Re: [PATCH v2 0/1] dm-crypt: allow encryption sector size up to PAGE_SIZE

[Milan Broz]

On 9/22/26 2:03 PM, Itai Handler wrote:
...> Exercised on arm64 with a 64K page granule: plain dm-crypt with
> sector_size 65536 over NVMe, block level round trip, fio random

Could you please point me to at least one consumer-grade NVMe drive that
supports a 64k sector size?

Allowing a bigger sector size in dm-crypt means you can end up with
partial dm-crypt sector writes (after power fail), which opens another
can of worms.

Your dm-verity argument does not apply here; it is a read-only target.

Also, arguments based on cryptsetup/LUKS2 do not make much sense for
kernel code. They must be compatible and work together, but dm-crypt
can be used without any userspace validation, so all limits must be
checked in the kernel.

LUKS2 limits the sector size to 4k for multiplatform compatibility.

dm-crypt itself can support bigger sectors, but I just do not see much
use for it with common NVMe drives or other storage.

Milan