On Wed, Sep 29, 2021 at 02:24:22AM +0000, Naohiro Aota wrote:

On Mon, Sep 27, 2021 at 11:51:39PM +0200, David Sterba wrote:

quoted

On Mon, Sep 27, 2021 at 01:15:49PM +0900, Naohiro Aota wrote:
I was doing some btrfs-convert changes and found that it crashed, rough
bisection points to this series. With the last patch applied, convert
fails with the following ASAN error:

It looks like eb->fs_info == NULL at this point. In case of
btrfs-convert, we can assume it is non-zoned because we do not support
the converting on a zoned device (we can't create ext*, reiserfs on a
zoned device anyway).

That would mean that extN/reiserfs was created on a zoned device. One
can still do a image copy to a zoned device and then convert. Even if
this is possible in theory I'd rather not allow that right now because
there are probably more changes required to do full support.

I've just noticed that ZONED bit is mistakenly among the feature flag
bits allowed in convert. Added in 242c8328bcd55175 "btrfs-progs: zoned:
add new ZONED feature flag":

BTRFS_CONVERT_ALLOWED_FEATURES must not contain
BTRFS_FEATURE_INCOMPAT_ZONED.