summaryrefslogtreecommitdiffstats
path: root/Documentation/ABI/testing/sysfs-devices-system-cpu
Commit message (Collapse)AuthorAgeFilesLines
* Merge branch 'x86-mds-for-linus' of ↵Linus Torvalds2019-05-141-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 MDS mitigations from Thomas Gleixner: "Microarchitectural Data Sampling (MDS) is a hardware vulnerability which allows unprivileged speculative access to data which is available in various CPU internal buffers. This new set of misfeatures has the following CVEs assigned: CVE-2018-12126 MSBDS Microarchitectural Store Buffer Data Sampling CVE-2018-12130 MFBDS Microarchitectural Fill Buffer Data Sampling CVE-2018-12127 MLPDS Microarchitectural Load Port Data Sampling CVE-2019-11091 MDSUM Microarchitectural Data Sampling Uncacheable Memory MDS attacks target microarchitectural buffers which speculatively forward data under certain conditions. Disclosure gadgets can expose this data via cache side channels. Contrary to other speculation based vulnerabilities the MDS vulnerability does not allow the attacker to control the memory target address. As a consequence the attacks are purely sampling based, but as demonstrated with the TLBleed attack samples can be postprocessed successfully. The mitigation is to flush the microarchitectural buffers on return to user space and before entering a VM. It's bolted on the VERW instruction and requires a microcode update. As some of the attacks exploit data structures shared between hyperthreads, full protection requires to disable hyperthreading. The kernel does not do that by default to avoid breaking unattended updates. The mitigation set comes with documentation for administrators and a deeper technical view" * 'x86-mds-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) x86/speculation/mds: Fix documentation typo Documentation: Correct the possible MDS sysfs values x86/mds: Add MDSUM variant to the MDS documentation x86/speculation/mds: Add 'mitigations=' support for MDS x86/speculation/mds: Print SMT vulnerable on MSBDS with mitigations off x86/speculation/mds: Fix comment x86/speculation/mds: Add SMT warning message x86/speculation: Move arch_smt_update() call to after mitigation decisions x86/speculation/mds: Add mds=full,nosmt cmdline option Documentation: Add MDS vulnerability documentation Documentation: Move L1TF to separate directory x86/speculation/mds: Add mitigation mode VMWERV x86/speculation/mds: Add sysfs reporting for MDS x86/speculation/mds: Add mitigation control for MDS x86/speculation/mds: Conditionally clear CPU buffers on idle entry x86/kvm/vmx: Add MDS protection when L1D Flush is not active x86/speculation/mds: Clear CPU buffers on exit to user x86/speculation/mds: Add mds_clear_cpu_buffers() x86/kvm: Expose X86_FEATURE_MD_CLEAR to guests x86/speculation/mds: Add BUG_MSBDS_ONLY ...
| * Documentation: Add MDS vulnerability documentationThomas Gleixner2019-03-061-2/+1
| | | | | | | | | | | | | | Add the initial MDS vulnerability documentation. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jon Masters <jcm@redhat.com>
| * Documentation: Move L1TF to separate directoryThomas Gleixner2019-03-061-1/+1
| | | | | | | | | | | | | | | | | | | | Move L!TF to a separate directory so the MDS stuff can be added at the side. Otherwise the all hardware vulnerabilites have their own top level entry. Should have done that right away. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Jon Masters <jcm@redhat.com>
| * x86/speculation/mds: Add sysfs reporting for MDSThomas Gleixner2019-03-061-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | Add the sysfs reporting file for MDS. It exposes the vulnerability and mitigation state similar to the existing files for the other speculative hardware vulnerabilities. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jon Masters <jcm@redhat.com> Tested-by: Jon Masters <jcm@redhat.com>
* | Merge tag 'pm-5.2-rc1' of ↵Linus Torvalds2019-05-061-0/+18
