Re: [PATCH v3] selftests/livepatch: introduce tests
From: Libor Pechacek
Date: Tue Apr 24 2018 - 13:35:22 EST
On Mon 23-04-18 10:43:17, Joe Lawrence wrote:
> On Fri, Apr 20, 2018 at 02:56:05PM +0200, Libor Pechacek wrote:
[...]
> > > +
> > > + # Wait for livepatch transition ...
> > > + local i=0
> > > + while [[ $(cat /sys/kernel/livepatch/"$mod"/transition) != "0" ]]; do
> > > + i=$((i+1))
> > > + if [[ $i -eq $MAX_RETRIES ]]; then
> > > + die "failed to complete transition for module $mod"
> >
> > FWIW, qa_test_klp tests dump blocking processes' stacks at this place for more
> > efficient information exchange between tester and developer.
> > (klp_dump_blocking_processes() in https://github.com/lpechacek/qa_test_klp,
> > file klp_tc_functions.sh)
> >
>
> ... If I read the klp_dump_blocking_processes() code correctly and
> understand your comment, you are suggesting that reading (any)
> /sys/kernel/livepatch/*/transition would be simpler? No module
> parameter needed as only one should ever be transitioning at a given
> time?
Exactly.
[...]
> > > +# modname - module name to unload
> > > +function disable_lp() {
> > > + local mod="$1"
> >
> > ^^^VVVV - mixed indentation with tabs and spaces. Intentional?
> > (same in set_pre_patch_ret and several other places)
> >
>
> Ahh, thanks for spotting that. checkpatch doesn't seem to complain
> about shell script indentation. Funny that shellcheck didn't either.
>
> > > +
> > > + echo "% echo 0 > /sys/kernel/livepatch/$mod/enabled" > /dev/kmsg
> > > + echo 0 > /sys/kernel/livepatch/"$mod"/enabled
> >
> > How about folding disable_lp functionality into module unload function? That
> > would save extra invocation of disable_lp in test scripts.
> >
>
> Maybe this is just a stylistic thing, but I preferred the test scripts
> to be rather explicit about what they are doing. Instead of a do-it-all
> test_it() call, I liked how part_a(), part_b(), part_c() spelled things
> out.
>
> In some instances, these functions were once combined, but I ran
> into a scenario where I needed only a part of that function because I
> was injecting an error. That experience lead me to keep the test "api"
> more RISC than CISC :)
Understood. Thanks for explanation.
[...]
> > > diff --git a/tools/testing/selftests/livepatch/test-callbacks.sh b/tools/testing/selftests/livepatch/test-callbacks.sh
> > > new file mode 100755
> > > index 000000000000..739d09bb3cff
> > > --- /dev/null
> > > +++ b/tools/testing/selftests/livepatch/test-callbacks.sh
> > > @@ -0,0 +1,607 @@
> > > +#!/bin/bash
> > > +# SPDX-License-Identifier: GPL-2.0
> > > +# Copyright (C) 2018 Joe Lawrence <joe.lawrence@xxxxxxxxxx>
> > > +
> > > +. functions.sh
> >
> > This assumes functions.sh is in $CWD.
> >
>
> Good point. In the past, I've used something like:
>
> SCRIPTDIR="$(readlink -f $(dirname $(type -p $0)))"
>
> but I notice that not many selftests do anything special at all:
>
> % grep '^\. ' $(find . tools/testing/selftests/ -name '*.sh')
> ...
>
> only the perf tests do, and they use ". $(dirname $0)/..." so I'll use
> that convention for these tests.
Indeed! I'm for following the crowd.
Thanks for putting the scripts together. Good job done!
Libor
--
Libor Pechacek
SUSE Labs