88 Commits

Author SHA1 Message Date
Ard Biesheuvel
944834901a Documentation: Drop or replace remaining mentions of IA64
Drop or update mentions of IA64, as appropriate.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2023-09-11 08:13:18 +00:00
Linus Torvalds
d68b4b6f30 - An extensive rework of kexec and crash Kconfig from Eric DeVolder
("refactor Kconfig to consolidate KEXEC and CRASH options").
 
 - kernel.h slimming work from Andy Shevchenko ("kernel.h: Split out a
   couple of macros to args.h").
 
 - gdb feature work from Kuan-Ying Lee ("Add GDB memory helper
   commands").
 
 - vsprintf inclusion rationalization from Andy Shevchenko
   ("lib/vsprintf: Rework header inclusions").
 
 - Switch the handling of kdump from a udev scheme to in-kernel handling,
   by Eric DeVolder ("crash: Kernel handling of CPU and memory hot
   un/plug").
 
 - Many singleton patches to various parts of the tree
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCZO2GpAAKCRDdBJ7gKXxA
 juW3AQD1moHzlSN6x9I3tjm5TWWNYFoFL8af7wXDJspp/DWH/AD/TO0XlWWhhbYy
 QHy7lL0Syha38kKLMXTM+bN6YQHi9AU=
 =WJQa
 -----END PGP SIGNATURE-----

Merge tag 'mm-nonmm-stable-2023-08-28-22-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:

 - An extensive rework of kexec and crash Kconfig from Eric DeVolder
   ("refactor Kconfig to consolidate KEXEC and CRASH options")

 - kernel.h slimming work from Andy Shevchenko ("kernel.h: Split out a
   couple of macros to args.h")

 - gdb feature work from Kuan-Ying Lee ("Add GDB memory helper
   commands")

 - vsprintf inclusion rationalization from Andy Shevchenko
   ("lib/vsprintf: Rework header inclusions")

 - Switch the handling of kdump from a udev scheme to in-kernel
   handling, by Eric DeVolder ("crash: Kernel handling of CPU and memory
   hot un/plug")

 - Many singleton patches to various parts of the tree

* tag 'mm-nonmm-stable-2023-08-28-22-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (81 commits)
  document while_each_thread(), change first_tid() to use for_each_thread()
  drivers/char/mem.c: shrink character device's devlist[] array
  x86/crash: optimize CPU changes
  crash: change crash_prepare_elf64_headers() to for_each_possible_cpu()
  crash: hotplug support for kexec_load()
  x86/crash: add x86 crash hotplug support
  crash: memory and CPU hotplug sysfs attributes
  kexec: exclude elfcorehdr from the segment digest
  crash: add generic infrastructure for crash hotplug support
  crash: move a few code bits to setup support of crash hotplug
  kstrtox: consistently use _tolower()
  kill do_each_thread()
  nilfs2: fix WARNING in mark_buffer_dirty due to discarded buffer reuse
  scripts/bloat-o-meter: count weak symbol sizes
  treewide: drop CONFIG_EMBEDDED
  lockdep: fix static memory detection even more
  lib/vsprintf: declare no_hash_pointers in sprintf.h
  lib/vsprintf: split out sprintf() and friends
  kernel/fork: stop playing lockless games for exe_file replacement
  adfs: delete unused "union adfs_dirtail" definition
  ...
2023-08-29 14:53:51 -07:00
Linus Torvalds
6f49693a6c Updates for the CPU hotplug core:
- Support partial SMT enablement.
 
     So far the sysfs SMT control only allows to toggle between SMT on and
     off. That's sufficient for x86 which usually has at max two threads
     except for the Xeon PHI platform which has four threads per core.
 
     Though PowerPC has up to 16 threads per core and so far it's only
     possible to control the number of enabled threads per core via a
     command line option. There is some way to control this at runtime, but
     that lacks enforcement and the usability is awkward.
 
     This update expands the sysfs interface and the core infrastructure to
     accept numerical values so PowerPC can build SMT runtime control for
     partial SMT enablement on top.
 
     The core support has also been provided to the PowerPC maintainers who
     added the PowerPC related changes on top.
 
   - Minor cleanups and documentation updates.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmTsj4wTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoaszEADKMd/6m7/Bq7RU2OJ+IXw8yfMEF9nS
 6HPrFu71a4cDufb/G8UckQOvkwdTFWD7bZ0snJe2sBDFTOtzK/inYkgPZTxlm7si
 JcJmFnHKUM7OTwNZb7Tv1bd9Csz4JhggAYUw6P8CqsCmhQ+p6ECemx3bHDlYiywm
 5eW2yzI9EM4dbsHPwUOvjI0WazGvAf0esSDAS8JTnhBXbd8FAckbMV+xuRPcCUK+
 dBqbqr+3Nf4/wcXTro/gZIc7sEATAHH6m7zHlLVBSyVPnBxre8NLz6KciW4SezyJ
 GWFnDV03mmG2KxQ2ugwI8n6M3zDJQtfEJFwW/x4t2M5RK+ka2a6G6GtCLHYOXLWR
 akIuBXtTAC57BgpqzBihGej9eiC1BJ1QMa9ZK+6WDXSZtMTFOLlbwdY2/qyfxpfw
 LfepWb+UMtFy5YyW84S1O5/AqpOtKD2kPTqfDjvDxWIAigispU+qwAKxcMzMjtwz
 aAlf2Z/iX0R9DkRzGD2gaFG5AUsRich8RtVO7u+WDwYSsi8ywrvryiPlZrDDBkSQ
 sRzdoHeXNGVY/FgkbZmEyBj4udrypymkR6ivqn6C2OrysgznSiv5NC983uS6TfJX
 cVqdUv6CNYYNiNu0x0Qf0MluYT2s5c1Fa4bjCBJL+KwORwjM3+TCN9RA1KtFrW2T
 G3Ta1KqI6wRonA==
 =JQRJ
 -----END PGP SIGNATURE-----

Merge tag 'smp-core-2023-08-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull CPU hotplug updates from Thomas Gleixner:
 "Updates for the CPU hotplug core:

   - Support partial SMT enablement.

     So far the sysfs SMT control only allows to toggle between SMT on
     and off. That's sufficient for x86 which usually has at max two
     threads except for the Xeon PHI platform which has four threads per
     core

     Though PowerPC has up to 16 threads per core and so far it's only
     possible to control the number of enabled threads per core via a
     command line option. There is some way to control this at runtime,
     but that lacks enforcement and the usability is awkward

     This update expands the sysfs interface and the core infrastructure
     to accept numerical values so PowerPC can build SMT runtime control
     for partial SMT enablement on top

     The core support has also been provided to the PowerPC maintainers
     who added the PowerPC related changes on top

   - Minor cleanups and documentation updates"

* tag 'smp-core-2023-08-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Documentation: core-api/cpuhotplug: Fix state names
  cpu/hotplug: Remove unused function declaration cpu_set_state_online()
  cpu/SMT: Fix cpu_smt_possible() comment
  cpu/SMT: Allow enabling partial SMT states via sysfs
  cpu/SMT: Create topology_smt_thread_allowed()
  cpu/SMT: Remove topology_smt_supported()
  cpu/SMT: Store the current/max number of threads
  cpu/SMT: Move smt/control simple exit cases earlier
  cpu/SMT: Move SMT prototypes into cpu_smt.h
  cpu/hotplug: Remove dependancy against cpu_primary_thread_mask
2023-08-28 15:04:43 -07:00
Eric DeVolder
88a6f89944 crash: memory and CPU hotplug sysfs attributes
Introduce the crash_hotplug attribute for memory and CPUs for use by
userspace.  These attributes directly facilitate the udev rule for
managing userspace re-loading of the crash kernel upon hot un/plug
changes.