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These fix the (Intel-specific) Performance and Energy Bias Hint (EPB) handling and expose it to user space via sysfs, fix and clean up several cpufreq drivers, add support for two new chips to the qoriq cpufreq driver, fix, simplify and clean up the cpufreq core and the schedutil governor, add support for "CPU" domains to the generic power domains (genpd) framework and provide low-level PSCI firmware support for that feature, fix the exynos cpuidle driver and fix a couple of issues in the devfreq subsystem and clean it up. Specifics: - Fix the handling of Performance and Energy Bias Hint (EPB) on Intel processors and expose it to user space via sysfs to avoid having to access it through the generic MSR I/F (Rafael Wysocki). - Improve the handling of global turbo changes made by the platform firmware in the intel_pstate driver (Rafael Wysocki). - Convert some slow-path static_cpu_has() callers to boot_cpu_has() in cpufreq (Borislav Petkov). - Fix the frequency calculation loop in the armada-37xx cpufreq driver (Gregory CLEMENT). - Fix possible object reference leaks in multuple cpufreq drivers (Wen Yang). - Fix kerneldoc comment in the centrino cpufreq driver (dongjian). - Clean up the ACPI and maple cpufreq drivers (Viresh Kumar, Mohan Kumar). - Add support for lx2160a and ls1028a to the qoriq cpufreq driver (Vabhav Sharma, Yuantian Tang). - Fix kobject memory leak in the cpufreq core (Viresh Kumar). - Simplify the IOwait boosting in the schedutil cpufreq governor and rework the TSC cpufreq notifier on x86 (Rafael Wysocki). - Clean up the cpufreq core and statistics code (Yue Hu, Kyle Lin). - Improve the cpufreq documentation, add SPDX license tags to some PM documentation files and unify copyright notices in them (Rafael Wysocki). - Add support for "CPU" domains to the generic power domains (genpd) framework and provide low-level PSCI firmware support for that feature (Ulf Hansson). - Rearrange the PSCI firmware support code and add support for SYSTEM_RESET2 to it (Ulf Hansson, Sudeep Holla). - Improve genpd support for devices in multiple power domains (Ulf Hansson). - Unify target residency for the AFTR and coupled AFTR states in the exynos cpuidle driver (Marek Szyprowski). - Introduce new helper routine in the operating performance points (OPP) framework (Andrew-sh.Cheng). - Add support for passing on-die termination (ODT) and auto power down parameters from the kernel to Trusted Firmware-A (TF-A) to the rk3399_dmc devfreq driver (Enric Balletbo i Serra). - Add tracing to devfreq (Lukasz Luba). - Make the exynos-bus devfreq driver suspend all devices on system shutdown (Marek Szyprowski). - Fix a few minor issues in the devfreq subsystem and clean it up somewhat (Enric Balletbo i Serra, MyungJoo Ham, Rob Herring, Saravana Kannan, Yangtao Li). - Improve system wakeup diagnostics (Stephen Boyd). - Rework filesystem sync messages emitted during system suspend and hibernation (Harry Pan)" * tag 'pm-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (72 commits) cpufreq: Fix kobject memleak cpufreq: armada-37xx: fix frequency calculation for opp cpufreq: centrino: Fix centrino_setpolicy() kerneldoc comment cpufreq: qoriq: add support for lx2160a x86: tsc: Rework time_cpufreq_notifier() PM / Domains: Allow to attach a CPU via genpd_dev_pm_attach_by_id|name() PM / Domains: Search for the CPU device outside the genpd lock PM / Domains: Drop unused in-parameter to some genpd functions PM / Domains: Use the base device for driver_deferred_probe_check_state() cpufreq: qoriq: Add ls1028a chip support PM / Domains: Enable genpd_dev_pm_attach_by_id|name() for single PM domain PM / Domains: Allow OF lookup for multi PM domain case from ->attach_dev() PM / Domains: Don't kfree() the virtual device in the error path cpufreq: Move ->get callback check outside of __cpufreq_get() PM / Domains: remove unnecessary unlikely() cpufreq: Remove needless bios_limit check in show_bios_limit() drivers/cpufreq/acpi-cpufreq.c: This fixes the following checkpatch warning firmware/psci: add support for SYSTEM_RESET2 PM / devfreq: add tracing for scheduling work trace: events: add devfreq trace event file ...
