Merge tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:

 - "panic: sys_info: Refactor and fix a potential issue" (Andy Shevchenko)
   fixes a build issue and does some cleanup in ib/sys_info.c

 - "Implement mul_u64_u64_div_u64_roundup()" (David Laight)
   enhances the 64-bit math code on behalf of a PWM driver and beefs up
   the test module for these library functions

 - "scripts/gdb/symbols: make BPF debug info available to GDB" (Ilya Leoshkevich)
   makes BPF symbol names, sizes, and line numbers available to the GDB
   debugger

 - "Enable hung_task and lockup cases to dump system info on demand" (Feng Tang)
   adds a sysctl which can be used to cause additional info dumping when
   the hung-task and lockup detectors fire

 - "lib/base64: add generic encoder/decoder, migrate users" (Kuan-Wei Chiu)
   adds a general base64 encoder/decoder to lib/ and migrates several
   users away from their private implementations

 - "rbree: inline rb_first() and rb_last()" (Eric Dumazet)
   makes TCP a little faster

 - "liveupdate: Rework KHO for in-kernel users" (Pasha Tatashin)
   reworks the KEXEC Handover interfaces in preparation for Live Update
   Orchestrator (LUO), and possibly for other future clients

 - "kho: simplify state machine and enable dynamic updates" (Pasha Tatashin)
   increases the flexibility of KEXEC Handover. Also preparation for LUO

 - "Live Update Orchestrator" (Pasha Tatashin)
   is a major new feature targeted at cloud environments. Quoting the
   cover letter:

      This series introduces the Live Update Orchestrator, a kernel
      subsystem designed to facilitate live kernel updates using a
      kexec-based reboot. This capability is critical for cloud
      environments, allowing hypervisors to be updated with minimal
      downtime for running virtual machines. LUO achieves this by
      preserving the state of selected resources, such as memory,
      devices and their dependencies, across the kernel transition.

      As a key feature, this series includes support for preserving
      memfd file descriptors, which allows critical in-memory data, such
      as guest RAM or any other large memory region, to be maintained in
      RAM across the kexec reboot.

   Mike Rappaport merits a mention here, for his extensive review and
   testing work.

 - "kexec: reorganize kexec and kdump sysfs" (Sourabh Jain)
   moves the kexec and kdump sysfs entries from /sys/kernel/ to
   /sys/kernel/kexec/ and adds back-compatibility symlinks which can
   hopefully be removed one day

 - "kho: fixes for vmalloc restoration" (Mike Rapoport)
   fixes a BUG which was being hit during KHO restoration of vmalloc()
   regions

* tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (139 commits)
  calibrate: update header inclusion
  Reinstate "resource: avoid unnecessary lookups in find_next_iomem_res()"
  vmcoreinfo: track and log recoverable hardware errors
  kho: fix restoring of contiguous ranges of order-0 pages
  kho: kho_restore_vmalloc: fix initialization of pages array
  MAINTAINERS: TPM DEVICE DRIVER: update the W-tag
  init: replace simple_strtoul with kstrtoul to improve lpj_setup
  KHO: fix boot failure due to kmemleak access to non-PRESENT pages
  Documentation/ABI: new kexec and kdump sysfs interface
  Documentation/ABI: mark old kexec sysfs deprecated
  kexec: move sysfs entries to /sys/kernel/kexec
  test_kho: always print restore status
  kho: free chunks using free_page() instead of kfree()
  selftests/liveupdate: add kexec test for multiple and empty sessions
  selftests/liveupdate: add simple kexec-based selftest for LUO
  selftests/liveupdate: add userspace API selftests
  docs: add documentation for memfd preservation via LUO
  mm: memfd_luo: allow preserving memfd
  liveupdate: luo_file: add private argument to store runtime state
  mm: shmem: export some functions to internal.h
  ...

1 files changed, 40 insertions, 23 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index c2654075377e..ba36939fda79 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -342,8 +342,7 @@ config DEBUG_INFO_COMPRESSED_ZLIB
 	depends on $(cc-option,-gz=zlib)
 	depends on $(ld-option,--compress-debug-sections=zlib)
 	help
-	  Compress the debug information using zlib.  Requires GCC 5.0+ or Clang
-	  5.0+, binutils 2.26+, and zlib.
+	  Compress the debug information using zlib.
 