For memory, expose the crash_hotplug attribute to the
/sys/devices/system/memory directory.  For example:

 # udevadm info --attribute-walk /sys/devices/system/memory/memory81
  looking at device '/devices/system/memory/memory81':
    KERNEL=="memory81"
    SUBSYSTEM=="memory"
    DRIVER==""
    ATTR{online}=="1"
    ATTR{phys_device}=="0"
    ATTR{phys_index}=="00000051"
    ATTR{removable}=="1"
    ATTR{state}=="online"
    ATTR{valid_zones}=="Movable"

  looking at parent device '/devices/system/memory':
    KERNELS=="memory"
    SUBSYSTEMS==""
    DRIVERS==""
    ATTRS{auto_online_blocks}=="offline"
    ATTRS{block_size_bytes}=="8000000"
    ATTRS{crash_hotplug}=="1"

For CPUs, expose the crash_hotplug attribute to the
/sys/devices/system/cpu directory. For example:

 # udevadm info --attribute-walk /sys/devices/system/cpu/cpu0
  looking at device '/devices/system/cpu/cpu0':
    KERNEL=="cpu0"
    SUBSYSTEM=="cpu"
    DRIVER=="processor"
    ATTR{crash_notes}=="277c38600"
    ATTR{crash_notes_size}=="368"
    ATTR{online}=="1"

  looking at parent device '/devices/system/cpu':
    KERNELS=="cpu"
    SUBSYSTEMS==""
    DRIVERS==""
    ATTRS{crash_hotplug}=="1"
    ATTRS{isolated}==""
    ATTRS{kernel_max}=="8191"
    ATTRS{nohz_full}=="  (null)"
    ATTRS{offline}=="4-7"
    ATTRS{online}=="0-3"
    ATTRS{possible}=="0-7"
    ATTRS{present}=="0-3"

With these sysfs attributes in place, it is possible to efficiently
instruct the udev rule to skip crash kernel reloading for kernels
configured with crash hotplug support.

For example, the following is the proposed udev rule change for RHEL
system 98-kexec.rules (as the first lines of the rule file):

 # The kernel updates the crash elfcorehdr for CPU and memory changes
 SUBSYSTEM=="cpu", ATTRS{crash_hotplug}=="1", GOTO="kdump_reload_end"
 SUBSYSTEM=="memory", ATTRS{crash_hotplug}=="1", GOTO="kdump_reload_end"

When examined in the context of 98-kexec.rules, the above rules test if
crash_hotplug is set, and if so, the userspace initiated
unload-then-reload of the crash kernel is skipped.

CPU and memory checks are separated in accordance with CONFIG_HOTPLUG_CPU
and CONFIG_MEMORY_HOTPLUG kernel config options.  If an architecture
supports, for example, memory hotplug but not CPU hotplug, then the
/sys/devices/system/memory/crash_hotplug attribute file is present, but
the /sys/devices/system/cpu/crash_hotplug attribute file will NOT be
present.  Thus the udev rule skips userspace processing of memory hot
un/plug events, but the udev rule will evaluate false for CPU events, thus
allowing userspace to process CPU hot un/plug events (ie the
unload-then-reload of the kdump capture kernel).

Link: https://lkml.kernel.org/r/20230814214446.6659-5-eric.devolder@oracle.com
Signed-off-by: Eric DeVolder <eric.devolder@oracle.com>
Reviewed-by: Sourabh Jain <sourabhjain@linux.ibm.com>
Acked-by: Hari Bathini <hbathini@linux.ibm.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Akhil Raj <lf32.dev@gmail.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Mimi Zohar <zohar@linux.ibm.com>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Weißschuh <linux@weissschuh.net>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-24 16:25:14 -07:00
Michael Ellerman
7f48405c3c cpu/SMT: Allow enabling partial SMT states via sysfs
Add support to the /sys/devices/system/cpu/smt/control interface for
enabling a specified number of SMT threads per core, including partial
SMT states where not all threads are brought online.

The current interface accepts "on" and "off", to enable either 1 or all
SMT threads per core.

This commit allows writing an integer, between 1 and the number of SMT
threads supported by the machine. Writing 1 is a synonym for "off", 2 or
more enables SMT with the specified number of threads.

When reading the file, if all threads are online "on" is returned, to
avoid changing behaviour for existing users. If some other number of
threads is online then the integer value is returned.

Architectures like x86 only supporting 1 thread or all threads, should not
define CONFIG_SMT_NUM_THREADS_DYNAMIC. Architecture supporting partial SMT
states, like PowerPC, should define it.

[ ldufour: Slightly reword the commit's description ]
[ ldufour: Remove switch() in __store_smt_control() ]
[ ldufour: Rix build issue in control_show() ]

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Laurent Dufour <ldufour@linux.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Link: https://lore.kernel.org/r/20230705145143.40545-8-ldufour@linux.ibm.com
2023-07-28 09:53:37 +02:00
Daniel Sneddon
8974eb5882 x86/speculation: Add Gather Data Sampling mitigation
Gather Data Sampling (GDS) is a hardware vulnerability which allows
unprivileged speculative access to data which was previously stored in
vector registers.

Intel processors that support AVX2 and AVX512 have gather instructions
that fetch non-contiguous data elements from memory. On vulnerable
hardware, when a gather instruction is transiently executed and
encounters a fault, stale data from architectural or internal vector
registers may get transiently stored to the destination vector
register allowing an attacker to infer the stale data using typical
side channel techniques like cache timing attacks.

This mitigation is different from many earlier ones for two reasons.
First, it is enabled by default and a bit must be set to *DISABLE* it.
This is the opposite of normal mitigation polarity. This means GDS can
be mitigated simply by updating microcode and leaving the new control
bit alone.

Second, GDS has a "lock" bit. This lock bit is there because the
mitigation affects the hardware security features KeyLocker and SGX.
It needs to be enabled and *STAY* enabled for these features to be
mitigated against GDS.

The mitigation is enabled in the microcode by default. Disable it by
setting gather_data_sampling=off or by disabling all mitigations with
mitigations=off. The mitigation status can be checked by reading:

    /sys/devices/system/cpu/vulnerabilities/gather_data_sampling

Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
2023-07-19 16:45:37 -07:00
Jonathan Corbet
e4624435f3 docs: arm64: Move arm64 documentation under Documentation/arch/
Architecture-specific documentation is being moved into Documentation/arch/
as a way of cleaning up the top-level documentation directory and making
the docs hierarchy more closely match the source hierarchy.  Move
Documentation/arm64 into arch/ (along with the Chinese equvalent
translations) and fix up documentation references.

Cc: Will Deacon <will@kernel.org>
Cc: Alex Shi <alexs@kernel.org>
Cc: Hu Haowen <src.res@email.cn>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Yantengsi <siyanteng@loongson.cn>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-06-21 08:51:51 -06:00
Linus Torvalds
f3dfe925f9 There's not a huge amount of activity in the docs tree this time around,
but a few significant changes even so:
 
 - A complete rewriting of the top-level index.rst file, which mostly
   reflects itself in a redone top page in the HTML-rendered docs.  The hope
   is that the new organization will be a friendlier starting point for
   both users and developers.
 
 - Some math-rendering improvements.
 
 - A coding-style.rst update on the use of BUG() and WARN()
 
 - A big maintainer-PHP guide update.
 
 - Some code-of-conduct updates
 
 - More Chinese translation work
 
 Plus the usual pile of typo fixes, corrections, and updates.
 -----BEGIN PGP SIGNATURE-----
 
 iQFDBAABCAAtFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAmM7BksPHGNvcmJldEBs
 d24ubmV0AAoJEBdDWhNsDH5Y8i4H/ihd1ppgVYy1yvFL3L1KkcsNyt3bFUa6hide
 qmkhqpzjsNmbTOaW19Y6epCzRzvxG7M9hzztIewt1BhRDvgRC8GaQNNRw/IBs0B6
 kprisINC2/ap4JjCroYWepfd+H8NSiVxqtd8hVSMWDSh2cK9vw0qVqQq59I+gght
 64pA4F2nPO6bamZzAELTdWRj0ITL1A/V/jYj+T074B094arc4HyekIQ5Jn9GTCmt
 jFBH9yxAb3l8K7KgzH7FgxKY/an0HxKDh4Cnx2Jv+dcocgCwy1iXCuyEZbFd9GEB
 UyhPcCyrIe/I2B9U9LrqLvXA8LW7jwE+MZMqZpaRkxcIdE2gEFQ=
 =M7tR
 -----END PGP SIGNATURE-----

Merge tag 'docs-6.1' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "There's not a huge amount of activity in the docs tree this time
  around, but a few significant changes even so:

   - A complete rewriting of the top-level index.rst file, which mostly
     reflects itself in a redone top page in the HTML-rendered docs. The
     hope is that the new organization will be a friendlier starting
     point for both users and developers.

   - Some math-rendering improvements.

   - A coding-style.rst update on the use of BUG() and WARN()

   - A big maintainer-PHP guide update.

