From 1d2ad084800edad81cdc955304272742b10721c7 Mon Sep 17 00:00:00 2001 From: Vasily Gorbik Date: Sun, 6 Mar 2022 20:56:07 +0100 Subject: s390/nospec: add an option to use thunk-extern Currently with -mindirect-branch=thunk and -mfunction-return=thunk compiler options expoline thunks are put into individual COMDAT group sections. s390 is the only architecture which has group sections and it has implications for kpatch and objtool tools support. Using -mindirect-branch=thunk-extern and -mfunction-return=thunk-extern is an alternative, which comes with a need to generate all required expoline thunks manually. Unfortunately modules area is too far away from the kernel image, and expolines from the kernel image cannon be used. But since all new distributions (except Debian) build kernels for machine generations newer than z10, where "exrl" instruction is available, that leaves only 16 expolines thunks possible. Provide an option to build the kernel with -mindirect-branch=thunk-extern and -mfunction-return=thunk-extern for z10 or newer. This also requires to postlink expoline thunks into all modules explicitly. Currently modules already contain most expolines anyhow. Unfortunately -mindirect-branch=thunk-extern and -mfunction-return=thunk-extern options support is broken in gcc <= 11.2. Additional compile test is required to verify proper gcc support. Acked-by: Ilya Leoshkevich Co-developed-by: Sumanth Korikkar Signed-off-by: Sumanth Korikkar Signed-off-by: Vasily Gorbik --- scripts/mod/modpost.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 6bfa33217914..dbc0aaf69e43 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -658,6 +658,11 @@ static int ignore_undef_symbol(struct elf_info *info, const char *symname) strstarts(symname, "_savevr_") || strcmp(symname, ".TOC.") == 0) return 1; + + if (info->hdr->e_machine == EM_S390) + /* Expoline thunks are linked on all kernel modules during final link of .ko */ + if (strstarts(symname, "__s390_indirect_jump_r")) + return 1; /* Do not ignore this symbol */ return 0; } -- cgit v1.2.3 From 4d94f910e79a349b00a4f8aab6f3ae87129d8c5a Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Tue, 8 Mar 2022 22:56:13 +0100 Subject: Kbuild: use -Wdeclaration-after-statement MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The kernel is moving from using `-std=gnu89` to `-std=gnu11`, permitting the use of additional C11 features such as for-loop initial declarations. One contentious aspect of C99 is that it permits mixed declarations and code, and for now at least, it seems preferable to enforce that declarations must come first. These warnings were already enabled in the kernel itself, but not for KBUILD_USERCFLAGS or the compat VDSO on arch/arm64, which uses a separate set of CFLAGS. This patch fixes an existing violation in modpost.c, which is not reported because of the missing flag in KBUILD_USERCFLAGS: | scripts/mod/modpost.c: In function ‘match’: | scripts/mod/modpost.c:837:3: warning: ISO C90 forbids mixed declarations and code [-Wdeclaration-after-statement] | 837 | const char *endp = p + strlen(p) - 1; | | ^~~~~ Signed-off-by: Mark Rutland [arnd: don't add a duplicate flag to the default set, update changelog] Signed-off-by: Arnd Bergmann Reviewed-by: Nathan Chancellor Reviewed-by: Nick Desaulniers Tested-by: Sedat Dilek # LLVM/Clang v13.0.0 (x86-64) Signed-off-by: Masahiro Yamada --- scripts/mod/modpost.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 6bfa33217914..fe693304b120 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -833,8 +833,10 @@ static int match(const char *sym, const char * const pat[]) { const char *p; while (*pat) { + const char *endp; + p = *pat++; - const char *endp = p + strlen(p) - 1; + endp = p + strlen(p) - 1; /* "*foo*" */ if (*p == '*' && *endp == '*') { -- cgit v1.2.3 From d31ed5d767c0452b4f49846d80a0bfeafa3a4ded Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Fri, 18 Mar 2022 12:19:27 +0100 Subject: kbuild: Fixup the IBT kbuild changes Masahiro-san deemed my kbuild changes to support whole module objtool runs too terrible to live and gracefully provided an alternative. Suggested-by: Masahiro Yamada Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/CAK7LNAQ2mYMnOKMQheVi+6byUFE3KEkjm1zcndNUfe0tORGvug@mail.gmail.com --- scripts/mod/modpost.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 6bfa33217914..09c3ab0a9b37 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1989,9 +1989,9 @@ static char *remove_dot(char *s) if (m && (s[n + m] == '.' || s[n + m] == 0)) s[n] = 0; - /* strip trailing .lto */ - if (strends(s, ".lto")) - s[strlen(s) - 4] = '\0'; + /* strip trailing .prelink */ + if (strends(s, ".prelink")) + s[strlen(s) - 8] = '\0'; } return s; } @@ -2015,9 +2015,9 @@ static void read_symbols(const char *modname) /* strip trailing .o */ tmp = NOFAIL(strdup(modname)); tmp[strlen(tmp) - 2] = '\0'; - /* strip trailing .lto */ - if (strends(tmp, ".lto")) - tmp[strlen(tmp) - 4] = '\0'; + /* strip trailing .prelink */ + if (strends(tmp, ".prelink")) + tmp[strlen(tmp) - 8] = '\0'; mod = new_module(tmp); free(tmp); } -- cgit v1.2.3 From bf5c0c2231bcab677e5cdfb7f73e6c79f6d8c2d4 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sat, 2 Apr 2022 00:56:10 +0900 Subject: modpost: restore the warning message for missing symbol versions This log message was accidentally chopped off. I was wondering why this happened, but checking the ML log, Mark precisely followed my suggestion [1]. I just used "..." because I was too lazy to type the sentence fully. Sorry for the confusion. [1]: https://lore.kernel.org/all/CAK7LNAR6bXXk9-ZzZYpTqzFqdYbQsZHmiWspu27rtsFxvfRuVA@mail.gmail.com/ Fixes: 4a6795933a89 ("kbuild: modpost: Explicitly warn about unprototyped symbols") Signed-off-by: Masahiro Yamada Acked-by: Mark Brown Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index d10f93aac1c8..ed9d056d2108 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -674,7 +674,7 @@ static void handle_modversion(const struct module *mod, unsigned int crc; if (sym->st_shndx == SHN_UNDEF) { - warn("EXPORT symbol \"%s\" [%s%s] version ...\n" + warn("EXPORT symbol \"%s\" [%s%s] version generation failed, symbol will not be versioned.\n" "Is \"%s\" prototyped in ?\n", symname, mod->name, mod->is_vmlinux ? "" : ".ko", symname); -- cgit v1.2.3 From c268c0a8a33047cd957fecc1349d09a68eb6ad9e Mon Sep 17 00:00:00 2001 From: Manivannan Sadhasivam Date: Tue, 5 Apr 2022 19:27:54 +0530 Subject: bus: mhi: ep: Add uevent support for module autoloading Add uevent support to MHI endpoint bus so that the client drivers can be autoloaded by udev when the MHI endpoint devices gets created. The client drivers are expected to provide MODULE_DEVICE_TABLE with the MHI id_table struct so that the alias can be exported. The MHI endpoint reused the mhi_device_id structure of the MHI bus. Reviewed-by: Alex Elder Signed-off-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/20220405135754.6622-19-manivannan.sadhasivam@linaro.org Signed-off-by: Greg Kroah-Hartman --- scripts/mod/file2alias.