Commit Graph

430 Commits

Author SHA1 Message Date
Mauro Carvalho Chehab d6a21f2d73 objtool: update objtool.txt references
Changeset a8e35fece4 ("objtool: Update documentation")
renamed: tools/objtool/Documentation/stack-validation.txt
to: tools/objtool/Documentation/objtool.txt.

Update the cross-references accordingly.

Fixes: a8e35fece4 ("objtool: Update documentation")
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Link: https://lore.kernel.org/r/ec285ece6348a5be191aebe45f78d06b3319056b.1656234456.git.mchehab@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-07-07 13:10:00 -06:00
Linus Torvalds 88a618920e 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.
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Merge tag 'docs-5.19' of git://git.lwn.net/linux

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
  ...
2022-05-25 11:17:41 -07:00
Linus Torvalds 8443516da6 platform-drivers-x86 for v5.19-1
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
 
 The following is an automated git shortlog grouped by driver:
 
 Documentation:
  -  In-Field Scan
 
 Documentation/ABI:
  -  Add new attributes for mlxreg-io sysfs interfaces
  -  sysfs-class-firmware-attributes: Misc. cleanups
  -  sysfs-class-firmware-attributes: Fix Sphinx errors
  -  sysfs-driver-intel_sdsi: Fix sphinx warnings
 
 acerhdf:
  -  Cleanup str_starts_with()
 
 amd-pmc:
  -  Fix build error unused-function
  -  Shuffle location of amd_pmc_get_smu_version()
  -  Avoid reading SMU version at probe time
  -  Move FCH init to first use
  -  Move SMU logging setup out of init
  -  Fix compilation without CONFIG_SUSPEND
 
 amd_hsmp:
  -  Add HSMP protocol version 5 messages
 
 asus-nb-wmi:
  -  Add keymap for MyASUS key
 
 asus-wmi:
  -  Update unknown code message
  -  Use kobj_to_dev()
  -  Fix driver not binding when fan curve control probe fails
  -  Potential buffer overflow in asus_wmi_evaluate_method_buf()
 
 barco-p50-gpio:
  -  Fix duplicate included linux/io.h
 
 dell-laptop:
  -  Add quirk entry for Latitude 7520
 
 gigabyte-wmi:
  -  Add support for Z490 AORUS ELITE AC and X570 AORUS ELITE WIFI
  -  added support for B660 GAMING X DDR4 motherboard
 
 hp-wmi:
  -  Correct code style related issues
 
 intel-hid:
  -  fix _DSM function index handling
 
 intel-uncore-freq:
  -  Prevent driver loading in guests
 
 intel_cht_int33fe:
  -  Set driver data
 
 platform/mellanox:
  -  Add support for new SN2201 system
 
 platform/surface:
  -  aggregator: Fix initialization order when compiling as builtin module
  -  gpe: Add support for Surface Pro 8
 
 platform/x86/dell:
  -  add buffer allocation/free functions for SMI calls
 
 platform/x86/intel:
  -  Fix 'rmmod pmt_telemetry' panic
  -  pmc/core: Use kobj_to_dev()
  -  pmc/core: change pmc_lpm_modes to static
 
 platform/x86/intel/ifs:
  -  Add CPU_SUP_INTEL dependency
  -  add ABI documentation for IFS
  -  Add IFS sysfs interface
  -  Add scan test support
  -  Authenticate and copy to secured memory
  -  Check IFS Image sanity
  -  Read IFS firmware image
  -  Add stub driver for In-Field Scan
 
 platform/x86/intel/sdsi:
  -  Fix bug in multi packet reads
  -  Poll on ready bit for writes
  -  Handle leaky bucket
 
 platform_data/mlxreg:
  -  Add field for notification callback
 
 pmc_atom:
  -  dont export pmc_atom_read - no modular users
  -  remove unused pmc_atom_write()
 
 samsung-laptop:
  -  use kobj_to_dev()
  -  Fix an unsigned comparison which can never be negative
 
 stop_machine:
  -  Add stop_core_cpuslocked() for per-core operations
 
 think-lmi:
  -  certificate support clean ups
 
 thinkpad_acpi:
  -  Correct dual fan probe
  -  Add a s2idle resume quirk for a number of laptops
  -  Convert btusb DMI list to quirks
 
 tools/power/x86/intel-speed-select:
  -  Fix warning for perf_cap.cpu
  -  Display error on turbo mode disabled
  -  fix build failure when using -Wl,--as-needed
 
 toshiba_acpi:
  -  use kobj_to_dev()
 
 trace:
  -  platform/x86/intel/ifs: Add trace point to track Intel IFS operations
 
 winmate-fm07-keys:
  -  Winmate FM07/FM07P buttons
 
 wmi:
  -  replace usage of found with dedicated list iterator variable
 
 x86/microcode/intel:
  -  Expose collect_cpu_info_early() for IFS
 
 x86/msr-index:
  -  Define INTEGRITY_CAPABILITIES MSR
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Merge tag 'platform-drivers-x86-v5.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86

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
  ...
2022-05-23 20:38:39 -07:00
Linus Torvalds c5a3d3c01e - Remove a bunch of chicken bit options to turn off CPU features which
are not really needed anymore
 
 - Misc fixes and cleanups
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Merge tag 'x86_cpu_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 CPU feature updates from Borislav Petkov:

 - Remove a bunch of chicken bit options to turn off CPU features which
   are not really needed anymore

 - Misc fixes and cleanups

* tag 'x86_cpu_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/speculation: Add missing prototype for unpriv_ebpf_notify()
  x86/pm: Fix false positive kmemleak report in msr_build_context()
  x86/speculation/srbds: Do not try to turn mitigation off when not supported
  x86/cpu: Remove "noclflush"
  x86/cpu: Remove "noexec"
  x86/cpu: Remove "nosmep"
  x86/cpu: Remove CONFIG_X86_SMAP and "nosmap"
  x86/cpu: Remove "nosep"
  x86/cpu: Allow feature bit names from /proc/cpuinfo in clearcpuid=
2022-05-23 18:01:31 -07:00
Linus Torvalds 3a755ebcc2 Intel Trust Domain Extensions
This is the Intel version of a confidential computing solution called
 Trust Domain Extensions (TDX). This series adds support to run the
 kernel as part of a TDX guest. It provides similar guest protections to
 AMD's SEV-SNP like guest memory and register state encryption, memory
 integrity protection and a lot more.
 
 Design-wise, it differs from AMD's solution considerably: it uses
 a software module which runs in a special CPU mode called (Secure
 Arbitration Mode) SEAM. As the name suggests, this module serves as sort
 of an arbiter which the confidential guest calls for services it needs
 during its lifetime.
 
 Just like AMD's SNP set, this series reworks and streamlines certain
 parts of x86 arch code so that this feature can be properly accomodated.
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Merge tag 'x86_tdx_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull Intel TDX support from Borislav Petkov:
 "Intel Trust Domain Extensions (TDX) support.