| * | PM / arch: x86: MSR_IA32_ENERGY_PERF_BIAS sysfs interfaceRafael J. Wysocki2019-04-071-0/+18
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Performance and Energy Bias Hint (EPB) is expected to be set by user space through the generic MSR interface, but that interface is not particularly nice and there are security concerns regarding it, so it is not always available. For this reason, add a sysfs interface for reading and updating the EPB, in the form of a new attribute, energy_perf_bias, located under /sys/devices/system/cpu/cpu#/power/ for online CPUs that support the EPB feature. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Acked-by: Borislav Petkov <bp@suse.de>
* / cpu/hotplug: Create SMT sysfs interface for all archesJosh Poimboeuf2019-04-021-4/+6
|/ | | | | | | | | | | | | | | | | | | Make the /sys/devices/system/cpu/smt/* files available on all arches, so user space has a consistent way to detect whether SMT is enabled. The 'control' file now shows 'notimplemented' for architectures which don't yet have CONFIG_HOTPLUG_SMT. [ tglx: Make notimplemented a real state ] Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Waiman Long <longman@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Jiri Kosina <jikos@kernel.org> Link: https://lkml.kernel.org/r/469c2b98055f2c41e75748e06447d592a64080c9.1553635520.git.jpoimboe@redhat.com
* cpuidle: Add 'above' and 'below' idle state metricsRafael J. Wysocki2018-12-121-0/+7
| | | | | | | | | | | | Add two new metrics for CPU idle states, "above" and "below", to count the number of times the given state had been asked for (or entered from the kernel's perspective), but the observed idle duration turned out to be too short or too long for it (respectively). These metrics help to estimate the quality of the CPU idle governor in use. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* x86/bugs, kvm: Introduce boot-time control of L1TF mitigationsJiri Kosina2018-07-131-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce the 'l1tf=' kernel command line option to allow for boot-time switching of mitigation that is used on processors affected by L1TF. The possible values are: full Provides all available mitigations for the L1TF vulnerability. Disables SMT and enables all mitigations in the hypervisors. SMT control via /sys/devices/system/cpu/smt/control is still possible after boot. Hypervisors will issue a warning when the first VM is started in a potentially insecure configuration, i.e. SMT enabled or L1D flush disabled. full,force Same as 'full', but disables SMT control. Implies the 'nosmt=force' command line option. sysfs control of SMT and the hypervisor flush control is disabled. flush Leaves SMT enabled and enables the conditional hypervisor mitigation. Hypervisors will issue a warning when the first VM is started in a potentially insecure configuration, i.e. SMT enabled or L1D flush disabled. flush,nosmt Disables SMT and enables the conditional hypervisor mitigation. SMT control via /sys/devices/system/cpu/smt/control is still possible after boot. If SMT is reenabled or flushing disabled at runtime hypervisors will issue a warning. flush,nowarn Same as 'flush', but hypervisors will not warn when a VM is started in a potentially insecure configuration. off Disables hypervisor mitigations and doesn't emit any warnings. Default is 'flush'. Let KVM adhere to these semantics, which means: - 'lt1f=full,force' : Performe L1D flushes. No runtime control possible. - 'l1tf=full' - 'l1tf-flush' - 'l1tf=flush,nosmt' : Perform L1D flushes and warn on VM start if SMT has been runtime enabled or L1D flushing has been run-time enabled - 'l1tf=flush,nowarn' : Perform L1D flushes and no warnings are emitted. - 'l1tf=off' : L1D flushes are not performed and no warnings are emitted. KVM can always override the L1D flushing behavior using its 'vmentry_l1d_flush' module parameter except when lt1f=full,force is set. This makes KVM's private 'nosmt' option redundant, and as it is a bit non-systematic anyway (this is something to control globally, not on hypervisor level), remove that option. Add the missing Documentation entry for the l1tf vulnerability sysfs file while at it. Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Jiri Kosina <jkosina@suse.cz> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lkml.kernel.org/r/20180713142323.202758176@linutronix.de
* cpu/hotplug: Provide knobs to control SMTThomas Gleixner2018-06-211-0/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Provide a command line and a sysfs knob to control SMT. The command line options are: 'nosmt': Enumerate secondary threads, but do not online them 'nosmt=force': Ignore secondary threads completely during enumeration via MP table and ACPI/MADT. The sysfs control file has the following states (read/write): 'on': SMT is enabled. Secondary threads can be freely onlined 'off': SMT is disabled. Secondary threads, even if enumerated cannot be onlined 'forceoff': SMT is permanentely disabled. Writes to the control file are rejected. 'notsupported': SMT is not supported by the CPU The command line option 'nosmt' sets the sysfs control to 'off'. This can be changed to 'on' to reenable SMT during runtime. The command line option 'nosmt=force' sets the sysfs control to 'forceoff'. This cannot be changed during runtime. When SMT is 'on' and the control file is changed to 'off' then all online secondary threads are offlined and attempts to online a secondary thread later on are rejected. When SMT is 'off' and the control file is changed to 'on' then secondary threads can be onlined again. The 'off' -> 'on' transition does not automatically online the secondary threads. When the control file is set to 'forceoff', the behaviour is the same as setting it to 'off', but the operation is irreversible and later writes to the control file are rejected. When the control status is 'notsupported' then writes to the control file are rejected. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Ingo Molnar <mingo@kernel.org>