   - Some code-of-conduct updates

   - More Chinese translation work

  Plus the usual pile of typo fixes, corrections, and updates"

* tag 'docs-6.1' of git://git.lwn.net/linux: (66 commits)
  checkpatch: warn on usage of VM_BUG_ON() and other BUG variants
  coding-style.rst: document BUG() and WARN() rules ("do not crash the kernel")
  Documentation: devres: add missing IO helper
  Documentation: devres: update IRQ helper
  Documentation/mm: modify page_referenced to folio_referenced
  Documentation/CoC: Reflect current CoC interpretation and practices
  docs/doc-guide: Add documentation on SPHINX_IMGMATH
  docs: process/5.Posting.rst: clarify use of Reported-by: tag
  docs, kprobes: Fix the wrong location of Kprobes
  docs: add a man-pages link to the front page
  docs: put atomic*.txt and memory-barriers.txt into the core-api book
  docs: move asm-annotations.rst into core-api
  docs: remove some index.rst cruft
  docs: reconfigure the HTML left column
  docs: Rewrite the front page
  docs: promote the title of process/index.rst
  Documentation: devres: add missing SPI helper
  Documentation: devres: add missing PINCTRL helpers
  docs: hugetlbpage.rst: fix a typo of hugepage size
  docs/zh_CN: Add new translation of admin-guide/bootconfig.rst
  ...
2022-10-03 10:23:32 -07:00
Randy Dunlap
8a7f0e8ab9 Documentation/ABI: correct possessive "its" typos
Correct all uses of "it's" that are meant to be possessive "its".

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20220801025207.29971-1-rdunlap@infradead.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-09-27 13:21:43 -06:00
Salvatore Bonaccorso
00da0cb385 Documentation/ABI: Mention retbleed vulnerability info file for sysfs
While reporting for the AMD retbleed vulnerability was added in

  6b80b59b3555 ("x86/bugs: Report AMD retbleed vulnerability")

the new sysfs file was not mentioned so far in the ABI documentation for
sysfs-devices-system-cpu. Fix that.

Fixes: 6b80b59b3555 ("x86/bugs: Report AMD retbleed vulnerability")
Signed-off-by: Salvatore Bonaccorso <carnil@debian.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20220801091529.325327-1-carnil@debian.org
2022-08-25 15:55:02 +02:00
Linus Torvalds
cfeafd9466 Driver core / kernfs changes for 6.0-rc1
Here is the set of driver core and kernfs changes for 6.0-rc1.
 
 "biggest" thing in here is some scalability improvements for kernfs for
 large systems.  Other than that, included in here are:
 	- arch topology and cache info changes that have been reviewed
 	  and discussed a lot.
 	- potential error path cleanup fixes
 	- deferred driver probe cleanups
 	- firmware loader cleanups and tweaks
 	- documentation updates
 	- other small things
 
 All of these have been in the linux-next tree for a while with no
 reported problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCYuqCnw8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+ym/JgCcCnaycJY00ZPRQm3LQCyzfJ0HgqoAn2qxGV+K
 NKycLeXZSnuvIA87dycE
 =/4Jk
 -----END PGP SIGNATURE-----

Merge tag 'driver-core-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core / kernfs updates from Greg KH:
 "Here is the set of driver core and kernfs changes for 6.0-rc1.

  The "biggest" thing in here is some scalability improvements for
  kernfs for large systems. Other than that, included in here are:

   - arch topology and cache info changes that have been reviewed and
     discussed a lot.

   - potential error path cleanup fixes

   - deferred driver probe cleanups

   - firmware loader cleanups and tweaks

   - documentation updates

   - other small things

  All of these have been in the linux-next tree for a while with no
  reported problems"

* tag 'driver-core-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (63 commits)
  docs: embargoed-hardware-issues: fix invalid AMD contact email
  firmware_loader: Replace kmap() with kmap_local_page()
  sysfs docs: ABI: Fix typo in comment
  kobject: fix Kconfig.debug "its" grammar
  kernfs: Fix typo 'the the' in comment
  docs: driver-api: firmware: add driver firmware guidelines. (v3)
  arch_topology: Fix cache attributes detection in the CPU hotplug path
  ACPI: PPTT: Leave the table mapped for the runtime usage
  cacheinfo: Use atomic allocation for percpu cache attributes
  drivers/base: fix userspace break from using bin_attributes for cpumap and cpulist
  MAINTAINERS: Change mentions of mpm to olivia
  docs: ABI: sysfs-devices-soc: Update Lee Jones' email address
  docs: ABI: sysfs-class-pwm: Update Lee Jones' email address
  Documentation/process: Add embargoed HW contact for LLVM
  Revert "kernfs: Change kernfs_notify_list to llist."
  ACPI: Remove the unused find_acpi_cpu_cache_topology()
  arch_topology: Warn that topology for nested clusters is not supported
  arch_topology: Add support for parsing sockets in /cpu-map
  arch_topology: Set cluster identifier in each core/thread from /cpu-map
  arch_topology: Limit span of cpu_clustergroup_mask()
  ...
2022-08-04 11:31:20 -07:00
Mauro Carvalho Chehab
1d248d2302 ABI: testing/sysfs-devices-system-cpu: remove duplicated core_id
This was already defined at stable/sysfs-devices-system-cpu with
the same description, as pointed by get_abi.pl:

	Warning: /sys/devices/system/cpu/cpuX/topology/core_id is defined 2 times:  Documentation/ABI/stable/sysfs-devices-system-cpu:38  Documentation/ABI/testing/sysfs-devices-system-cpu:69

Remove the duplicated one.

Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Link: https://lore.kernel.org/r/1e92337c1ef74f5eb9e1c1871e20b858b490d269.1656235926.git.mchehab@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-27 16:43:11 +02:00
Mark Brown
d69d564964 arm64/sme: Expose SMIDR through sysfs
We currently expose MIDR and REVID to userspace through sysfs to enable it
to make decisions based on the specific implementation. Since SME supports
implementations where streaming mode is provided by a separate hardware
unit called a SMCU it provides a similar ID register SMIDR. Expose it to
userspace via sysfs when the system supports SME along with the other ID
registers.

Since we disable the SME priority mapping feature if it is supported by
hardware we currently mask out the SMPS bit which reports that it is
supported.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220607132857.1358361-1-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2022-06-23 18:22:44 +01:00
Pawan Gupta
8d50cdf8b8 x86/speculation/mmio: Add sysfs reporting for Processor MMIO Stale Data
Add the sysfs reporting file for Processor MMIO Stale Data
vulnerability. It exposes the vulnerability and mitigation state similar
to the existing files for the other hardware vulnerabilities.

Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
2022-05-21 12:16:04 +02:00
Linus Torvalds
d752e21114 - Merge the AMD and Intel PPIN code into a shared one by both vendors.
Add the PPIN number to sysfs so that sockets can be identified when
 replacement is needed
 
 - Minor fixes and cleanups
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmI4UBcACgkQEsHwGGHe
 VUoDQw/9E2WVsLS+iVngYI5hY+LQbbeOLPt9sqgdf8U/4tQPwJfAKYRALQ3FvjbJ
 XKEqcHoCIBH0XQSC0TPpBF96VABr5Vrc/knV8x2OWJ82p54beB0rXh5mdsnsrVMQ
 7Gi00iEgZ1kw7TwRN7rMzUpudNOr7C/SSQL535hyZA4NT9QkNBObZWHMnojVnEmr
 AW1TY54xXSpu7xDY5ari5NGeSgvu1PIsCy0EKMK/SFLEpKQW4lt+lUe1aSieMarj
 xgnfIyGW3SUbadwlvLbIqVpR0RQBDLTabx8nyXnJAVZlwuAfioRUGL+Z4GFA0Y7q
 uDofxuScBAea3sPPFAAIoh13y595TjowBX7pHA1sqjWLmFKt6Qqz5dq1uBVEvIYw
 uTAQ/igJ4N2jq03jwnAw1LUAES5azSseCsiQxR7oqzK9KaRlptxHTAqhjqsgpIp4
 VLdYtgkzOEFiOsWsHWP1Dd+vzpMvTh5gtTXZuVcldo2D6scdcj+oaloHQ5XMiFu1
 GKuyiY4EbkRcp9ZQ847xOn4knEg+aq9zL0tJoWWEMKfRQn6425TEOLqkIdc9QfeU
 t63yqJ1q3NTjjzxzy/FdKwdoyOOQxeDl5YGPX3gZnj9X/0wgs+dHRmKp0o74SIg9
 4h2kB69wRwn6rC09P2UkQVGpDL0mnif4ZAh61vRE+mS0zSNCkEA=
 =MWVZ
 -----END PGP SIGNATURE-----

Merge tag 'x86_cpu_for_v5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 cpu feature updates from Borislav Petkov:

 - Merge the AMD and Intel PPIN code into a shared one by both vendors.
   Add the PPIN number to sysfs so that sockets can be identified when
   replacement is needed

 - Minor fixes and cleanups

* tag 'x86_cpu_for_v5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/cpu: Clear SME feature flag when not in use
  x86/cpufeatures: Put the AMX macros in the word 18 block
  topology/sysfs: Add PPIN in sysfs under cpu topology
  topology/sysfs: Add format parameter to macro defining "show" functions for proc
  x86/cpu: Read/save PPIN MSR during initialization
  x86/cpu: X86_FEATURE_INTEL_PPIN finally has a CPUID bit
  x86/cpu: Merge Intel and AMD ppin_init() functions
  x86/CPU/AMD: Use default_groups in kobj_type
2022-03-21 11:11:48 -07:00
Evgenii Stepanov
9986c7650e docs: sysfs-devices-system-cpu: document "asymm" value for mte_tcf_preferred
It was added in commit 766121ba5de3 ("arm64/mte: Add userspace interface
for enabling asymmetric mode").