  This is the Intel version of a confidential computing solution called
  Trust Domain Extensions (TDX). This series adds support to run the
  kernel as part of a TDX guest. It provides similar guest protections
  to AMD's SEV-SNP like guest memory and register state encryption,
  memory integrity protection and a lot more.

  Design-wise, it differs from AMD's solution considerably: it uses a
  software module which runs in a special CPU mode called (Secure
  Arbitration Mode) SEAM. As the name suggests, this module serves as
  sort of an arbiter which the confidential guest calls for services it
  needs during its lifetime.

  Just like AMD's SNP set, this series reworks and streamlines certain
  parts of x86 arch code so that this feature can be properly
  accomodated"

* tag 'x86_tdx_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits)
  x86/tdx: Fix RETs in TDX asm
  x86/tdx: Annotate a noreturn function
  x86/mm: Fix spacing within memory encryption features message
  x86/kaslr: Fix build warning in KASLR code in boot stub
  Documentation/x86: Document TDX kernel architecture
  ACPICA: Avoid cache flush inside virtual machines
  x86/tdx/ioapic: Add shared bit for IOAPIC base address
  x86/mm: Make DMA memory shared for TD guest
  x86/mm/cpa: Add support for TDX shared memory
  x86/tdx: Make pages shared in ioremap()
  x86/topology: Disable CPU online/offline control for TDX guests
  x86/boot: Avoid #VE during boot for TDX platforms
  x86/boot: Set CR0.NE early and keep it set during the boot
  x86/acpi/x86/boot: Add multiprocessor wake-up support
  x86/boot: Add a trampoline for booting APs via firmware handoff
  x86/tdx: Wire up KVM hypercalls
  x86/tdx: Port I/O: Add early boot support
  x86/tdx: Port I/O: Add runtime hypercalls
  x86/boot: Port I/O: Add decompression-time support for TDX
  x86/boot: Port I/O: Allow to hook up alternative helpers
  ...
2022-05-23 17:51:12 -07:00
Tony Luck 34604d2891 Documentation: In-Field Scan
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>
2022-05-12 15:35:29 +02:00
Alex Deucher 2a8d78d566 Documentation: x86: rework IOMMU documentation
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>
2022-04-28 07:59:45 -06:00
Kuppuswamy Sathyanarayanan b9c7ba5877 Documentation/x86: Document TDX kernel architecture
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
2022-04-08 06:57:09 -07:00
Michael Roth ba37a1438a x86/sev: Add a sev= cmdline option
For debugging purposes it is very useful to have a way to see the full
contents of the SNP CPUID table provided to a guest. Add an sev=debug
kernel command-line option to do so.

Also introduce some infrastructure so that additional options can be
specified via sev=option1[,option2] over time in a consistent manner.

  [ bp: Massage, simplify string parsing. ]

Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20220307213356.2797205-41-brijesh.singh@amd.com
2022-04-07 16:47:12 +02:00
Michael Roth 8c9c509baf x86/boot: Add a pointer to Confidential Computing blob in bootparams
The previously defined Confidential Computing blob is provided to the
kernel via a setup_data structure or EFI config table entry. Currently,
these are both checked for by boot/compressed kernel to access the CPUID
table address within it for use with SEV-SNP CPUID enforcement.

To also enable that enforcement for the run-time kernel, similar
access to the CPUID table is needed early on while it's still using
the identity-mapped page table set up by boot/compressed, where global
pointers need to be accessed via fixup_pointer().

This isn't much of an issue for accessing setup_data, and the EFI config
table helper code currently used in boot/compressed *could* be used in
this case as well since they both rely on identity-mapping. However, it
has some reliance on EFI helpers/string constants that would need to be
accessed via fixup_pointer(), and fixing it up while making it shareable
between boot/compressed and run-time kernel is fragile and introduces a
good bit of ugliness.

Instead, add a boot_params->cc_blob_address pointer that the
boot/compressed kernel can initialize so that the run-time kernel can
access the CC blob from there instead of re-scanning the EFI config
table.

Also document these in Documentation/x86/zero-page.rst. While there,
add missing documentation for the acpi_rsdp_addr field, which serves a
similar purpose in providing the run-time kernel a pointer to the ACPI
RSDP table so that it does not need to [re-]scan the EFI configuration
table.

  [ bp: Fix typos, massage commit message. ]

Signed-off-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20220307213356.2797205-34-brijesh.singh@amd.com
2022-04-07 16:47:11 +02:00
Chin En Lin d4cd2389d0 Documentation: x86: Fix obsolete name of page fault handler
Since commit 91eeafea1e ("x86/entry: Switch page fault exception to
IDTENTRY_RAW"), the function name of the page fault handler is out of date.
And because of commit aa37c51b94 ("x86/mm: Break out user address space
handling"), the description of search_exception_table is not correct
anymore. It may mislead the user who wants to use the documentation to
figure out the page fault handler.

Also, fix typo and add the parentheses after function and macro name.

Signed-off-by: Chin En Lin <shiyn.lin@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-04-05 10:28:36 -06:00
Borislav Petkov 76ea0025a2 x86/cpu: Remove "noexec"
It doesn't make any sense to disable non-executable mappings -
security-wise or else.

So rip out that switch and move the remaining code into setup.c and
delete setup_nx.c

Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220127115626.14179-6-bp@alien8.de
2022-04-04 10:17:03 +02:00
Borislav Petkov 385d2ae0a1 x86/cpu: Remove "nosmep"
There should be no need to disable SMEP anymore.

Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220127115626.14179-5-bp@alien8.de
2022-04-04 10:17:00 +02:00
Borislav Petkov dbae0a934f x86/cpu: Remove CONFIG_X86_SMAP and "nosmap"
Those were added as part of the SMAP enablement but SMAP is currently
an integral part of kernel proper and there's no need to disable it
anymore.

Rip out that functionality. Leave --uaccess default on for objtool as
this is what objtool should do by default anyway.

If still needed - clearcpuid=smap.

Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220127115626.14179-4-bp@alien8.de
2022-04-04 10:16:57 +02:00
Linus Torvalds 636f64db07 - More noinstr fixes
- Add an erratum workaround for Intel CPUs which, in certain
 circumstances, end up consuming an unrelated uncorrectable memory error
 when using fast string copy insns
 
 - Remove the MCE tolerance level control as it is not really needed or
 used anymore
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Merge tag 'ras_core_for_v5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RAS updates from Borislav Petkov:

 - More noinstr fixes

 - Add an erratum workaround for Intel CPUs which, in certain
   circumstances, end up consuming an unrelated uncorrectable memory
   error when using fast string copy insns

 - Remove the MCE tolerance level control as it is not really needed or
   used anymore

* tag 'ras_core_for_v5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Remove the tolerance level control
  x86/mce: Work around an erratum on fast string copy instructions
  x86/mce: Use arch atomic and bit helpers
2022-03-25 12:34:53 -07:00
Linus Torvalds 1464677662 platform-drivers-x86 for v5.18-1
Highlights:
 - 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
 