* ABI: sysfs-devices-system-cpu: remove a broken referenceMauro Carvalho Chehab2018-06-151-3/+0
| | | | | | | | | | | This file doesn't exist anymore: Documentation/cpu-freq/user-guide.txt As the ABI already points to Documentation/cpu-freq, just remove the broken link and the associated text. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Acked-by: Jonathan Corbet <corbet@lwn.net>
* x86/bugs: Expose /sys/../spec_store_bypassKonrad Rzeszutek Wilk2018-05-031-0/+1
| | | | | | | | | | | | | | | Add the sysfs file for the new vulerability. It does not do much except show the words 'Vulnerable' for recent x86 cores. Intel cores prior to family 6 are known not to be vulnerable, and so are some Atoms and some Xeon Phi. It assumes that older Cyrix, Centaur, etc. cores are immune. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Ingo Molnar <mingo@kernel.org>
* PM: cpuidle/suspend: Add s2idle usage and time state attributesRafael J. Wysocki2018-03-291-0/+25
| | | | | | | | | | | | | | | Add a new attribute group called "s2idle" under the sysfs directory of each cpuidle state that supports the ->enter_s2idle callback and put two new attributes, "usage" and "time", into that group to represent the number of times the given state was requested for suspend-to-idle and the total time spent in suspend-to-idle after requesting that state, respectively. That will allow diagnostic information related to suspend-to-idle to be collected without enabling advanced debug features and analyzing dmesg output. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* Documentation/ABI: update cpuidle sysfs documentationAishwarya Pant2018-02-121-2/+75
| | | | | | | | | Update cpuidle documentation using git logs and existing documentation in Documentation/cpuidle/sysfs.txt. This might be useful for scripting and tracking changes in the ABI. Signed-off-by: Aishwarya Pant <aishpant@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds2018-01-141-0/+16
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 pti updates from Thomas Gleixner: "This contains: - a PTI bugfix to avoid setting reserved CR3 bits when PCID is disabled. This seems to cause issues on a virtual machine at least and is incorrect according to the AMD manual. - a PTI bugfix which disables the perf BTS facility if PTI is enabled. The BTS AUX buffer is not globally visible and causes the CPU to fault when the mapping disappears on switching CR3 to user space. A full fix which restores BTS on PTI is non trivial and will be worked on. - PTI bugfixes for EFI and trusted boot which make sure that the user space visible page table entries have the NX bit cleared - removal of dead code in the PTI pagetable setup functions - add PTI documentation - add a selftest for vsyscall to verify that the kernel actually implements what it advertises. - a sysfs interface to expose vulnerability and mitigation information so there is a coherent way for users to retrieve the status. - the initial spectre_v2 mitigations, aka retpoline: + The necessary ASM thunk and compiler support + The ASM variants of retpoline and the conversion of affected ASM code + Make LFENCE serializing on AMD so it can be used as speculation trap + The RSB fill after vmexit - initial objtool support for retpoline As I said in the status mail this is the most of the set of patches which should go into 4.15 except two straight forward patches still on hold: - the retpoline add on of LFENCE which waits for ACKs - the RSB fill after context switch Both should be ready to go early next week and with that we'll have covered the major holes of spectre_v2 and go back to normality" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (28 commits) x86,perf: Disable intel_bts when PTI security/Kconfig: Correct the Documentation reference for PTI x86/pti: Fix !PCID and sanitize defines selftests/x86: Add test_vsyscall x86/retpoline: Fill return stack buffer on vmexit x86/retpoline/irq32: Convert assembler indirect jumps x86/retpoline/checksum32: Convert assembler indirect jumps x86/retpoline/xen: Convert Xen hypercall indirect jumps x86/retpoline/hyperv: Convert assembler indirect jumps x86/retpoline/ftrace: Convert ftrace assembler indirect jumps x86/retpoline/entry: Convert entry assembler indirect jumps x86/retpoline/crypto: Convert crypto assembler indirect jumps x86/spectre: Add boot time option to select Spectre v2 mitigation x86/retpoline: Add initial retpoline support objtool: Allow alternatives to be ignored objtool: Detect jumps to retpoline thunks x86/pti: Make unpoison of pgd for trusted boot work for real x86/alternatives: Fix optimize_nops() checking sysfs/cpu: Fix typos in vulnerability documentation x86/cpu/AMD: Use LFENCE_RDTSC in preference to MFENCE_RDTSC ...
