Re: [PATCH v3] erofs: accept source file descriptor via fsconfig

Gao Xiang <[email protected]> Fri, 17 Jul 2026 16:37:27 +0800
Newsgroups org.ozlabs.lists.linux-erofs,org.kernel.vger.linux-fsdevel
Message-ID <[email protected]>

On 2026/7/17 16:28, Giuseppe Scrivano wrote:
> Gao Xiang <[email protected]> writes:
> 
>> Hi Giuseppe,
>>
>> On 2026/7/14 23:48, Giuseppe Scrivano wrote:
>>> Allow userspace to pass an already-opened file descriptor as the mount
>>> source instead of a path string.  This is useful for tools that already
>>> hold an fd to the image, such as composefs reusing an existing erofs
>>> backing file.
>>> Signed-off-by: Giuseppe Scrivano <[email protected]>
>>
>> Use the current erofs-utils testsuite, the following tests seems skipped incorrectly.
>>
>> [Error 22] Invalid argument
>> SKIP: erofs/008
>> [Error 22] Invalid argument
>> SKIP: erofs/009
>> [Error 22] Invalid argument
>> SKIP: erofs/010
>> [Error 22] Invalid argument
>> SKIP: erofs/011
>>
>> [Error 22] Invalid argument
>> SKIP: erofs/017
>> [Error 22] Invalid argument
>> SKIP: erofs/018
>>
>> And the kernel message shows:
>> [  116.477816] erofs: source is unsupported
>> ...
>>
>> git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs-utils.git -b experimental-tests
>> $ sudo make check
>>
>> Thanks,
>> Gao Xiang
> 
> it seems to be caused by the different error returned by erofs_fc_get_tree.
> 
> Would you be fine if I amend this on top of v3?

I think you could just send out the diff from the baseline
since it might be harder to follow an incremental diff here.

But anyway, new versions are always welcome, I will play
with them when I am availble.

Thanks,
Gao Xiang

> 
> Thanks,
> Giuseppe