org/r/20200519084128.12756-2-f.suligoi@asem.it Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-05-25docs: sysctl/kernel: document unaligned controlsStephen Kitt1-0/+51
This documents ignore-unaligned-usertrap, unaligned-dump-stack, and unaligned-trap, based on arch/arc/kernel/unaligned.c, arch/ia64/kernel/unaligned.c, and arch/parisc/kernel/unaligned.c. While we're at it, integrate unaligned-memory-access.txt into the docs tree. Signed-off-by: Stephen Kitt <steve@sk2.org> Link: https://lore.kernel.org/r/20200515212443.5012-1-steve@sk2.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-05-25Documentation: admin-guide: update bug-hunting.rstRandy Dunlap1-22/+31
Update Documentation/admin-guide/bug-hunting.rst: - add a small section on "Modules linked in" and their possible flags; - delete all references to ksymoops since it is no longer applicable; - fix spello, grammar, and punctuation; - note that get_maintainers.pl only provides recent patchers if it is run inside a git tree; - add mention of scripts/decode_stacktrace.sh; Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: greg@wind.rmcc.com Link: https://lore.kernel.org/r/c629a9ef-3867-c3d1-f6c9-2c3b0e4ac68a@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-05-25docs: sysctl/kernel: document ngroups_maxStephen Kitt1-0/+9
This is a read-only export of NGROUPS_MAX. Signed-off-by: Stephen Kitt <steve@sk2.org> Link: https://lore.kernel.org/r/20200518145836.15816-1-steve@sk2.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-05-21x86/tsc: Add tsc_early_khz command line parameterKrzysztof Piecuch1-0/+6
Changing base clock frequency directly impacts TSC Hz but not CPUID.16h value. An overclocked CPU supporting CPUID.16h and with partial CPUID.15h support will set TSC KHZ according to "best guess" given by CPUID.16h relying on tsc_refine_calibration_work to give better numbers later. tsc_refine_calibration_work will refuse to do its work when the outcome is off the early TSC KHZ value by more than 1% which is certain to happen on an overclocked system. Fix this by adding a tsc_early_khz command line parameter that makes the kernel skip early TSC calibration and use the given value instead. This allows the user to provide the expected TSC frequency that is closer to reality than the one reported by the hardware, enabling tsc_refine_calibration_work to do meaningful error checking. [ tglx: Made the variable __initdata as it's only used on init and removed the error checking in the argument parser because kstrto*() only stores to the variable if the string is valid ] Signed-off-by: Krzysztof Piecuch <piecuch@protonmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/O2CpIOrqLZHgNRkfjRpz_LGqnc1ix_seNIiOCvHY4RHoulOVRo6kMXKuLOfBVTi0SMMevg6Go1uZ_cL9fLYtYdTRNH78ChaFaZyG3VAyYz8=@protonmail.com
2020-05-20dm zoned: metadata version 2Hannes Reinecke1-7/+27
Implement handling for metadata version 2. The new metadata adds a label and UUID for the device mapper device, and additional UUID for the underlying block devices. It also allows for an additional regular drive to be used for emulating random access zones. The emulated zones will be placed logically in front of the zones from the zoned block device, causing the superblocks and metadata to be stored on that device. The first zone of the original zoned device will be used to hold another, tertiary copy of the metadata; this copy carries a generation number of 0 and is never updated; it's just used for identification. Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Bob Liu <bob.liu@oracle.com> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-05-20powerpc/64s/hash: Add stress_slb kernel boot option to increase SLB faultsNicholas Piggin1-0/+5
This option increases the number of SLB misses by limiting the number of kernel SLB entries, and increased flushing of cached lookaside information. This helps stress test difficult to hit paths in the kernel. Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Relocate the code into arch/powerpc/mm, s/torture/stress/] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200511125825.3081305-1-mpe@ellerman.id.au
2020-05-19Documentation: admin-guide: pm: Document intel-speed-selectSrinivas Pandruvada2-0/+918
Added documentation to configure servers to use Intel(R) Speed Select Technology using intel-speed-select tool. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Acked-by: Andriy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-05-19Documentation: cpuidle: update the documentHanjun Guo1-11/+9
Update the document after the remove of cpuidle_sysfs_switch. Signed-off-by: Hanjun Guo <guohanjun@huawei.com> Reviewed-by: Doug Smythies <dsmythies@telus.net> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-05-19Merge tag 'noinstr-lds-2020-05-19' into core/rcuThomas Gleixner2-7/+9
Get the noinstr section and annotation markers to base the RCU parts on.