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'scripts/mod') diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c index 5258247d78ac..d9d6a31446ea 100644 --- a/scripts/mod/file2alias.c +++ b/scripts/mod/file2alias.c @@ -1391,6 +1391,15 @@ static int do_mhi_entry(const char *filename, void *symval, char *alias) return 1; } +/* Looks like: mhi_ep:S */ +static int do_mhi_ep_entry(const char *filename, void *symval, char *alias) +{ + DEF_FIELD_ADDR(symval, mhi_device_id, chan); + sprintf(alias, MHI_EP_DEVICE_MODALIAS_FMT, *chan); + + return 1; +} + /* Looks like: ishtp:{guid} */ static int do_ishtp_entry(const char *filename, void *symval, char *alias) { @@ -1519,6 +1528,7 @@ static const struct devtable devtable[] = { {"tee", SIZE_tee_client_device_id, do_tee_entry}, {"wmi", SIZE_wmi_device_id, do_wmi_entry}, {"mhi", SIZE_mhi_device_id, do_mhi_entry}, + {"mhi_ep", SIZE_mhi_device_id, do_mhi_ep_entry}, {"auxiliary", SIZE_auxiliary_device_id, do_auxiliary_entry}, {"ssam", SIZE_ssam_device_id, do_ssam_entry}, {"dfl", SIZE_dfl_device_id, do_dfl_entry}, -- cgit v1.2.3 From 7ce3e410e0188ce7ca65b49c90cff2863d6e232e Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 5 Apr 2022 20:33:51 +0900 Subject: modpost: remove useless export_from_sec() With commit 1743694eb235 ("modpost: stop symbol preloading for modversion CRC") applied, now export_from_sec() is useless. handle_symbol() is called for every symbol in the ELF. When 'symname' does not start with "__ksymtab", export_from_sec() is called, and the returned value is stored in 'export'. It is used in the last part of handle_symbol(): if (strstarts(symname, "__ksymtab_")) { name = symname + strlen("__ksymtab_"); sym_add_exported(name, mod, export); } 'export' is used only when 'symname' starts with "__ksymtab_". So, the value returned by export_from_sec() is never used. Remove useless export_from_sec(). This makes further cleanups possible. I put the temporary code: export = export_unknown; Otherwise, I would get the compiler warning: warning: 'export' may be used uninitialized in this function [-Wmaybe-uninitialized] This is apparently false positive because if (strstarts(symname, "__ksymtab_") ... is a stronger condition than: if (strstarts(symname, "__ksymtab") Anyway, this part will be cleaned up by the next commit. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 17 ++--------------- scripts/mod/modpost.h | 2 -- 2 files changed, 2 insertions(+), 17 deletions(-) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index ed9d056d2108..eebb32689816 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -369,16 +369,6 @@ static enum export export_from_secname(struct elf_info *elf, unsigned int sec) return export_unknown; } -static enum export export_from_sec(struct elf_info *elf, unsigned int sec) -{ - if (sec == elf->export_sec) - return export_plain; - else if (sec == elf->export_gpl_sec) - return export_gpl; - else - return export_unknown; -} - static const char *namespace_from_kstrtabns(const struct elf_info *info, const Elf_Sym *sym) { @@ -576,10 +566,7 @@ static int parse_elf(struct elf_info *info, const char *filename) fatal("%s has NOBITS .modinfo\n", filename); info->modinfo = (void *)hdr + sechdrs[i].sh_offset; info->modinfo_len = sechdrs[i].sh_size; - } else if (strcmp(secname, "__ksymtab") == 0) - info->export_sec = i; - else if (strcmp(secname, "__ksymtab_gpl") == 0) - info->export_gpl_sec = i; + } if (sechdrs[i].sh_type == SHT_SYMTAB) { unsigned int sh_link_idx; @@ -703,7 +690,7 @@ static void handle_symbol(struct module *mod, struct elf_info *info, if (strstarts(symname, "__ksymtab")) export = export_from_secname(info, get_secindex(info, sym)); else - export = export_from_sec(info, get_secindex(info, sym)); + export = export_unknown; switch (sym->st_shndx) { case SHN_COMMON: diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h index 0c47ff95c0e2..0a940fd2e5c7 100644 --- a/scripts/mod/modpost.h +++ b/scripts/mod/modpost.h @@ -138,8 +138,6 @@ struct elf_info { Elf_Shdr *sechdrs; Elf_Sym *symtab_start; Elf_Sym *symtab_stop; - Elf_Section export_sec; - Elf_Section export_gpl_sec; char *strtab; char *modinfo; unsigned int modinfo_len; -- cgit v1.2.3 From 535b3e05f435698f8f661d9e6449beb5791fff59 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 5 Apr 2022 20:33:52 +0900 Subject: modpost: move export_from_secname() call to more relevant place The assigned 'export' is only used when if (strstarts(symname, "__ksymtab_")) is met. The else-part of the assignment is the dead code. Move the export_from_secname() call to where it is used. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index eebb32689816..f9e54247ae1d 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -684,14 +684,8 @@ static void handle_modversion(const struct module *mod, static void handle_symbol(struct module *mod, struct elf_info *info, const Elf_Sym *sym, const char *symname) { - enum export export; const char *name; - if (strstarts(symname, "__ksymtab")) - export = export_from_secname(info, get_secindex(info, sym)); - else - export = export_unknown; - switch (sym->st_shndx) { case SHN_COMMON: if (strstarts(symname, "__gnu_lto_")) { @@ -726,7 +720,11 @@ static void handle_symbol(struct module *mod, struct elf_info *info, default: /* All exported symbols */ if (strstarts(symname, "__ksymtab_")) { + enum export export; + name = symname + strlen("__ksymtab_"); + export = export_from_secname(info, + get_secindex(info, sym)); sym_add_exported(name, mod, export); } if (strcmp(symname, "init_module") == 0) -- cgit v1.2.3 From b5f1a52a59eb810f68c96d1cea7cf1256c39956c Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 5 Apr 2022 20:33:53 +0900 Subject: modpost: remove redundant initializes for static variables These are initialized with zeros without explicit initializers. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index f9e54247ae1d..2a202764ff48 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -23,15 +23,15 @@ #include "../../include/linux/license.h" /* Are we using CONFIG_MODVERSIONS? */ -static int modversions = 0; +static int modversions; /* Is CONFIG_MODULE_SRCVERSION_ALL set? */ -static int all_versions = 0; +static int all_versions; /* If we are modposting external module set to 1 */ -static int external_module = 0; +static int external_module; /* Only warn about unresolved symbols */ -static int warn_unresolved = 0; +static int warn_unresolved; /* How a symbol is exported */ -static int sec_mismatch_count = 0; +static int sec_mismatch_count; static int sec_mismatch_warn_only = true; /* ignore missing files */ static int ignore_missing_files; -- cgit v1.2.3 From 79f646e8654b6b8e4f7dda456ec3eabd51052041 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 5 Apr 2022 20:33:54 +0900 Subject: modpost: remove annoying namespace_from_kstrtabns() There are two call sites for sym_update_namespace(). When the symbol has no namespace, s->namespace is set to NULL, but the conversion from "" to NULL is done in two different places. [1] read_symbols() This gets the namespace from __kstrtabns_. If the symbol has no namespace, sym_get_data(info, sym) returns the empty string "". namespace_from_kstrtabns() converts it to NULL before it is passed to sym_update_namespace(). [2] read_dump() This gets the namespace from the dump file, *.symvers. If the symbol has no namespace, the 'namespace' is the empty string "", which is directly passed into sym_update_namespace(). The conversion from "" to NULL is done in sym_update_namespace(). namespace_from_kstrtabns() exists only for creating this inconsistency. Remove namespace_from_kstrtabns() so that sym_update_namespace() is consistently passed with "" instead of NULL. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 14 ++------------ 1 file changed, 2 insertions(+), 12 deletions(-) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 2a202764ff48..522d5249d196 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -369,13 +369,6 @@ static enum export export_from_secname(struct elf_info *elf, unsigned int sec) return export_unknown; } -static const char *namespace_from_kstrtabns(const struct elf_info *info, - const Elf_Sym *sym) -{ - const char *value = sym_get_data(info, sym); - return value[0] ? value : NULL; -} - static void sym_update_namespace(const char *symname, const char *namespace) { struct symbol *s = find_symbol(symname); @@ -391,8 +384,7 @@ static void sym_update_namespace(const char *symname, const char *namespace) } free(s->namespace); - s->namespace = - namespace && namespace[0] ? NOFAIL(strdup(namespace)) : NULL; + s->namespace = namespace[0] ? NOFAIL(strdup(namespace)) : NULL; } /** @@ -2049,9 +2041,7 @@ static void read_symbols(const char *modname) /* Apply symbol namespaces from __kstrtabns_ entries. */ if (strstarts(symname, "__kstrtabns_")) sym_update_namespace(symname + strlen("__kstrtabns_"), - namespace_from_kstrtabns(&info, - sym)); - + sym_get_data(&info, sym)); if (strstarts(symname, "__crc_")) handle_modversion(mod, &info, sym, symname + strlen("__crc_")); -- cgit v1.2.3 From 9413e7640564fe70b24ea1a9ff3fb92c5bb52fcb Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 7 Apr 2022 00:30:20 +0900 Subject: kbuild: split the second line of *.mod into *.usyms The *.mod files have two lines; the first line lists the member objects of the module, and the second line, if CONFIG_TRIM_UNUSED_KSYMS=y, lists the undefined symbols. Currently, we generate *.mod after constructing composite modules, otherwise, we cannot compute the second line. No prerequisite is required to print the first line. They are orthogonal. Splitting them into separate commands will ease further cleanups. This commit splits the list of undefined symbols out to *.usyms files. Previously, the list of undefined symbols ended up with a very long line, but now it has one symbol per line. Use sed like we did before commit 7d32358be8ac ("kbuild: avoid split lines in .mod files"). Signed-off-by: Masahiro Yamada Reviewed-by: Nicolas Schier --- scripts/mod/sumversion.c | 11 ++--------- 1 file changed, 2 insertions(+), 9 deletions(-) (limited to 'scripts/mod') diff --git a/scripts/mod/sumversion.c b/scripts/mod/sumversion.c index 905c0ec291e1..0125698f2037 100644 --- a/scripts/mod/sumversion.c +++ b/scripts/mod/sumversion.c @@ -387,7 +387,7 @@ out_file: /* Calc and record src checksum. */ void get_src_version(const char *modname, char sum[], unsigned sumlen) { - char *buf, *pos, *firstline; + char *buf; struct md4_ctx md; char *fname; char filelist[PATH_MAX + 1]; @@ -397,15 +397,8 @@ void get_src_version(const char *modname, char sum[], unsigned sumlen) buf = read_text_file(filelist); - pos = buf; - firstline = get_line(&pos); - if (!firstline) { - warn("bad ending versions file for %s\n", modname); - goto free; - } - md4_init(&md); - while ((fname = strsep(&firstline, " "))) { + while ((fname = strsep(&buf, " \n"))) { if (!*fname) continue; if (!(is_static_library(fname)) && -- cgit v1.2.3 From 22f26f21774f838e97921952d8c5c4aab3da2ea4 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 7 Apr 2022 00:30:21 +0900 Subject: kbuild: get rid of duplication in *.mod files It is allowed to add the same objects multiple times to obj-y / obj-m: obj-y += foo.o foo.o foo.o obj-m += bar.o bar.o bar.o It is also allowed to add the same objects multiple times to a composite module: obj-m += foo.o foo-y := foo1.o foo2.o foo2.o foo1.o This flexibility is useful because the same object might be selected by different CONFIG options, like this: obj-m += foo.o foo-y := foo1.o foo-$(CONFIG_FOO_X) += foo2.o foo-$(CONFIG_FOO_Y) += foo2.o The duplicated objects are omitted at link time. It works naturally in Makefiles because GNU Make removes duplication in $^ without changing the order. It is working well, almost... A small flaw I notice is, *.mod contains duplication in such a case. This is probably not a big deal. As far as I know, the only small problem is scripts/mod/sumversion.c parses the same file multiple times. I am fixing this because I plan to reuse *.mod for other purposes, where the duplication can be problematic. The code change is quite simple. We already use awk to drop duplicated lines in modules.order (see cmd_modules_order in the same file). I copied the code, but changed RS to use spaces as record separators. I also changed the file format to list one object per line. Signed-off-by: Masahiro Yamada --- scripts/mod/sumversion.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/mod') diff --git a/scripts/mod/sumversion.c b/scripts/mod/sumversion.c index 0125698f2037..79bb9eaa65ac 100644 --- a/scripts/mod/sumversion.c +++ b/scripts/mod/sumversion.c @@ -398,7 +398,7 @@ void get_src_version(const char *modname, char sum[], unsigned sumlen) buf = read_text_file(filelist); md4_init(&md); - while ((fname = strsep(&buf, " \n"))) { + while ((fname = strsep(&buf, "\n"))) { if (!*fname) continue; if (!(is_static_library(fname)) && -- cgit v1.2.3 From 15a28c7c72917f96820e9e9ccd113606363ba3ac Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 25 Apr 2022 04:07:45 +0900 Subject: modpost: use snprintf() instead of sprintf() for safety Use snprintf() to avoid the potential buffer overflow, and also check the return value to detect the too long path. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 522d5249d196..141370ebbfd3 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -2560,6 +2560,7 @@ int main(int argc, char **argv) for (mod = modules; mod; mod = mod->next) { char fname[PATH_MAX]; + int ret; if (mod->is_vmlinux || mod->from_dump) continue; @@ -2578,7 +2579,12 @@ int main(int argc, char **argv) add_moddevtable(&buf, mod); add_srcversion(&buf, mod); - sprintf(fname, "%s.mod.c", mod->name); + ret = snprintf(fname, sizeof(fname), "%s.mod.c", mod->name); + if (ret >= sizeof(fname)) { + error("%s: too long path was truncated\n", fname); + continue; + } + write_if_changed(&buf, fname); } -- cgit v1.2.3 From c155a47d83ab0b5ee96ebe1721057cba1936d0d5 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 25 Apr 2022 04:07:46 +0900 Subject: modpost: do not write out any file when error occurred If an error occurs, modpost will fail anyway. Do not write out any content (, which might be invalid). Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 141370ebbfd3..f0d48f65fb33 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -2333,6 +2333,9 @@ static void write_buf(struct buffer *b, const char *fname) { FILE *file; + if (error_occurred) + return; + file = fopen(fname, "w"); if (!file) { perror(fname); -- cgit v1.2.3 From 594ade3eef3f2d458902ced2cb2614dfae8558de Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 25 Apr 2022 04:07:47 +0900 Subject: modpost: remove stale comment about sym_add_exported() The description, it may have already been added without a CRC, in this case just update the CRC ... is no longer valid. In the old days, this function was used to update the CRC as well. Commit 040fcc819a2e ("kbuild: improved modversioning support for external modules") started to use a separate function (sym_update_crc) for updating the CRC. The first part, "Add an exported symbol" is correct, but it is too obvious from the function name. Drop this comment entirely. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 4 ---- 1 file changed, 4 deletions(-) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index f0d48f65fb33..c7cfeeb088f7 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -387,10 +387,6 @@ static void sym_update_namespace(const char *symname, const char *namespace) s->namespace = namespace[0] ? NOFAIL(strdup(namespace)) : NULL; } -/** - * Add an exported symbol - it may have already been added without a - * CRC, in this case just update the CRC - **/ static struct symbol *sym_add_exported(const char *name, struct module *mod, enum export export) { -- cgit v1.2.3 From 23beb44a0effaad1bd627fd134f0301c622deba7 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 25 Apr 2022 04:07:48 +0900 Subject: modpost: add a separate error for exported symbols without definition It took me a while to understand the intent of "exp->module == mod". This code goes back to 2003. [1] The commit is not in this git repository, and might be worth a little explanation. You can add EXPORT_SYMBOL() without having its definition in the same file (but you need to put a declaration). This is typical when EXPORT_SYMBOL() is added in a C file, but the actual implementation is in a separate assembly file. One example is arch/arm/kernel/armksyms.c In the old days, EXPORT_SYMBOL() was only available in C files (but this limitation does not exist any more). If you forget to add the definition, this error occurs. Add a separate, clearer message for this case. It should be an error even if KBUILD_MODPOST_WARN is given. [1]: https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/commit/?id=2763b6bcb96e6a38a2fe31108fe5759ec5bcc80a Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index c7cfeeb088f7..969a081dba62 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -2147,13 +2147,18 @@ static void check_exports(struct module *mod) for (s = mod->unres; s; s = s->next) { const char *basename; exp = find_symbol(s->name); - if (!exp || exp->module == mod) { + if (!exp) { if (!s->weak && nr_unresolved++ < MAX_UNRESOLVED_REPORTS) modpost_log(warn_unresolved ? LOG_WARN : LOG_ERROR, "\"%s\" [%s.ko] undefined!\n", s->name, mod->name); continue; } + if (exp->module == mod) { + error("\"%s\" [%s.ko] was exported without definition\n", + s->name, mod->name); + continue; + } basename = strrchr(mod->name, '/'); if (basename) basename++; -- cgit v1.2.3 From 4cae77ac582b430d6ad6fbf0e1b23248997ceac8 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 25 Apr 2022 04:07:49 +0900 Subject: modpost: retrieve the module dependency and CRCs in check_exports() Do not repeat the similar code. It is simpler to do this in check_exports() instead of add_versions(). Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 969a081dba62..f9cbb6b6b7a5 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -2159,6 +2159,11 @@ static void check_exports(struct module *mod) s->name, mod->name); continue; } + + s->module = exp->module; + s->crc_valid = exp->crc_valid; + s->crc = exp->crc; + basename = strrchr(mod->name, '/'); if (basename) basename++; @@ -2251,16 +2256,7 @@ static void add_staging_flag(struct buffer *b, const char *name) **/ static void add_versions(struct buffer *b, struct module *mod) { - struct symbol *s, *exp; - - for (s = mod->unres; s; s = s->next) { - exp = find_symbol(s->name); - if (!exp || exp->module == mod) - continue; - s->module = exp->module; - s->crc_valid = exp->crc_valid; - s->crc = exp->crc; - } + struct symbol *s; if (!modversions) return; -- cgit v1.2.3 From 70ddb48db4aaddd3c2a7d8802463e15b21ce8525 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 25 Apr 2022 04:07:56 +0900 Subject: modpost: move struct namespace_list to modpost.c There is no good reason to define struct namespace_list in modpost.h struct module has pointers to struct namespace_list, but that does not require the definition of struct namespace_list. Move it to modpost.c. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 5 +++++ scripts/mod/modpost.h | 5 ----- 2 files changed, 5 insertions(+), 5 deletions(-) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index f9cbb6b6b7a5..689a34229809 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -270,6 +270,11 @@ static struct symbol *find_symbol(const char *name) return NULL; } +struct namespace_list { + struct namespace_list *next; + char namespace[]; +}; + static bool contains_namespace(struct namespace_list *list, const char *namespace) { diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h index 0a940fd2e5c7..7aed57fe793e 100644 --- a/scripts/mod/modpost.h +++ b/scripts/mod/modpost.h @@ -109,11 +109,6 @@ buf_printf(struct buffer *buf, const char *fmt, ...); void buf_write(struct buffer *buf, const char *s, int len); -struct namespace_list { - struct namespace_list *next; - char namespace[]; -}; - struct module { struct module *next; int gpl_compatible; -- cgit v1.2.3 From 58e01fcae18c9d01be701bec9e9a8ee58269c7c1 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 1 May 2022 17:40:07 +0900 Subject: modpost: use bool type where appropriate Use 'bool' to clarify that the valid value is true or false. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 56 ++++++++++++++++++++++++------------------------ scripts/mod/modpost.h | 11 +++++----- scripts/mod/sumversion.c | 8 +++---- 3 files changed, 37 insertions(+), 38 deletions(-) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 689a34229809..a6035ab78cd8 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -23,20 +23,20 @@ #include "../../include/linux/license.h" /* Are we using CONFIG_MODVERSIONS? */ -static int modversions; +static bool modversions; /* Is CONFIG_MODULE_SRCVERSION_ALL set? */ -static int all_versions; +static bool all_versions; /* If we are modposting external module set to 1 */ -static int external_module; +static bool external_module; /* Only warn about unresolved symbols */ -static int warn_unresolved; +static bool warn_unresolved; /* How a symbol is exported */ static int sec_mismatch_count; -static int sec_mismatch_warn_only = true; +static bool sec_mismatch_warn_only = true; /* ignore missing files */ -static int ignore_missing_files; +static bool ignore_missing_files; /* If set to 1, only warn (instead of error) about missing ns imports */ -static int allow_missing_ns_imports; +static bool allow_missing_ns_imports; static bool error_occurred; @@ -202,11 +202,11 @@ static struct module *new_module(const char *modname) struct symbol { struct symbol *next; struct module *module; - unsigned int crc; - int crc_valid; char *namespace; - unsigned int weak:1; - unsigned int is_static:1; /* 1 if symbol is not global */ + unsigned int crc; + bool