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2022-05-25Merge tag 'docs-5.19' of git://git.lwn.net/linuxLinus Torvalds1-1/+1
Pull documentation updates from Jonathan Corbet: "It was a moderately busy cycle for documentation; highlights include: - After a long period of inactivity, the Japanese translations are seeing some much-needed maintenance and updating. - Reworked IOMMU documentation - Some new documentation for static-analysis tools - A new overall structure for the memory-management documentation. This is an LSFMM outcome that, it is hoped, will help encourage developers to fill in the many gaps. Optimism is eternal...but hopefully it will work. - More Chinese translations. Plus the usual typo fixes, updates, etc" * tag 'docs-5.19' of git://git.lwn.net/linux: (70 commits) docs: pdfdocs: Add space for chapter counts >= 100 in TOC docs/zh_CN: Add dev-tools/gdb-kernel-debugging.rst Chinese translation input: Docs: correct ntrig.rst typo input: Docs: correct atarikbd.rst typos MAINTAINERS: Become the docs/zh_CN maintainer docs/zh_CN: fix devicetree usage-model translation mm,doc: Add new documentation structure Documentation: drop more IDE boot options and ide-cd.rst Documentation/process: use scripts/get_maintainer.pl on patches MAINTAINERS: Add entry for DOCUMENTATION/JAPANESE docs/trans/ja_JP/howto: Don't mention specific kernel versions docs/ja_JP/SubmittingPatches: Request summaries for commit references docs/ja_JP/SubmittingPatches: Add Suggested-by as a standard signature docs/ja_JP/SubmittingPatches: Randy has moved docs/ja_JP/SubmittingPatches: Suggest the use of scripts/get_maintainer.pl docs/ja_JP/SubmittingPatches: Update GregKH links Documentation/sysctl: document max_rcu_stall_to_panic Documentation: add missing angle bracket in cgroup-v2 doc Documentation: dev-tools: use literal block instead of code-block docs/zh_CN: add vm numa translation ...
2022-05-23Merge tag 'platform-drivers-x86-v5.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86Linus Torvalds1-0/+1
Pull x86 platform driver updates from Hans de Goede: "This includes some small changes to kernel/stop_machine.c and arch/x86 which are deps of the new Intel IFS support. Highlights: - New drivers: - Intel "In Field Scan" (IFS) support - Winmate FM07/FM07P buttons - Mellanox SN2201 support - AMD PMC driver enhancements - Lots of various other small fixes and hardware-id additions" * tag 'platform-drivers-x86-v5.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86: (54 commits) platform/x86/intel/ifs: Add CPU_SUP_INTEL dependency platform/x86: intel_cht_int33fe: Set driver data platform/x86: intel-hid: fix _DSM function index handling platform/x86: toshiba_acpi: use kobj_to_dev() platform/x86: samsung-laptop: use kobj_to_dev() platform/x86: gigabyte-wmi: Add support for Z490 AORUS ELITE AC and X570 AORUS ELITE WIFI tools/power/x86/intel-speed-select: Fix warning for perf_cap.cpu tools/power/x86/intel-speed-select: Display error on turbo mode disabled Documentation: In-Field Scan platform/x86/intel/ifs: add ABI documentation for IFS trace: platform/x86/intel/ifs: Add trace point to track Intel IFS operations platform/x86/intel/ifs: Add IFS sysfs interface platform/x86/intel/ifs: Add scan test support platform/x86/intel/ifs: Authenticate and copy to secured memory platform/x86/intel/ifs: Check IFS Image sanity platform/x86/intel/ifs: Read IFS firmware image platform/x86/intel/ifs: Add stub driver for In-Field Scan stop_machine: Add stop_core_cpuslocked() for per-core operations x86/msr-index: Define INTEGRITY_CAPABILITIES MSR x86/microcode/intel: Expose collect_cpu_info_early() for IFS ...
