Re: [PATCH 4/7] scripts/leaking_addresses: add reporting

Tobin C. Harding
2017-11-09T00:51:51Z

On Wed, Nov 08, 2017 at 11:42:21AM +0100, Petr Mladek wrote:
> On Wed 2017-11-08 14:37:36, Tobin C. Harding wrote:
> > Currently script just dumps all results found. Potentially, this risks
> > loosing single results among multiple duplicate results. We need some
> > way of restricting duplicates to assist users of the script. It would
> > also be nice if we got a report instead of raw results.
> >
> > Duplicates can be defined in various ways, instead of trying to find a
> > single perfect solution we can present the user with various options to
> > display the output. Doing so will typically lead to users wanting to
> > view the output multiple times. Currently we scan the kernel each time,
> > this is slow and unnecessary. We can expedite the process by writing the
> > results to file for subsequent viewing.
> >
> > Add sub-commands `scan` and `format`. Display output as a report instead
> > of raw results. Add --raw flag to view raw results. Save results to
> > file. For subsequent calls to `format` parse output file instead of
> > re-scanning.
> >
> > Signed-off-by: Tobin C. Harding <me@tobin.cc>
> > ---
> > scripts/leaking_addresses.pl | 201 ++++++++++++++++++++++++++++++++++++++++---
> > 1 file changed, 187 insertions(+), 14 deletions(-)
> >
> > diff --git a/scripts/leaking_addresses.pl b/scripts/leaking_addresses.pl
> > index 719ed0aaede7..4c31e935319b 100755
> > --- a/scripts/leaking_addresses.pl
> > +++ b/scripts/leaking_addresses.pl
> > @@ -21,14 +21,19 @@ use File::Spec;
> > use Cwd 'abs_path';
> > use Term::ANSIColor qw(:constants);
> > use Getopt::Long qw(:config no_auto_abbrev);
> > +use File::Spec::Functions 'catfile';
> >
> > my $P = $0;
> > my $V = '0.01';
> >
> > -# Directories to scan.
> > +# Directories to scan (we scan `dmesg` also).
> > my @DIRS = ('/proc', '/sys');
> >
> > # Command line options.
> > +my $output = "scan.out";
>
> The hard-coded filename and its use is dangerous. Nobody expects that
> this kind of script writes/re-writes a file on the system.

Understood.

> > +my $suppress_dmesg = 0;
> > +my $squash_by_path = 0;
> > +my $raw = 0;
> > my $help = 0;
> > my $debug = 0;
> >
> > @@ -70,21 +75,34 @@ sub help
> > my ($exitcode) = @_;
> >
> > print << "EOM";
> > -Usage: $P [OPTIONS]
> > +
> > +Usage: $P COMMAND [OPTIONS]
> > Version: $V
> >
> > +Commands:
> > +
> > + scan Scan the kernel (savesg raw results to file and runs `format`).
> > + format Parse results file and format output.
>
> The later formatting/filtering might be useful but the use
> of the hard coded file is strange. Also it is pity that
> the script does not do anything useful out of box.
>
> I suggest to remove the commands and do the scan out of box.
> It should not store anything on the disk by default.
>
> Then we could define following options:
>
> -o, --output=<file> Store raw results into file for later formatting.
> -i, --input=<file> Read raw result from file and just format them.
>
> Well, it is still somehow non-intuitive. It might help to
> be more explicit:
>
> -o, --output-raw=<file>
> -i, --input-raw=<file>

So,

Usage: scripts/leaking_addresses.pl [OPTIONS]

Options:

-o, --output-raw=<file> Save results for future processing.
-i, --input-raw=<file> Read results from file instead of scanning.
--raw Show raw results (default).
--suppress-dmesg Do not show dmesg results.
--squash-by-path Show one result per unique path.
--squash-by-filename Show one result per unique filename.
-d, --debug Display debugging output.
-h, --help, --version Display this help and exit.

> > Options:
> >
> > - -d, --debug Display debugging output.
> > - -h, --help, --version Display this help and exit.
> > + -o, --output=<file> Raw results output file, used for later formatting.
> > + --suppress-dmesg Do not show dmesg results.
> > + --squash-by-path Show one result per unique path.
>
> I would personally add also option for the default mode:
>
> --squash-by-filename Show one result per unique filename
> (default).
>
> In fact, I would personally use --squash-by-path or even --raw by
> default. These provide easy to understand output. While the
> --squash-by-filename mode has pretty good results but
> it is quite non-intuitive.

Thanks for you suggestions Petr. Summary reporting by default was
suggested by Linus, but now the summary is implemented and has proven to
be heuristic I tend to agree with you that raw by default is
best. This gives users the information they need to select one of the
summary types i.e if raw output has a bunch of lines from different
paths but all filename FOO then --squash-by-filename may be used.

Thanks for the tips, it's much nicer without the sub-commands.

thanks,
Tobin.