crc_valid; + bool weak; + bool is_static; /* true if symbol is not global */ enum export export; /* Type of export */ char name[]; }; @@ -230,7 +230,7 @@ static inline unsigned int tdb_hash(const char *name) * Allocate a new symbols for use in the hash of exported symbols or * the list of unresolved symbols per module **/ -static struct symbol *alloc_symbol(const char *name, unsigned int weak, +static struct symbol *alloc_symbol(const char *name, bool weak, struct symbol *next) { struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1)); @@ -239,7 +239,7 @@ static struct symbol *alloc_symbol(const char *name, unsigned int weak, strcpy(s->name, name); s->weak = weak; s->next = next; - s->is_static = 1; + s->is_static = true; return s; } @@ -250,7 +250,7 @@ static struct symbol *new_symbol(const char *name, struct module *module, unsigned int hash; hash = tdb_hash(name) % SYMBOL_HASH_SIZE; - symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]); + symbolhash[hash] = alloc_symbol(name, false, symbolhash[hash]); return symbolhash[hash]; } @@ -424,7 +424,7 @@ static void sym_set_crc(const char *name, unsigned int crc) return; s->crc = crc; - s->crc_valid = 1; + s->crc_valid = true; } static void *grab_file(const char *filename, size_t *size) @@ -721,9 +721,9 @@ static void handle_symbol(struct module *mod, struct elf_info *info, sym_add_exported(name, mod, export); } if (strcmp(symname, "init_module") == 0) - mod->has_init = 1; + mod->has_init = true; if (strcmp(symname, "cleanup_module") == 0) - mod->has_cleanup = 1; + mod->has_cleanup = true; break; } } @@ -2058,7 +2058,7 @@ static void read_symbols(const char *modname) sym->st_name)); if (s) - s->is_static = 0; + s->is_static = false; } } @@ -2078,7 +2078,7 @@ static void read_symbols(const char *modname) * the automatic versioning doesn't pick it up, but it's really * important anyhow */ if (modversions) - mod->unres = alloc_symbol("module_layout", 0, mod->unres); + mod->unres = alloc_symbol("module_layout", false, mod->unres); } static void read_symbols_from_files(const char *filename) @@ -2310,7 +2310,7 @@ static void add_depends(struct buffer *b, struct module *mod) if (s->module->seen) continue; - s->module->seen = 1; + s->module->seen = true; p = strrchr(s->module->name, '/'); if (p) p++; @@ -2427,10 +2427,10 @@ static void read_dump(const char *fname) mod = find_module(modname); if (!mod) { mod = new_module(modname); - mod->from_dump = 1; + mod->from_dump = true; } s = sym_add_exported(symname, mod, export_no(export)); - s->is_static = 0; + s->is_static = false; sym_set_crc(symname, crc); sym_update_namespace(symname, namespace); } @@ -2508,7 +2508,7 @@ int main(int argc, char **argv) while ((opt = getopt(argc, argv, "ei:mnT:o:awENd:")) != -1) { switch (opt) { case 'e': - external_module = 1; + external_module = true; break; case 'i': *dump_read_iter = @@ -2517,28 +2517,28 @@ int main(int argc, char **argv) dump_read_iter = &(*dump_read_iter)->next; break; case 'm': - modversions = 1; + modversions = true; break; case 'n': - ignore_missing_files = 1; + ignore_missing_files = true; break; case 'o': dump_write = optarg; break; case 'a': - all_versions = 1; + all_versions = true; break; case 'T': files_source = optarg; break; case 'w': - warn_unresolved = 1; + warn_unresolved = true; break; case 'E': sec_mismatch_warn_only = false; break; case 'N': - allow_missing_ns_imports = 1; + allow_missing_ns_imports = true; break; case 'd': missing_namespace_deps = optarg; diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h index 7aed57fe793e..0bd8f697f94c 100644 --- a/scripts/mod/modpost.h +++ b/scripts/mod/modpost.h @@ -1,4 +1,5 @@ /* SPDX-License-Identifier: GPL-2.0 */ +#include #include #include #include @@ -113,11 +114,11 @@ struct module { struct module *next; int gpl_compatible; struct symbol *unres; - int from_dump; /* 1 if module was loaded from *.symvers */ - int is_vmlinux; - int seen; - int has_init; - int has_cleanup; + bool from_dump; /* true if module was loaded from *.symvers */ + bool is_vmlinux; + bool seen; + bool has_init; + bool has_cleanup; struct buffer dev_table_buf; char srcversion[25]; // Missing namespace dependencies diff --git a/scripts/mod/sumversion.c b/scripts/mod/sumversion.c index 79bb9eaa65ac..6bf9caca0968 100644 --- a/scripts/mod/sumversion.c +++ b/scripts/mod/sumversion.c @@ -290,13 +290,11 @@ static int parse_file(const char *fname, struct md4_ctx *md) return 1; } /* Check whether the file is a static library or not */ -static int is_static_library(const char *objfile) +static bool is_static_library(const char *objfile) { int len = strlen(objfile); - if (objfile[len - 2] == '.' && objfile[len - 1] == 'a') - return 1; - else - return 0; + + return objfile[len - 2] == '.' && objfile[len - 1] == 'a'; } /* We have dir/file.o. Open dir/.file.o.cmd, look for source_ and deps_ line -- cgit v1.2.3 From 5066743e4c2f702c1da8ba00a1dc217527a0ab7c Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 1 May 2022 17:40:08 +0900 Subject: modpost: change mod->gpl_compatible to bool type Currently, mod->gpl_compatible is tristate; it is set to -1 by default, then to 1 or 0 when MODULE_LICENSE() is found. Maybe, -1 was chosen to represent the 'unknown' license, but it is not useful. The current code: if (!mod->gpl_compatible) check_for_gpl_usage(exp->export, basename, exp->name); ... only cares whether gpl_compatible is zero or not. Change it to a bool type with the initial value 'true', which has no functional change. The default value should be 'true' instead of 'false'. Since commit 1d6cd3929360 ("modpost: turn missing MODULE_LICENSE() into error"), unknown module license is an error. The error message, "missing MODULE_LICENSE()" is enough to explain the issue. It is not sensible to show another message, "GPL-incompatible module ... uses GPL-only symbol". Add comments to explain this. While I was here, I renamed gpl_compatible to is_gpl_compatible for clarification, and also slightly refactored the code. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 17 +++++++++++------ scripts/mod/modpost.h | 2 +- 2 files changed, 12 insertions(+), 7 deletions(-) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index a6035ab78cd8..25066dc25790 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -187,7 +187,14 @@ static struct module *new_module(const char *modname) /* add to list */ strcpy(mod->name, modname); mod->is_vmlinux = (strcmp(modname, "vmlinux") == 0); - mod->gpl_compatible = -1; + + /* + * Set mod->is_gpl_compatible to true by default. If MODULE_LICENSE() + * is missing, do not check the use for EXPORT_SYMBOL_GPL() becasue + * modpost will exit wiht error anyway. + */ + mod->is_gpl_compatible = true; + mod->next = modules; modules = mod; @@ -2012,10 +2019,8 @@ static void read_symbols(const char *modname) if (!license) error("missing MODULE_LICENSE() in %s\n", modname); while (license) { - if (license_is_gpl_compatible(license)) - mod->gpl_compatible = 1; - else { - mod->gpl_compatible = 0; + if (!license_is_gpl_compatible(license)) { + mod->is_gpl_compatible = false; break; } license = get_next_modinfo(&info, "license", license); @@ -2183,7 +2188,7 @@ static void check_exports(struct module *mod) add_namespace(&mod->missing_namespaces, exp->namespace); } - if (!mod->gpl_compatible) + if (!mod->is_gpl_compatible) check_for_gpl_usage(exp->export, basename, exp->name); } } diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h index 0bd8f697f94c..73c36dfbf0e1 100644 --- a/scripts/mod/modpost.h +++ b/scripts/mod/modpost.h @@ -112,7 +112,7 @@ buf_write(struct buffer *buf, const char *s, int len); struct module { struct module *next; - int gpl_compatible; + bool is_gpl_compatible; struct symbol *unres; bool from_dump; /* true if module was loaded from *.symvers */ bool is_vmlinux; -- cgit v1.2.3 From 97aa4aef532aed6885e887ad6979e5ffb2667c84 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 1 May 2022 17:40:09 +0900 Subject: modpost: import include/linux/list.h Import include/linux/list.h to use convenient list macros in modpost. I dropped kernel-space code such as {WRITE,READ}_ONCE etc. and unneeded macros. I also imported container_of() from include/linux/container_of.h and type definitions from include/linux/types.h. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/list.h | 213 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 213 insertions(+) create mode 100644 scripts/mod/list.h (limited to 'scripts/mod') diff --git a/scripts/mod/list.h b/scripts/mod/list.h new file mode 100644 index 000000000000..a924a6c4aa4d --- /dev/null +++ b/scripts/mod/list.h @@ -0,0 +1,213 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef LIST_H +#define LIST_H + +#include +#include + +/* Are two types/vars the same type (ignoring qualifiers)? */ +#define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b)) + +/** + * container_of - cast a member of a structure out to the containing structure + * @ptr: the pointer to the member. + * @type: the type of the container struct this is embedded in. + * @member: the name of the member within the struct. + * + */ +#define container_of(ptr, type, member) ({ \ + void *__mptr = (void *)(ptr); \ + _Static_assert(__same_type(*(ptr), ((type *)0)->member) || \ + __same_type(*(ptr), void), \ + "pointer type mismatch in container_of()"); \ + ((type *)(__mptr - offsetof(type, member))); }) + +#define LIST_POISON1 ((void *) 0x100) +#define LIST_POISON2 ((void *) 0x122) + +/* + * Circular doubly linked list implementation. + * + * Some of the internal functions ("__xxx") are useful when + * manipulating whole lists rather than single entries, as + * sometimes we already know the next/prev entries and we can + * generate better code by using them directly rather than + * using the generic single-entry routines. + */ + +struct list_head { + struct list_head *next, *prev; +}; + +#define LIST_HEAD_INIT(name) { &(name), &(name) } + +#define LIST_HEAD(name) \ + struct list_head name = LIST_HEAD_INIT(name) + +/** + * INIT_LIST_HEAD - Initialize a list_head structure + * @list: list_head structure to be initialized. + * + * Initializes the list_head to point to itself. If it is a list header, + * the result is an empty list. + */ +static inline void INIT_LIST_HEAD(struct list_head *list) +{ + list->next = list; + list->prev = list; +} + +/* + * Insert a new entry between two known consecutive entries. + * + * This is only for internal list manipulation where we know + * the prev/next entries already! + */ +static inline void __list_add(struct list_head *new, + struct list_head *prev, + struct list_head *next) +{ + next->prev = new; + new->next = next; + new->prev = prev; + prev->next = new; +} + +/** + * list_add - add a new entry + * @new: new entry to be added + * @head: list head to add it after + * + * Insert a new entry after the specified head. + * This is good for implementing stacks. + */ +static inline void list_add(struct list_head *new, struct list_head *head) +{ + __list_add(new, head, head->next); +} + +/** + * list_add_tail - add a new entry + * @new: new entry to be added + * @head: list head to add it before + * + * Insert a new entry before the specified head. + * This is useful for implementing queues. + */ +static inline void list_add_tail(struct list_head *new, struct list_head *head) +{ + __list_add(new, head->prev, head); +} + +/* + * Delete a list entry by making the prev/next entries + * point to each other. + * + * This is only for internal list manipulation where we know + * the prev/next entries already! + */ +static inline void __list_del(struct list_head *prev, struct list_head *next) +{ + next->prev = prev; + prev->next = next; +} + +static inline void __list_del_entry(struct list_head *entry) +{ + __list_del(entry->prev, entry->next); +} + +/** + * list_del - deletes entry from list. + * @entry: the element to delete from the list. + * Note: list_empty() on entry does not return true after this, the entry is + * in an undefined state. + */ +static inline void list_del(struct list_head *entry) +{ + __list_del_entry(entry); + entry->next = LIST_POISON1; + entry->prev = LIST_POISON2; +} + +/** + * list_is_head - tests whether @list is the list @head + * @list: the entry to test + * @head: the head of the list + */ +static inline int list_is_head(const struct list_head *list, const struct list_head *head) +{ + return list == head; +} + +/** + * list_empty - tests whether a list is empty + * @head: the list to test. + */ +static inline int list_empty(const struct list_head *head) +{ + return head->next == head; +} + +/** + * list_entry - get the struct for this entry + * @ptr: the &struct list_head pointer. + * @type: the type of the struct this is embedded in. + * @member: the name of the list_head within the struct. + */ +#define list_entry(ptr, type, member) \ + container_of(ptr, type, member) + +/** + * list_first_entry - get the first element from a list + * @ptr: the list head to take the element from. + * @type: the type of the struct this is embedded in. + * @member: the name of the list_head within the struct. + * + * Note, that list is expected to be not empty. + */ +#define list_first_entry(ptr, type, member) \ + list_entry((ptr)->next, type, member) + +/** + * list_next_entry - get the next element in list + * @pos: the type * to cursor + * @member: the name of the list_head within the struct. + */ +#define list_next_entry(pos, member) \ + list_entry((pos)->member.next, typeof(*(pos)), member) + +/** + * list_entry_is_head - test if the entry points to the head of the list + * @pos: the type * to cursor + * @head: the head for your list. + * @member: the name of the list_head within the struct. + */ +#define list_entry_is_head(pos, head, member) \ + (&pos->member == (head)) + +/** + * list_for_each_entry - iterate over list of given type + * @pos: the type * to use as a loop cursor. + * @head: the head for your list. + * @member: the name of the list_head within the struct. + */ +#define list_for_each_entry(pos, head, member) \ + for (pos = list_first_entry(head, typeof(*pos), member); \ + !list_entry_is_head(pos, head, member); \ + pos = list_next_entry(pos, member)) + +/** + * list_for_each_entry_safe - iterate over list of given type. Safe against removal of list entry + * @pos: the type * to use as a loop cursor. + * @n: another type * to use as temporary storage + * @head: the head for your list. + * @member: the name of the list_head within the struct. + */ +#define list_for_each_entry_safe(pos, n, head, member) \ + for (pos = list_first_entry(head, typeof(*pos), member), \ + n = list_next_entry(pos, member); \ + !list_entry_is_head(pos, head, member); \ + pos = n, n = list_next_entry(n, member)) + +#endif /* LIST_H */ -- cgit v1.2.3 From 325eba05e8ab53a9182a2734f0986c15e5f87349 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 1 May 2022 17:40:10 +0900 Subject: modpost: traverse modules in order Currently, modpost manages modules in a singly linked list; it adds a new node to the head, and traverses the list from new to old. It works, but the error messages are shown in the reverse order. If you have a Makefile like this: obj-m += foo.o bar.o then, modpost shows error messages in bar.o, foo.o, in this order. Use a doubly linked list to keep the order in modules.order; use list_add_tail() for the node addition and list_for_each_entry() for the list traverse. Now that the kernel's list macros have been imported to modpost, I will use them actively going forward. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 17 ++++++++--------- scripts/mod/modpost.h | 3 ++- 2 files changed, 10 insertions(+), 10 deletions(-) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 25066dc25790..1b9dcb44621c 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -165,16 +165,17 @@ char *get_line(char **stringp) } /* A list of all modules we processed */ -static struct module *modules; +LIST_HEAD(modules); static struct module *find_module(const char *modname) { struct module *mod; - for (mod = modules; mod; mod = mod->next) + list_for_each_entry(mod, &modules, list) { if (strcmp(mod->name, modname) == 0) - break; - return mod; + return mod; + } + return NULL; } static struct module *new_module(const char *modname) @@ -184,7 +185,6 @@ static struct module *new_module(const char *modname) mod = NOFAIL(malloc(sizeof(*mod) + strlen(modname) + 1)); memset(mod, 0, sizeof(*mod)); - /* add to list */ strcpy(mod->name, modname); mod->is_vmlinux = (strcmp(modname, "vmlinux") == 0); @@ -195,8 +195,7 @@ static struct module *new_module(const char *modname) */ mod->is_gpl_compatible = true; - mod->next = modules; - modules = mod; + list_add_tail(&mod->list, &modules); return mod; } @@ -2477,7 +2476,7 @@ static void write_namespace_deps_files(const char *fname) struct namespace_list *ns; struct buffer ns_deps_buf = {}; - for (mod = modules; mod; mod = mod->next) { + list_for_each_entry(mod, &modules, list) { if (mod->from_dump || !mod->missing_namespaces) continue; @@ -2568,7 +2567,7 @@ int main(int argc, char **argv) if (files_source) read_symbols_from_files(files_source); - for (mod = modules; mod; mod = mod->next) { + list_for_each_entry(mod, &modules, list) { char fname[PATH_MAX]; int ret; diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h index 73c36dfbf0e1..69601f36d080 100644 --- a/scripts/mod/modpost.h +++ b/scripts/mod/modpost.h @@ -11,6 +11,7 @@ #include #include +#include "list.h" #include "elfconfig.h" /* On BSD-alike OSes elf.h defines these according to host's word size */ @@ -111,7 +112,7 @@ void buf_write(struct buffer *buf, const char *s, int len); struct module { - struct module *next; + struct list_head list; bool is_gpl_compatible; struct symbol *unres; bool from_dump; /* true if module was loaded from *.symvers */ -- cgit v1.2.3 From e882e89bcf1d54da2e4388570325774c3e3078a9 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 1 May 2022 17:40:11 +0900 Subject: modpost: add sym_add_unresolved() helper Add a small helper, sym_add_unresolved() to ease the further refactoring. Remove the 'weak' argument from alloc_symbol() because it is sensible only for unresolved symbols. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 1b9dcb44621c..59d817692893 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -236,14 +236,12 @@ static inline unsigned int tdb_hash(const char *name) * Allocate a new symbols for use in the hash of exported symbols or * the list of unresolved symbols per module **/ -static struct symbol *alloc_symbol(const char *name, bool weak, - struct symbol *next) +static struct symbol *alloc_symbol(const char *name, struct symbol *next) { struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1)); memset(s, 0, sizeof(*s)); strcpy(s->name, name); - s->weak = weak; s->next = next; s->is_static = true; return s; @@ -256,11 +254,17 @@ static struct symbol *new_symbol(const char *name, struct module *module, unsigned int hash; hash = tdb_hash(name) % SYMBOL_HASH_SIZE; - symbolhash[hash] = alloc_symbol(name, false, symbolhash[hash]); + symbolhash[hash] = alloc_symbol(name, symbolhash[hash]); return symbolhash[hash]; } +static void sym_add_unresolved(const char *name, struct module *mod, bool weak) +{ + mod->unres = alloc_symbol(name, mod->unres); + mod->unres->weak = weak; +} + static struct symbol *find_symbol(const char *name) { struct symbol *s; @@ -712,9 +716,8 @@ static void handle_symbol(struct module *mod, struct elf_info *info, } } - mod->unres = alloc_symbol(symname, - ELF_ST_BIND(sym->st_info) == STB_WEAK, - mod->unres); + sym_add_unresolved(symname, mod, + ELF_ST_BIND(sym->st_info) == STB_WEAK); break; default: /* All exported symbols */ @@ -2082,7 +2085,7 @@ static void read_symbols(const char *modname) * the automatic versioning doesn't pick it up, but it's really * important anyhow */ if (modversions) - mod->unres = alloc_symbol("module_layout", false, mod->unres); + sym_add_unresolved("module_layout", mod, false); } static void read_symbols_from_files(const char *filename) -- cgit v1.2.3 From 8a69152be9a8c1f7a02c6b8410b35c68cb200f6d Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 1 May 2022 17:40:12 +0900 Subject: modpost: traverse unresolved symbols in order Currently, modpost manages unresolved in a singly linked list; it adds a new node to the head, and traverses the list from new to old. Use a doubly linked list to keep the order in the symbol table in the ELF file. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 20 ++++++++++++++------ scripts/mod/modpost.h | 2 +- 2 files changed, 15 insertions(+), 7 deletions(-) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 59d817692893..70a66ce9ffd9 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -185,6 +185,8 @@ static struct module *new_module(const char *modname) mod = NOFAIL(malloc(sizeof(*mod) + strlen(modname) + 1)); memset(mod, 0, sizeof(*mod)); + INIT_LIST_HEAD(&mod->unresolved_symbols); + strcpy(mod->name, modname); mod->is_vmlinux = (strcmp(modname, "vmlinux") == 0); @@ -207,6 +209,7 @@ static struct module *new_module(const char *modname) struct symbol { struct symbol *next; + struct list_head list; /* link to module::unresolved_symbols */ struct module *module; char *namespace; unsigned int crc; @@ -261,8 +264,12 @@ static struct symbol *new_symbol(const char *name, struct module *module, static void sym_add_unresolved(const char *name, struct module *mod, bool weak) { - mod->unres = alloc_symbol(name, mod->unres); - mod->unres->weak = weak; + struct symbol *sym; + + sym = alloc_symbol(name, NULL); + sym->weak = weak; + + list_add_tail(&sym->list, &mod->unresolved_symbols); } static struct symbol *find_symbol(const char *name) @@ -2156,7 +2163,7 @@ static void