Signed-off-by: Evgenii Stepanov <eugenis@google.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220309215943.87831-1-eugenis@google.com
Signed-off-by: Will Deacon <will@kernel.org>
2022-03-10 10:23:10 +00:00
Tony Luck
ab28e94419 topology/sysfs: Add PPIN in sysfs under cpu topology
PPIN is the Protected Processor Identification Number.
This is used to identify the socket as a Field Replaceable Unit (FRU).

Existing code only displays this when reporting errors. But this makes
it inconvenient for large clusters to use it for its intended purpose
of inventory control.

Add ppin to /sys/devices/system/cpu/cpu*/topology to make what
is already available using RDMSR more easily accessible. Make
the file read only for root in case there are still people
concerned about making a unique system "serial number" available.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20220131230111.2004669-6-tony.luck@intel.com
2022-02-01 16:36:42 +01:00
Kohei Tarumizu
02bf607413 docs: document the sysfs ABI for "isolated"
Add missing documentation of sysfs ABI for "isolated". It was added by
commit 59f30abe94bf("show isolated cpus in sysfs"). However, there is
no documentation for these interface.

Signed-off-by: Kohei Tarumizu <tarumizu.kohei@fujitsu.com>
Link: https://lore.kernel.org/r/20211201115957.254224-3-tarumizu.kohei@fujitsu.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-03 14:35:17 +01:00
Kohei Tarumizu
3722e7c3c6 docs: document the sysfs ABI for "nohz_full"
Add missing documentation of sysfs ABI for "nohz_full". It was added
by commit 6570a9a1ce3a("show nohz_full cpus in sysfs"). However,
there is no documentation for these interface.

Signed-off-by: Kohei Tarumizu <tarumizu.kohei@fujitsu.com>
Link: https://lore.kernel.org/r/20211201115957.254224-2-tarumizu.kohei@fujitsu.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-03 14:35:17 +01:00
Mauro Carvalho Chehab
abcb948db3 ABI: sysfs-devices-system-cpu: use cpuX instead of cpu#
Some What entries here use cpu# as a wildcard, while others
use, instead, cpuX.

As scripts/get_abi.pl doesn't consider "#" as a wildcard,
replace:

	cpu# -> cpuX

inside the file.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/60b1a79189d1a9d9f1c9c9c299770e69b18972fd.1632994837.git.mchehab+huawei@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-05 16:25:27 +02:00
Mauro Carvalho Chehab
26d6ba2f89 ABI: sysfs-devices-system-cpu: use wildcards on What definitions
An "N" upper letter is not a wildcard, nor can easily be identified
by script, specially since the USB sysfs define things like.
bNumInterfaces. Use, instead, <N>, in order to let script/get_abi.pl
to convert it into a Regex.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/d18385a391b6797373a5d1382ea024857fb29987.1631782432.git.mchehab+huawei@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-21 18:31:17 +02:00
Catalin Marinas
65266a7c6a Merge remote-tracking branch 'tip/sched/arm64' into for-next/core
* tip/sched/arm64: (785 commits)
  Documentation: arm64: describe asymmetric 32-bit support
  arm64: Remove logic to kill 32-bit tasks on 64-bit-only cores
  arm64: Hook up cmdline parameter to allow mismatched 32-bit EL0
  arm64: Advertise CPUs capable of running 32-bit applications in sysfs
  arm64: Prevent offlining first CPU with 32-bit EL0 on mismatched system
  arm64: exec: Adjust affinity for compat tasks with mismatched 32-bit EL0
  arm64: Implement task_cpu_possible_mask()
  sched: Introduce dl_task_check_affinity() to check proposed affinity
  sched: Allow task CPU affinity to be restricted on asymmetric systems
  sched: Split the guts of sched_setaffinity() into a helper function
  sched: Introduce task_struct::user_cpus_ptr to track requested affinity
  sched: Reject CPU affinity changes based on task_cpu_possible_mask()
  cpuset: Cleanup cpuset_cpus_allowed_fallback() use in select_fallback_rq()
  cpuset: Honour task_cpu_possible_mask() in guarantee_online_cpus()
  cpuset: Don't use the cpu_possible_mask as a last resort for cgroup v1
  sched: Introduce task_cpu_possible_mask() to limit fallback rq selection
  sched: Cgroup SCHED_IDLE support
  sched/topology: Skip updating masks for non-online nodes
  Linux 5.14-rc6
  lib: use PFN_PHYS() in devmem_is_allowed()
  ...
2021-08-31 09:10:00 +01:00
Will Deacon
7af33504d1 arm64: Advertise CPUs capable of running 32-bit applications in sysfs
Since 32-bit applications will be killed if they are caught trying to
execute on a 64-bit-only CPU in a mismatched system, advertise the set
of 32-bit capable CPUs to userspace in sysfs.

Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210730112443.23245-14-will@kernel.org
2021-08-20 12:33:07 +02:00
Peter Collingbourne
80c7c36fb3 Documentation: document the preferred tag checking mode feature
Document the functionality added in the previous patches.

Link: https://linux-review.googlesource.com/id/I48217cc3e8b8da33abc08cbaddc11cf4360a1b86
Signed-off-by: Peter Collingbourne <pcc@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210727205300.2554659-6-pcc@google.com
Acked-by: Will Deacon <will@kernel.org>
[catalin.marinas@arm.com: clarify that the change happens on task scheduling]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2021-07-28 18:39:26 +01:00
Carlos Bilbao
3e42d1de02 docs: typo fixes in Documentation/ABI/
Fix the following typos in the Documentation/ABI/ directory:

- In file obsolete/sysfs-cpuidle, change "obselete" for "obsolete".

- In file removed/sysfs-kernel-uids, change "propotional" for "proportional".

- In directory stable/, fix the following words: "associtated" for "associated",
  "hexidecimal" for "hexadecimal", "vlue" for "value", "csed" for "caused" and
  "wrtie" for "write". This updates a total of five files.

- In directory testing/, fix the following words: "subystem" for "subsystem",
  "isochrnous" for "isochronous", "Desctiptors" for "Descriptors", "picutre" for
  "picture", "capture" for "capture", "occured" for "ocurred", "connnected" for
  "connected","agressively" for "aggressively","manufacturee" for "manufacturer"
  and "transaction" for "transaction", "malformatted" for "incorrectly formated"
  ,"internel" for "internal", "writtento" for "written to", "specificed" for
  "specified", "beyound" for "beyond", "Symetric" for "Symmetric". This updates
  a total of eleven files.

Signed-off-by: Carlos Bilbao <bilbao@vt.edu>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/5710038.lOV4Wx5bFT@iron-maiden
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-13 09:13:25 -06:00
Anatoly Pugachev
2fa4928aed docs: correct URL to bios and kernel developer's guide
correct URL to bios and kernel developer's guide on amd.com site

Signed-off-by: Anatoly Pugachev <matorola@gmail.com>
Link: https://lore.kernel.org/r/20210428104851.GA10572@u164.east.ru
[jc: fixed resulting sphinx warning]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-03 17:22:44 -06:00
Ionela Voinescu
cfdc589f4b cppc_cpufreq: expose information on frequency domains
Use the existing sysfs attribute "freqdomain_cpus" to expose
information to userspace about CPUs in the same frequency domain.

Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Mian Yousaf Kaukab <ykaukab@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-12-15 19:19:32 +01:00
Mauro Carvalho Chehab
54a19b4d3f docs: ABI: cleanup several ABI documents
There are some ABI documents that, while they don't generate
any warnings, they have issues when parsed by get_abi.pl script
on its output result.

Address them, in order to provide a clean output.