2022-05-12Documentation: In-Field ScanTony Luck1-0/+1
Add documentation for In-Field Scan (IFS). This documentation describes the basics of IFS, the loading IFS image, chunk authentication, running scan and how to check result via sysfs. The CORE_CAPABILITIES MSR enumerates whether IFS is supported. The full github location for distributing the IFS images is still being decided. So just a placeholder included for now in the documentation. Future CPUs will support more than one type of test. Plan for that now by using a "_0" suffix on the ABI directory names. Additional test types will use "_1", etc. Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20220506225410.1652287-13-tony.luck@intel.com Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2022-04-28Documentation: x86: rework IOMMU documentationAlex Deucher1-1/+1
Add preliminary documentation for AMD IOMMU and combine with the existing Intel IOMMU documentation and clean up and modernize some of the existing documentation to align with the current state of the kernel. Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Acked-by: Joerg Roedel <jroedel@suse.de> Link: https://lore.kernel.org/r/20220422192656.624920-1-alexander.deucher@amd.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-04-08Documentation/x86: Document TDX kernel architectureKuppuswamy Sathyanarayanan1-0/+1
Document the TDX guest architecture details like #VE support, shared memory, etc. [ dhansen: made some wording changes, including removing all the plural "#VE's" and "#VEs". ] Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lkml.kernel.org/r/20220405232939.73860-31-kirill.shutemov@linux.intel.com
2022-03-25Merge tag 'platform-drivers-x86-v5.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86Linus Torvalds1-0/+1
Pull x86 platform driver updates from Hans de Goede: "New drivers: - AMD Host System Management Port (HSMP) - Intel Software Defined Silicon Removed drivers (functionality folded into other drivers): - intel_cht_int33fe_microb - surface3_button amd-pmc: - s2idle bug-fixes - Support for AMD Spill to DRAM STB feature hp-wmi: - Fix SW_TABLET_MODE detection method (and other fixes) - Support omen thermal profile policy v1 serial-multi-instantiate: - Add SPI device support - Add support for CS35L41 amplifiers used in new laptops think-lmi: - syfs-class-firmware-attributes Certificate authentication support thinkpad_acpi: - Fixes + quirks - Add platform_profile support on AMD based ThinkPads x86-android-tablets: - Improve Asus ME176C / TF103C support - Support Nextbook Ares 8, Lenovo Tab 2 830 and 1050 tablets Lots of various other small fixes and hardware-id additions" * tag 'platform-drivers-x86-v5.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86: (60 commits) platform/x86: think-lmi: Certificate authentication support Documentation: syfs-class-firmware-attributes: Lenovo Certificate support platform/x86: amd-pmc: Only report STB errors when STB enabled platform/x86: amd-pmc: Drop CPU QoS workaround platform/x86: amd-pmc: Output error codes in messages platform/x86: amd-pmc: Move to later in the suspend process ACPI / x86: Add support for LPS0 callback handler platform/x86: thinkpad_acpi: consistently check fan_get_status return. platform/x86: hp-wmi: support omen thermal profile policy v1 platform/x86: hp-wmi: Changing bios_args.data to be dynamically allocated platform/x86: hp-wmi: Fix 0x05 error code reported by several WMI calls platform/x86: hp-wmi: Fix SW_TABLET_MODE detection method platform/x86: hp-wmi: Fix hp_wmi_read_int() reporting error (0x05) platform/x86: amd-pmc: Validate entry into the deepest state on resume platform/x86: thinkpad_acpi: Don't use test_bit on an integer platform/x86: thinkpad_acpi: Fix compiler warning about uninitialized err variable platform/x86: thinkpad_acpi: clean up dytc profile convert platform/x86: x86-android-tablets: Depend on EFI and SPI platform/x86: amd-pmc: uninitialized variable in amd_pmc_s2d_init() platform/x86: intel-uncore-freq: fix uncore_freq_common_init() error codes ...
