Re: [PATCH bpf v2] selftests/bpf: remove bash feature in test_xdp_redirect.sh

On 2/8/21 10:41 PM, Björn Töpel wrote:

On 2021-02-09 06:52, Andrii Nakryiko wrote:

quoted

On Sat, Feb 6, 2021 at 1:29 AM Björn Töpel [off-list ref] wrote:

quoted

From: Björn Töpel <redacted>

The test_xdp_redirect.sh script uses a bash redirect feature,
'&>/dev/null'. Use '>/dev/null 2>&1' instead.

We have plenty of explicit bash uses in selftest scripts, I'm not sure
it's a good idea to make scripts more verbose.

$ cd tools/testing/selftests
$ git grep '\#!/bin/bash'|wc -l
282
$ git grep '\#!/bin/sh'|wc -l
164

Andrii/Randy, I'm fine with whatever. I just want to be able to run the
test on Debian-derived systems. ;-)

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Also remove the 'set -e' since the script actually relies on that the
return value can be used to determine pass/fail of the test.

This sounds like a dubious decision. The script checks return results
only of last two commands, for which it's better to write and if
[<first command>] && [<second command>] check and leave set -e intact.

Ok!

Please decide on the shell flavor, and I'll respin a v3.

In general shell scripts in the kernel try not to use bash (we have taken
several patches to convert from /bin/bash to /bin/sh scripts).
OTOH, perf and bpf seem to be large exceptions to this trend,
so it is apparently OK to use bash. :)
Sorry to sidetrack you.

-- 
~Randy