check_exports(struct module *mod) { struct symbol *s, *exp; - for (s = mod->unres; s; s = s->next) { + list_for_each_entry(s, &mod->unresolved_symbols, list) { const char *basename; exp = find_symbol(s->name); if (!exp) { @@ -2277,7 +2284,7 @@ static void add_versions(struct buffer *b, struct module *mod) buf_printf(b, "static const struct modversion_info ____versions[]\n"); buf_printf(b, "__used __section(\"__versions\") = {\n"); - for (s = mod->unres; s; s = s->next) { + list_for_each_entry(s, &mod->unresolved_symbols, list) { if (!s->module) continue; if (!s->crc_valid) { @@ -2303,13 +2310,14 @@ static void add_depends(struct buffer *b, struct module *mod) int first = 1; /* Clear ->seen flag of modules that own symbols needed by this. */ - for (s = mod->unres; s; s = s->next) + list_for_each_entry(s, &mod->unresolved_symbols, list) { if (s->module) s->module->seen = s->module->is_vmlinux; + } buf_printf(b, "\n"); buf_printf(b, "MODULE_INFO(depends, \""); - for (s = mod->unres; s; s = s->next) { + list_for_each_entry(s, &mod->unresolved_symbols, list) { const char *p; if (!s->module) continue; diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h index 69601f36d080..f06bbd0ba93c 100644 --- a/scripts/mod/modpost.h +++ b/scripts/mod/modpost.h @@ -113,8 +113,8 @@ buf_write(struct buffer *buf, const char *s, int len); struct module { struct list_head list; + struct list_head unresolved_symbols; bool is_gpl_compatible; - struct symbol *unres; bool from_dump; /* true if module was loaded from *.symvers */ bool is_vmlinux; bool seen; -- cgit v1.2.3 From 4484054816cab940fc2fde23fa989174fec889d0 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 1 May 2022 17:40:13 +0900 Subject: modpost: use doubly linked list for dump_lists This looks easier to understand (just because this is a pattern in the kernel code). No functional change is intended. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 24 ++++++++++-------------- 1 file changed, 10 insertions(+), 14 deletions(-) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 70a66ce9ffd9..a6a55f359396 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -2505,7 +2505,7 @@ static void write_namespace_deps_files(const char *fname) } struct dump_list { - struct dump_list *next; + struct list_head list; const char *file; }; @@ -2517,8 +2517,8 @@ int main(int argc, char **argv) char *dump_write = NULL, *files_source = NULL; int opt; int n; - struct dump_list *dump_read_start = NULL; - struct dump_list **dump_read_iter = &dump_read_start; + LIST_HEAD(dump_lists); + struct dump_list *dl, *dl2; while ((opt = getopt(argc, argv, "ei:mnT:o:awENd:")) != -1) { switch (opt) { @@ -2526,10 +2526,9 @@ int main(int argc, char **argv) external_module = true; break; case 'i': - *dump_read_iter = - NOFAIL(calloc(1, sizeof(**dump_read_iter))); - (*dump_read_iter)->file = optarg; - dump_read_iter = &(*dump_read_iter)->next; + dl = NOFAIL(malloc(sizeof(*dl))); + dl->file = optarg; + list_add_tail(&dl->list, &dump_lists); break; case 'm': modversions = true; @@ -2563,13 +2562,10 @@ int main(int argc, char **argv) } } - while (dump_read_start) { - struct dump_list *tmp; - - read_dump(dump_read_start->file); - tmp = dump_read_start->next; - free(dump_read_start); - dump_read_start = tmp; + list_for_each_entry_safe(dl, dl2, &dump_lists, list) { + read_dump(dl->file); + list_del(&dl->list); + free(dl); } while (optind < argc) -- cgit v1.2.3 From ab489d6002fc27dc5db6d66f121da6fc0bda13ad Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 1 May 2022 17:40:14 +0900 Subject: modpost: traverse the namespace_list in order Use the doubly linked list to traverse the list in the added order. This makes the code more consistent. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 33 +++++++++++++++------------------ scripts/mod/modpost.h | 4 ++-- 2 files changed, 17 insertions(+), 20 deletions(-) (limited to 'scripts/mod') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index a6a55f359396..8bdde738803f 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -186,6 +186,8 @@ static struct module *new_module(const char *modname) memset(mod, 0, sizeof(*mod)); INIT_LIST_HEAD(&mod->unresolved_symbols); + INIT_LIST_HEAD(&mod->missing_namespaces); + INIT_LIST_HEAD(&mod->imported_namespaces); strcpy(mod->name, modname); mod->is_vmlinux = (strcmp(modname, "vmlinux") == 0); @@ -288,39 +290,34 @@ static struct symbol *find_symbol(const char *name) } struct namespace_list { - struct namespace_list *next; + struct list_head list; char namespace[]; }; -static bool contains_namespace(struct namespace_list *list, - const char *namespace) +static bool contains_namespace(struct list_head *head, const char *namespace) { - for (; list; list = list->next) + struct namespace_list *list; + + list_for_each_entry(list, head, list) { if (!strcmp(list->namespace, namespace)) return true; + } return false; } -static void add_namespace(struct namespace_list **list, const char *namespace) +static void add_namespace(struct list_head *head, const char *namespace) { struct namespace_list *ns_entry; - if (!contains_namespace(*list, namespace)) { - ns_entry = NOFAIL(malloc(sizeof(struct namespace_list) + + if (!contains_namespace(head, namespace)) { + ns_entry = NOFAIL(malloc(sizeof(*ns_entry) + strlen(namespace) + 1)); strcpy(ns_entry->namespace, namespace); - ns_entry->next = *list; - *list = ns_entry; + list_add_tail(&ns_entry->list, head); } } -static bool module_imports_namespace(struct module *module, - const char *namespace) -{ - return contains_namespace(module->imported_namespaces, namespace); -} - static const struct { const char *str; enum export export; @@ -2190,7 +2187,7 @@ static void check_exports(struct module *mod) basename = mod->name; if (exp->namespace && - !module_imports_namespace(mod, exp->namespace)) { + !contains_namespace(&mod->imported_namespaces, exp->namespace)) { modpost_log(allow_missing_ns_imports ? LOG_WARN : LOG_ERROR, "module %s uses symbol %s from namespace %s, but does not import it.\n", basename, exp->name, exp->namespace); @@ -2489,12 +2486,12 @@ static void write_namespace_deps_files(const char *fname) list_for_each_entry(mod, &modules, list) { - if (mod->from_dump || !mod->missing_namespaces) + if (mod->from_dump || list_empty(&mod->missing_namespaces)) continue; buf_printf(&ns_deps_buf, "%s.ko:", mod->name); - for (ns = mod->missing_namespaces; ns; ns = ns->next) + list_for_each_entry(ns, &mod->missing_namespaces, list) buf_printf(&ns_deps_buf, " %s", ns->namespace); buf_printf(&ns_deps_buf, "\n"); diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h index f06bbd0ba93c..2e13a736ab38 100644 --- a/scripts/mod/modpost.h +++ b/scripts/mod/modpost.h @@ -123,9 +123,9 @@ struct module { struct buffer dev_table_buf; char srcversion[25]; // Missing namespace dependencies - struct namespace_list *missing_namespaces; + struct list_head missing_namespaces; // Actual imported namespaces - struct namespace_list *imported_namespaces; + struct list_head imported_namespaces; char name[]; }; -- cgit v1.2.3 From f841536e8c5b28e1fbf8743911ae1dc78993abd4 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 1 May 2022 17:40:15 +0900 Subject: modpost: dump Module.symvers in the same order of modules.order