On 2021/04/19 18:29, Christoph Hellwig wrote: > On Fri, Apr 16, 2021 at 06:17:21PM +0200, David Sterba wrote: >> On Fri, Apr 16, 2021 at 12:05:27PM +0900, Damien Le Moal wrote: >>> From: Johannes Thumshirn <johannes.thumshirn@xxxxxxx> >>> >>> For zoned btrfs, zone append is mandatory to write to a sequential write >>> only zone, otherwise parallel writes to the same zone could result in >>> unaligned write errors. >>> >>> If a zoned block device does not support zone append (e.g. a dm-crypt >>> zoned device using a non-NULL IV cypher), fail to mount. >>> >>> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx> >>> Signed-off-by: Damien Le Moal <damien.lemoal@xxxxxxx> >> >> Added to misc-next, thanks. I'll queue it for 5.13, it's not an urgent >> fix for 5.12 release but i'll tag it as stable so it'll apear in 5.12.x >> later. > > Please don't. Zone append is a strict requirement for zoned devices, > no need to add cargo cult code like this everywhere. This is only to avoid someone from running zoned-btrfs on top of dm-crypt. Without this patch, mount will be OK and file data writes will also actually be OK. But all reads will miserably fail... I would rather have this patch in than deal with the "bug reports" about btrfs failing to read files. No ? Note that like you, I dislike having to add such code. But it was my oversight when I worked on getting dm-crypt to work on zoned drives. Zone append was overlooked at that time... My bad, really. -- Damien Le Moal Western Digital Research