 	  Users of dpkg-deb via debian/rules may find an increase in
 	  size of their debug .deb packages with this config set, due to the
@@ -493,23 +492,23 @@ config DEBUG_SECTION_MISMATCH
 	bool "Enable full Section mismatch analysis"
 	depends on CC_IS_GCC
 	help
-	  The section mismatch analysis checks if there are illegal
-	  references from one section to another section.
-	  During linktime or runtime, some sections are dropped;
-	  any use of code/data previously in these sections would
-	  most likely result in an oops.
-	  In the code, functions and variables are annotated with
-	  __init,, etc. (see the full list in include/linux/init.h),
-	  which results in the code/data being placed in specific sections.
+	  The section mismatch analysis checks if there are illegal references
+	  from one section to another. During linktime or runtime, some
+	  sections are dropped; any use of code/data previously in these
+	  sections would most likely result in an oops.
+
+	  In the code, functions and variables are annotated with __init,
+	  __initdata, and so on (see the full list in include/linux/init.h).
+	  This directs the toolchain to place code/data in specific sections.
+
 	  The section mismatch analysis is always performed after a full
-	  kernel build, and enabling this option causes the following
-	  additional step to occur:
-	  - Add the option -fno-inline-functions-called-once to gcc commands.
-	    When inlining a function annotated with __init in a non-init
-	    function, we would lose the section information and thus
-	    the analysis would not catch the illegal reference.
-	    This option tells gcc to inline less (but it does result in
-	    a larger kernel).
+	  kernel build, and enabling this option causes the option
+	  -fno-inline-functions-called-once to be added to gcc commands.
+
+	  However, when inlining a function annotated with __init in
+	  a non-init function, we would lose the section information and thus
+	  the analysis would not catch the illegal reference.  This option
+	  tells gcc to inline less (but it does result in a larger kernel).
 
 config SECTION_MISMATCH_WARN_ONLY
 	bool "Make section mismatch errors non-fatal"
@@ -1260,12 +1259,13 @@ config DEFAULT_HUNG_TASK_TIMEOUT
 	  Keeping the default should be fine in most cases.
 
 config BOOTPARAM_HUNG_TASK_PANIC
-	bool "Panic (Reboot) On Hung Tasks"
+	int "Number of hung tasks to trigger kernel panic"
 	depends on DETECT_HUNG_TASK
+	default 0
 	help
-	  Say Y here to enable the kernel to panic on "hung tasks",
-	  which are bugs that cause the kernel to leave a task stuck
-	  in uninterruptible "D" state.
+	  When set to a non-zero value, a kernel panic will be triggered
+	  if the number of hung tasks found during a single scan reaches
+	  this value.
 
 	  The panic can be used in combination with panic_timeout,
 	  to cause the system to reboot automatically after a
@@ -2817,8 +2817,25 @@ config CMDLINE_KUNIT_TEST
 
 	  If unsure, say N.
 
+config BASE64_KUNIT
+	tristate "KUnit test for base64 decoding and encoding" if !KUNIT_ALL_TESTS
+	depends on KUNIT
+	default KUNIT_ALL_TESTS
+	help
+	  This builds the base64 unit tests.
+
+	  The tests cover the encoding and decoding logic of Base64 functions
+	  in the kernel.
+	  In addition to correctness checks, simple performance benchmarks
+	  for both encoding and decoding are also included.
+
+	  For more information on KUnit and unit tests in general please refer
+	  to the KUnit documentation in Documentation/dev-tools/kunit/.
+
+	  If unsure, say N.
+
 config BITS_TEST
-	tristate "KUnit test for bits.h" if !KUNIT_ALL_TESTS
+	tristate "KUnit test for bit functions and macros" if !KUNIT_ALL_TESTS
 	depends on KUNIT
 	default KUNIT_ALL_TESTS
 	help