This series starts with 2 doc-only patches updating the current state of dynamic-debug, they were posted separately here, without pushback.
https://lore.kernel.org/linux-doc/[email protected]/ Next 5 are a fix to a linker-script alignment problem in 32bit arches causing a null-ptr scanning dyndbg-descriptor section on i386. These were reviewed by Petr Pavlu. The remaining patches are cleanups, refactors in preparation for an API change needed to fix a regression in DRM when it uses classmaps. I split these out for easier review, I will follow up with the API change afterwards. The biggest revision vs V2 is the new patch: 25. It addresses a flaw detected by sashiko which is best described by example. Dyndbg uses KBUILD_MODNAME to provide module-name, this works well for loadable modules (module loader requires unique module names), but for builtin modules, is effectively kbasename, and not unique. So we get 4 modules named "main": init/main, kernel/power/main, kernel/base/poser/main. This ambiguity is visible in user-space since the beginning of dyndbg. Now suppose kernel/{,base}/power/main want to define classmaps to categorize the various pr-debugs they have. The current code finds a module's classmaps by strcmp on modname, so init/main will match against classmaps defined by both kernel/{,base}/power/main. The current code will also map "main" classes to kernel/*/power/main, so they will probably work at first, but 2 independent classmaps can both use class-ids 0-N, but will conflict if they're both used by a module. Then we have classmap overlaps and unpredictable results. patch-25 eliminates the ambiguity by using KBUILD_MODFILE to provide a unique module-name, then adds matching against kbasename(modname) to restore the legacy query behavior. It *does* change the modname exposed in /proc/dynamic_debug/control, but not the result of a query like "module main +p". OLDER VERSIONS: V2 primarily revises: https://lore.kernel.org/lkml/[email protected]/ V2 addressed most of sashiko's feedback on V1: https://sashiko.dev/#/patchset/20260504-dd-cleanups-2-v1-0-6fdd24040642%40gmail.com It dropped the pr-fmt patch, as not reproducible, advanced the drop-NAMES patch to reduce subsequent churn, and fixed the classmaps PARAMs to u64 to avoid 32bit flags on 32bit arches For easy one-stop-shopping, V2 also included 2 smaller series: 1st fixes a section alignment problem, with Reviewed-by from Petr Pavlu https://lore.kernel.org/lkml/[email protected]/ Signed-off-by: Jim Cromie <[email protected]> Signed-off-by: Jim Cromie <[email protected]> --- Changes in v3: - EDITME: describe what is new in this series revision. - EDITME: use bulletpoints and terse descriptions. - Link to v2: https://lore.kernel.org/r/[email protected] --- Jim Cromie (24): docs/dyndbg: update examples \012 to \n docs/dyndbg: explain flags parse 1st vmlinux.lds.h: refactor BOUNDED_SECTION_* macros into bounded_sections.lds.h vmlinux.lds.h: drop unused HEADERED_SECTION* macros vmlinux.lds.h: Fix ALIGN(8) omission causing NULL ptr on i386 vmlinux.lds.h: remove redundant ALIGN(8) directives dyndbg.lds.S: fix lost dyndbg sections in modules dyndbg: factor ddebug_match_desc out from ddebug_change dyndbg: add stub macro for DECLARE_DYNDBG_CLASSMAP dyndbg: reword "class unknown," to "class:_UNKNOWN_" dyndbg-API: remove DD_CLASS_TYPE_(DISJOINT|LEVEL)_NAMES and code dyndbg: drop NUM_TYPE_ARGS dyndbg: reduce verbose/debug clutter dyndbg: refactor param_set_dyndbg_classes and below dyndbg: tighten fn-sig of ddebug_apply_class_bitmap dyndbg: replace classmap list with an array-slice dyndbg: macrofy a 2-index for-loop pattern dyndbg: Upgrade class param storage to u64 for 64-bit classmaps dyndbg,module: make proper substructs in _ddebug_info dyndbg: move mod_name down from struct ddebug_table to _ddebug_info dyndbg: hoist classmap-filter-by-modname up to ddebug_add_module selftests-dyndbg: add a dynamic_debug run_tests target dyndbg: change __dynamic_func_call_cls* macros into expressions dynamic_debug: use KBUILD_MODFILE for unique builtin module names Documentation/admin-guide/dynamic-debug-howto.rst | 55 ++- MAINTAINERS | 2 + drivers/gpu/drm/drm_print.c | 6 +- include/asm-generic/bounded_sections.lds.h | 32 ++ include/asm-generic/dyndbg.lds.h | 18 + include/asm-generic/vmlinux.lds.h | 68 +-- include/drm/drm_print.h | 2 +- include/linux/dynamic_debug.h | 133 +++--- kernel/module/main.c | 12 +- lib/dynamic_debug.c | 501 ++++++++++----------- lib/test_dynamic_debug.c | 30 +- scripts/module.lds.S | 2 + tools/testing/selftests/Makefile | 1 + tools/testing/selftests/dynamic_debug/Makefile | 9 + tools/testing/selftests/dynamic_debug/config | 8 + .../selftests/dynamic_debug/dyndbg_selftest.sh | 294 ++++++++++++ 16 files changed, 736 insertions(+), 437 deletions(-) --- base-commit: e43ffb69e0438cddd72aaa30898b4dc446f664f8 change-id: 20260521-dd-maint-2-76c542079420 Best regards, -- Jim Cromie <[email protected]>
