Hi,

> > I tried to backport it to 5.10.x, but it failed to work.
> > No big modification in this 5.10.x backporting, and all modified pathes
> > are attached.
> 
> I'm not surprised, but I doubt there would be a major barrier to making
> it work.  I'm unlikely to try until I have more positive reviews.

With two patches as dependency, 
d045465fc6cbfa4acfb5a7d817a7c1a57a078109
	0001-exportfs-Add-a-function-to-return-the-raw-output-fro.patch
2e19d10c1438241de32467637a2a411971547991
	0002-nfsd-Fix-up-nfsd-to-ensure-that-timeout-errors-don-t.patch

the 5.10.x backporting become more simple and it works well now.

Best Regards
Wang Yugui (wangyugui@e16-tech.com)
2021/07/28