 The following is an automated git shortlog grouped by driver:
 
 ACPI / scan:
  -  Create platform device for CS35L41
 
 ACPI / x86:
  -  Add support for LPS0 callback handler
 
 ALSA:
  -  hda/realtek: Add support for HP Laptops
 
 Add AMD system management interface:
  - Add AMD system management interface
 
 Add Intel Software Defined Silicon driver:
  - Add Intel Software Defined Silicon driver
 
 Documentation:
  -  syfs-class-firmware-attributes: Lenovo Certificate support
  -  Add x86/amd_hsmp driver
 
 ISST:
  -  Fix possible circular locking dependency detected
 
 Input:
  -  soc_button_array - add support for Microsoft Surface 3 (MSHW0028) buttons
 
 Merge remote-tracking branch 'pdx86/platform-drivers-x86-pinctrl-pmu_clk' into review-hans-gcc12:
  - Merge remote-tracking branch 'pdx86/platform-drivers-x86-pinctrl-pmu_clk' into review-hans-gcc12
 
 Merge tag 'platform-drivers-x86-serial-multi-instantiate-1' into review-hans:
  - Merge tag 'platform-drivers-x86-serial-multi-instantiate-1' into review-hans
 
 Replace acpi_bus_get_device():
  - Replace acpi_bus_get_device()
 
 amd-pmc:
  -  Only report STB errors when STB enabled
  -  Drop CPU QoS workaround
  -  Output error codes in messages
  -  Move to later in the suspend process
  -  Validate entry into the deepest state on resume
  -  uninitialized variable in amd_pmc_s2d_init()
  -  Set QOS during suspend on CZN w/ timer wakeup
  -  Add support for AMD Spill to DRAM STB feature
  -  Correct usage of SMU version
  -  Make amd_pmc_stb_debugfs_fops static
 
 asus-tf103c-dock:
  -  Make 2 global structs static
 
 asus-wmi:
  -  Fix regression when probing for fan curve control
 
 hp-wmi:
  -  support omen thermal profile policy v1
  -  Changing bios_args.data to be dynamically allocated
  -  Fix 0x05 error code reported by several WMI calls
  -  Fix SW_TABLET_MODE detection method
  -  Fix hp_wmi_read_int() reporting error (0x05)
 
 huawei-wmi:
  -  check the return value of device_create_file()
 
 i2c-multi-instantiate:
  -  Rename it for a generic serial driver name
 
 int3472:
  -  Add terminator to gpiod_lookup_table
 
 intel-uncore-freq:
  -  fix uncore_freq_common_init() error codes
 
 intel_cht_int33fe:
  -  Move to intel directory
  -  Drop Lenovo Yogabook YB1-X9x code
  -  Switch to DMI modalias based loading
 
 intel_crystal_cove_charger:
  -  Fix IRQ masking / unmasking
 
 lg-laptop:
  -  Move setting of battery charge limit to common location
 
 pinctrl:
  -  baytrail: Add pinconf group + function for the pmu_clk
 
 platform/dcdbas:
  -  move EXPORT_SYMBOL after function
 
 platform/surface:
  -  Remove Surface 3 Button driver
  -  surface3-wmi: Simplify resource management
  -  Replace acpi_bus_get_device()
  -  Reinstate platform dependency
 
 platform/x86/intel-uncore-freq:
  -  Split common and enumeration part
 
 platform/x86/intel/uncore-freq:
  -  Display uncore current frequency
  -  Use sysfs API to create attributes
  -  Move to uncore-frequency folder
 
 selftests:
  -  sdsi: test sysfs setup
 
 serial-multi-instantiate:
  -  Add SPI support
  -  Reorganize I2C functions
 
 spi:
  -  Add API to count spi acpi resources
  -  Support selection of the index of the ACPI Spi Resource before alloc
  -  Create helper API to lookup ACPI info for spi device
  -  Make spi_alloc_device and spi_add_device public again
 
 surface:
  -  surface3_power: Fix battery readings on batteries without a serial number
 
 think-lmi:
  -  Certificate authentication support
 
 thinkpad_acpi:
  -  consistently check fan_get_status return.
  -  Don't use test_bit on an integer
  -  Fix compiler warning about uninitialized err variable
  -  clean up dytc profile convert
  -  Add PSC mode support
  -  Add dual fan probe
  -  Add dual-fan quirk for T15g (2nd gen)
  -  Fix incorrect use of platform profile on AMD platforms
  -  Add quirk for ThinkPads without a fan
 
 tools arch x86:
  -  Add Intel SDSi provisiong tool
 
 touchscreen_dmi:
  -  Add info for the RWC NANOTE P8 AY07J 2-in-1
 
 x86-android-tablets:
  -  Depend on EFI and SPI
  -  Lenovo Yoga Tablet 2 830/1050 sound support
  -  Workaround Lenovo Yoga Tablet 2 830/1050 poweroff hang
  -  Add Lenovo Yoga Tablet 2 830 / 1050 data
  -  Fix EBUSY error when requesting IOAPIC IRQs
  -  Minor charger / fuel-gauge improvements
  -  Add Nextbook Ares 8 data
  -  Add IRQ to Asus ME176C accelerometer info
  -  Add lid-switch gpio-keys pdev to Asus ME176C + TF103C
  -  Add x86_android_tablet_get_gpiod() helper
  -  Add Asus ME176C/TF103C charger and fuelgauge props
  -  Add battery swnode support
  -  Trivial typo fix for MODULE_AUTHOR
  -  Fix the buttons on CZC P10T tablet
  -  Constify the gpiod_lookup_tables arrays
  -  Add an init() callback to struct x86_dev_info
  -  Add support for disabling ACPI _AEI handlers
  -  Correct crystal_cove_charger module name
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Merge tag 'platform-drivers-x86-v5.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86

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
  ...
2022-03-25 12:14:39 -07:00
Linus Torvalds f648372dfe Thermal control updates for 5.18-rc1
- Add a new thermal driver for the Intel Hardware Feedback Interface
    (HFI) including the HFI initialization, HFI notification interrupt
    handling and sending CPU capabilities change messages to user
    space via the thermal netlink interface (Ricardo Neri, Srinivas
    Pandruvada, Nathan Chancellor, Randy Dunlap).
 
  - Extend the intel-speed-select utility to handle out-of-band CPU
    configuration changes and add support for the CPU capabilities
    change messages sent over the thermal netlink interface by the new
    HFI thermal driver to it (Srinivas Pandruvada).
 
  - Convert the DT bindings to yaml format for the Exynos platform
    and fix and update the MAINTAINERS file for this driver (Krzysztof
    Kozlowski).
 
  - Register the thermal zones as HWmon sensors for the QCom's
    Tsens driver and TI thermal platforms (Dmitry Baryshkov, Romain
    Naour).
 
  - Add the msm8953 compatible documentation in the bindings (Luca
    Weiss).
 
  - Add the sm8150 platform support to the QCom LMh driver's DT
    binding (Thara Gopinath).
 
