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()
  ...

2 files changed, 45 insertions, 0 deletions

diff --git a/Documentation/driver-api/firmware/core.rst b/Documentation/driver-api/firmware/core.rst
index 1d1688cbc078..803cd574bbd7 100644
--- a/Documentation/driver-api/firmware/core.rst
+++ b/Documentation/driver-api/firmware/core.rst
@@ -13,4 +13,5 @@ documents these features.
    direct-fs-lookup
    fallback-mechanisms
    lookup-order
+   firmware-usage-guidelines
 
diff --git a/Documentation/driver-api/firmware/firmware-usage-guidelines.rst b/Documentation/driver-api/firmware/firmware-usage-guidelines.rst
new file mode 100644
index 000000000000..fdcfce42c6d2
--- /dev/null
+++ b/Documentation/driver-api/firmware/firmware-usage-guidelines.rst
@@ -0,0 +1,44 @@
+===================
+Firmware Guidelines
+===================
+
+Users switching to a newer kernel should *not* have to install newer
+firmware files to keep their hardware working. At the same time updated
+firmware files must not cause any regressions for users of older kernel
+releases.
+
+Drivers that use firmware from linux-firmware should follow the rules in
+this guide. (Where there is limited control of the firmware,
+i.e. company doesn't support Linux, firmwares sourced from misc places,
+then of course these rules will not apply strictly.)
+
+* Firmware files shall be designed in a way that it allows checking for
+  firmware ABI version changes. It is recommended that firmware files be
+  versioned with at least a major/minor version. It is suggested that
+  the firmware files in linux-firmware be named with some device
+  specific name, and just the major version. The firmware version should
+  be stored in the firmware header, or as an exception, as part of the
+  firmware file name, in order to let the driver detact any non-ABI
+  fixes/changes. The firmware files in linux-firmware should be
+  overwritten with the newest compatible major version. Newer major
+  version firmware shall remain compatible with all kernels that load
+  that major number.
+
+* If the kernel support for the hardware is normally inactive, or the
+  hardware isn't available for public consumption, this can
+  be ignored, until the first kernel release that enables that hardware.
+  This means no major version bumps without the kernel retaining
+  backwards compatibility for the older major versions.  Minor version
+  bumps should not introduce new features that newer kernels depend on
+  non-optionally.
+
+* If a security fix needs lockstep firmware and kernel fixes in order to
+  be successful, then all supported major versions in the linux-firmware
+  repo that are required by currently supported stable/LTS kernels,
+  should be updated with the security fix. The kernel patches should
+  detect if the firmware is new enough to declare if the security issue
+  is fixed.  All communications around security fixes should point at
+  both the firmware and kernel fixes. If a security fix requires
+  deprecating old major versions, then this should only be done as a
+  last option, and be stated clearly in all communications.
+