2020-05-18Revert "docs: sysctl/kernel: document ngroups_max"Jonathan Corbet1-9/+0
This reverts commit 2f4c33063ad713e3a5b63002cf8362846e78bd71. The changes here were fine, but there's a non-documentation change to sysctl.c that makes messes elsewhere; those changes should have been done independently. Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-05-18docs: gpio: Add GPIO Aggregator documentationGeert Uytterhoeven2-0/+112
Document the GPIO Aggregator, and the two typical use-cases. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Tested-by: Eugeniu Rosca <erosca@de.adit-jv.com> Reviewed-by: Ulrich Hecht <uli+renesas@fpond.eu> Reviewed-by: Eugeniu Rosca <erosca@de.adit-jv.com> Link: https://lore.kernel.org/r/20200511145257.22970-6-geert+renesas@glider.be Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2020-05-16netns: enable to inherit devconf from current netnsNicolas Dichtel1-1/+3
The goal is to be able to inherit the initial devconf parameters from the current netns, ie the netns where this new netns has been created. This is useful in a containers environment where /proc/sys is read only. For example, if a pod is created with specifics devconf parameters and has the capability to create netns, the user expects to get the same parameters than his 'init_net', which is not the real init_net in this case. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-15docs: add IRQ documentation at the core-api bookMauro Carvalho Chehab2-2/+2
There are 4 IRQ documentation files under Documentation/*.txt. Move them into a new directory (core-api/irq) and add a new index file for it. While here, use a title markup for the Debugging section of the irq-domain.rst file. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/2da7485c3718e1442e6b4c2dd66857b776e8899b.1588345503.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-05-15docs: debugging-via-ohci1394.txt: add it to the core-api bookMauro Carvalho Chehab1-1/+1
There is an special chapter inside the core-api book about some debug infrastructure like tracepoints and debug objects. It sounded to me that this is the best place to add a chapter explaining how to use a FireWire controller to do remote kernel debugging, as explained on this document. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/9b489d36d08ad89d3ad5aefef1f52a0715b29716.1588345503.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-05-15doc: Fix some errors in ras.rstWaiman Long1-5/+5
Make some miscellaneous fixes to the first paragraph of "ECC memory": - Change the incorrect "74 bits" to "72 bits". - Change "mentioned on" to "mentioned in". - Remove the extra "extra". - Rephrase some sentences as suggested by Matthew Wilcox. Signed-off-by: Waiman Long <longman@redhat.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Link: https://lore.kernel.org/r/20200506162217.16633-1-longman@redhat.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-05-15Documentation: update numastat explanationVlastimil Babka1-3/+28
During recent patch discussion [1] it became apparent that the "other_node" definition in the numastat documentation has always been different from actual implementation. It was also noted that the stats can be innacurate on systems with memoryless nodes. This patch corrects the other_node definition (with minor tweaks to two more definitions), adds a note about memoryless nodes and also two introductory paragraphs to the numastat documentation. [1] https://lore.kernel.org/linux-mm/20200504070304.127361-1-sandipan@linux.ibm.com/T/#u Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Sandipan Das <sandipan@linux.ibm.com> Acked-by: Michal Hocko <mhocko@suse.com> Link: https://lore.kernel.org/r/20200507120217.12313-1-vbabka@suse.cz Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-05-15docs: sysctl/kernel: document ngroups_maxStephen Kitt1-0/+9
This is a read-only export of NGROUPS_MAX, so this patch also changes the declarations in kernel/sysctl.c to const. Signed-off-by: Stephen Kitt <steve@sk2.org> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20200515160222.7994-1-steve@sk2.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-05-15dm zoned: add 'message' callbackHannes Reinecke1-0/+12
Add callback for 'dmsetup message' to allow the reclaim process to be triggered manually. Eg. dmsetup message /dev/dm-X 0 message will start the reclaim process even if the default threshold of 50 percent of free random zones is not reached. Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Bob Liu <bob.liu@oracle.com> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-05-15dm zoned: add 'status' callbackHannes Reinecke1-0/+16
Add callback to supply information for 'dmsetup status' and 'dmsetup table'. The output for 'dmsetup status' is 0 <size> zoned <nr_zones> zones <nr_unmap_rnd>/<nr_rnd> random <nr_unmap_seq>/<nr_seq> sequential where <nr_unmap_rnd> is the number of unmapped (ie free) random zones, <nr_rnd> the total number of random zones, <nr_unmap_seq> the number of unmapped sequential zones, and <nr_seq> the total number of sequential zones. Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Bob Liu <bob.liu@oracle.com> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-05-15dm: add emulated block size targetHeinz Mauelshagen1-0/+51