| * sysfs/cpu: Fix typos in vulnerability documentationDavid Woodhouse2018-01-091-2/+2
| | | | | | | | | | | | | | Fixes: 87590ce6e ("sysfs/cpu: Add vulnerability folder") Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * sysfs/cpu: Add vulnerability folderThomas Gleixner2018-01-081-0/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As the meltdown/spectre problem affects several CPU architectures, it makes sense to have common way to express whether a system is affected by a particular vulnerability or not. If affected the way to express the mitigation should be common as well. Create /sys/devices/system/cpu/vulnerabilities folder and files for meltdown, spectre_v1 and spectre_v2. Allow architectures to override the show function. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linuxfoundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: David Woodhouse <dwmw@amazon.co.uk> Link: https://lkml.kernel.org/r/20180107214913.096657732@linutronix.de
* | Documentation: fix admin-guide doc refsTom Saeger2017-10-121-2/+4
|/ | | | | | | | Make admin-guide document refs valid. Signed-off-by: Tom Saeger <tom.saeger@oracle.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* Documentation/ABI: add information about cpu_capacityJuri Lelli2017-04-081-0/+7
| | | | | | | | | | | /sys/devices/system/cpu/cpu#/cpu_capacity describe information about CPUs heterogeneity (ref. to Documentation/devicetree/bindings/arm/ cpu-capacity.txt). Add such description. Signed-off-by: Juri Lelli <juri.lelli@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Documentation, ABI: Document the new sysfs files for cpu cache idsTony Luck2016-10-261-0/+16
| | | | | | | | | | | | | | | | | | | | | | Add an ABI document entry for /sys/devices/system/cpu/cpu*/cache/index*/id. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com> Cc: "David Carrillo-Cisneros" <davidcc@google.com> Cc: "Sai Prakhya" <sai.praneeth.prakhya@intel.com> Cc: "Peter Zijlstra" <peterz@infradead.org> Cc: "Stephane Eranian" <eranian@google.com> Cc: "Dave Hansen" <dave.hansen@intel.com> Cc: "Shaohua Li" <shli@fb.com> Cc: "Nilay Vaish" <nilayvaish@gmail.com> Cc: "Vikas Shivappa" <vikas.shivappa@linux.intel.com> Cc: "Ingo Molnar" <mingo@elte.hu> Cc: "Borislav Petkov" <bp@suse.de> Cc: "H. Peter Anvin" <h.peter.anvin@intel.com> Link: http://lkml.kernel.org/r/1477142405-32078-2-git-send-email-fenghua.yu@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* arm64: cpuinfo: Expose MIDR_EL1 and REVIDR_EL1 to sysfsSteve Capper2016-07-121-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | It can be useful for JIT software to be aware of MIDR_EL1 and REVIDR_EL1 to ascertain the presence of any core errata that could affect code generation. This patch exposes these registers through sysfs: /sys/devices/system/cpu/cpu$ID/regs/identification/midr_el1 /sys/devices/system/cpu/cpu$ID/regs/identification/revidr_el1 where $ID is the cpu number. For big.LITTLE systems, one can have a mixture of cores (e.g. Cortex A53 and Cortex A57), thus all CPUs need to be enumerated. If the kernel does not have valid information to populate these entries with, an empty string is returned to userspace. Cc: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Steve Capper <steve.capper@linaro.org> [suzuki.poulose@arm.com: ABI documentation updates, hotplug notifiers, kobject changes] Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* cpufreq: powernv: Add sysfs attributes to show throttle statsShilpasri G Bhat2016-03-221-0/+69
| | | | | | | | | | | | | | | | | | | | | | Create sysfs attributes to export throttle information in /sys/devices/system/cpu/cpuX/cpufreq/throttle_stats directory. The newly added sysfs files are as follows: 1)/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/turbo_stat 2)/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/sub-turbo_stat 3)/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/unthrottle 4)/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/powercap 5)/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/overtemp 6)/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/supply_fault 7)/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/overcurrent 8)/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/occ_reset Detailed explanation of each attribute is added to Documentation/ABI/testing/sysfs-devices-system-cpu Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* Merge 4.1-rc7 into driver-core-nextGreg Kroah-Hartman2015-06-081-1/+1
|\ | | | | | | | | | | | | We want the fixes in this branch as well for testing and merge resolution. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * x86/Documentation: Update the contact email for L3 cache index disable ↵Aravind Gopalakrishnan2015-05-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | functionality The mailing list discuss@x86-64.org is now defunct. Use the lkml in its place. Signed-off-by: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Greg KH <greg@kroah.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-api@vger.kernel.org Cc: sboyd@codeaurora.org Cc: sudeep.holla@arm.com Link: http://lkml.kernel.org/r/1431125098-9470-1-git-send-email-Aravind.Gopalakrishnan@amd.com Link: http://lkml.kernel.org/r/1431936437-25286-2-git-send-email-bp@alien8.de [ Changed the contact email to lkml. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | drivers/base: cacheinfo: fix annoying typo when DT nodes are absentWill Deacon2015-05-241-1/+1
