| Message ID | 20250125064619.8305-18-jim.cromie@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Fix CONFIG_DRM_USE_DYNAMIC_DEBUG=y | expand |
Le 25/01/2025 à 07:45, Jim Cromie a écrit : > Add __DYNDBG_CLASSMAP_CHECK to implement these arg-checks at compile: > 0 <= _base < 63 > class_names is not empty > class_names[0] is a string > (class_names.length + _base) < 63 > > These compile-time checks will prevent several misuses; 4 such > examples are added to test_dynamic_debug_submod.ko, and will fail > compilation if -DDD_MACRO_ARGCHECK is added to cflags. > > Signed-off-by: Jim Cromie <jim.cromie@gmail.com> > --- > - split static-asserts to __DYNDBG_CLASSMAP_CHECK > - move __DYNDBG_CLASSMAP_CHECK above kdoc for DYNDBG_CLASSMAP_DEFINE > silences kernel-doc warnings > --- > include/linux/dynamic_debug.h | 9 +++++++++ > lib/test_dynamic_debug.c | 11 +++++++++++ > 2 files changed, 20 insertions(+) > > diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h > index dc610a12b91c..2b0c943af330 100644 > --- a/include/linux/dynamic_debug.h > +++ b/include/linux/dynamic_debug.h > @@ -99,6 +99,14 @@ struct ddebug_class_map { > enum ddebug_class_map_type map_type; > }; > > +#define __DYNDBG_CLASSMAP_CHECK(_clnames, _base) \ > + static_assert(((_base) >= 0 && (_base) < _DPRINTK_CLASS_DFLT), \ > + "_base must be in 0..62"); \ > + static_assert(ARRAY_SIZE(_clnames) > 0, \ > + "classnames array size must be > 0"); \ > + static_assert((ARRAY_SIZE(_clnames) + (_base)) < _DPRINTK_CLASS_DFLT, \ > + "_base + classnames.length exceeds range") > + > /** > * DYNDBG_CLASSMAP_DEFINE - define debug classes used by a module. > * @_var: name of the classmap, exported for other modules coordinated use. > @@ -112,6 +120,7 @@ struct ddebug_class_map { > */ > #define DYNDBG_CLASSMAP_DEFINE(_var, _mapty, _base, ...) \ > static const char *_var##_classnames[] = { __VA_ARGS__ }; \ > + __DYNDBG_CLASSMAP_CHECK(_var##_classnames, (_base)); \ > extern struct ddebug_class_map _var; \ > struct ddebug_class_map __aligned(8) __used \ > __section("__dyndbg_classes") _var = { \ > diff --git a/lib/test_dynamic_debug.c b/lib/test_dynamic_debug.c > index 1838f62738c4..b1555b0a2bb1 100644 > --- a/lib/test_dynamic_debug.c > +++ b/lib/test_dynamic_debug.c > @@ -123,8 +123,19 @@ DYNDBG_CLASSMAP_PARAM(level_num, p); > DYNDBG_CLASSMAP_USE(map_disjoint_bits); > DYNDBG_CLASSMAP_USE(map_level_num); > > +#if defined(DD_MACRO_ARGCHECK) > +/* > + * Exersize compile-time arg-checks in DYNDBG_CLASSMAP_DEFINE. > + * These will break compilation. > + */ > +DYNDBG_CLASSMAP_DEFINE(fail_base_neg, 0, -1, "NEGATIVE_BASE_ARG"); > +DYNDBG_CLASSMAP_DEFINE(fail_base_big, 0, 100, "TOOBIG_BASE_ARG"); > +DYNDBG_CLASSMAP_DEFINE(fail_str_type, 0, 0, 1 /* not a string */); > +DYNDBG_CLASSMAP_DEFINE(fail_emptyclass, 0, 0 /* ,empty */); Hi Jim, This test is nice, but can we move it in the *_submod.c directly? They don't need anything from this file. Tested-by: Louis Chauvet <louis.chauvet@bootlin.com> Thanks, Louis Chauvet > #endif > > +#endif /* TEST_DYNAMIC_DEBUG_SUBMOD */ > + > /* stand-in for all pr_debug etc */ > #define prdbg(SYM) __pr_debug_cls(SYM, #SYM " msg\n") >
