feat(libkernel): start runtime-loaded modules with their arguments on Linux

[hugodearaujo]

What

Depends on #846. This branch contains its two commits. Only the last commit, feat(libkernel): start runtime-loaded modules with their arguments on Linux, belongs to this PR.

#846 starts --module-dir modules from sceKernelLoadStartModule with the call's args/argp on Windows. On Linux, the host loader runs their DT_INIT at dlopen with zeroed arguments, so #846 throws there when start arguments are given. This PR does on Linux what #846 does on Windows, with the same table:

• Relinker, Linux writer. A module from --module-dir gets no DT_INIT, DT_INIT_ARRAY, DT_FINI or DT_FINI_ARRAY. Like the Windows .ginit section, it exports __aps5_guest_initialize: the initializer's address, the number of INIT_ARRAY slots, and each slot's address. The symbol is added to the module's dynamic symbol table and hash. Modules from sce_module/prx are written as before.
• libkernel. After dlopen, OpenModule looks up __aps5_guest_initialize. It takes the module's load bias from dl_iterate_phdr and calls the initializer once with (args, argp, nullptr). It stores the return value in *res, then runs the INIT_ARRAY slots. The table walk and the "only once per module" set are now shared with the Windows path, which keeps its behavior. The NotImplemented for start arguments on Linux is removed.
• TechnicalDebt. The feat(relinker): add --module-dir for modules loaded at run time #846 line now says both platforms start these modules once, from the first call that loads them, and never run their finalizers. Windows already skipped the finalizers.

Evidence: Hollow Knight: Silksong (PPSA12544) on Linux

Unity loads its plugins from /app0/Media/Plugins with sceKernelLoadStartModule, and PSN.prx is started with start arguments. All runs below are relinked with --module-dir Media/Plugins, on main d70b89989 + #1836 + #1431 (the title stops before the plugins without them) + #846:

• Without this PR: terminate ... what(): sceKernelLoadStartModule with start arguments not implemented.
• With this PR: PSN.prx starts. The next stop is in the title's bundled libSceNpCppWebApi: CppWebApi::Common::initialize() failed. ret = 0x80553504, then an uncaught Unity.PSN.PS5.PSNException with that code. Common::initialize maps flexible memory and passes it to the bundled libc's sceLibcMspaceCreate, which refuses the address on Linux. That is the address-window problem of fix(guest-arena): place guest address space in the PS5 window on Linux #861, not this change.
• With this PR and fix(guest-arena): place guest address space in the PS5 window on Linux #861: the title reaches its title menu (START GAME / OPTIONS / EXTRAS) and keeps running at about 60 fps with no error until I stopped it (100 s).

Tested

• Linux (Arch, GCC 16.2, Release, RX 9070 XT): ctest 464/464 on this branch.
  • guest_module_dir gains a Linux case. A --module-dir module with DT_INIT, DT_FINI and one INIT_ARRAY slot is written without those tags. It exports __aps5_guest_initialize as a 12-byte object holding (0x1000, 1, 0x2380). The same module under sce_module keeps its tags and has no such symbol. The test fails on feat(relinker): add --module-dir for modules loaded at run time #846 without this commit.
  • guest_dynamic_loader gains a Linux case with a host fixture module that exports the table. GuestLoadStartModule_nid_no_patch with 16 bytes of arguments must call its start function once with those args/argp, store its return value (7) in *res, and run the INIT_ARRAY slot once. Loading the module a second time must not run either again. The test aborts on feat(relinker): add --module-dir for modules loaded at run time #846 without this commit, on its NotImplemented.
• Windows (Server 2025 VM, WinLibs GCC 15.2, CI flags, no GPU, so Vulkan tests are skipped): 458/458.
• Silksong as above.

Checklist

• Based on current main; no other open PR implements the same functions
• One topic per PR; follow-ups go in a new PR
• No comments in code except technical debt
• Unimplemented paths throw (NotImplemented_nid_no_patch); silent stubs are listed in TechnicalDebt
• No notes, investigation .md files or images added to the repository (attach them to this PR)
• New third-party code is a submodule built from source
• Generic behaviour, not specific to one title
• Depends on: feat(relinker): add --module-dir for modules loaded at run time #846
• AI-assisted: yes

@merwie: you mentioned you can't build the Linux path. If you'd rather carry this in #846, take the commit and I'll close this one.

🤖 Generated with Claude Code

[github-actions]

Other open pull requests touch the same code. Merging one will break the other, or both implement the same thing. If this one builds on them, list them in Depends on.

Pull request	Conflicting files (lines on main)	Same exports	Same new files
#1102	core/libs/prx/libkernel/Module/src/Module.cpp L157-158, L162-163 core/relinker/elfpatcher/src/linux/LinuxGuestModuleWriter.cpp L57, L76-77
#1249	core/relinker/elfpatcher/src/linux/LinuxGuestModuleWriter.cpp L57-58
#1597	core/relinker/cli/src/CliArgs.cpp L59, L68 core/relinker/main.cpp L94 core/relinker/relinker/include/relinker/guest/GuestImage.hpp L58 core/relinker/relinker/src/guest/GuestModuleBuilder.cpp L34, L273
#2117	core/relinker/cli/src/CliArgs.cpp L66-70
#2119	core/relinker/cli/src/CliArgs.cpp L59, L68 core/relinker/main.cpp L94 core/relinker/relinker/include/relinker/guest/GuestImage.hpp L58 core/relinker/relinker/src/guest/GuestModuleBuilder.cpp L34
#2212		dlopen_nid_postfix	core/relinker/relinker/tests/test_guest_module_dir.py

[Kikoarl]

Tested on Linux (CachyOS x86_64, Intel RPL-S iGPU / Mesa 26.3.0-devel / Vulkan 1.4.363, GCC 16.2.1) at b076f0f2:

• Build: Built cleanly in RAM (/tmp/anyps5_build) with zero warnings/errors.
• Conventions: python3 tools/check_conventions.py --base origin/main --head HEAD -> PASS (0 errors).
• Verification: Verified deferred module startup with CLI arguments on Linux platform in DynamicLoader.cpp and GuestDynamicLoader.cpp.

LGTM!

[oneandonlydean]

Closing as a duplicate of #1102, which passes args/argp to runtime-loaded modules on Linux on current main without needing #846. If PPSA12544 still stops at module start once #1102 and #846 are both in, please reopen with that log line.