  - Check the command result from the IPC command to the BPMP in the
    Tegra driver (Mikko Perttunen).
 
  - Silence the error for normal configuration where the interrupt
    is optionnal in the Broadcom thermal driver (Florian Fainelli).
 
  - Remove remaining dead code from the TI thermal driver (Yue
    Haibing).
 
  - Don't use bitmap_weight() in end_power_clamp() in the powerclamp
    driver (Yury Norov).
 
  - Update the OS policy capabilities handshake in the int340x thermal
    driver (Srinivas Pandruvada).
 
  - Increase the policies bitmap size in int340x (Srinivas Pandruvada).
 
  - Replace acpi_bus_get_device() with acpi_fetch_acpi_dev() in the
    int340x thermal driver (Rafael Wysocki).
 
  - Check for NULL after calling kmemdup() in int340x (Jiasheng Jiang).
 
  - Add Intel Dynamic Power and Thermal Framework (DPTF) kernel interface
    documentation (Srinivas Pandruvada).
 
  - Fix bullet list warning in the thermal documentation (Randy Dunlap).
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Merge tag 'thermal-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull thermal control updates from Rafael Wysocki:
 "As far as new functionality is concerned, there is a new thermal
  driver for the Intel Hardware Feedback Interface (HFI) along with some
  intel-speed-select utility changes to support it. There are also new
  DT compatible strings for a couple of platforms, and thermal zones on
  some platforms will be registered as HWmon sensors now.

  Apart from the above, some drivers are updated (fixes mostly) and
  there is a new piece of documentation for the Intel DPTF (Dynamic
  Power and Thermal Framework) sysfs interface.

  Specifics:

   - Add a new thermal driver for the Intel Hardware Feedback Interface
     (HFI) including the HFI initialization, HFI notification interrupt
     handling and sending CPU capabilities change messages to user space
     via the thermal netlink interface (Ricardo Neri, Srinivas
     Pandruvada, Nathan Chancellor, Randy Dunlap).

   - Extend the intel-speed-select utility to handle out-of-band CPU
     configuration changes and add support for the CPU capabilities
     change messages sent over the thermal netlink interface by the new
     HFI thermal driver to it (Srinivas Pandruvada).

   - Convert the DT bindings to yaml format for the Exynos platform and
     fix and update the MAINTAINERS file for this driver (Krzysztof
     Kozlowski).

   - Register the thermal zones as HWmon sensors for the QCom's Tsens
     driver and TI thermal platforms (Dmitry Baryshkov, Romain Naour).

   - Add the msm8953 compatible documentation in the bindings (Luca
     Weiss).

   - Add the sm8150 platform support to the QCom LMh driver's DT binding
     (Thara Gopinath).

   - Check the command result from the IPC command to the BPMP in the
     Tegra driver (Mikko Perttunen).

   - Silence the error for normal configuration where the interrupt is
     optionnal in the Broadcom thermal driver (Florian Fainelli).

   - Remove remaining dead code from the TI thermal driver (Yue
     Haibing).

   - Don't use bitmap_weight() in end_power_clamp() in the powerclamp
     driver (Yury Norov).

   - Update the OS policy capabilities handshake in the int340x thermal
     driver (Srinivas Pandruvada).

   - Increase the policies bitmap size in int340x (Srinivas Pandruvada).

   - Replace acpi_bus_get_device() with acpi_fetch_acpi_dev() in the
     int340x thermal driver (Rafael Wysocki).

   - Check for NULL after calling kmemdup() in int340x (Jiasheng Jiang).

   - Add Intel Dynamic Power and Thermal Framework (DPTF) kernel
     interface documentation (Srinivas Pandruvada).

   - Fix bullet list warning in the thermal documentation (Randy
     Dunlap)"

* tag 'thermal-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (30 commits)
  thermal: int340x: Update OS policy capability handshake
  thermal: int340x: Increase bitmap size
  Documentation: thermal: DPTF Documentation
  MAINTAINERS: thermal: samsung: update Krzysztof Kozlowski's email
  thermal/drivers/ti-soc-thermal: Remove unused function ti_thermal_get_temp()
  thermal/drivers/brcmstb_thermal: Interrupt is optional
  thermal: tegra-bpmp: Handle errors in BPMP response
  drivers/thermal/ti-soc-thermal: Add hwmon support
  dt-bindings: thermal: tsens: Add msm8953 compatible
  dt-bindings: thermal: Add sm8150 compatible string for LMh
  thermal/drivers/qcom/lmh: Add support for sm8150
  thermal/drivers/tsens: register thermal zones as hwmon sensors
  MAINTAINERS: thermal: samsung: Drop obsolete properties
  dt-bindings: thermal: samsung: Convert to dtschema
  tools/power/x86/intel-speed-select: v1.12 release
  tools/power/x86/intel-speed-select: HFI support
  tools/power/x86/intel-speed-select: OOB daemon mode
  thermal: intel: hfi: INTEL_HFI_THERMAL depends on NET
  thermal: netlink: Fix parameter type of thermal_genl_cpu_capability_event() stub
  thermal: Replace acpi_bus_get_device()
  ...
2022-03-21 14:35:11 -07:00
Naveen Krishna Chatradhi 402576d980 Documentation: Add x86/amd_hsmp driver
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>
2022-03-02 11:42:36 +01:00
Borislav Petkov 7f1b8e0d63 x86/mce: Remove the tolerance level control
This is pretty much unused and not really useful. What is more, all
relevant MCA hardware has recoverable machine checks support so there's
no real need to tweak MCA tolerance levels in order to *maybe* extend
machine lifetime.

So rip it out.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/YcDq8PxvKtTENl/e@zn.tnic
2022-02-23 11:09:25 +01:00
Fenghua Yu 83aa52ffed Documentation/x86: Update documentation for SVA (Shared Virtual Addressing)
Adjust the documentation to the new way how a PASID is being allocated,
freed and fixed up.

Based on a patch by Ashok Raj <ashok.raj@intel.com>

  [ bp: Massage commit message, fix htmldocs build warning ]

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>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20220207230254.3342514-12-fenghua.yu@intel.com
2022-02-15 11:31:43 +01:00
Ricardo Neri 4a960e8941 x86/Documentation: Describe the Intel Hardware Feedback Interface
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>
2022-02-03 19:50:48 +01:00
Reinette Chatre 379e4de9e1 x86/sgx: Fix minor documentation issues
The SGX documentation has a few repeated or one-off issues:

 * Remove capitalization from regular words in the middle of a sentence.
 * Remove punctuation found in the middle of a sentence.
 * Fix name of SGX daemon to consistently be ksgxd.
 * Fix typo of SGX instruction: ENIT -> EINIT

[ dhansen: tweaked subject and changelog ]

Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Link: https://lkml.kernel.org/r/ab99a87368eef69e3fb96f073368becff3eff874.1635529506.git.reinette.chatre@intel.com
2021-11-17 06:36:09 -08:00
Linus Torvalds 1654e95ee3 - Add the model number of a new, Raptor Lake CPU, to intel-family.h
- Do not log spurious corrected MCEs on SKL too, due to an erratum
 
