Re: [PATCH] nilfs2: convert to use the new mount API

[Eric Sandeen <sandeen@redhat.com>]

On 4/4/24 8:21 PM, Eric Sandeen wrote:

> So the oops you hit is when a snapshot is mounted first, then the main
> fs is mounted.
> 
> My patch does this:
> 
>                         /*
>                          * Try remount to setup mount states if the current
>                          * tree is not mounted and only snapshots use this sb.
>                          */
>                         err = nilfs_reconfigure(fc);
> 
> (in place of nilfs_remount()), and nilfs_reconfigure expects to have
> fc->root set, which is normally only set up for an actual remount.
> 
> fc->root is NULL, so that's the oops. I'll see what I can work out.

Not sure if this is a terrible hack, but your test script passes with
this change on top of my original patch:

diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index 1cdc38db2612..4a9a8924068e 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -1232,6 +1232,7 @@ nilfs_get_tree(struct fs_context *fc)
 			 * Try remount to setup mount states if the current
 			 * tree is not mounted and only snapshots use this sb.
 			 */
+			fc->root = s->s_root;
 			err = nilfs_reconfigure(fc);
 			if (err)
 				goto failed_super;

-Eric