linux.git/Documentation/x86, branch v5.13 Linux kernel source tree x86/msr: Rename MSR_K8_SYSCFG to MSR_AMD64_SYSCFG 2021-05-10T05:51:38+00:00 Brijesh Singh brijesh.singh@amd.com 2021-04-27T11:16:36+00:00 059e5c321a65657877924256ea8ad9c0df257b45 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 
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
Merge tag 'docs-5.13-2' of git://git.lwn.net/linux 2021-05-06T15:33:54+00:00 Linus Torvalds torvalds@linux-foundation.org 2021-05-06T15:33:54+00:00 a3f53e8adfda814730c341ee39ce015a0abf69aa 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 
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
docs: Fix typo in Documentation/x86/x86_64/5level-paging.rst 2021-04-27T19:03:30+00:00 bilbao@vt.edu bilbao@vt.edu 2021-04-27T17:28:29+00:00 6a79162fe5d5e0eb55bc48e99450982b0daf0a0f 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> 
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>
x86/sgx: Introduce virtual EPC for use by KVM guests 2021-04-06T07:43:17+00:00 Sean Christopherson sean.j.christopherson@intel.com 2021-03-19T07:22:21+00:00 540745ddbc70eabdc7dbd3fcc00fe4fb17cd59ba 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 
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
x86/sgx: Wipe out EREMOVE from sgx_free_epc_page() 2021-03-26T21:51:23+00:00 Kai Huang kai.huang@intel.com 2021-03-25T09:30:57+00:00 b0c7459be0670fabe080e30906ba9fe62df5e02c 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 
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
Documentation/x86/boot.rst: Correct the example of SETUP_INDIRECT 2021-01-28T22:25:31+00:00 Cao jin jojing64@gmail.com 2021-01-27T08:49:11+00:00 bcadb65fd64889cc3cf1ca4b8025d91b59ec1b02 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> 
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>
Merge tag 'docs-5.11' of git://git.lwn.net/linux 2020-12-15T00:55:54+00:00 Linus Torvalds torvalds@linux-foundation.org 2020-12-15T00:55:54+00:00 ff6135959a9150ad45cb92ca38da270903a74343 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 ... 
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
  ...
Merge tag 'x86_cache_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2020-12-14T21:53:17+00:00 Linus Torvalds torvalds@linux-foundation.org 2020-12-14T21:53:17+00:00 8ba27ae36b416a1507e783dbee4bb521fd6bb519 Pull x86 cache resource control updates from Borislav Petkov: - add logic to correct MBM total and local values fixing errata SKX99 and BDF102 (Fenghua Yu) - cleanups * tag 'x86_cache_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/resctrl: Clean up unused function parameter in rmdir path x86/resctrl: Constify kernfs_ops x86/resctrl: Correct MBM total and local values Documentation/x86: Rename resctrl_ui.rst and add two errata to the file 
Pull x86 cache resource control updates from Borislav Petkov:

 - add logic to correct MBM total and local values fixing errata SKX99
   and BDF102 (Fenghua Yu)

 - cleanups

* tag 'x86_cache_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/resctrl: Clean up unused function parameter in rmdir path
  x86/resctrl: Constify kernfs_ops
  x86/resctrl: Correct MBM total and local values
  Documentation/x86: Rename resctrl_ui.rst and add two errata to the file
Merge tag 'x86_cpu_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2020-12-14T21:21:33+00:00 Linus Torvalds torvalds@linux-foundation.org 2020-12-14T21:21:33+00:00 0d712978dcdd9c4fb2c4e4ef7700ee755184f11d Pull x86 cpuid updates from Borislav Petkov: "Only AMD-specific changes this time: - Save the AMD physical die ID into cpuinfo_x86.cpu_die_id and convert all code to use it (Yazen Ghannam) - Remove a dead and unused TSEG region remapping workaround on AMD (Arvind Sankar)" * tag 'x86_cpu_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpu/amd: Remove dead code for TSEG region remapping x86/topology: Set cpu_die_id only if DIE_TYPE found EDAC/mce_amd: Use struct cpuinfo_x86.cpu_die_id for AMD NodeId x86/CPU/AMD: Remove amd_get_nb_id() x86/CPU/AMD: Save AMD NodeId as cpu_die_id 
Pull x86 cpuid updates from Borislav Petkov:
 "Only AMD-specific changes this time:

   - Save the AMD physical die ID into cpuinfo_x86.cpu_die_id and
     convert all code to use it (Yazen Ghannam)

   - Remove a dead and unused TSEG region remapping workaround on AMD
     (Arvind Sankar)"

* tag 'x86_cpu_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/cpu/amd: Remove dead code for TSEG region remapping
  x86/topology: Set cpu_die_id only if DIE_TYPE found
  EDAC/mce_amd: Use struct cpuinfo_x86.cpu_die_id for AMD NodeId
  x86/CPU/AMD: Remove amd_get_nb_id()
  x86/CPU/AMD: Save AMD NodeId as cpu_die_id
docs: archis: add a per-architecture features list 2020-12-03T22:10:15+00:00 Mauro Carvalho Chehab mchehab+huawei@kernel.org 2020-11-30T15:36:35+00:00 ed13a92d0fdec0f36791343d39bc646d91cd7d98 Add a feature list matrix for each architecture to their respective Kernel books. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/9c39d4dd93e05c0008205527d2c3450912f029ed.1606748711.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net> 
Add a feature list matrix for each architecture to their
respective Kernel books.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/9c39d4dd93e05c0008205527d2c3450912f029ed.1606748711.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>