svn commit: r349763 - in stable/12/sys: kern sys

[Hans Petter Selasky]

On 2019-07-05 17:49, John Baldwin wrote:
> How does this not break the module KBI?  You've removed epoch_*_KBI symbols used
> by existing modules, and you appear to have changed the size of the
> 'struct epoch_tracker' object that existing modules allocate on the stack and
> pass to functions in the kernel.  Bumping __FreeBSD_version is not sufficient
> cover to break the KBI of widely used interfaces in stable (while we don't
> enforce KBI for all parts of the kernel, locking primitives is one of the things
> we can't break).

Hi John,

I'm aware there is a KPI breakage, but there is no API or functionality 
breakage.

The epoch(9) API is a very new API and I don't expect it to be widely 
used for binary only modules. Do you have any examples otherwise?

man 9 epoch

clearly states:

NOTES
      The epoch kernel programming interface is under development and is
      subject to change.

epoch(9) is currently mostly used inside the kernel which has to be 
re-compiled.

If you think it is really important that epoch(9) will stay KBI 
compliant I'll do the work to fix that.

--HPS