On Tue, Feb 25, 2025 at 7:17 AM Louis Chauvet <louis.chauvet@bootlin.com> wrote: > > > > Le 25/01/2025 à 07:45, Jim Cromie a écrit : > > Add __DYNDBG_CLASSMAP_CHECK to implement these arg-checks at compile: > > 0 <= _base < 63 > > class_names is not empty > > class_names[0] is a string > > (class_names.length + _base) < 63 > > > > These compile-time checks will prevent several misuses; 4 such > > examples are added to test_dynamic_debug_submod.ko, and will fail > > compilation if -DDD_MACRO_ARGCHECK is added to cflags. > > > > Signed-off-by: Jim Cromie <jim.cromie@gmail.com> > > --- > > - split static-asserts to __DYNDBG_CLASSMAP_CHECK > > - move __DYNDBG_CLASSMAP_CHECK above kdoc for DYNDBG_CLASSMAP_DEFINE > > silences kernel-doc warnings > > --- > > include/linux/dynamic_debug.h | 9 +++++++++ > > lib/test_dynamic_debug.c | 11 +++++++++++ > > 2 files changed, 20 insertions(+) > > > > diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h > > index dc610a12b91c..2b0c943af330 100644 > > --- a/include/linux/dynamic_debug.h > > +++ b/include/linux/dynamic_debug.h > > @@ -99,6 +99,14 @@ struct ddebug_class_map { > > enum ddebug_class_map_type map_type; > > }; > > > > +#define __DYNDBG_CLASSMAP_CHECK(_clnames, _base) \ > > + static_assert(((_base) >= 0 && (_base) < _DPRINTK_CLASS_DFLT), \ > > + "_base must be in 0..62"); \ > > + static_assert(ARRAY_SIZE(_clnames) > 0, \ > > + "classnames array size must be > 0"); \ > > + static_assert((ARRAY_SIZE(_clnames) + (_base)) < _DPRINTK_CLASS_DFLT, \ > > + "_base + classnames.length exceeds range") > > + > > /** > > * DYNDBG_CLASSMAP_DEFINE - define debug classes used by a module. > > * @_var: name of the classmap, exported for other modules coordinated use. > > @@ -112,6 +120,7 @@ struct ddebug_class_map { > > */ > > #define DYNDBG_CLASSMAP_DEFINE(_var, _mapty, _base, ...) \ > > static const char *_var##_classnames[] = { __VA_ARGS__ }; \ > > + __DYNDBG_CLASSMAP_CHECK(_var##_classnames, (_base)); \ > > extern struct ddebug_class_map _var; \ > > struct ddebug_class_map __aligned(8) __used \ > > __section("__dyndbg_classes") _var = { \ > > diff --git a/lib/test_dynamic_debug.c b/lib/test_dynamic_debug.c > > index 1838f62738c4..b1555b0a2bb1 100644 > > --- a/lib/test_dynamic_debug.c > > +++ b/lib/test_dynamic_debug.c > > @@ -123,8 +123,19 @@ DYNDBG_CLASSMAP_PARAM(level_num, p); > > DYNDBG_CLASSMAP_USE(map_disjoint_bits); > > DYNDBG_CLASSMAP_USE(map_level_num); > > > > +#if defined(DD_MACRO_ARGCHECK) > > +/* > > + * Exersize compile-time arg-checks in DYNDBG_CLASSMAP_DEFINE. > > + * These will break compilation. > > + */ > > +DYNDBG_CLASSMAP_DEFINE(fail_base_neg, 0, -1, "NEGATIVE_BASE_ARG"); > > +DYNDBG_CLASSMAP_DEFINE(fail_base_big, 0, 100, "TOOBIG_BASE_ARG"); > > +DYNDBG_CLASSMAP_DEFINE(fail_str_type, 0, 0, 1 /* not a string */); > > +DYNDBG_CLASSMAP_DEFINE(fail_emptyclass, 0, 0 /* ,empty */); > > Hi Jim, > > This test is nice, but can we move it in the *_submod.c directly? They > don't need anything from this file. > Hi Louis, Given my strong preference for continued / justified ifdeffery earlier, I will interpret this as move these corner-case tests into the submod-only branch. Im happy to do it, and I see the commit-msg says that specifically, but Im not sure what it will improve by moving it. I could fix the commit msg instead. these