Reviewed-by: Tom Rix <trix@redhat.com> # for fpga-manager
Reviewed-By: Kajol Jain<kjain@linux.ibm.com> # for sysfs-bus-event_source-devices-hv_gpci and sysfs-bus-event_source-devices-hv_24x7
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> #for IIO
Acked-by: Oded Gabbay <oded.gabbay@gmail.com> # for Habanalabs
Acked-by: Vaibhav Jain <vaibhav@linux.ibm.com> # for sysfs-bus-papr-pmem
Acked-by: Cezary Rojewski <cezary.rojewski@intel.com> # for catpt
Acked-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Ilya Dryomov <idryomov@gmail.com> # for rbd
Acked-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/5bc78e5b68ed1e9e39135173857cb2e753be868f.1604042072.git.mchehab+huawei@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-30 13:14:29 +01:00
Mauro Carvalho Chehab
3443333284 docs: ABI: testing: make the files compatible with ReST output
Some files over there won't parse well by Sphinx.

Fix them.

Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # for IIO
Acked-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Acked-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/58cf3c2d611e0197fb215652719ebd82ca2658db.1604042072.git.mchehab+huawei@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-30 13:07:01 +01:00
Linus Torvalds
8b4d37db9a Merge branch 'x86/srbds' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 srbds fixes from Thomas Gleixner:
 "The 9th episode of the dime novel "The performance killer" with the
  subtitle "Slow Randomizing Boosts Denial of Service".

  SRBDS is an MDS-like speculative side channel that can leak bits from
  the random number generator (RNG) across cores and threads. New
  microcode serializes the processor access during the execution of
  RDRAND and RDSEED. This ensures that the shared buffer is overwritten
  before it is released for reuse. This is equivalent to a full bus
  lock, which means that many threads running the RNG instructions in
  parallel have the same effect as the same amount of threads issuing a
  locked instruction targeting an address which requires locking of two
  cachelines at once.

  The mitigation support comes with the usual pile of unpleasant
  ingredients:

   - command line options

   - sysfs file

   - microcode checks

   - a list of vulnerable CPUs identified by model and stepping this
     time which requires stepping match support for the cpu match logic.

   - the inevitable slowdown of affected CPUs"

* branch 'x86/srbds' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/speculation: Add Ivy Bridge to affected list
  x86/speculation: Add SRBDS vulnerability and mitigation documentation
  x86/speculation: Add Special Register Buffer Data Sampling (SRBDS) mitigation
  x86/cpu: Add 'table' argument to cpu_matches()
2020-06-09 09:30:21 -07:00
Linus Torvalds
7ae77150d9 powerpc updates for 5.8
- Support for userspace to send requests directly to the on-chip GZIP
    accelerator on Power9.
 
  - Rework of our lockless page table walking (__find_linux_pte()) to make it
    safe against parallel page table manipulations without relying on an IPI for
    serialisation.
 
  - A series of fixes & enhancements to make our machine check handling more
    robust.
 
  - Lots of plumbing to add support for "prefixed" (64-bit) instructions on
    Power10.
 
  - Support for using huge pages for the linear mapping on 8xx (32-bit).
 
  - Remove obsolete Xilinx PPC405/PPC440 support, and an associated sound driver.
 
  - Removal of some obsolete 40x platforms and associated cruft.
 
  - Initial support for booting on Power10.
 
  - Lots of other small features, cleanups & fixes.
 
 Thanks to:
   Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Andrey Abramov,
   Aneesh Kumar K.V, Balamuruhan S, Bharata B Rao, Bulent Abali, Cédric Le
   Goater, Chen Zhou, Christian Zigotzky, Christophe JAILLET, Christophe Leroy,
   Dmitry Torokhov, Emmanuel Nicolet, Erhard F., Gautham R. Shenoy, Geoff Levand,
   George Spelvin, Greg Kurz, Gustavo A. R. Silva, Gustavo Walbon, Haren Myneni,
   Hari Bathini, Joel Stanley, Jordan Niethe, Kajol Jain, Kees Cook, Leonardo
   Bras, Madhavan Srinivasan., Mahesh Salgaonkar, Markus Elfring, Michael
   Neuling, Michal Simek, Nathan Chancellor, Nathan Lynch, Naveen N. Rao,
   Nicholas Piggin, Oliver O'Halloran, Paul Mackerras, Pingfan Liu, Qian Cai, Ram
   Pai, Raphael Moreira Zinsly, Ravi Bangoria, Sam Bobroff, Sandipan Das, Segher
   Boessenkool, Stephen Rothwell, Sukadev Bhattiprolu, Tyrel Datwyler, Wolfram
   Sang, Xiongfeng Wang.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCAAxFiEEJFGtCPCthwEv2Y/bUevqPMjhpYAFAl7aYZ8THG1wZUBlbGxl
 cm1hbi5pZC5hdQAKCRBR6+o8yOGlgPiKD/9zNCuZLFMAFrIdbm0HlYA2RGYZFT75
 GUHsqYyei1pxA7PgM3KwJiXELVODsBv0eQbgNh1tbecKrxPRegN/cywd1KLjPZ7I
 v5/qweQP8MvR0RhzjbhvUcO0jq/f8u2LbJr5mUfVzjU6tAvrvcWo3oZqDElsekCS
 kgyOH3r1vZ2PLTMiGFhb0gWi2iqc+6BHU1AFCGPCMjB1Vu5d5+54VvZ/6lllGsOF
 yg9CBXmmVvQ+Bn6tH4zdEB78FYxnAIwBqlbmL79i5ca+HQJ0Sw6HuPRy9XYq35p6
 2EiXS4Wrgp7i7+1TN3HO362u5Onb8TSyQU7NS6yCFPoJ6JQxcJMBIw6mHhnXOPuZ
 CrjgcdwUMjx8uDoKmX1Epbfuex2w+AysW+4yBHPFiSgl3klKC3D0wi95mR485w2F
 rN8uzJtrDeFKcYZJG7IoB/cgFCCPKGf9HaXr8q0S/jBKMffx91ul3cfzlfdIXOCw
 FDNw/+ZX7UD6ddFEG12ZTO+vdL8yf1uCRT/DIZwUiDMIA0+M6F4nc7j3lfyZfoO1
 65f9UlhoLxScq7VH2fKH4UtZatO9cPID2z1CmiY4UbUIPtFDepSuYClgLF+Duf4b
 rkfxhKU0+Ja1zNH5XNc+L+Bc5/W4lFiJXz02dYIjtHoUpWkc1aToOETVwzggYFNM
 G3PXIBOI0jRgRw==
 =o0WU
 -----END PGP SIGNATURE-----

Merge tag 'powerpc-5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

 - Support for userspace to send requests directly to the on-chip GZIP
   accelerator on Power9.

 - Rework of our lockless page table walking (__find_linux_pte()) to
   make it safe against parallel page table manipulations without
   relying on an IPI for serialisation.

 - A series of fixes & enhancements to make our machine check handling
   more robust.

 - Lots of plumbing to add support for "prefixed" (64-bit) instructions
   on Power10.

 - Support for using huge pages for the linear mapping on 8xx (32-bit).

 - Remove obsolete Xilinx PPC405/PPC440 support, and an associated sound
   driver.

 - Removal of some obsolete 40x platforms and associated cruft.

 - Initial support for booting on Power10.

 - Lots of other small features, cleanups & fixes.

Thanks to: Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan,
Andrey Abramov, Aneesh Kumar K.V, Balamuruhan S, Bharata B Rao, Bulent
Abali, Cédric Le Goater, Chen Zhou, Christian Zigotzky, Christophe
JAILLET, Christophe Leroy, Dmitry Torokhov, Emmanuel Nicolet, Erhard F.,
Gautham R. Shenoy, Geoff Levand, George Spelvin, Greg Kurz, Gustavo A.
R. Silva, Gustavo Walbon, Haren Myneni, Hari Bathini, Joel Stanley,
Jordan Niethe, Kajol Jain, Kees Cook, Leonardo Bras, Madhavan
Srinivasan., Mahesh Salgaonkar, Markus Elfring, Michael Neuling, Michal
Simek, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin,
Oliver O'Halloran, Paul Mackerras, Pingfan Liu, Qian Cai, Ram Pai,
Raphael Moreira Zinsly, Ravi Bangoria, Sam Bobroff, Sandipan Das, Segher
Boessenkool, Stephen Rothwell, Sukadev Bhattiprolu, Tyrel Datwyler,
Wolfram Sang, Xiongfeng Wang.

