Adding CCs... On Wed, 30 Jan 2019, Joao Moreira wrote:
> From: Miroslav Benes <[email protected]> > > Currently, livepatch infrastructure in the kernel relies on > MODULE_INFO(livepatch, "Y") statement in a livepatch module. Then the > kernel module loader knows a module is indeed livepatch module and can > behave accordingly. > > klp-convert, on the other hand relies on LIVEPATCH_* statement in the > module's Makefile for exactly the same reason. > > Remove dependency on modinfo and generate MODULE_INFO flag > automatically in modpost when LIVEPATCH_* is defined in the module's > Makefile. Generate a list of all built livepatch modules based on > the .livepatch file and store it in (MODVERDIR)/livepatchmods. Give > this list as an argument for modpost which will use it to identify > livepatch modules. > > As MODULE_INFO is no longer needed, remove it. > > [jmoreira: > * fix modpost.c (add_livepatch_flag) to update module structure with > livepatch flag and prevent modpost from breaking due to unresolved > symbols] > > Signed-off-by: Miroslav Benes <[email protected]> > Signed-off-by: Joao Moreira <[email protected]> > --- > samples/livepatch/livepatch-sample.c | 1 - > scripts/Makefile.modpost | 8 +++- > scripts/mod/modpost.c | 84 > +++++++++++++++++++++++++++++++++--- > 3 files changed, 85 insertions(+), 8 deletions(-) > > diff --git a/samples/livepatch/livepatch-sample.c > b/samples/livepatch/livepatch-sample.c > index 2d554dd930e2..20a5891ebf7b 100644 > --- a/samples/livepatch/livepatch-sample.c > +++ b/samples/livepatch/livepatch-sample.c > @@ -90,4 +90,3 @@ static void livepatch_exit(void) > module_init(livepatch_init); > module_exit(livepatch_exit); > MODULE_LICENSE("GPL"); > -MODULE_INFO(livepatch, "Y"); Again, we shoud do the same for the other samples we have in samples/livepatch/ directory. > diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost > index da779a185218..0149a72ea7ae 100644 > --- a/scripts/Makefile.modpost > +++ b/scripts/Makefile.modpost > @@ -65,6 +65,11 @@ MODLISTCMD := find $(MODVERDIR) -name '*.mod' | xargs -r > grep -h '\.ko$$' | sort > __modules := $(shell $(MODLISTCMD)) > modules := $(patsubst %.o,%.ko, $(wildcard $(__modules:.ko=.o))) > > +# find all .livepatch files listed in $(MODVERDIR)/ > +ifdef CONFIG_LIVEPATCH > +$(shell find $(MODVERDIR) -name '*.livepatch' | xargs -r -I{} basename {} > .livepatch > $(MODVERDIR)/livepatchmods) > +endif > + > # Stop after building .o files if NOFINAL is set. Makes compile tests quicker > _modpost: $(if $(KBUILD_MODPOST_NOFINAL), $(modules:.ko:.o),$(modules)) > > @@ -79,7 +84,8 @@ modpost = scripts/mod/modpost \ > $(if $(KBUILD_EXTMOD),-o $(modulesymfile)) \ > $(if $(CONFIG_DEBUG_SECTION_MISMATCH),,-S) \ > $(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E) \ > - $(if $(KBUILD_EXTMOD)$(KBUILD_MODPOST_WARN),-w) > + $(if $(KBUILD_EXTMOD)$(KBUILD_MODPOST_WARN),-w) \ > + $(if $(CONFIG_LIVEPATCH),-l $(MODVERDIR)/livepatchmods) > > MODPOST_OPT=$(subst -i,-n,$(filter -i,$(MAKEFLAGS))) > > diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c > index 1dfc34d8b668..2fd1d409ca5a 100644 > --- a/scripts/mod/modpost.c > +++ b/scripts/mod/modpost.c > @@ -1979,10 +1979,6 @@ static void read_symbols(const char *modname) > license = get_next_modinfo(&info, "license", license); > } > > - /* Livepatch modules have unresolved symbols resolved by klp-convert */ > - if (get_modinfo(info.modinfo, info.modinfo_len, "livepatch")) > - mod->livepatch = 1; > - > for (sym = info.symtab_start; sym < info.symtab_stop; sym++) { > symname = remove_dot(info.strtab + sym->st_name); > > @@ -2421,6 +2417,76 @@ static void write_dump(const char *fname) > free(buf.p); > } > > +struct livepatch_mod_list { > + struct livepatch_mod_list *next; > + char *livepatch_mod; > +}; > + > +static struct livepatch_mod_list *load_livepatch_mods(const char *fname) > +{ > + struct livepatch_mod_list *list_iter, *list_start = NULL; > + unsigned long size, pos = 0; > + void *file = grab_file(fname, &size); > + char *line; > + > + if (!file) > + return NULL; > + > + while ((line = get_next_line(&pos, file, size))) { > + list_iter = NOFAIL(malloc(sizeof(*list_iter))); > + list_iter->next = list_start; > + list_iter->livepatch_mod = NOFAIL(strdup(line)); > + list_start = list_iter; > + } > + release_file(file, size); > + > + return list_start; > +} > + > +static void free_livepatch_mods(struct livepatch_mod_list *list_start) > +{ > + struct livepatch_mod_list *list_iter; > + > + while (list_start) { > + list_iter = list_start->next; > + free(list_start->livepatch_mod); > + free(list_start); > + list_start = list_iter; > + } > +} > + > +static int is_livepatch_mod(const char *modname, > + struct livepatch_mod_list *list) > +{ > + const char *myname; > + > + if (!list) > + return 0; > + > + myname = strrchr(modname, '/'); > + if (myname) > + myname++; > + else > + myname = modname; > + > + while (list) { > + if (!strcmp(myname, list->livepatch_mod)) > + return 1; > + list = list->next; > + } > + return 0; > +} > + > +static void add_livepatch_flag(struct buffer *b, struct module *mod, > + struct livepatch_mod_list *list) > +{ > + if (is_livepatch_mod(mod->name, list)) { > + buf_printf(b, "\nMODULE_INFO(livepatch, \"Y\");\n"); > + mod->livepatch = 1; > + } > +} > + > + > struct ext_sym_list { > struct ext_sym_list *next; > const char *file; > @@ -2436,8 +2502,9 @@ int main(int argc, char **argv) > int err; > struct ext_sym_list *extsym_iter; > struct ext_sym_list *extsym_start = NULL; > + struct livepatch_mod_list *livepatch_mods = NULL; > > - while ((opt = getopt(argc, argv, "i:I:e:mnsST:o:awE")) != -1) { > + while ((opt = getopt(argc, argv, "i:I:e:l:mnsST:o:awM:K:E")) != -1) { > switch (opt) { > case 'i': > kernel_read = optarg; > @@ -2454,6 +2521,9 @@ int main(int argc, char **argv) > extsym_iter->file = optarg; > extsym_start = extsym_iter; > break; > + case 'l': > + livepatch_mods = load_livepatch_mods(optarg); > + break; > case 'm': > modversions = 1; > break; > @@ -2514,15 +2584,16 @@ int main(int argc, char **argv) > buf.pos = 0; > > err |= check_modname_len(mod); > - err |= check_exports(mod); > add_header(&buf, mod); > add_intree_flag(&buf, !external_module); > add_retpoline(&buf); > add_staging_flag(&buf, mod->name); > + add_livepatch_flag(&buf, mod, livepatch_mods); > err |= add_versions(&buf, mod); > add_depends(&buf, mod); > add_moddevtable(&buf, mod); > add_srcversion(&buf, mod); > + err |= check_exports(mod); > > sprintf(fname, "%s.mod.c", mod->name); > write_if_changed(&buf, fname); > @@ -2541,6 +2612,7 @@ int main(int argc, char **argv) > "Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow > them.\n"); > } > } > + free_livepatch_mods(livepatch_mods); > free(buf.p); > > return err; > -- > 2.16.4 > Miroslav
