Re: [PATCH v2 1/4] erofs: add file-backed mount support

From: Gao Xiang
Date: Wed Oct 02 2024 - 07:30:50 EST




On 2024/10/2 14:12, Christian Brauner wrote:
On Mon, Sep 30, 2024 at 04:18:19PM GMT, Jan Kara wrote:

..


diff --git a/fs/erofs/Kconfig b/fs/erofs/Kconfig
index 7dcdce660cac..1428d0530e1c 100644
--- a/fs/erofs/Kconfig
+++ b/fs/erofs/Kconfig
@@ -74,6 +74,23 @@ config EROFS_FS_SECURITY

If you are not using a security module, say N.

+config EROFS_FS_BACKED_BY_FILE
+ bool "File-backed EROFS filesystem support"
+ depends on EROFS_FS
+ default y

I am a bit reluctant to have this default to y, without an ack from
the VFS maintainers.

Well, we generally let filesystems do whatever they decide to do unless it
is a affecting stability / security / maintainability of the whole system.
In this case I don't see anything that would be substantially different
than if we go through a loop device. So although the feature looks somewhat
unusual I don't see a reason to nack it or otherwise interfere with
whatever the fs maintainer wants to do. Are you concerned about a
particular problem?

I see no reason to nak it either.

Thanks all for taking time on writing down these!

Unfortunately, fanotify pre-content hooks was't landed in 6.12 cycle
(which I think will be used in a lot of scenarios)..

I do hope it could be landed in the next cycle so I could clean up
the codebase then.

Thanks,
Gao Xiang