* tag 'powerpc-5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (299 commits)
  powerpc/pseries: Make vio and ibmebus initcalls pseries specific
  cxl: Remove dead Kconfig options
  powerpc: Add POWER10 architected mode
  powerpc/dt_cpu_ftrs: Add MMA feature
  powerpc/dt_cpu_ftrs: Enable Prefixed Instructions
  powerpc/dt_cpu_ftrs: Advertise support for ISA v3.1 if selected
  powerpc: Add support for ISA v3.1
  powerpc: Add new HWCAP bits
  powerpc/64s: Don't set FSCR bits in INIT_THREAD
  powerpc/64s: Save FSCR to init_task.thread.fscr after feature init
  powerpc/64s: Don't let DT CPU features set FSCR_DSCR
  powerpc/64s: Don't init FSCR_DSCR in __init_FSCR()
  powerpc/32s: Fix another build failure with CONFIG_PPC_KUAP_DEBUG
  powerpc/module_64: Use special stub for _mcount() with -mprofile-kernel
  powerpc/module_64: Simplify check for -mprofile-kernel ftrace relocations
  powerpc/module_64: Consolidate ftrace code
  powerpc/32: Disable KASAN with pages bigger than 16k
  powerpc/uaccess: Don't set KUEP by default on book3s/32
  powerpc/uaccess: Don't set KUAP by default on book3s/32
  powerpc/8xx: Reduce time spent in allow_user_access() and friends
  ...
2020-06-05 12:39:30 -07:00
Hanjun Guo
7395683a24 Documentation: cpuidle: update the document
Update the document after the remove of cpuidle_sysfs_switch.

Signed-off-by: Hanjun Guo <guohanjun@huawei.com>
Reviewed-by: Doug Smythies <dsmythies@telus.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-05-19 17:41:17 +02:00
Gautham R. Shenoy
bde752c3d6 Documentation: Document sysfs interfaces purr, spurr, idle_purr, idle_spurr
Add documentation for the following sysfs interfaces:
/sys/devices/system/cpu/cpuX/purr
/sys/devices/system/cpu/cpuX/spurr
/sys/devices/system/cpu/cpuX/idle_purr
/sys/devices/system/cpu/cpuX/idle_spurr

Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1586249263-14048-6-git-send-email-ego@linux.vnet.ibm.com
2020-04-30 12:35:27 +10:00
Mark Gross
7e5b3c267d x86/speculation: Add Special Register Buffer Data Sampling (SRBDS) mitigation
SRBDS is an MDS-like speculative side channel that can leak bits from the
random number generator (RNG) across cores and threads. New microcode
serializes the processor access during the execution of RDRAND and
RDSEED. This ensures that the shared buffer is overwritten before it is
released for reuse.

While it is present on all affected CPU models, the microcode mitigation
is not needed on models that enumerate ARCH_CAPABILITIES[MDS_NO] in the
cases where TSX is not supported or has been disabled with TSX_CTRL.

The mitigation is activated by default on affected processors and it
increases latency for RDRAND and RDSEED instructions. Among other
effects this will reduce throughput from /dev/urandom.

* Enable administrator to configure the mitigation off when desired using
  either mitigations=off or srbds=off.

* Export vulnerability status via sysfs

* Rename file-scoped macros to apply for non-whitelist table initializations.

 [ bp: Massage,
   - s/VULNBL_INTEL_STEPPING/VULNBL_INTEL_STEPPINGS/g,
   - do not read arch cap MSR a second time in tsx_fused_off() - just pass it in,
   - flip check in cpu_set_bug_bits() to save an indentation level,
   - reflow comments.
   jpoimboe: s/Mitigated/Mitigation/ in user-visible strings
   tglx: Dropped the fused off magic for now
 ]

Signed-off-by: Mark Gross <mgross@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Tested-by: Neelima Krishnan <neelima.krishnan@intel.com>
2020-04-20 12:19:22 +02:00
Rafael J. Wysocki
75a8026741 cpuidle: Allow idle states to be disabled by default
In certain situations it may be useful to prevent some idle states
from being used by default while allowing user space to enable them
later on.

For this purpose, introduce a new state flag, CPUIDLE_FLAG_OFF, to
mark idle states that should be disabled by default, make the core
set CPUIDLE_STATE_DISABLED_BY_USER for those states at the
initialization time and add a new state attribute in sysfs,
"default_status", to inform user space of the initial status of
the given idle state ("disabled" if CPUIDLE_FLAG_OFF is set for it,
"enabled" otherwise).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-12-27 11:02:08 +01:00
Vineela Tummalapalli
db4d30fbb7 x86/bugs: Add ITLB_MULTIHIT bug infrastructure
Some processors may incur a machine check error possibly resulting in an
unrecoverable CPU lockup when an instruction fetch encounters a TLB
multi-hit in the instruction TLB. This can occur when the page size is
changed along with either the physical address or cache type. The relevant
erratum can be found here:

   https://bugzilla.kernel.org/show_bug.cgi?id=205195

There are other processors affected for which the erratum does not fully
disclose the impact.

This issue affects both bare-metal x86 page tables and EPT.

It can be mitigated by either eliminating the use of large pages or by
using careful TLB invalidations when changing the page size in the page
tables.

Just like Spectre, Meltdown, L1TF and MDS, a new bit has been allocated in
MSR_IA32_ARCH_CAPABILITIES (PSCHANGE_MC_NO) and will be set on CPUs which
are mitigated against this issue.

Signed-off-by: Vineela Tummalapalli <vineela.tummalapalli@intel.com>
Co-developed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2019-11-04 12:22:01 +01:00
Pawan Gupta
a7a248c593 x86/speculation/taa: Add documentation for TSX Async Abort
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>
2019-10-28 08:37:00 +01:00
Ryan Grimm
734560ac39 powerpc/pseries/svm: Export guest SVM status to user space via sysfs
User space might want to know it's running in a secure VM.  It can't do
a mfmsr because mfmsr is a privileged instruction.

The solution here is to create a cpu attribute:

/sys/devices/system/cpu/svm

which will read 0 or 1 based on the S bit of the current CPU.

Signed-off-by: Ryan Grimm <grimm@linux.vnet.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820021326.6884-12-bauerman@linux.ibm.com
2019-08-30 09:55:41 +10:00
Mauro Carvalho Chehab
4f4cfa6c56 docs: admin-guide: add a series of orphaned documents
There are lots of documents that belong to the admin-guide but
are on random places (most under Documentation root dir).

Move them to the admin guide.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
2019-07-15 11:03:02 -03:00
Linus Torvalds
e9a83bd232 It's been a relatively busy cycle for docs:
- A fair pile of RST conversions, many from Mauro.  These create more
    than the usual number of simple but annoying merge conflicts with other
    trees, unfortunately.  He has a lot more of these waiting on the wings
    that, I think, will go to you directly later on.
 
  - A new document on how to use merges and rebases in kernel repos, and one
    on Spectre vulnerabilities.
 
  - Various improvements to the build system, including automatic markup of
    function() references because some people, for reasons I will never
    understand, were of the opinion that :c:func:``function()`` is
    unattractive and not fun to type.
 
  - We now recommend using sphinx 1.7, but still support back to 1.4.
 
  - Lots of smaller improvements, warning fixes, typo fixes, etc.
 -----BEGIN PGP SIGNATURE-----
 
 iQFDBAABCAAtFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAl0krAEPHGNvcmJldEBs
 d24ubmV0AAoJEBdDWhNsDH5Yg98H/AuLqO9LpOgUjF4LhyjxGPdzJkY9RExSJ7km
 gznyreLCZgFaJR+AY6YDsd4Jw6OJlPbu1YM/Qo3C3WrZVFVhgL/s2ebvBgCo50A8
 raAFd8jTf4/mGCHnAqRotAPQ3mETJUk315B66lBJ6Oc+YdpRhwXWq8ZW2bJxInFF
 3HDvoFgMf0KhLuMHUkkL0u3fxH1iA+KvDu8diPbJYFjOdOWENz/CV8wqdVkXRSEW
 DJxIq89h/7d+hIG3d1I7Nw+gibGsAdjSjKv4eRKauZs4Aoxd1Gpl62z0JNk6aT3m
 dtq4joLdwScydonXROD/Twn2jsu4xYTrPwVzChomElMowW/ZBBY=
 =D0eO
 -----END PGP SIGNATURE-----

Merge tag 'docs-5.3' of git://git.lwn.net/linux

Pull Documentation updates from Jonathan Corbet:
 "It's been a relatively busy cycle for docs:

   - A fair pile of RST conversions, many from Mauro. These create more
     than the usual number of simple but annoying merge conflicts with
     other trees, unfortunately. He has a lot more of these waiting on
     the wings that, I think, will go to you directly later on.

   - A new document on how to use merges and rebases in kernel repos,
     and one on Spectre vulnerabilities.

   - Various improvements to the build system, including automatic
     markup of function() references because some people, for reasons I
     will never understand, were of the opinion that
     :c:func:``function()`` is unattractive and not fun to type.

   - We now recommend using sphinx 1.7, but still support back to 1.4.