2022-03-02Documentation: Add x86/amd_hsmp driverNaveen Krishna Chatradhi1-0/+1
This documentation for amd_hsmp driver explains how to use the device interface. Signed-off-by: Naveen Krishna Chatradhi <nchatrad@amd.com> Acked-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20220222050501.18789-2-nchatrad@amd.com Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2022-02-03x86/Documentation: Describe the Intel Hardware Feedback InterfaceRicardo Neri1-0/+1
Start a documentation file to describe the purpose and operation of Intel's Hardware Feedback Interface. Describe how this interface is used in Linux to relay performance and energy efficiency updates to userspace. Reviewed-by: Len Brown <len.brown@intel.com> Suggested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-10-28Documentation/x86: Add documentation for using dynamic XSTATE featuresChang S. Bae1-0/+1
Explain how dynamic XSTATE features can be enabled via the architecture-specific prctl() along with dynamic sigframe size and first use trap handling. Fix: Documentation/x86/xstate.rst:15: WARNING: Title underline too short. as reported by Stephen Rothwell <sfr@canb.auug.org.au> Originally-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20211026091157.16711-1-chang.seok.bae@intel.com
2021-07-07Merge tag 'x86-fpu-2021-07-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-0/+1
Pull x86 fpu updates from Thomas Gleixner: "Fixes and improvements for FPU handling on x86: - Prevent sigaltstack out of bounds writes. The kernel unconditionally writes the FPU state to the alternate stack without checking whether the stack is large enough to accomodate it. Check the alternate stack size before doing so and in case it's too small force a SIGSEGV instead of silently corrupting user space data. - MINSIGSTKZ and SIGSTKSZ are constants in signal.h and have never been updated despite the fact that the FPU state which is stored on the signal stack has grown over time which causes trouble in the field when AVX512 is available on a CPU. The kernel does not expose the minimum requirements for the alternate stack size depending on the available and enabled CPU features. ARM already added an aux vector AT_MINSIGSTKSZ for the same reason. Add it to x86 as well. - A major cleanup of the x86 FPU code. The recent discoveries of XSTATE related issues unearthed quite some inconsistencies, duplicated code and other issues. The fine granular overhaul addresses this, makes the code more robust and maintainable, which allows to integrate upcoming XSTATE related features in sane ways" * tag 'x86-fpu-2021-07-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (74 commits) x86/fpu/xstate: Clear xstate header in copy_xstate_to_uabi_buf() again x86/fpu/signal: Let xrstor handle the features to init x86/fpu/signal: Handle #PF in the direct restore path x86/fpu: Return proper error codes from user access functions x86/fpu/signal: Split out the direct restore code x86/fpu/signal: Sanitize copy_user_to_fpregs_zeroing() x86/fpu/signal: Sanitize the xstate check on sigframe x86/fpu/signal: Remove the legacy alignment check x86/fpu/signal: Move initial checks into fpu__restore_sig() x86/fpu: Mark init_fpstate __ro_after_init x86/pkru: Remove xstate fiddling from write_pkru() x86/fpu: Don't store PKRU in xstate in fpu_reset_fpstate() x86/fpu: Remove PKRU handling from switch_fpu_finish() x86/fpu: Mask PKRU from kernel XRSTOR[S] operations x86/fpu: Hook up PKRU into ptrace() x86/fpu: Add PKRU storage outside of task XSAVE buffer x86/fpu: Dont restore PKRU in fpregs_restore_userspace() x86/fpu: Rename xfeatures_mask_user() to xfeatures_mask_uabi() x86/fpu: Move FXSAVE_LEAK quirk info __copy_kernel_to_fpregs() x86/fpu: Rename __fpregs_load_activate() to fpregs_restore_userregs() ...
2021-05-19x86/elf: Support a new ELF aux vector AT_MINSIGSTKSZChang S. Bae1-0/+1
Historically, signal.h defines MINSIGSTKSZ (2KB) and SIGSTKSZ (8KB), for use by all architectures with sigaltstack(2). Over time, the hardware state size grew, but these constants did not evolve. Today, literal use of these constants on several architectures may result in signal stack overflow, and thus user data corruption. A few years ago, the ARM team addressed this issue by establishing getauxval(AT_MINSIGSTKSZ). This enables the kernel to supply a value at runtime that is an appropriate replacement on current and future hardware. Add getauxval(AT_MINSIGSTKSZ) support to x86, analogous to the support added for ARM in 94b07c1f8c39 ("arm64: signal: Report signal frame size to userspace via auxv"). Also, include a documentation to describe x86-specific auxiliary vectors. Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Len Brown <len.brown@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20210518200320.17239-4-chang.seok.bae@intel.com
2021-05-18Documentation/x86: Add buslock.rstFenghua Yu1-0/+1
Add buslock.rst to explain bus lock problem and how to detect and handle it. [ tglx: Included it into index.rst and added the missing include ... ] Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Link: https://lore.kernel.org/r/20210419214958.4035512-2-fenghua.yu@intel.com
2020-12-14Merge tag 'docs-5.11' of git://git.lwn.net/linuxLinus Torvalds1-0/+1
Pull documentation updates from Jonathan Corbet: "A much quieter cycle for documentation (happily), with, one hopes, the bulk of the churn behind us. Significant stuff in this pull includes: - A set of new Chinese translations - Italian translation updates - A mechanism from Mauro to automatically format Documentation/features for the built docs - Automatic cross references without explicit :ref: markup - A new reset-controller document - An extensive new document on reporting problems from Thorsten That last patch also adds the CC-BY-4.0 license to LICENSES/dual; there was some discussion on this, but we seem to have consensus and an ack from Greg for that addition" * tag 'docs-5.11' of git://git.lwn.net/linux: (50 commits) docs: fix broken cross reference in translations/zh_CN docs: Note that sphinx 1.7 will be required soon docs: update requirements to install six module docs: reporting-issues: move 'outdated, need help' note to proper place docs: Update documentation to reflect what TAINT_CPU_OUT_OF_SPEC means docs: add a reset controller chapter to the driver API docs docs: make reporting-bugs.rst obsolete docs: Add a new text describing how to report bugs LICENSES: Add the CC-BY-4.0 license Documentation: fix multiple typos found in the admin-guide subdirectory Documentation: fix typos found in admin-guide subdirectory kernel-doc: Fix example in Nested structs/unions docs: clean up sysctl/kernel: titles, version docs: trace: fix event state structure name docs: nios2: add missing ReST file scripts: get_feat.pl: reduce table width for all features output scripts: get_feat.pl: change the group by order scripts: get_feat.pl: make complete table more coincise scripts: kernel-doc: fix parsing function-like typedefs Documentation: fix typos found in process, dev-tools, and doc-guide subdirectories ...