 - Clarify the path of paravirt ops patches upstream
 
 - Add an optimization to avoid writing out AMX components to sigframes
 when former are in init state
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Merge tag 'x86_urgent_for_v5.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Borislav Petkov:

 - Add the model number of a new, Raptor Lake CPU, to intel-family.h

 - Do not log spurious corrected MCEs on SKL too, due to an erratum

 - Clarify the path of paravirt ops patches upstream

 - Add an optimization to avoid writing out AMX components to sigframes
   when former are in init state

* tag 'x86_urgent_for_v5.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/cpu: Add Raptor Lake to Intel family
  x86/mce: Add errata workaround for Skylake SKX37
  MAINTAINERS: Add some information to PARAVIRT_OPS entry
  x86/fpu: Optimize out sigframe xfeatures when in init state
2021-11-14 09:29:03 -08:00
Linus Torvalds 95faf6ba65 Driver core changes for 5.16-rc1
Here is the big set of driver core changes for 5.16-rc1.
 
 All of these have been in linux-next for a while now with no reported
 problems.
 
 Included in here are:
 	- big update and cleanup of the sysfs abi documentation files
 	  and scripts from Mauro.  We are almost at the place where we
 	  can properly check that the running kernel's sysfs abi is
 	  documented fully.
 	- firmware loader updates
 	- dyndbg updates
 	- kernfs cleanups and fixes from Christoph
 	- device property updates
 	- component fix
 	- other minor driver core cleanups and fixes
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the big set of driver core changes for 5.16-rc1.

  All of these have been in linux-next for a while now with no reported
  problems.

  Included in here are:

   - big update and cleanup of the sysfs abi documentation files and
     scripts from Mauro. We are almost at the place where we can
     properly check that the running kernel's sysfs abi is documented
     fully.

   - firmware loader updates

   - dyndbg updates

   - kernfs cleanups and fixes from Christoph

   - device property updates

   - component fix

   - other minor driver core cleanups and fixes"

* tag 'driver-core-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (122 commits)
  device property: Drop redundant NULL checks
  x86/build: Tuck away built-in firmware under FW_LOADER
  vmlinux.lds.h: wrap built-in firmware support under FW_LOADER
  firmware_loader: move struct builtin_fw to the only place used
  x86/microcode: Use the firmware_loader built-in API
  firmware_loader: remove old DECLARE_BUILTIN_FIRMWARE()
  firmware_loader: formalize built-in firmware API
  component: do not leave master devres group open after bind
  dyndbg: refine verbosity 1-4 summary-detail
  gpiolib: acpi: Replace custom code with device_match_acpi_handle()
  i2c: acpi: Replace custom function with device_match_acpi_handle()
  driver core: Provide device_match_acpi_handle() helper
  dyndbg: fix spurious vNpr_info change
  dyndbg: no vpr-info on empty queries
  dyndbg: vpr-info on remove-module complete, not starting
  device property: Add missed header in fwnode.h
  Documentation: dyndbg: Improve cli param examples
  dyndbg: Remove support for ddebug_query param
  dyndbg: make dyndbg a known cli param
  dyndbg: show module in vpr-info in dd-exec-queries
  ...
2021-11-04 08:32:38 -07:00
Dave Hansen 30d02551ba x86/fpu: Optimize out sigframe xfeatures when in init state
tl;dr: AMX state is ~8k.  Signal frames can have space for this
~8k and each signal entry writes out all 8k even if it is zeros.
Skip writing zeros for AMX to speed up signal delivery by about
4% overall when AMX is in its init state.

This is a user-visible change to the sigframe ABI.

== Hardware XSAVE Background ==

XSAVE state components may be tracked by the processor as being
in their initial configuration.  Software can detect which
features are in this configuration by looking at the XSTATE_BV
field in an XSAVE buffer or with the XGETBV(1) instruction.

Both the XSAVE and XSAVEOPT instructions enumerate features s
being in the initial configuration via the XSTATE_BV field in the
XSAVE header,  However, XSAVEOPT declines to actually write
features in their initial configuration to the buffer.  XSAVE
writes the feature unconditionally, regardless of whether it is
in the initial configuration or not.

Basically, XSAVE users never need to inspect XSTATE_BV to
determine if the feature has been written to the buffer.
XSAVEOPT users *do* need to inspect XSTATE_BV.  They might also
need to clear out the buffer if they want to make an isolated
change to the state, like modifying one register.

== Software Signal / XSAVE Background ==

Signal frames have historically been written with XSAVE itself.
Each state is written in its entirety, regardless of being in its
initial configuration.

In other words, the signal frame ABI uses the XSAVE behavior, not
the XSAVEOPT behavior.

== Problem ==

This means that any application which has acquired permission to
use AMX via ARCH_REQ_XCOMP_PERM will write 8k of state to the
signal frame.  This 8k write will occur even when AMX was in its
initial configuration and software *knows* this because of
XSTATE_BV.

This problem also exists to a lesser degree with AVX-512 and its
2k of state.  However, AVX-512 use does not require
ARCH_REQ_XCOMP_PERM and is more likely to have existing users
which would be impacted by any change in behavior.

== Solution ==

Stop writing out AMX xfeatures which are in their initial state
to the signal frame.  This effectively makes the signal frame
XSAVE buffer look as if it were written with a combination of
XSAVEOPT and XSAVE behavior.  Userspace which handles XSAVEOPT-
style buffers should be able to handle this naturally.

For now, include only the AMX xfeatures: XTILE and XTILEDATA in
this new behavior.  These require new ABI to use anyway, which
makes their users very unlikely to be broken.  This XSAVEOPT-like
behavior should be expected for all future dynamic xfeatures.  It
may also be extended to legacy features like AVX-512 in the
future.

Only attempt this optimization on systems with dynamic features.
Disable dynamic feature support (XFD) if XGETBV1 is unavailable
by adding a CPUID dependency.

This has been measured to reduce the *overall* cycle cost of
signal delivery by about 4%.

Fixes: 2308ee57d9 ("x86/fpu/amx: Enable the AMX feature in 64-bit mode")
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: "Chang S. Bae" <chang.seok.bae@intel.com>
Link: https://lore.kernel.org/r/20211102224750.FA412E26@davehans-spike.ostc.intel.com
2021-11-03 22:42:35 +01:00
Linus Torvalds 624ad333d4 This is a relatively unexciting cycle for documentation.
- Some small scripts/kerneldoc fixes
 
  - More Chinese translation work, but at a much reduced rate.
 
  - The tip-tree maintainer's handbook
 
 ...plus the usual array of build fixes, typo fixes, etc.
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Merge tag 'docs-5.16' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "This is a relatively unexciting cycle for documentation.

   - Some small scripts/kerneldoc fixes

   - More Chinese translation work, but at a much reduced rate.