   - Lots of smaller improvements, warning fixes, typo fixes, etc"

* tag 'docs-5.3' of git://git.lwn.net/linux: (129 commits)
  docs: automarkup.py: ignore exceptions when seeking for xrefs
  docs: Move binderfs to admin-guide
  Disable Sphinx SmartyPants in HTML output
  doc: RCU callback locks need only _bh, not necessarily _irq
  docs: format kernel-parameters -- as code
  Doc : doc-guide : Fix a typo
  platform: x86: get rid of a non-existent document
  Add the RCU docs to the core-api manual
  Documentation: RCU: Add TOC tree hooks
  Documentation: RCU: Rename txt files to rst
  Documentation: RCU: Convert RCU UP systems to reST
  Documentation: RCU: Convert RCU linked list to reST
  Documentation: RCU: Convert RCU basic concepts to reST
  docs: filesystems: Remove uneeded .rst extension on toctables
  scripts/sphinx-pre-install: fix out-of-tree build
  docs: zh_CN: submitting-drivers.rst: Remove a duplicated Documentation/
  Documentation: PGP: update for newer HW devices
  Documentation: Add section about CPU vulnerabilities for Spectre
  Documentation: platform: Delete x86-laptop-drivers.txt
  docs: Note that :c:func: should no longer be used
  ...
2019-07-09 12:34:26 -07:00
Fenghua Yu
203dffacf5 Documentation/ABI: Document umwait control sysfs interfaces
Since two new sysfs interface files are created for umwait control, add
an ABI document entry for the files:

   /sys/devices/system/cpu/umwait_control/enable_c02
   /sys/devices/system/cpu/umwait_control/max_time

[ tglx: Made the write value instructions readable ]

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Cc: "Borislav Petkov" <bp@alien8.de>
Cc: "H Peter Anvin" <hpa@zytor.com>
Cc: "Andy Lutomirski" <luto@kernel.org>
Cc: "Peter Zijlstra" <peterz@infradead.org>
Cc: "Tony Luck" <tony.luck@intel.com>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Link: https://lkml.kernel.org/r/1560994438-235698-6-git-send-email-fenghua.yu@intel.com
2019-06-24 01:44:35 +02:00
Mauro Carvalho Chehab
671c30957e ABI: sysfs-devices-system-cpu: point to the right docs
The cpuidle doc was split on two, one at the admin guide
and another one at the driver API guide. Instead of pointing
to a non-existent file, point to both (admin guide being
the first one).

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-08 13:42:10 -06:00
Linus Torvalds
fa4bff1650 Merge branch 'x86-mds-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 MDS mitigations from Thomas Gleixner:
 "Microarchitectural Data Sampling (MDS) is a hardware vulnerability
  which allows unprivileged speculative access to data which is
  available in various CPU internal buffers. This new set of misfeatures
  has the following CVEs assigned:

     CVE-2018-12126  MSBDS  Microarchitectural Store Buffer Data Sampling
     CVE-2018-12130  MFBDS  Microarchitectural Fill Buffer Data Sampling
     CVE-2018-12127  MLPDS  Microarchitectural Load Port Data Sampling
     CVE-2019-11091  MDSUM  Microarchitectural Data Sampling Uncacheable Memory

  MDS attacks target microarchitectural buffers which speculatively
  forward data under certain conditions. Disclosure gadgets can expose
  this data via cache side channels.

  Contrary to other speculation based vulnerabilities the MDS
  vulnerability does not allow the attacker to control the memory target
  address. As a consequence the attacks are purely sampling based, but
  as demonstrated with the TLBleed attack samples can be postprocessed
  successfully.

  The mitigation is to flush the microarchitectural buffers on return to
  user space and before entering a VM. It's bolted on the VERW
  instruction and requires a microcode update. As some of the attacks
  exploit data structures shared between hyperthreads, full protection
  requires to disable hyperthreading. The kernel does not do that by
  default to avoid breaking unattended updates.

  The mitigation set comes with documentation for administrators and a
  deeper technical view"

* 'x86-mds-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  x86/speculation/mds: Fix documentation typo
  Documentation: Correct the possible MDS sysfs values
  x86/mds: Add MDSUM variant to the MDS documentation
  x86/speculation/mds: Add 'mitigations=' support for MDS
  x86/speculation/mds: Print SMT vulnerable on MSBDS with mitigations off
  x86/speculation/mds: Fix comment
  x86/speculation/mds: Add SMT warning message
  x86/speculation: Move arch_smt_update() call to after mitigation decisions
  x86/speculation/mds: Add mds=full,nosmt cmdline option
  Documentation: Add MDS vulnerability documentation
  Documentation: Move L1TF to separate directory
  x86/speculation/mds: Add mitigation mode VMWERV
  x86/speculation/mds: Add sysfs reporting for MDS
  x86/speculation/mds: Add mitigation control for MDS
  x86/speculation/mds: Conditionally clear CPU buffers on idle entry
  x86/kvm/vmx: Add MDS protection when L1D Flush is not active
  x86/speculation/mds: Clear CPU buffers on exit to user
  x86/speculation/mds: Add mds_clear_cpu_buffers()
  x86/kvm: Expose X86_FEATURE_MD_CLEAR to guests
  x86/speculation/mds: Add BUG_MSBDS_ONLY
  ...
2019-05-14 07:57:29 -07:00
Linus Torvalds
8f5e823f91 Power management updates for 5.2-rc1
- Fix the handling of Performance and Energy Bias Hint (EPB) on
    Intel processors and expose it to user space via sysfs to avoid
    having to access it through the generic MSR I/F (Rafael Wysocki).
 
  - Improve the handling of global turbo changes made by the platform
    firmware in the intel_pstate driver (Rafael Wysocki).
 
  - Convert some slow-path static_cpu_has() callers to boot_cpu_has()
    in cpufreq (Borislav Petkov).
 
  - Fix the frequency calculation loop in the armada-37xx cpufreq
    driver (Gregory CLEMENT).
 
  - Fix possible object reference leaks in multuple cpufreq drivers
    (Wen Yang).
 
  - Fix kerneldoc comment in the centrino cpufreq driver (dongjian).
 
  - Clean up the ACPI and maple cpufreq drivers (Viresh Kumar, Mohan
    Kumar).
 
  - Add support for lx2160a and ls1028a to the qoriq cpufreq driver
    (Vabhav Sharma, Yuantian Tang).
 
  - Fix kobject memory leak in the cpufreq core (Viresh Kumar).
 
  - Simplify the IOwait boosting in the schedutil cpufreq governor
    and rework the TSC cpufreq notifier on x86 (Rafael Wysocki).
 
  - Clean up the cpufreq core and statistics code (Yue Hu, Kyle Lin).
 
  - Improve the cpufreq documentation, add SPDX license tags to
    some PM documentation files and unify copyright notices in
    them (Rafael Wysocki).
 
  - Add support for "CPU" domains to the generic power domains (genpd)
    framework and provide low-level PSCI firmware support for that
    feature (Ulf Hansson).
 
  - Rearrange the PSCI firmware support code and add support for
    SYSTEM_RESET2 to it (Ulf Hansson, Sudeep Holla).
 
  - Improve genpd support for devices in multiple power domains (Ulf
    Hansson).
 
  - Unify target residency for the AFTR and coupled AFTR states in the
    exynos cpuidle driver (Marek Szyprowski).
 
  - Introduce new helper routine in the operating performance points
    (OPP) framework (Andrew-sh.Cheng).
 
  - Add support for passing on-die termination (ODT) and auto power
    down parameters from the kernel to Trusted Firmware-A (TF-A) to
    the rk3399_dmc devfreq driver (Enric Balletbo i Serra).
 
  - Add tracing to devfreq (Lukasz Luba).
 
  - Make the exynos-bus devfreq driver suspend all devices on system
    shutdown (Marek Szyprowski).
 
  - Fix a few minor issues in the devfreq subsystem and clean it up
    somewhat (Enric Balletbo i Serra, MyungJoo Ham, Rob Herring,
    Saravana Kannan, Yangtao Li).
 
  - Improve system wakeup diagnostics (Stephen Boyd).
 
