On Sun, Jun 15, 2025 at 9:20 PM Kent Overstreet <kent.overstreet@xxxxxxxxx> wrote: > > On Mon, Jun 02, 2025 at 07:17:02PM +0200, Amir Goldstein wrote: > > Case folding is often applied to subtrees and not on an entire > > filesystem. > > > > Disallowing layers from filesystems that support case folding is over > > limiting. > > > > Replace the rule that case-folding capable are not allowed as layers > > with a rule that case folded directories are not allowed in a merged > > directory stack. > > > > Should case folding be enabled on an underlying directory while > > overlayfs is mounted the outcome is generally undefined. > > > > Specifically in ovl_lookup(), we check the base underlying directory > > and fail with -ESTALE and write a warning to kmsg if an underlying > > directory case folding is enabled. > > > > Suggested-by: Kent Overstreet <kent.overstreet@xxxxxxxxx> > > Link: https://lore.kernel.org/linux-fsdevel/20250520051600.1903319-1-kent.overstreet@xxxxxxxxx/ > > Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx> > > --- > > > > Miklos, > > > > This is my solution to Kent's request to allow overlayfs mount on > > bcachefs subtrees that do not have casefolding enabled, while other > > subtrees do have casefolding enabled. > > > > I have written a test to cover the change of behavior [1]. > > This test does not run on old kernel's where the mount always fails > > with casefold capable layers. > > > > Let me know what you think. > > > > Kent, > > > > I have tested this on ext4. > > Please test on bcachefs. > > Where are we at with getting this in? I've got users who keep asking, so > hoping we can get it backported to 6.15 I'm planning to queue this for 6.17, but hoping to get an ACK from Miklos first. Thanks, Amir.