   - The tip-tree maintainer's handbook

  ...plus the usual array of build fixes, typo fixes, etc"

* tag 'docs-5.16' of git://git.lwn.net/linux: (53 commits)
  kernel-doc: support DECLARE_PHY_INTERFACE_MASK()
  docs/zh_CN: add core-api xarray translation
  docs/zh_CN: add core-api assoc_array translation
  speakup: Fix typo in documentation "boo" -> "boot"
  docs: submitting-patches: make section about the Link: tag more explicit
  docs: deprecated.rst: Clarify open-coded arithmetic with literals
  scripts: documentation-file-ref-check: fix bpf selftests path
  scripts: documentation-file-ref-check: ignore hidden files
  coding-style.rst: trivial: fix location of driver model macros
  docs: f2fs: fix text alignment
  docs/zh_CN add PCI pci.rst translation
  docs/zh_CN add PCI index.rst translation
  docs: translations: zh_CN: memory-hotplug.rst: fix a typo
  docs: translations: zn_CN: irq-affinity.rst: add a missing extension
  block: add documentation for inflight
  scripts: kernel-doc: Ignore __alloc_size() attribute
  docs: pdfdocs: Adjust \headheight for fancyhdr
  docs: UML: user_mode_linux_howto_v2 edits
  docs: use the lore redirector everywhere
  docs: proc.rst: mountinfo: align columns
  ...
2021-11-02 22:11:39 -07:00
Linus Torvalds 879dbe9ffe Add a SGX_IOC_VEPC_REMOVE ioctl to the /dev/sgx_vepc virt interface with
which EPC pages can be put back into their uninitialized state without
 having to reopen /dev/sgx_vepc, which could not be possible anymore
 after startup due to security policies.
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Merge tag 'x86_sgx_for_v5.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 SGX updates from Borislav Petkov:
 "Add a SGX_IOC_VEPC_REMOVE ioctl to the /dev/sgx_vepc virt interface
  with which EPC pages can be put back into their uninitialized state
  without having to reopen /dev/sgx_vepc, which could not be possible
  anymore after startup due to security policies"

* tag 'x86_sgx_for_v5.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/sgx/virt: implement SGX_IOC_VEPC_REMOVE ioctl
  x86/sgx/virt: extract sgx_vepc_remove_page
2021-11-01 15:54:07 -07:00
Chang S. Bae d7a9590f60 Documentation/x86: Add documentation for using dynamic XSTATE features
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
2021-10-28 14:54:58 +02:00
Paolo Bonzini ae095b16fc x86/sgx/virt: implement SGX_IOC_VEPC_REMOVE ioctl
For bare-metal SGX on real hardware, the hardware provides guarantees
SGX state at reboot.  For instance, all pages start out uninitialized.
The vepc driver provides a similar guarantee today for freshly-opened
vepc instances, but guests such as Windows expect all pages to be in
uninitialized state on startup, including after every guest reboot.

Some userspace implementations of virtual SGX would rather avoid having
to close and reopen the /dev/sgx_vepc file descriptor and re-mmap the
virtual EPC.  For example, they could sandbox themselves after the guest
starts and forbid further calls to open(), in order to mitigate exploits
from untrusted guests.

Therefore, add a ioctl that does this with EREMOVE.  Userspace can
invoke the ioctl to bring its vEPC pages back to uninitialized state.
There is a possibility that some pages fail to be removed if they are
SECS pages, and the child and SECS pages could be in separate vEPC
regions.  Therefore, the ioctl returns the number of EREMOVE failures,
telling userspace to try the ioctl again after it's done with all
vEPC regions.  A more verbose description of the correct usage and
the possible error conditions is documented in sgx.rst.

Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lkml.kernel.org/r/20211021201155.1523989-3-pbonzini@redhat.com
2021-10-22 08:32:12 -07:00
Thorsten Leemhuis a9d85efb25 docs: use the lore redirector everywhere
Change all links from using the lkml redirector to the lore redirector,
as the kernel.org admin recently indicated: we shouldn't be using
lkml.kernel.org anymore because the domain can create confusion, as it
indicates it is only valid for messages sent to the LKML; the convention
has been to use https://lore.kernel.org/r/msgid for this reason.

In this process also change three links from using http to https.

Link: https://lore.kernel.org/r/20211006170025.qw3glxvocczfuhar@meerkat.local
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Ingo Molnar <mingo@redhat.com>
CC: Borislav Petkov <bp@alien8.de>
CC: Hu Haowen <src.res@email.cn>
CC: Alex Shi <alexs@kernel.org>
CC: Federico Vaga <federico.vaga@vaga.pv.it>
Signed-off-by: Thorsten Leemhuis <linux@leemhuis.info>
Reviewed-by: Konstantin Ryabitsev <konstantin@linuxfoundation.org>
Link: https://lore.kernel.org/r/5bb55bac6ba10fafab19bf2b21572dd0e2f8cea2.1633593385.git.linux@leemhuis.info
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-10-12 13:58:19 -06:00
Mauro Carvalho Chehab edfc8730ba ABI: sysfs-mce: add a new ABI file
Reduce the gap of missing ABIs for Intel servers with MCE
by adding a new ABI file.

The contents of this file comes from:
	Documentation/x86/x86_64/machinecheck.rst

Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/801a26985e32589eb78ba4b728d3e19fdea18f04.1632994837.git.mchehab+huawei@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-05 16:24:15 +02:00
Linus Torvalds 0f4b9289ba Another collection of documentation patches, mostly fixes but also includes
another set of traditional Chinese translations.
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Merge tag 'docs-5.15-2' of git://git.lwn.net/linux

Pull more documentation updates from Jonathan Corbet:
 "Another collection of documentation patches, mostly fixes but also
  includes another set of traditional Chinese translations"

* tag 'docs-5.15-2' of git://git.lwn.net/linux:
  docs: pdfdocs: Fix typo in CJK-language specific font settings
  docs: kernel-hacking: Remove inappropriate text
  docs/zh_TW: add translations for zh_TW/filesystems
  docs/zh_TW: add translations for zh_TW/cpu-freq
  docs/zh_TW: add translations for zh_TW/arm64
  docs/zh_CN: Modify the translator tag and fix the wrong word
  Documentation/features/vm: correct huge-vmap APIs
  Documentation: block: blk-mq: Fix small typo in multi-queue docs
  Documentation: in_irq() cleanup
  Documentation: arm: marvell: Add 88F6825 model into list
  Documentation/process/maintainer-pgp-guide: Replace broken link to PGP path finder
  Documentation: locking: fix references
  Documentation: Update details of The Linux Kernel Module Programming Guide
  docs: x86: Remove obsolete information about x86_64 vmalloc() faulting
  Documentation/process/applying-patches: Activate linux-next man hyperlink
2021-09-08 16:28:14 -07:00
Peilin Ye 251a7b3edc docs: x86: Remove obsolete information about x86_64 vmalloc() faulting
x86_64 vmalloc() mappings are no longer "synchronized" among page tables
via faulting since commit 6eb82f9940 ("x86/mm: Pre-allocate P4D/PUD
pages for vmalloc area"), since the corresponding P4D or PUD pages are
now preallocated at boot, by preallocate_vmalloc_pages().  Drop the
"lazily synchronized" description for less confusion.

