On Tue, 29 Mar 2022, Marcelo Schmitt wrote: > Complement the Kernel Testing Guide documentation page by adding a > section about static analysis tools. > > Signed-off-by: Marcelo Schmitt <marcelo.schmitt1@xxxxxxxxx> > Acked-by: Daniel Latypov <dlatypov@xxxxxxxxxx> > Acked-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> > Reviewed-by: David Gow <davidgow@xxxxxxxxxx> > Reviewed-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx> Acked-by: Julia Lawall <julia.lawall@xxxxxxxx> > --- > Change log: > - Brought generic tool characteristics to the intro paragraph > - Made explicit that these tools run at compile time > - Added a note of caution about false positives > - Updated Coccinelle info to make it sound better and be more skimmable > > Documentation/dev-tools/testing-overview.rst | 31 ++++++++++++++++++++ > 1 file changed, 31 insertions(+) > > diff --git a/Documentation/dev-tools/testing-overview.rst b/Documentation/dev-tools/testing-overview.rst > index 65feb81edb14..b5e02dd3fd94 100644 > --- a/Documentation/dev-tools/testing-overview.rst > +++ b/Documentation/dev-tools/testing-overview.rst > @@ -115,3 +115,34 @@ that none of these errors are occurring during the test. > Some of these tools integrate with KUnit or kselftest and will > automatically fail tests if an issue is detected. > > +Static Analysis Tools > +===================== > + > +In addition to testing a running kernel, one can also analyze kernel source code > +directly (**at compile time**) using **static analysis** tools. The tools > +commonly used in the kernel allow one to inspect the whole source tree or just > +specific files within it. They make it easier to detect and fix problems during > +the development process. > + > +Sparse can help test the kernel by performing type-checking, lock checking, > +value range checking, in addition to reporting various errors and warnings while > +examining the code. See the Documentation/dev-tools/sparse.rst documentation > +page for details on how to use it. > + > +Smatch extends Sparse and provides additional checks for programming logic > +mistakes such as missing breaks in switch statements, unused return values on > +error checking, forgetting to set an error code in the return of an error path, > +etc. Smatch also has tests against more serious issues such as integer > +overflows, null pointer dereferences, and memory leaks. See the project page at > +http://smatch.sourceforge.net/. > + > +Coccinelle is another static analyzer at our disposal. Coccinelle is often used > +to aid refactoring and collateral evolution of source code, but it can also help > +to avoid certain bugs that occur in common code patterns. The types of tests > +available include API tests, tests for correct usage of kernel iterators, checks > +for the soundness of free operations, analysis of locking behavior, and further > +tests known to help keep consistent kernel usage. See the > +Documentation/dev-tools/coccinelle.rst documentation page for details. > + > +Beware, though, that static analysis tools suffer from **false positives**. > +Errors and warns need to be evaluated carefully before attempting to fix them. > -- > 2.35.1 > >