2020-12-14Merge tag 'x86_cache_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-1/+1
Pull x86 cache resource control updates from Borislav Petkov: - add logic to correct MBM total and local values fixing errata SKX99 and BDF102 (Fenghua Yu) - cleanups * tag 'x86_cache_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/resctrl: Clean up unused function parameter in rmdir path x86/resctrl: Constify kernfs_ops x86/resctrl: Correct MBM total and local values Documentation/x86: Rename resctrl_ui.rst and add two errata to the file
2020-12-03docs: archis: add a per-architecture features listMauro Carvalho Chehab1-0/+1
Add a feature list matrix for each architecture to their respective Kernel books. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/9c39d4dd93e05c0008205527d2c3450912f029ed.1606748711.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-11-18Documentation/x86: Document SGX kernel architectureJarkko Sakkinen1-0/+1
Document the Intel SGX kernel architecture. The fine-grained architecture details can be looked up from Intel SDM Volume 3D. Co-developed-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Jethro Beekman <jethro@fortanix.com> Cc: linux-doc@vger.kernel.org Link: https://lkml.kernel.org/r/20201112220135.165028-24-jarkko@kernel.org
2020-10-27Documentation/x86: Rename resctrl_ui.rst and add two errata to the fileFenghua Yu1-1/+1
Intel Memory Bandwidth Monitoring (MBM) counters may report system memory bandwidth incorrectly on some Intel processors. This is reported in documented in erratum SKX99, erratum BDF102 and in the RDT reference manual, see Documentation/x86/index.rst. To work around the errata, MBM total and local readings are corrected using a correction factor table. Since the correction factor table is not publicly documented anywhere, document the table and the errata in Documentation/x86/resctrl.rst for future reference. [ bp: Move web links to the doc, massage. ] Suggested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Link: https://lkml.kernel.org/r/20201014004927.1839452-2-fenghua.yu@intel.com
2020-10-14Merge tag 'devicetree-for-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linuxLinus Torvalds1-0/+1
Pull devicetree updates from Rob Herring: - Update dtc to upstream version v1.6.0-31-gcbca977ea121 - dtx_diff help text reformatting - Speed-up validation time for binding and dtb checks using json for intermediate files - Add support for running yamllint on DT schema files - Remove old booting-without-of.rst - Extend the example schema to address common issues - Cleanup handling of additionalProperties/unevaluatedProperties - Ensure all DSI controller schemas reference dsi-controller.yaml - Vendor prefixes for Zealz, Wandbord/Technexion, Embest RIoT, Rex, DFI, and Cisco Meraki - Convert at25, SPMI bus, TI hwlock, HiSilicon Hi3660 USB3 PHY, Arm SP805 watchdog, Arm SP804, and Samsung 11-pin USB connector to DT schema - Convert HiSilicon SoC and syscon bindings to DT schema - Convert SiFive Risc-V L2 cache, PLIC, PRCI, and PWM to DT schema - Convert i.MX bindings for w1, crypto, rng, SIM, PM, DDR, SATA, vf610 GPIO, and UART to DT schema - Add i.MX 8M compatible strings - Add LM81 and DS1780 as trivial devices - Various missing properties added to fix dtb validation warnings * tag 'devicetree-for-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (111 commits) dt-bindings: misc: explicitly add #address-cells for slave mode spi: dt-bindings: spi-controller: explicitly require #address-cells=<0> for slave mode dt: Remove booting-without-of.rst dt-bindings: update usb-c-connector example dt-bindings: arm: hisilicon: add missing properties into cpuctrl.yaml dt-bindings: arm: hisilicon: add missing properties into sysctrl.yaml dt-bindings: pwm: imx: document i.MX compatibles scripts/dtc: Update to upstream version v1.6.0-31-gcbca977ea121 dt-bindings: Add running yamllint to dt_binding_check dt-bindings: powerpc: Add a schema for the 'sleep' property dt-bindings: pinctrl: sirf: Fix typo abitrary dt-bindings: pinctrl: qcom: Fix typo abitrary dt-bindings: Explicitly allow additional properties in common schemas dt-bindings: Use 'additionalProperties' instead of 'unevaluatedProperties' dt-bindings: Add missing 'unevaluatedProperties' Docs: Fixing spelling errors in Documentation/devicetree/bindings/ dt-bindings: arm: hisilicon: convert Hi6220 domain controller bindings to json-schema dt-bindings: riscv: convert pwm bindings to json-schema dt-bindings: riscv: convert plic bindings to json-schema dt-bindings: fu540: prci: convert PRCI bindings to json-schema ...
