Userspace regression in LTS and stable kernels

[Samuel Dionne-Riel]

Hi,

I am posting as a representative of the NixOS Linux distribution,
about a userspace regression on 5.0-rc* which recently was backported
to the 4.14.99, 4.19.21 and 4.20.8 current LTS and stable versions.
The issue has been reported to the bug tracker, bug 202497, but seems
to have gone unnoticed by the maintainers.

The issue seems to break userspace for long-standing patterns in the
NixOS distribution, with regards to use of the shebangs.

Here is an example shebang causing an issue:

#! /nix/store/mbwav8kz8b3y471wjsybgzw84mrh4js9-perl-5.28.1/bin/perl
-I/nix/store/x6yyav38jgr924nkna62q3pkp0dgmzlx-perl5.28.1-File-Slurp-9999.25/lib/perl5/site_perl
-I/nix/store/ha8v67sl8dac92r9z07vzr4gv1y9nwqz-perl5.28.1-Net-DBus-1.1.0/lib/perl5/site_perl
-I/nix/store/dcrkvnjmwh69ljsvpbdjjdnqgwx90a9d-perl5.28.1-XML-Parser-2.44/lib/perl5/site_perl
-I/nix/store/rmji88k2zz7h4zg97385bygcydrf2q8h-perl5.28.1-XML-Twig-3.52/lib/perl5/site_perl

(The shebang was artificially wrapped spaces replaced by newlines)

Another contributor tracked the regression it to commit
8099b047ecc431518b9bb6bdbba3549bbecdc343 in the 5.0-rc* tree.

I bring no particular fix to the issue, but I believe it should at
least be fast-tracked to a revert for the stable and LTS branches, and
since 5.0 might drop soon, a solution worked on, or possibly a revert
until one is figured out.

Thanks,

-- 
â Samuel Dionne-Riel