Re: [PATCH] selftests/vm: fix va_128TBswitch.sh permissions

[Adam Sindelar <adam@wowsignal.io>]

On Fri, Jul 08, 2022 at 01:08:01PM -0700, Andrew Morton wrote:
> On Fri,  8 Jul 2022 11:06:46 +0200 Adam Sindelar <adam@wowsignal.io> wrote:
> 
> > Restores the +x bit to va_128TBswitch.sh, which got dropped from the
> > previous patch, somehow.
> > 
> > Fixes: 1afd01d43efc3 ("selftests/vm: Only run 128TBswitch with 5-level
> > paging")
> > 
> > Signed-off-by: Adam Sindelar <adam@wowsignal.io>
> > ---
> >  tools/testing/selftests/vm/va_128TBswitch.sh | 0
> >  1 file changed, 0 insertions(+), 0 deletions(-)
> >  mode change 100644 => 100755 tools/testing/selftests/vm/va_128TBswitch.sh
> > 
> > diff --git a/tools/testing/selftests/vm/va_128TBswitch.sh b/tools/testing/selftests/vm/va_128TBswitch.sh
> > old mode 100644
> > new mode 100755
> 
> Half of tools/testing/selftests/vm/*.sh don't have the x bit set. 
> They're invoked via `/bin/sh foo.sh', which is more robust.
> 
> Can we hunt down and fix the invoking code?  Might be as simple as
> 
> --- a/tools/testing/selftests/vm/run_vmtests.sh~a
> +++ a/tools/testing/selftests/vm/run_vmtests.sh
> @@ -144,7 +144,7 @@ run_test() {
>  		local sep=$(echo -n "$title" | tr "[:graph:][:space:]" -)
>  		printf "%s\n%s\n%s\n" "$sep" "$title" "$sep"
>  
> -		"$@"
> +		/bin/sh "$@"
>  		local ret=$?
>  		if [ $ret -eq 0 ]; then
>  			echo "[PASS]"
> _
> 

I think that would impose the choice of shell on the test scripts. About
half of them start with '#!/bin/sh' and the other half with
'#!/bin/bash'.

Maybe that's something we'd want to do anyway, but it seems like it
could have subtle and unintended side effects if the goal is to fix a
failing test.

(It would also invoke the ELF binaries through /bin/sh, but that
probably doesn't matter, since sh will I think exec right away.)