|/ | | | | | | | | | | | s/hierarcy/hierarchy/ Maybe the typo will annoy people enough so that they add the missing nodes to their device-tree files, but I still think this is better off fixed. Signed-off-by: Will Deacon <will.deacon@arm.com> Acked-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* drivers: base: support cpu cache information interface to userspace via sysfsSudeep Holla2014-11-071-0/+47
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds initial support for providing processor cache information to userspace through sysfs interface. This is based on already existing implementations(x86, ia64, s390 and powerpc) and hence the interface is intended to be fully compatible. The main purpose of this generic support is to avoid further code duplication to support new architectures and also to unify all the existing different implementations. This implementation maintains the hierarchy of cache objects which reflects the system's cache topology. Cache devices are instantiated as needed as CPUs come online. The cache information is replicated per-cpu even if they are shared. A per-cpu array of cache information maintained is used mainly for sysfs-related book keeping. It also implements the shared_cpu_map attribute, which is essential for enabling both kernel and user-space to discover the system's overall cache topology. This patch also add the missing ABI documentation for the cacheinfo sysfs interface already, which is well defined and widely used. Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Tested-by: Stephen Boyd <sboyd@codeaurora.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: linux-api@vger.kernel.org Cc: linux390@de.ibm.com Cc: linux-arm-kernel@lists.infradead.org Cc: linux-ia64@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-s390@vger.kernel.org Cc: x86@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* cpufreq: Make linux-pm@vger.kernel.org official mailing listViresh Kumar2014-05-011-2/+2
| | | | | | | | | | | | | | | | There has been confusion all the time about which mailing list to follow for cpufreq activities, linux-pm@vger.kernel.org or cpufreq@vger.kernel.org. Since patches sent to cpufreq@vger.kernel.org don't go to Patchwork which is a maintenance workflow problem, make linux-pm@vger.kernel.org the official mailing list for cpufreq stuff and remove all references of cpufreq@vger.kernel.org from kernel source. Later, we can request that the list be dropped entirely. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> [rjw: Changelog] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* Documentation: add ABI entry for intel_pstateRamkumar Ramachandra2014-01-061-0/+24
| | | | | | | | | | | | Add a Documentation/ABI entry for /sys/devices/system/cpu/intel_pstate/max_perf_pct, /sys/devices/system/cpu/intel_pstate/min_perf_pct, and /sys/devices/system/cpu/intel_pstate/no_turbo. Cc: Dirk Brandewie <dirk.brandewie@gmail.com> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* acpi-cpufreq: Add new sysfs attribute freqdomain_cpusLan Tianyu2013-06-271-0/+15
| | | | | | | | | | | | | | | | | | | | | Commits fcf8058 (cpufreq: Simplify cpufreq_add_dev()) and aa77a52 (cpufreq: acpi-cpufreq: Don't set policy->related_cpus from .init()) changed the contents of the "related_cpus" sysfs attribute on systems where acpi-cpufreq is used and user space can't get the list of CPUs which are in the same hardware coordination CPU domain (provided by the ACPI AML method _PSD) via "related_cpus" any more. To make up for that loss add a new sysfs attribute "freqdomian_cpus" for the acpi-cpufreq driver which exposes the list of CPUs in the same domain regardless of whether it is coordinated by hardware or software. [rjw: Changelog, documentation] References: https://bugzilla.kernel.org/show_bug.cgi?id=58761 Reported-by: Jean-Philippe Halimi <jean-philippe.halimi@exascale-computing.eu> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* Documentation: Add ABI entry for crash_notes and crash_notes_sizeZhang Yanfei2013-03-291-0/+12
| | | | | | | | | | | Add an Documentation/ABI entry for /sys/devices/system/cpu/cpu0/crash_notes and /sys/devices/system/cpu/cpu0/crash_notes_size. Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Acked-by: Simon Horman <horms@verge.net.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Revert "Documentation: ABI: /sys/devices/system/cpu/cpu#/node"Kusanagi Kouichi2013-01-031-14/+0
| | | | | | | | | | | This reverts commit cba5dd7fa535b7684cba68e17ac8be5b0083dc3d. Commit cba5dd7fa535b7684cba68e17ac8be5b0083dc3d duplicates /sys/devices/system/cpu/cpu#/node entry. Commit 657348a056eea4a27be20cf8e22c98a252597447 has already added it. Signed-off-by: Kusanagi Kouichi <slash@ac.auone-net.jp> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* acpi-cpufreq: Add support for disabling dynamic overclockingAndre Przywara2012-09-091-0/+11