This new target is similar to the linear target except that it emulates a smaller logical block size on a device with a larger logical block size. Its main purpose is to emulate 512 byte sectors on 4K native disks (i.e. 512e). See Documentation/admin-guide/device-mapper/dm-ebs.rst for details. Reviewed-by: Damien Le Moal <DamienLeMoal@wdc.com> Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> [Kconfig fixes] Signed-off-by: Zheng Bin <zhengbin13@huawei.com> [static fixes] Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-05-15tty/sysrq: constify the sysrq APIEmil Velikov1-5/+5
The user is not supposed to thinker with the underlying sysrq_key_op. Make that explicit by adding a handful of const notations. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: linux-kernel@vger.kernel.org Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com> Link: https://lore.kernel.org/r/20200513214351.2138580-2-emil.l.velikov@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-13streamline_config.pl: add LMC_KEEP to preserve some kconfigsChangbin Du1-2/+9
Sometimes it is useful to preserve batches of configs when making localmodconfig. For example, I usually don't want any usb and fs modules to be disabled. Now we can do it by: $ make LMC_KEEP="drivers/usb:fs" localmodconfig Signed-off-by: Changbin Du <changbin.du@gmail.com> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-11Documentation/vmcoreinfo: Add documentation for 'KERNELPACMASK'Amit Daniel Kachhap1-0/+6
Add documentation for KERNELPACMASK variable being added to the vmcoreinfo. It indicates the PAC bits mask information of signed kernel pointers if Armv8.3-A Pointer Authentication feature is present. Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: Baoquan He <bhe@redhat.com> Link: https://lore.kernel.org/r/1589202116-18265-2-git-send-email-amit.kachhap@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2020-05-07Merge branches 'fixes.2020.04.27a', 'kfree_rcu.2020.04.27a', 'rcu-tasks.2020.04.27a', 'stall.2020.04.27a' and 'torture.2020.05.07a' into HEADPaul E. McKenney1-0/+19
fixes.2020.04.27a: Miscellaneous fixes. kfree_rcu.2020.04.27a: Changes related to kfree_rcu(). rcu-tasks.2020.04.27a: Addition of new RCU-tasks flavors. stall.2020.04.27a: RCU CPU stall-warning updates. torture.2020.05.07a: Torture-test updates.
2020-05-07rcu: Allow rcutorture to starve grace-period kthreadPaul E. McKenney1-0/+7
This commit provides an rcutorture.stall_gp_kthread module parameter to allow rcutorture to starve the grace-period kthread. This allows testing the code that detects such starvation. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-05-07rcutorture: Add flag to produce non-busy-wait task stallsPaul E. McKenney1-0/+5
This commit aids testing of RCU task stall warning messages by adding an rcutorture.stall_cpu_block module parameter that results in the induced stall sleeping within the RCU read-side critical section. Spinning with interrupts disabled is still available via the rcutorture.stall_cpu_irqsoff module parameter, and specifying neither of these two module parameters will spin with preemption disabled. Note that sleeping (as opposed to preemption) results in additional complaints from RCU at context-switch time, so yet more testing. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-05-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller2-7/+9
Conflicts were all overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-06media: ipu3.rst: fix a build warningMauro Carvalho Chehab1-1/+2
Sphinx 2.4.4 produces this warning: Documentation/admin-guide/media/ipu3.rst:235: WARNING: Title underline too short. Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-05-05docs: sysctl/kernel: document firmware_configStephen Kitt1-0/+13
Based on the firmware fallback mechanisms documentation and the implementation in drivers/base/firmware_loader/fallback.c. Signed-off-by: Stephen Kitt <steve@sk2.org> Link: https://lore.kernel.org/r/20200429205757.8677-2-steve@sk2.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-05-05docs: sysctl/kernel: document ftrace entriesStephen Kitt1-0/+48
Based on the ftrace documentation, the tp_printk boot parameter documentation, and the implementation in kernel/trace/trace.c. Signed-off-by: Stephen Kitt <steve@sk2.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20200429205757.8677-1-steve@sk2.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-05-05media: admin-guide: split cardlist.rst fileMauro Carvalho Chehab7-706/+723
After adding all cardlists, this file became too big. Split it on smaller files, in order to make easier to maintain. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-05-05media: admin-guide: make clear about PCI subsystem IDsMauro Carvalho Chehab8-18/+25
On several parts of the document, it mentions "PCI ID", when it is actually referring to the subsystem's part of the PCI ID. Change the language to let it be clear. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>