While this file is x86_64-specific, it is worth noting that things are
different for x86_32, where vmalloc()-related changes to `init_mm.pgd` are
synchronized to all page tables in the system during runtime, via
arch_sync_kernel_mappings().  Unfortunately, this synchronization is
subject to race condition, which is further handled via faulting, see
vmalloc_fault().  See commit 4819e15f74 ("x86/mm/32: Bring back vmalloc
faulting on x86_32") for more details.

Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Link: https://lore.kernel.org/r/20210818220123.2623-1-yepeilin.cs@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-08-20 11:14:11 -06:00
Paul Gortmaker 12febc1818 x86/reboot: Document how to override DMI platform quirks
commit 5955633e91 ("x86/reboot: Skip DMI checks if reboot set by user")
made it so that it's not required to recompile the kernel in order to
bypass broken reboot quirks compiled into an image:

 * This variable is used privately to keep track of whether or not
 * reboot_type is still set to its default value (i.e., reboot= hasn't
 * been set on the command line).  This is needed so that we can
 * suppress DMI scanning for reboot quirks.  Without it, it's
 * impossible to override a faulty reboot quirk without recompiling.

However, at the time it was not eally documented outside the source code,
and so this information isn't really available to the average user out
there.

The change is a little white lie and invented "reboot=default" since it is
easy to remember, and documents well.  The truth is that any random string
that is *not* a currently accepted string will work.

Since that doesn't document well for non-coders, and since it's unknown
what the future additions might be, lay claim on "default" since that is
exactly what it achieves.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210530162447.996461-3-paul.gortmaker@windriver.com
2021-08-12 12:06:58 +02:00
Paul Gortmaker 162a5284fa x86/reboot: Document the "reboot=pci" option
It is mentioned in the top level non-arch specific file but it was
overlooked here for x86.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210530162447.996461-2-paul.gortmaker@windriver.com
2021-08-12 12:06:58 +02:00
Linus Torvalds 1423e2660c 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.
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Merge tag 'x86-fpu-2021-07-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

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()
  ...
2021-07-07 11:12:01 -07:00
Linus Torvalds 233a806b00 This was a reasonably active cycle for documentation; this pull includes:
- Some kernel-doc cleanups.  That script is still regex onslaught from
    hell, but it has gotten a little better.
 
  - Improvements to the checkpatch docs, which are also used by the tool
    itself.
 
  - A major update to the pathname lookup documentation.
 
  - Elimination of :doc: markup, since our automarkup magic can create
    references from filenames without all the extra noise.
 
  - The flurry of Chinese translation activity continues.
 
 Plus, of course, the usual collection of updates, typo fixes, and warning
 fixes.
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Merge tag 'docs-5.14' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "This was a reasonably active cycle for documentation; this includes:

   - Some kernel-doc cleanups. That script is still regex onslaught from
     hell, but it has gotten a little better.

   - Improvements to the checkpatch docs, which are also used by the
     tool itself.

   - A major update to the pathname lookup documentation.

   - Elimination of :doc: markup, since our automarkup magic can create
     references from filenames without all the extra noise.

   - The flurry of Chinese translation activity continues.

  Plus, of course, the usual collection of updates, typo fixes, and
  warning fixes"

* tag 'docs-5.14' of git://git.lwn.net/linux: (115 commits)
  docs: path-lookup: use bare function() rather than literals
  docs: path-lookup: update symlink description
  docs: path-lookup: update get_link() ->follow_link description
  docs: path-lookup: update WALK_GET, WALK_PUT desc
  docs: path-lookup: no get_link()
  docs: path-lookup: update i_op->put_link and cookie description
  docs: path-lookup: i_op->follow_link replaced with i_op->get_link
  docs: path-lookup: Add macro name to symlink limit description
  docs: path-lookup: remove filename_mountpoint
  docs: path-lookup: update do_last() part
  docs: path-lookup: update path_mountpoint() part
  docs: path-lookup: update path_to_nameidata() part
  docs: path-lookup: update follow_managed() part
  docs: Makefile: Use CONFIG_SHELL not SHELL
  docs: Take a little noise out of the build process
  docs: x86: avoid using ReST :doc:`foo` markup
  docs: virt: kvm: s390-pv-boot.rst: avoid using ReST :doc:`foo` markup
  docs: userspace-api: landlock.rst: avoid using ReST :doc:`foo` markup
  docs: trace: ftrace.rst: avoid using ReST :doc:`foo` markup
  docs: trace: coresight: coresight.rst: avoid using ReST :doc:`foo` markup
  ...
2021-06-28 16:53:05 -07:00
Linus Torvalds 1b1cf8fe99 Changes in this cycle were:
- Add the "ratelimit:N" parameter to the split_lock_detect= boot option,
    to rate-limit the generation of bus-lock exceptions. This is both
    easier on system resources and kinder to offending applications than
    the current policy of outright killing them.
 
  - Document the split-lock detection feature and its parameters.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'x86-splitlock-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 splitlock updates from Ingo Molnar:

 - Add the "ratelimit:N" parameter to the split_lock_detect= boot
   option, to rate-limit the generation of bus-lock exceptions.

   This is both easier on system resources and kinder to offending
   applications than the current policy of outright killing them.

 - Document the split-lock detection feature and its parameters.

* tag 'x86-splitlock-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Documentation/x86: Add ratelimit in buslock.rst
  Documentation/admin-guide: Add bus lock ratelimit
  x86/bus_lock: Set rate limit for bus lock
  Documentation/x86: Add buslock.rst
2021-06-28 13:30:02 -07:00
Mauro Carvalho Chehab 0ffd643875 docs: x86: avoid using ReST :doc:`foo` markup
The :doc:`foo` tag is auto-generated via automarkup.py.
So, use the filename at the sources, instead of :doc:`foo`.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/17c68b5f1d72488431c77c1de9f13683fe9f536c.1623824363.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-06-17 13:24:39 -06:00
Hubert Jasudowicz 0e5a89dbb4 doc: Remove references to IBM Calgary
The Calgary IOMMU driver has been removed in

  90dc392fc4 ("x86: Remove the calgary IOMMU driver")

Clean up stale docs that refer to it.

Signed-off-by: Hubert Jasudowicz <hubert.jasudowicz@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/1bd2b57dd1db53df09e520b8170ff61418805de4.1623274832.git.hubert.jasudowicz@gmail.com
2021-06-10 18:19:36 +02:00
Chang S. Bae 1c33bb0507 x86/elf: Support a new ELF aux vector AT_MINSIGSTKSZ
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

  94b07c1f8c ("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
2021-05-19 12:18:45 +02:00
Fenghua Yu d28397eaf4 Documentation/x86: Add ratelimit in buslock.rst
ratelimit is a new command line option for bus lock handling. Add proper
documentation.