| | | | | | | | | | | | | | | | | | | | | | | One feature present in powernow-k8 that isn't present in acpi-cpufreq is support for enabling or disabling AMD's core performance boost technology. This patch adds support to acpi-cpufreq, but also includes support for Intel's dynamic acceleration. The original boost disabling sysfs file was per CPU, but acted globally. Also the naming (cpb) was at least not intuitive. So lets introduce a single file simply called "boost", which sits once in /sys/devices/system/cpu/cpufreq. This should be the only way of using this feature, so add documentation about the rationale and the usage. A following patch will re-introduce the cpb knob for compatibility reasons on AMD CPUs. Per-CPU boost switching is possible, but not trivial and is thus postponed to a later patch series. Signed-off-by: Andre Przywara <andre.przywara@amd.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* sched: Remove stale power aware scheduling remnants and dysfunctional knobsPeter Zijlstra2012-05-171-25/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It's been broken forever (i.e. it's not scheduling in a power aware fashion), as reported by Suresh and others sending patches, and nobody cares enough to fix it properly ... so remove it to make space free for something better. There's various problems with the code as it stands today, first and foremost the user interface which is bound to topology levels and has multiple values per level. This results in a state explosion which the administrator or distro needs to master and almost nobody does. Furthermore large configuration state spaces aren't good, it means the thing doesn't just work right because it's either under so many impossibe to meet constraints, or even if there's an achievable state workloads have to be aware of it precisely and can never meet it for dynamic workloads. So pushing this kind of decision to user-space was a bad idea even with a single knob - it's exponentially worse with knobs on every node of the topology. There is a proposal to replace the user interface with a single 3 state knob: sched_balance_policy := { performance, power, auto } where 'auto' would be the preferred default which looks at things like Battery/AC mode and possible cpufreq state or whatever the hw exposes to show us power use expectations - but there's been no progress on it in the past many months. Aside from that, the actual implementation of the various knobs is known to be broken. There have been sporadic attempts at fixing things but these always stop short of reaching a mergable state. Therefore this wholesale removal with the hopes of spurring people who care to come forward once again and work on a coherent replacement. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/1326104915.2442.53.camel@twins Signed-off-by: Ingo Molnar <mingo@kernel.org>
* Documentation, ABI: Update L3 cache index disable textBorislav Petkov2011-05-161-17/+17
| | | | | | | | | | | Change contact person to AMD kernel mailing list, update text and external references, drop "Users:" tag. Cc: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> Link: http://lkml.kernel.org/r/1305553188-21061-4-git-send-email-bp@amd64.org Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* Documentation: update broken web addresses.Justin P. Mattock2010-08-041-1/+1
| | | | | | | | | | | | | | | | | | Below you will find an updated version from the original series bunching all patches into one big patch updating broken web addresses that are located in Documentation/* Some of the addresses date as far far back as 1995 etc... so searching became a bit difficult, the best way to deal with these is to use web.archive.org to locate these addresses that are outdated. Now there are also some addresses pointing to .spec files some are located, but some(after searching on the companies site)where still no where to be found. In this case I just changed the address to the company site this way the users can contact the company and they can locate them for the users. Signed-off-by: Justin P. Mattock <justinmattock@gmail.com> Signed-off-by: Thomas Weber <weber@corscience.de> Signed-off-by: Mike Frysinger <vapier.adi@gmail.com> Cc: Paulo Marques <pmarques@grupopie.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Michael Neuling <mikey@neuling.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* Documentation: ABI: /sys/devices/system/cpu/cpu#/nodeAlex Chiang2009-12-151-0/+14
| | | | | | | | | | | | | | | Describe NUMA node symlink created for CPUs when CONFIG_NUMA is set. Signed-off-by: Alex Chiang <achiang@hp.com> Cc: Greg KH <greg@kroah.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Gary Hade <garyhade@us.ibm.com> Cc: Badari Pulavarty <pbadari@us.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Rientjes <rientjes@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'next' of ↵Linus Torvalds2009-12-121-0/+15
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (151 commits) powerpc: Fix usage of 64-bit instruction in 32-bit altivec code MAINTAINERS: Add PowerPC patterns powerpc/pseries: Track previous CPPR values to correctly EOI interrupts powerpc/pseries: Correct pseries/dlpar.c build break without CONFIG_SMP powerpc: Make "intspec" pointers in irq_host->xlate() const powerpc/8xx: DTLB Miss cleanup powerpc/8xx: Remove DIRTY pte handling in DTLB Error. powerpc/8xx: Start using dcbX instructions in various copy routines powerpc/8xx: Restore _PAGE_WRITETHRU powerpc/8xx: Add missing Guarded setting in DTLB Error. powerpc/8xx: Fixup DAR from buggy dcbX instructions. powerpc/8xx: Tag DAR with 0x00f0 to catch buggy instructions. powerpc/8xx: Update TLB asm so it behaves as linux mm expects. powerpc/8xx: Invalidate non present TLBs powerpc/pseries: Serialize cpu hotplug operations during deactivate Vs deallocate pseries/pseries: Add code to online/offline CPUs of a DLPAR node powerpc: stop_this_cpu: remove the cpu from the online map. powerpc/pseries: Add kernel based CPU DLPAR handling sysfs/cpu: Add probe/release files powerpc/pseries: Kernel DLPAR Infrastructure ...
