Re: [PATCH 0/3] btrfs-progs: updates related to seed device and v6.17 kernel

[Boris Burkov <boris@bur.io>]

On Mon, Aug 04, 2025 at 09:22:35AM +0930, Qu Wenruo wrote:
> Kernel commit 40426dd147ff ("btrfs: use the super_block as holder when
> mounting file systems") changed the block device holder so that each
> device of a mounted btrfs can only belong to a single fs.
> 
> This is fine for most users, but for a corner case of seed devices, it
> can be problematic.
> 
> As previously we allow the same seed device to be mounted through both
> the seed device and the sprouted fs, as at that time all btrfs devices
> share the same holder.
> 
> But now since each block device can only belong to a single mounted fs,
> it means the seed device can only be mounted through either the seed
> device itself or a sprouted fs, not both at the same time.
> 
> This series will update the docs to be more explicit about the seed
> device mounting behavior, and updated the test case misc/046 to follow
> the new kernel behavior.
> 
> And since we're here, also update a note where newer kernel fix a bug in
> orphan roots cleanup.

Looks good to me, thanks.
Reviewed-by: Boris Burkov <boris@bur.io>

> 
> 
> Qu Wenruo (3):
>   btrfs-progs: docs/seed: update a note related to orphan roots cleanup
>   btrfs-progs: docs/seed: add extra notes for v6.17 and newer kernels
>   btrfs-progs: misc-tests: do not try to mount a block device into
>     different filesystems
> 
>  Documentation/ch-seeding-device.rst           | 14 +++++++++++++-
>  tests/misc-tests/046-seed-multi-mount/test.sh | 17 ++++++++---------
>  2 files changed, 21 insertions(+), 10 deletions(-)
> 
> --
> 2.50.1
>