On 20/12/2025 03:48, Daniel Gomez wrote:
From: Daniel Gomez <[email protected]>The -EEXIST error code is reserved by the module loading infrastructure to indicate that a module is already loaded. When a module's init function returns -EEXIST, userspace tools like kmod interpret this as "module already loaded" and treat the operation as successful, returning 0 to the user even though the module initialization actually failed. This follows the precedent set by commit 54416fd76770 ("netfilter: conntrack: helper: Replace -EEXIST by -EBUSY") which fixed the same issue in nf_conntrack_helper_register(). This affects bpf_crypto_skcipher module. While the configuration required to build it as a module is unlikely in practice, it is technically possible, so fix it for correctness. Signed-off-by: Daniel Gomez <[email protected]> --- The error code -EEXIST is reserved by the kernel module loader to indicate that a module with the same name is already loaded. When a module's init function returns -EEXIST, kmod interprets this as "module already loaded" and reports success instead of failure [1]. The kernel module loader will include a safety net that provides -EEXIST to -EBUSY with a warning [2], and a documentation patch has been sent to prevent future occurrences [3]. These affected code paths were identified using a static analysis tool [4] that traces -EEXIST returns to module_init(). The tool was developed with AI assistance and all findings were manually validated. Link: https://lore.kernel.org/all/[email protected]/ [1] Link: https://lore.kernel.org/all/[email protected]/ [2] Link: https://lore.kernel.org/all/20251218-dev-module-init-eexists-modules-docs-v1-0-361569aa7...@samsung.com/ [3] Link: https://gitlab.com/-/snippets/4913469 [4]
Even though I'm not quite sure that we should care once the core module loader can adjust the error, the change looks ok to me: Acked-by: Vadim Fedorenko <[email protected]>
