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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: Clear (ClamAV 1.4.3/27903/Thu Feb 5 08:23:30 2026) Hi Alexander, On 2/5/26 12:27 PM, Alexander Mikhalitsyn wrote: > Am Do., 5. Feb. 2026 um 12:20 Uhr schrieb : >> >>> 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? > > Yeah, this should be applied on top of > https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git/commit/?h=vfs-7.0.misc&id=269c46e936f3b5f2b6b567ca124d5f5ea07a371c > in vfs/vfs-7.0.misc I think. If this goes via Christian's vfs tree, it would make sense at least to open a test PR against https://github.com/kernel-patches/bpf to run this through the BPF CI with the vfs branch + your patch on top to make sure the tests don't break. Thanks, Daniel