compile-time tests will break the build, so I dont think theyre much good as a CONFIG_ option for example. So making the breakage submodule specific isnt much of a reduction in blast radius, and it only opens the why-submod-only ? Any views or options ? (both welcomed) > Tested-by: Louis Chauvet <louis.chauvet@bootlin.com> ack! > Thanks, > Louis Chauvet > > > #endif > > > > +#endif /* TEST_DYNAMIC_DEBUG_SUBMOD */ > > + > > /* stand-in for all pr_debug etc */ > > #define prdbg(SYM) __pr_debug_cls(SYM, #SYM " msg\n") > > > > -- > Louis Chauvet, Bootlin > Embedded Linux and Kernel engineering > https://bootlin.com >
diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h index dc610a12b91c..2b0c943af330 100644 --- a/include/linux/dynamic_debug.h +++ b/include/linux/dynamic_debug.h @@ -99,6 +99,14 @@ struct ddebug_class_map { enum ddebug_class_map_type map_type; }; +#define __DYNDBG_CLASSMAP_CHECK(_clnames, _base) \ + static_assert(((_base) >= 0 && (_base) < _DPRINTK_CLASS_DFLT), \ + "_base must be in 0..62"); \ + static_assert(ARRAY_SIZE(_clnames) > 0, \ + "classnames array size must be > 0"); \ + static_assert((ARRAY_SIZE(_clnames) + (_base)) < _DPRINTK_CLASS_DFLT, \ + "_base + classnames.length exceeds range") + /** * DYNDBG_CLASSMAP_DEFINE - define debug classes used by a module. * @_var: name of the classmap, exported for other modules coordinated use. @@ -112,6 +120,7 @@ struct ddebug_class_map { */ #define DYNDBG_CLASSMAP_DEFINE(_var, _mapty, _base, ...) \ static const char *_var##_classnames[] = { __VA_ARGS__ }; \ + __DYNDBG_CLASSMAP_CHECK(_var##_classnames, (_base)); \ extern struct ddebug_class_map _var; \ struct ddebug_class_map __aligned(8) __used \ __section("__dyndbg_classes") _var = { \ diff --git a/lib/test_dynamic_debug.c b/lib/test_dynamic_debug.c index 1838f62738c4..b1555b0a2bb1 100644 --- a/lib/test_dynamic_debug.c +++ b/lib/test_dynamic_debug.c @@ -123,8 +123,19 @@ DYNDBG_CLASSMAP_PARAM(level_num, p); DYNDBG_CLASSMAP_USE(map_disjoint_bits); DYNDBG_CLASSMAP_USE(map_level_num); +#if defined(DD_MACRO_ARGCHECK) +/* + * Exersize compile-time arg-checks in DYNDBG_CLASSMAP_DEFINE. + * These will break compilation. + */ +DYNDBG_CLASSMAP_DEFINE(fail_base_neg, 0, -1, "NEGATIVE_BASE_ARG"); +DYNDBG_CLASSMAP_DEFINE(fail_base_big, 0, 100, "TOOBIG_BASE_ARG"); +DYNDBG_CLASSMAP_DEFINE(fail_str_type, 0, 0, 1 /* not a string */); +DYNDBG_CLASSMAP_DEFINE(fail_emptyclass, 0, 0 /* ,empty */); #endif +#endif /* TEST_DYNAMIC_DEBUG_SUBMOD */ + /* stand-in for all pr_debug etc */ #define prdbg(SYM) __pr_debug_cls(SYM, #SYM " msg\n")
Add __DYNDBG_CLASSMAP_CHECK to implement these arg-checks at compile: 0 <= _base < 63 class_names is not empty class_names[0] is a string (class_names.length + _base) < 63 These compile-time checks will prevent several misuses; 4 such examples are added to test_dynamic_debug_submod.ko, and will fail compilation if -DDD_MACRO_ARGCHECK is added to cflags. Signed-off-by: Jim Cromie <jim.cromie@gmail.com> --- - split static-asserts to __DYNDBG_CLASSMAP_CHECK - move __DYNDBG_CLASSMAP_CHECK above kdoc for DYNDBG_CLASSMAP_DEFINE silences kernel-doc warnings --- include/linux/dynamic_debug.h | 9 +++++++++ lib/test_dynamic_debug.c | 11 +++++++++++ 2 files changed, 20 insertions(+)