Re: vfs.zfs.bclone_enabled (was: FreeBSD 14.0-BETA2 Now Available)

block_cloning feature is marked as READONLY_COMPAT.  It should not 
require any special handling from the boot code.

On 18.09.2023 07:22, Tomoaki AOKI wrote:
> Really OK?
> 
> I cannot find block_cloning in array *features_for_read[] of
> stand/libsa/zfs/zfsimpl.c, which possibly mean boot codes (including
> loader) cannot boot from Root-on-ZFS pool having block_cloning active.
> 
> Not sure adding '"com.fudosecurity:block_cloning",' here is sufficient
> or not. Possibly more works are needed.
> 
> IMHO, all default-enabled features should be safe for booting.
> Implement features with disalded, impement boot codes to support them,
> then finally enable them by default should be the only valid route.
> 
> 
> [1] https://cgit.freebsd.org/src/tree/stand/libsa/zfs/zfsimpl.c
> 
> 
> On Mon, 18 Sep 2023 07:31:46 +0200
> Martin Matuska <mm@FreeBSD.org> wrote:
> 
>> I vote for enabling block cloning on main :-)
>>
>> mm
>>
>> On 16. 9. 2023 19:14, Alexander Motin wrote:
>>> On 16.09.2023 01:25, Graham Perrin wrote:
>>>> On 16/09/2023 01:28, Glen Barber wrote:
>>>>> o A fix for the ZFS block_cloning feature has been implemented.
>>>>
>>>> Thanks
>>>>
>>>> I see
>>>> <https://github.com/openzfs/zfs/commit/5cc1876f14f90430b24f1ad2f231de936691940f>,
>>>> with
>>>> <https://github.com/freebsd/freebsd-src/commit/9dcf00aa404bb62052433c45aaa5475e2760f5ed>
>>>> in stable/14.
>>>>
>>>> As vfs.zfs.bclone_enabled is still 0 (at least, with 15.0-CURRENT
>>>> n265350-72d97e1dd9cc): should we assume that additional fixes, not
>>>> necessarily in time for 14.0-RELEASE, will be required before
>>>> vfs.zfs.bclone_enabled can default to 1?
>>>
>>> I am not aware of any block cloning issues now.  All this thread about
>>> bclone_enabled actually started after I asked why it is still
>>> disabled. Thanks to Mark Millard for spotting this issue I could fix,
>>> but now we are back at the point of re-enabling it again.  Since the
>>> tunable does not even exist anywhere outside of FreeBSD base tree, I'd
>>> propose to give this code another try here too.  I see no point to
>>> have it disabled at least in main unless somebody needs time to run
>>> some specific tests first.
> 

-- 
Alexander Motin