2020-10-13dt: Remove booting-without-of.rstRob Herring1-0/+1
booting-without-of.rst is an ancient document that first outlined Flattened DeviceTree on PowerPC initially. The DT world has evolved a lot in the 15 years since and booting-without-of.rst is pretty stale. The name of the document itself is confusing if you don't understand the evolution from real 'OpenFirmware'. Most of what booting-without-of.rst contains is now in the DT specification (which evolved out of the ePAPR). The few things that weren't documented in the DT specification are now. All that remains is the boot entry details, so let's move these to arch specific documents. The exception is arm which already has the same details documented. Cc: Frank Rowand <frowand.list@gmail.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Paul Mackerras <paulus@samba.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Rich Felker <dalias@libc.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-mips@vger.kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-sh@vger.kernel.org Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Borislav Petkov <bp@suse.de> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Signed-off-by: Rob Herring <robh@kernel.org>
2020-10-12Merge tag 'x86_misc_for_v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-0/+1
Pull misc x86 fixes fromm Borislav Petkov: - Ratelimit the message about writes to unrecognized MSRs so that they don't spam the console log (Chris Down) - Document how the /proc/cpuinfo machinery works for future reference (Kyung Min Park, Ricardo Neri and Dave Hansen) - Correct the current NMI's duration calculation (Libing Zhou) * tag 'x86_misc_for_v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/nmi: Fix nmi_handle() duration miscalculation Documentation/x86: Add documentation for /proc/cpuinfo feature flags x86/msr: Make source of unrecognised MSR writes unambiguous x86/msr: Prevent userspace MSR access from dominating the console
2020-09-17Documentation/x86: Add documentation for SVA (Shared Virtual Addressing)Ashok Raj1-0/+1
ENQCMD and Data Streaming Accelerator (DSA) and all of their associated features are a complicated stack with lots of interconnected pieces. This documentation provides a big picture overview for all of the features. Signed-off-by: Ashok Raj <ashok.raj@intel.com> Co-developed-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Link: https://lkml.kernel.org/r/1600187413-163670-4-git-send-email-fenghua.yu@intel.com
2020-09-01Documentation/x86: Add documentation for /proc/cpuinfo feature flagsKyung Min Park1-0/+1
/proc/cpuinfo shows features which the kernel supports. Some of these flags are derived from CPUID, and others are derived from other sources, including some that are entirely software-based. Currently, there is not any documentation in the kernel about how /proc/cpuinfo flags are generated and what it means when they are missing. Add documentation for /proc/cpuinfo feature flags enumeration. Document how and when x86 feature flags are used. Also discuss what their presence or absence mean for the kernel and users. Suggested-by: Dave Hansen <dave.hansen@intel.com> Co-developed-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Signed-off-by: Kyung Min Park <kyung.min.park@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Link: https://lkml.kernel.org/r/20200831183500.15481-1-kyung.min.park@intel.com
2020-02-25docs: remove MPX from the x86 tocStephen Kitt1-1/+0
MPX was removed in commit 45fc24e89b7c ("x86/mpx: remove MPX from arch/x86"), this removes the corresponding entry in the x86 toc. This was suggested by a Sphinx warning. Signed-off-by: Stephen Kitt <steve@sk2.org> Fixes: 45fc24e89b7cc ("x86/mpx: remove MPX from arch/x86") Acked-by: Dave Hansen <dave.hansen@intel.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-10-28x86/speculation/taa: Add documentation for TSX Async AbortPawan Gupta1-0/+1
Add the documenation for TSX Async Abort. Include the description of the issue, how to check the mitigation state, control the mitigation, guidance for system administrators. [ bp: Add proper SPDX tags, touch ups by Josh and me. ] Co-developed-by: Antonio Gomez Iglesias <antonio.gomez.iglesias@intel.com> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Antonio Gomez Iglesias <antonio.gomez.iglesias@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Mark Gross <mgross@linux.intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
2019-07-15docs: x86: move two x86-specific files to x86 arch dirMauro Carvalho Chehab1-0/+2