  - Rework filesystem sync messages emitted during system suspend and
    hibernation (Harry Pan).
 -----BEGIN PGP SIGNATURE-----
 
 iQJGBAABCAAwFiEE4fcc61cGeeHD/fCwgsRv/nhiVHEFAlzQEwUSHHJqd0Byand5
 c29ja2kubmV0AAoJEILEb/54YlRxxXwP/jrxikIXdCOV3CJVioV0NetyebwlOqYp
 UsIA7lQBfZ/DY6dHw/oKuAT9LP01vcFg6XGe83Alkta9qczR5KZ/MYHFNSZXjXjL
 kEvIMBCS/oykaBuW+Xn9am8Ke3Yq/rBSTKWVom3vzSQY0qvZ9GBwPDrzw+k63Zhz
 P3afB4ThyY0e9ftgw4HvSSNm13Kn0ItUIQOdaLatXMMcPqP5aAdnUma5Ibinbtpp
 rpTHuHKYx7MSjaCg6wl3kKTJeWbQP4wYO2ISZqH9zEwQgdvSHeFAvfPKTegUkmw9
 uUsQnPD1JvdglOKovr2muehD1Ur+zsjKDf2OKERkWsWXHPyWzA/AqaVv1mkkU++b
 KaWaJ9pE86kGlJ3EXwRbGfV0dM5rrl+dUUQW6nPI1XJnIOFlK61RzwAbqI26F0Mz
 AlKxY4jyPLcM3SpQz9iILqyzHQqB67rm29XvId/9scoGGgoqEI4S+v6LYZqI3Vx6
 aeSRu+Yof7p5w4Kg5fODX+HzrtMnMrPmLUTXhbExfsYZMi7hXURcN6s+tMpH0ckM
 4yiIpnNGCKUSV4vxHBm8XJdAuUnR4Vcz++yFslszgDVVvw5tkvF7SYeHZ6HqcQVm
 af9HdWzx3qajs/oyBwdRBedZYDnP1joC5donBI2ofLeF33NA7TEiPX8Zebw8XLkv
 fNikssA7PGdv
 =nY9p
 -----END PGP SIGNATURE-----

Merge tag 'pm-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management updates from Rafael Wysocki:
 "These fix the (Intel-specific) Performance and Energy Bias Hint (EPB)
  handling and expose it to user space via sysfs, fix and clean up
  several cpufreq drivers, add support for two new chips to the qoriq
  cpufreq driver, fix, simplify and clean up the cpufreq core and the
  schedutil governor, add support for "CPU" domains to the generic power
  domains (genpd) framework and provide low-level PSCI firmware support
  for that feature, fix the exynos cpuidle driver and fix a couple of
  issues in the devfreq subsystem and clean it up.

  Specifics:

   - Fix the handling of Performance and Energy Bias Hint (EPB) on Intel
     processors and expose it to user space via sysfs to avoid having to
     access it through the generic MSR I/F (Rafael Wysocki).

   - Improve the handling of global turbo changes made by the platform
     firmware in the intel_pstate driver (Rafael Wysocki).

   - Convert some slow-path static_cpu_has() callers to boot_cpu_has()
     in cpufreq (Borislav Petkov).

   - Fix the frequency calculation loop in the armada-37xx cpufreq
     driver (Gregory CLEMENT).

   - Fix possible object reference leaks in multuple cpufreq drivers
     (Wen Yang).

   - Fix kerneldoc comment in the centrino cpufreq driver (dongjian).

   - Clean up the ACPI and maple cpufreq drivers (Viresh Kumar, Mohan
     Kumar).

   - Add support for lx2160a and ls1028a to the qoriq cpufreq driver
     (Vabhav Sharma, Yuantian Tang).

   - Fix kobject memory leak in the cpufreq core (Viresh Kumar).

   - Simplify the IOwait boosting in the schedutil cpufreq governor and
     rework the TSC cpufreq notifier on x86 (Rafael Wysocki).

   - Clean up the cpufreq core and statistics code (Yue Hu, Kyle Lin).

   - Improve the cpufreq documentation, add SPDX license tags to some PM
     documentation files and unify copyright notices in them (Rafael
     Wysocki).

   - Add support for "CPU" domains to the generic power domains (genpd)
     framework and provide low-level PSCI firmware support for that
     feature (Ulf Hansson).

   - Rearrange the PSCI firmware support code and add support for
     SYSTEM_RESET2 to it (Ulf Hansson, Sudeep Holla).

   - Improve genpd support for devices in multiple power domains (Ulf
     Hansson).

   - Unify target residency for the AFTR and coupled AFTR states in the
     exynos cpuidle driver (Marek Szyprowski).

   - Introduce new helper routine in the operating performance points
     (OPP) framework (Andrew-sh.Cheng).

   - Add support for passing on-die termination (ODT) and auto power
     down parameters from the kernel to Trusted Firmware-A (TF-A) to the
     rk3399_dmc devfreq driver (Enric Balletbo i Serra).

   - Add tracing to devfreq (Lukasz Luba).

   - Make the exynos-bus devfreq driver suspend all devices on system
     shutdown (Marek Szyprowski).

   - Fix a few minor issues in the devfreq subsystem and clean it up
     somewhat (Enric Balletbo i Serra, MyungJoo Ham, Rob Herring,
     Saravana Kannan, Yangtao Li).

   - Improve system wakeup diagnostics (Stephen Boyd).

   - Rework filesystem sync messages emitted during system suspend and
     hibernation (Harry Pan)"

* tag 'pm-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (72 commits)
  cpufreq: Fix kobject memleak
  cpufreq: armada-37xx: fix frequency calculation for opp
  cpufreq: centrino: Fix centrino_setpolicy() kerneldoc comment
  cpufreq: qoriq: add support for lx2160a
  x86: tsc: Rework time_cpufreq_notifier()
  PM / Domains: Allow to attach a CPU via genpd_dev_pm_attach_by_id|name()
  PM / Domains: Search for the CPU device outside the genpd lock
  PM / Domains: Drop unused in-parameter to some genpd functions
  PM / Domains: Use the base device for driver_deferred_probe_check_state()
  cpufreq: qoriq: Add ls1028a chip support
  PM / Domains: Enable genpd_dev_pm_attach_by_id|name() for single PM domain
  PM / Domains: Allow OF lookup for multi PM domain case from ->attach_dev()
  PM / Domains: Don't kfree() the virtual device in the error path
  cpufreq: Move ->get callback check outside of __cpufreq_get()
  PM / Domains: remove unnecessary unlikely()
  cpufreq: Remove needless bios_limit check in show_bios_limit()
  drivers/cpufreq/acpi-cpufreq.c: This fixes the following checkpatch warning
  firmware/psci: add support for SYSTEM_RESET2
  PM / devfreq: add tracing for scheduling work
  trace: events: add devfreq trace event file
  ...
2019-05-06 19:40:31 -07:00
Rafael J. Wysocki
b9c273babc PM / arch: x86: MSR_IA32_ENERGY_PERF_BIAS sysfs interface
The Performance and Energy Bias Hint (EPB) is expected to be set by
user space through the generic MSR interface, but that interface is
not particularly nice and there are security concerns regarding it,
so it is not always available.

For this reason, add a sysfs interface for reading and updating the
EPB, in the form of a new attribute, energy_perf_bias, located
under /sys/devices/system/cpu/cpu#/power/ for online CPUs that
support the EPB feature.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Acked-by: Borislav Petkov <bp@suse.de>
2019-04-07 22:33:42 +02:00
Josh Poimboeuf
de7b77e5bb cpu/hotplug: Create SMT sysfs interface for all arches
Make the /sys/devices/system/cpu/smt/* files available on all arches, so
user space has a consistent way to detect whether SMT is enabled.

The 'control' file now shows 'notimplemented' for architectures which
don't yet have CONFIG_HOTPLUG_SMT.

[ tglx: Make notimplemented a real state ]

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Kosina <jikos@kernel.org>
Link: https://lkml.kernel.org/r/469c2b98055f2c41e75748e06447d592a64080c9.1553635520.git.jpoimboe@redhat.com
2019-04-02 12:36:56 +02:00
Thomas Gleixner
5999bbe7a6 Documentation: Add MDS vulnerability documentation
Add the initial MDS vulnerability documentation.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jon Masters <jcm@redhat.com>
2019-03-06 21:52:16 +01:00
Thomas Gleixner
65fd4cb65b Documentation: Move L1TF to separate directory
Move L!TF to a separate directory so the MDS stuff can be added at the
side. Otherwise the all hardware vulnerabilites have their own top level
entry. Should have done that right away.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jon Masters <jcm@redhat.com>
2019-03-06 21:52:15 +01:00
Thomas Gleixner
8a4b06d391 x86/speculation/mds: Add sysfs reporting for MDS
Add the sysfs reporting file for MDS. It exposes the vulnerability and
mitigation state similar to the existing files for the other speculative
hardware vulnerabilities.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
2019-03-06 21:52:14 +01:00
Rafael J. Wysocki
04dab58a39 cpuidle: Add 'above' and 'below' idle state metrics
Add two new metrics for CPU idle states, "above" and "below", to count
the number of times the given state had been asked for (or entered
from the kernel's perspective), but the observed idle duration turned
out to be too short or too long for it (respectively).

These metrics help to estimate the quality of the CPU idle governor
in use.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-12-12 23:22:18 +01:00