The guidelines for git commit ID abbreviation are inconsistent: some
places state to use 12 characters exactly, while other places recommend
12 characters or more.  The same issue is present in the checkpatch.pl
script.

E.g. Documentation/dev-tools/checkpatch.rst says:

  **GIT_COMMIT_ID**
    The proper way to reference a commit id is:
    commit <12+ chars of sha1> ("<title line>")

However, scripts/checkpatch.pl has two different checks: one warning
check accepting 12 characters exactly:

    # Check Fixes: styles is correct
    Please use correct Fixes: style 'Fixes: <12 chars of sha1> (\"<title line>\")'

and a second error check accepting 12-40 characters:

    # Check for git id commit length and improperly formed commit descriptions
    # A correctly formed commit description is:
    #    commit <SHA-1 hash length 12+ chars> ("Complete commit subject")
    Please use git commit description style 'commit <12+ chars of sha1>

Hence patches containing commit IDs with more than 12 characters are
flagged by checkpatch, and sometimes rejected by maintainers or
reviewers.  This is becoming more important with the growth of the
repository, as git may decide to use more characters in case of local
conflicts.

Fix this by settling on at least 12 characters, in both the
documentation and in the checkpatch.pl script.

Fixes: bd17e036b495bebb ("checkpatch: warn for non-standard fixes tag style")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/1c244040bf6ce304656e31036e5178b4b9dfb719.1733421037.git.geert+renesas@glider.be
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Fix typos in documentation: a -> an.

Signed-off-by: Andrew Kreimer <algonell@gmail.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20241027125712.19141-1-algonell@gmail.com

Fix typos in documentation.

Signed-off-by: Andrew Kreimer <algonell@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20240907122534.15998-1-algonell@gmail.com>

Based on multiple conversations, most recently on the ksummit mailing
list [1], add some best practices for using the Link trailer, such as:

- how to use markdown-like bracketed numbers in the commit message to
indicate the corresponding link
- when to use lore.kernel.org vs patch.msgid.link domains

Cc: ksummit@lists.linux.dev
Link: https://lore.kernel.org/20240617-arboreal-industrious-hedgehog-5b84ae@meerkat # [1]
Signed-off-by: Konstantin Ryabitsev <konstantin@linuxfoundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20240619-docs-patch-msgid-link-v2-2-72dd272bfe37@linuxfoundation.org

There are lots of maintainers "pings" during the merge window, even
for trivial patches.

Clarify that contributors should not expect progress on *any*
non-urgent patches during the merge window.  This applies to all
contributions, not just large ones.

Clarify the language around -rc1.  Trees really are closed during the
merge window.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/all/20240322183403.67BAEEFE%40davehans-spike.ostc.intel.com

Document when C++-style, tail comments should be used.

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240130193102.GEZblOdor_bzoVhT0f@fat_crate.local

Document where Closes: lands in the tag ordering.

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240124205442.GAZbF5EmOB8LpKqlSc@fat_crate.local

Pull kvm updates from Paolo Bonzini:
 "ARM64:

   - Eager page splitting optimization for dirty logging, optionally
     allowing for a VM to avoid the cost of hugepage splitting in the
     stage-2 fault path.

   - Arm FF-A proxy for pKVM, allowing a pKVM host to safely interact
     with services that live in the Secure world. pKVM intervenes on
     FF-A calls to guarantee the host doesn't misuse memory donated to
     the hyp or a pKVM guest.

   - Support for running the split hypervisor with VHE enabled, known as
     'hVHE' mode. This is extremely useful for testing the split
     hypervisor on VHE-only systems, and paves the way for new use cases
     that depend on having two TTBRs available at EL2.

   - Generalized framework for configurable ID registers from userspace.
     KVM/arm64 currently prevents arbitrary CPU feature set
     configuration from userspace, but the intent is to relax this
     limitation and allow userspace to select a feature set consistent
     with the CPU.

   - Enable the use of Branch Target Identification (FEAT_BTI) in the
     hypervisor.

   - Use a separate set of pointer authentication keys for the
     hypervisor when running in protected mode, as the host is untrusted
     at runtime.

   - Ensure timer IRQs are consistently released in the init failure
     paths.

   - Avoid trapping CTR_EL0 on systems with Enhanced Virtualization
     Traps (FEAT_EVT), as it is a register commonly read from userspace.

   - Erratum workaround for the upcoming AmpereOne part, which has
     broken hardware A/D state management.

  RISC-V:

   - Redirect AMO load/store misaligned traps to KVM guest

   - Trap-n-emulate AIA in-kernel irqchip for KVM guest

   - Svnapot support for KVM Guest

  s390:

   - New uvdevice secret API

   - CMM selftest and fixes

   - fix racy access to target CPU for diag 9c

  x86:

   - Fix missing/incorrect #GP checks on ENCLS

   - Use standard mmu_notifier hooks for handling APIC access page

   - Drop now unnecessary TR/TSS load after VM-Exit on AMD

   - Print more descriptive information about the status of SEV and
     SEV-ES during module load

   - Add a test for splitting and reconstituting hugepages during and
     after dirty logging

   - Add support for CPU pinning in demand paging test

   - Add support for AMD PerfMonV2, with a variety of cleanups and minor
     fixes included along the way

   - Add a "nx_huge_pages=never" option to effectively avoid creating NX
     hugepage recovery threads (because nx_huge_pages=off can be toggled
     at runtime)

   - Move handling of PAT out of MTRR code and dedup SVM+VMX code

   - Fix output of PIC poll command emulation when there's an interrupt

   - Add a maintainer's handbook to document KVM x86 processes,
     preferred coding style, testing expectations, etc.

   - Misc cleanups, fixes and comments

  Generic:

   - Miscellaneous bugfixes and cleanups

  Selftests:

   - Generate dependency files so that partial rebuilds work as
     expected"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (153 commits)
  Documentation/process: Add a maintainer handbook for KVM x86
  Documentation/process: Add a label for the tip tree handbook's coding style
  KVM: arm64: Fix misuse of KVM_ARM_VCPU_POWER_OFF bit index
  RISC-V: KVM: Remove unneeded semicolon
  RISC-V: KVM: Allow Svnapot extension for Guest/VM
  riscv: kvm: define vcpu_sbi_ext_pmu in header
  RISC-V: KVM: Expose IMSIC registers as attributes of AIA irqchip
  RISC-V: KVM: Add in-kernel virtualization of AIA IMSIC
  RISC-V: KVM: Expose APLIC registers as attributes of AIA irqchip
  RISC-V: KVM: Add in-kernel emulation of AIA APLIC
  RISC-V: KVM: Implement device interface for AIA irqchip
  RISC-V: KVM: Skeletal in-kernel AIA irqchip support
  RISC-V: KVM: Set kvm_riscv_aia_nr_hgei to zero
  RISC-V: KVM: Add APLIC related defines
  RISC-V: KVM: Add IMSIC related defines
  RISC-V: KVM: Implement guest external interrupt line management
  KVM: x86: Remove PRIx* definitions as they are solely for user space
  s390/uv: Update query for secret-UVCs
  s390/uv: replace scnprintf with sysfs_emit
  s390/uvdevice: Add 'Lock Secret Store' UVC
  ...

Add a label for the tip tree's "Coding style notes" so that a forthcoming
KVM x86 handbook can reference/piggyback the tip tree's preferred coding
style.

Link: https://lore.kernel.org/r/20230411171651.1067966-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Explain when tip branches get merged into mainline.

Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Christian Kujau <lists@nerdbynature.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/8a1fd8b7-9fe3-b2b5-406e-fa6f5e03e7c0@nerdbynature.de