Re: [PATCH v10 14/38] dyndbg: Bind callsites and classmaps to DDEBUG_MODNAME

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] dyndbg: overriding DDEBUG_MODNAME breaks loadable module classmaps
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commit c306ec85ef6e2f768827879da6cc3ed714ab0291
Author: Jim Cromie [off-list ref]
dyndbg: Bind callsites and classmaps to DDEBUG_MODNAME

This commit defines DDEBUG_MODNAME to allow subsystems to consolidate their
module names in dynamic debug by overriding it in their Makefiles. It binds
DDEBUG_MODNAME into the callsite and classmap declarator macros instead of
hardcoding KBUILD_MODNAME.

[ ... ]

[Severity: Medium]
Will this break loadable module classmaps if a subsystem opts into the
DDEBUG_MODNAME override?

When a module is loaded, the module loader assigns the physical module name
from the .ko filename to dt->mod_name in ddebug_module_notify(). However,
this macro embeds the overridden DDEBUG_MODNAME into cm->mod_name.

In lib/dynamic_debug.c:ddebug_attach_module_classes(), there is a strict
comparison between these two names:

    if (!strcmp(cm->mod_name, dt->mod_name)) {

If the DDEBUG_MODNAME differs from the physical module name, won't the
classmaps be silently discarded for loadable modules?

Also, won't queries against the consolidated module name fail because
ddebug_change() filters using the physical module name?

lib/dynamic_debug.c:ddebug_change() {
    ...
    if (query->module &&
        !match_wildcard(query->module, dt->mod_name))
            continue;
    ...
}

Subsequent patches in the series, such as the one introducing
dd_set_module_subrange(), appear to preserve this logic.

 		.base = _base,						\
 		.map_type = _maptype,					\
 		.class_names = _var##_classnames,			\

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Sashiko AI review · https://sashiko.dev/#/patchset/20260916-dd-cmap-part2-clean-v10-0-af4cf4767707@gmail.com?part=14