Re: [PATCH] bpf: use FS_USERNS_DELEGATABLE for bpffs

[bot+bpf-ci]

> diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c
> index 005ea3a2c..c350857b2 100644

[ ... ]

> @@ -1077,7 +1073,7 @@ static struct file_system_type bpf_fs_type = {
>  	.init_fs_context = bpf_init_fs_context,
>  	.parameters	= bpf_fs_parameters,
>  	.kill_sb	= bpf_kill_super,
> -	.fs_flags	= FS_USERNS_MOUNT,
> +	.fs_flags	= FS_USERNS_DELEGATABLE,
>  };

FS_USERNS_DELEGATABLE does not appear to be defined anywhere in the kernel
tree. A search of include/linux/fs.h shows only FS_USERNS_MOUNT is defined
(at line 2268), not FS_USERNS_DELEGATABLE.

The commit message states this flag was "recently introduced", but it is not
present in this codebase. Will this cause a build failure due to an undefined
identifier?


---
AI reviewed your patch. Please fix the bug or email reply why it's not a bug.
See: https://github.com/kernel-patches/vmtest/blob/master/ci/claude/README.md

CI run summary: https://github.com/kernel-patches/bpf/actions/runs/21708956860

AI-authorship-score: low
AI-authorship-explanation: The commit follows standard kernel contribution patterns with natural language and proper references, suggesting human authorship, though the undefined flag error could indicate incomplete context.
issues-found: 1
issue-severity-score: high
issue-severity-explanation: The commit uses FS_USERNS_DELEGATABLE which is not defined in the kernel, causing a build failure that prevents kernel compilation.