Those two docs belong to the x86 architecture: Documentation/Intel-IOMMU.txt -> Documentation/x86/intel-iommu.rst Documentation/intel_txt.txt -> Documentation/x86/intel_txt.rst Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-06-08docs: move protection-keys.rst to the core-api bookMauro Carvalho Chehab1-1/+0
This document is used by multiple architectures: $ echo $(git grep -l pkey_mprotect arch|cut -d'/' -f 2|sort|uniq) alpha arm arm64 ia64 m68k microblaze mips parisc powerpc s390 sh sparc x86 xtensa So, let's move it to the core book and adjust the links to it accordingly. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-14Merge branch 'x86-mds-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-0/+1
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 ...
2019-05-08Documentation: x86: convert x86_64/boot-options.txt to reSTChangbin Du1-0/+1
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: x86: convert i386/IO-APIC.txt to reSTChangbin Du1-0/+1
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: x86: convert usb-legacy-support.txt to reSTChangbin Du1-0/+1
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: x86: convert orc-unwinder.txt to reSTChangbin Du1-0/+1
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: x86: convert resctrl_ui.txt to reSTChangbin Du1-0/+1
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: x86: convert microcode.txt to reSTChangbin Du1-0/+1
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: x86: convert pti.txt to reSTChangbin Du1-0/+1
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: x86: convert amd-memory-encryption.txt to reSTChangbin Du1-0/+1
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: x86: convert intel_mpx.txt to reSTChangbin Du1-0/+1
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: x86: convert protection-keys.txt to reSTChangbin Du1-0/+1
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: x86: convert pat.txt to reSTChangbin Du1-0/+1
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: x86: convert mtrr.txt to reSTChangbin Du1-0/+1
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: x86: convert tlb.txt to reSTChangbin Du1-0/+1
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: x86: convert zero-page.txt to reSTChangbin Du1-0/+1
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: x86: convert earlyprintk.txt to reSTChangbin Du1-0/+1
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: x86: convert entry_64.txt to reSTChangbin Du1-0/+1
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: x86: convert kernel-stacks to reSTChangbin Du1-0/+1
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: x86: convert exception-tables.txt to reSTChangbin Du1-0/+1
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: x86: convert topology.txt to reSTChangbin Du1-0/+1
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: x86: convert boot.txt to reSTChangbin Du1-0/+2
This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du <changbin.du@gmail.com> Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-08Documentation: add Linux x86 docs to Sphinx TOC treeChangbin Du1-0/+9
Add a index.rst for x86 support. More docs will be added later. Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-03-06x86/speculation/mds: Add mds_clear_cpu_buffers()Thomas Gleixner1-0/+8
The Microarchitectural Data Sampling (MDS) vulernabilities are mitigated by clearing the affected CPU buffers. The mechanism for clearing the buffers uses the unused and obsolete VERW instruction in combination with a microcode update which triggers a CPU buffer clear when VERW is executed. Provide a inline function with the assembly magic. The argument of the VERW instruction must be a memory operand as documented: "MD_CLEAR enumerates that the memory-operand variant of VERW (for example, VERW m16) has been extended to also overwrite buffers affected by MDS. This buffer overwriting functionality is not guaranteed for the register operand variant of VERW." Documentation also recommends to use a writable data segment selector: "The buffer overwriting occurs regardless of the result of the VERW permission check, as well as when the selector is null or causes a descriptor load segment violation. However, for lowest latency we recommend using a selector that indicates a valid writable data segment." Add x86 specific documentation about MDS and the internal workings of the mitigation. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Reviewed-by: Jon Masters <jcm@redhat.com> Tested-by: Jon Masters <jcm@redhat.com>