| * sysfs/cpu: Add probe/release filesNathan Fontenot2009-12-091-0/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Version 3 of this patch is updated with documentation added to Documentation/ABI. There are no changes to any of the C code from v2 of the patch. In order to support kernel DLPAR of CPU resources we need to provide an interface to add (probe) and remove (release) the resource from the system. This patch Creates new generic probe and release sysfs files to facilitate cpu probe/release. The probe/release interface provides for allowing each arch to supply their own routines for implementing the backend of adding and removing cpus to/from the system. This also creates the powerpc specific stubs to handle the arch callouts from writes to the sysfs files. The creation and use of these files is regulated by the CONFIG_ARCH_CPU_PROBE_RELEASE option so that only architectures that need the capability will have the files created. Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* | [CPUFREQ] Documentation: ABI: /sys/devices/system/cpu/cpu#/cpufreq/Alex Chiang2009-11-241-0/+18
|/ | | | | | | | | | | This is a complex interface and is already described in Documentation/cpu-freq/, especially in the user-guide.txt file. No need to copy/paste all that information. Let's just alert the reader to the presence of the user-guide. Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Dave Jones <davej@redhat.com>
* Documentation: ABI: /sys/devices/system/cpu/cpu#/nodeAlex Chiang2009-10-301-0/+15
| | | | | | | | | Describe NUMA node symlink created for CPUs when CONFIG_NUMA is set. Cc: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Documentation: ABI: /sys/devices/system/cpu/cpuidle/Alex Chiang2009-10-301-0/+20
| | | | | | | | | | | Document cpuidle sysfs attributes by reading code, Documentation/cpuidle/, and git logs. Cc: Venki Pallipadi <venkatesh.pallipadi@intel.com> Cc: Len Brown <lenb@kernel.org> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Documentation: ABI: /sys/devices/system/cpu/sched_[mc|smt]_power_savingsAlex Chiang2009-10-301-0/+24
| | | | | | | | | | | Document sched_[mc|smt]_power_savings by reading existing code and git logs. Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Documentation: ABI: /sys/devices/system/cpu/cpu#/ topology filesAlex Chiang2009-10-301-0/+39
| | | | | | | | | | | | | | | | | | | | | | | | Add brief descriptions for the following sysfs files: /sys/devices/system/cpu/cpu#/topology/core_id /sys/devices/system/cpu/cpu#/topology/core_siblings /sys/devices/system/cpu/cpu#/topology/core_siblings_list /sys/devices/system/cpu/cpu#/topology/physical_package_id /sys/devices/system/cpu/cpu#/topology/thread_siblings /sys/devices/system/cpu/cpu#/topology/thread_siblings_list The descriptions in Documentation/cputopology.txt weren't very informative, so I attempted a better description based on code reading and hopeful guessing. Updated Documentation/cputopology.txt with the better descriptions and fixed some style issues. Cc: Mike Travis <travis@sgi.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Documentation: ABI: /sys/devices/system/cpu/ topology filesAlex Chiang2009-10-301-0/+28
| | | | | | | | | | | | | | | | | | | | Add brief descriptions for the following sysfs files: /sys/devices/system/cpu/kernel_max /sys/devices/system/cpu/offline /sys/devices/system/cpu/online /sys/devices/system/cpu/possible /sys/devices/system/cpu/present Excerpted the relevant information from Documentation/cputopology.txt and pointed back to cputopology.txt as the authoritative source of information. Cc: Mike Travis <travis@sgi.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Documentation: ABI: document /sys/devices/system/cpu/Alex Chiang2009-10-301-0/+12
| | | | | | | | | | | This interface has been around for a long time, but hasn't been officially documented. Document the top level sysfs directory for CPU attributes. Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Documentation: ABI: rename sysfs-devices-cache_disable properlyAlex Chiang2009-10-301-0/+18
Rename sysfs-devices-cache_disable to sysfs-devices-system-cpu, in order to keep a stricter correlation between a sysfs directory and its documentation. Reported-by: David Rientjes <rientjes@google.com> Signed-off-by: Alex Chiang <achiang@hp.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>