[ tglx: Massaged documentation ]

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/20210419214958.4035512-5-fenghua.yu@intel.com
2021-05-18 16:39:31 +02:00
Fenghua Yu 1897907cca Documentation/x86: Add buslock.rst
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
2021-05-18 16:39:31 +02:00
Brijesh Singh 059e5c321a x86/msr: Rename MSR_K8_SYSCFG to MSR_AMD64_SYSCFG
The SYSCFG MSR continued being updated beyond the K8 family; drop the K8
name from it.

Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Joerg Roedel <jroedel@suse.de>
Link: https://lkml.kernel.org/r/20210427111636.1207-4-brijesh.singh@amd.com
2021-05-10 07:51:38 +02:00
Linus Torvalds a3f53e8adf A few late-arriving documentation fixes, including some oprofile cleanup, a
kernel-doc fix, some regression-reporting updates, and the usual minor
 fixes.
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Merge tag 'docs-5.13-2' of git://git.lwn.net/linux

Pull documentation fixes from Jonathan Corbet:
 "A few late-arriving documentation fixes, including some oprofile
  cleanup, a kernel-doc fix, some regression-reporting updates, and the
  usual minor fixes"

* tag 'docs-5.13-2' of git://git.lwn.net/linux:
  Enlisted oprofile version line removed
  oprofiled version output line removed from the list
  Removed the oprofiled version option
  docs: reporting-issues.rst: CC subsystem and maintainers on regressions
  docs: correct URL to bios and kernel developer's guide
  docs/core-api: Consistent code style
  docs/zh_CN: Adjust order and content of zh_CN/index.rst
  Documentation: input: joydev file corrections
  docs: Fix typo in Documentation/x86/x86_64/5level-paging.rst
  kernel-doc: Add support for __deprecated
2021-05-06 08:33:54 -07:00
bilbao@vt.edu 6a79162fe5 docs: Fix typo in Documentation/x86/x86_64/5level-paging.rst
fix two typos in the documentation
(Documentation/x86/x86_64/5level-paging.rst), changing 'paing' for 'paging'
and using the right verbal form for plural on 'some vendors offer'.

Signed-off-by: Carlos Bilbao <bilbao@vt.edu>
Link: https://lore.kernel.org/r/2599991.mvXUDI8C0e@iron-maiden
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-04-27 13:03:30 -06:00
Sean Christopherson 540745ddbc x86/sgx: Introduce virtual EPC for use by KVM guests
Add a misc device /dev/sgx_vepc to allow userspace to allocate "raw"
Enclave Page Cache (EPC) without an associated enclave. The intended
and only known use case for raw EPC allocation is to expose EPC to a
KVM guest, hence the 'vepc' moniker, virt.{c,h} files and X86_SGX_KVM
Kconfig.

The SGX driver uses the misc device /dev/sgx_enclave to support
userspace in creating an enclave. Each file descriptor returned from
opening /dev/sgx_enclave represents an enclave. Unlike the SGX driver,
KVM doesn't control how the guest uses the EPC, therefore EPC allocated
to a KVM guest is not associated with an enclave, and /dev/sgx_enclave
is not suitable for allocating EPC for a KVM guest.

Having separate device nodes for the SGX driver and KVM virtual EPC also
allows separate permission control for running host SGX enclaves and KVM
SGX guests.

To use /dev/sgx_vepc to allocate a virtual EPC instance with particular
size, the hypervisor opens /dev/sgx_vepc, and uses mmap() with the
intended size to get an address range of virtual EPC. Then it may use
the address range to create one KVM memory slot as virtual EPC for
a guest.

Implement the "raw" EPC allocation in the x86 core-SGX subsystem via
/dev/sgx_vepc rather than in KVM. Doing so has two major advantages:

  - Does not require changes to KVM's uAPI, e.g. EPC gets handled as
    just another memory backend for guests.

  - EPC management is wholly contained in the SGX subsystem, e.g. SGX
    does not have to export any symbols, changes to reclaim flows don't
    need to be routed through KVM, SGX's dirty laundry doesn't have to
    get aired out for the world to see, and so on and so forth.

The virtual EPC pages allocated to guests are currently not reclaimable.
Reclaiming an EPC page used by enclave requires a special reclaim
mechanism separate from normal page reclaim, and that mechanism is not
supported for virutal EPC pages. Due to the complications of handling
reclaim conflicts between guest and host, reclaiming virtual EPC pages
is significantly more complex than basic support for SGX virtualization.

 [ bp:
   - Massage commit message and comments
   - use cpu_feature_enabled()
   - vertically align struct members init
   - massage Virtual EPC clarification text
   - move Kconfig prompt to Virtualization ]

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Co-developed-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Link: https://lkml.kernel.org/r/0c38ced8c8e5a69872db4d6a1c0dabd01e07cad7.1616136308.git.kai.huang@intel.com
2021-04-06 09:43:17 +02:00
Kai Huang b0c7459be0 x86/sgx: Wipe out EREMOVE from sgx_free_epc_page()
EREMOVE takes a page and removes any association between that page and
an enclave. It must be run on a page before it can be added into another
enclave. Currently, EREMOVE is run as part of pages being freed into the
SGX page allocator. It is not expected to fail, as it would indicate a
use-after-free of EPC pages. Rather than add the page back to the pool
of available EPC pages, the kernel intentionally leaks the page to avoid
additional errors in the future.

However, KVM does not track how guest pages are used, which means that
SGX virtualization use of EREMOVE might fail. Specifically, it is
legitimate that EREMOVE returns SGX_CHILD_PRESENT for EPC assigned to
KVM guest, because KVM/kernel doesn't track SECS pages.

To allow SGX/KVM to introduce a more permissive EREMOVE helper and
to let the SGX virtualization code use the allocator directly, break
out the EREMOVE call from the SGX page allocator. Rename the original
sgx_free_epc_page() to sgx_encl_free_epc_page(), indicating that
it is used to free an EPC page assigned to a host enclave. Replace
sgx_free_epc_page() with sgx_encl_free_epc_page() in all call sites so
there's no functional change.

At the same time, improve the error message when EREMOVE fails, and
add documentation to explain to the user what that failure means and
to suggest to the user what to do when this bug happens in the case it
happens.

 [ bp: Massage commit message, fix typos and sanitize text, simplify. ]

Signed-off-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Link: https://lkml.kernel.org/r/20210325093057.122834-1-kai.huang@intel.com
2021-03-26 22:51:23 +01:00
Cao jin bcadb65fd6 Documentation/x86/boot.rst: Correct the example of SETUP_INDIRECT
struct setup_data.len is the length of data field. In case of
SETUP_INDIRECT, it should be sizeof(setup_indirect).

Signed-off-by: Cao jin <jojing64@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Link: https://lore.kernel.org/r/20210127084911.63438-1-jojing64@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-01-28 15:25:31 -07:00
Linus Torvalds ff6135959a 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.
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Merge tag 'docs-5.11' of git://git.lwn.net/linux

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
  ...
2020-12-14 16:55:54 -08:00