From 736bb11898ef748da1d805f40d485b66ceac9a3c Mon Sep 17 00:00:00 2001 From: "H. Nikolaus Schaller" Date: Wed, 1 Jul 2020 08:18:27 +0200 Subject: [PATCH 1/3] modpost: remove use of non-standard strsep() in HOSTCC code strsep() is neither standard C nor POSIX and used outside the kernel code here. Using it here requires that the build host supports it out of the box which is e.g. not true for a Darwin build host and using a cross-compiler. This leads to: scripts/mod/modpost.c:145:2: warning: implicit declaration of function 'strsep' [-Wimplicit-function-declaration] return strsep(stringp, "\n"); ^ and a segfault when running MODPOST. See also: https://stackoverflow.com/a/7219504 So let's replace this by strchr() instead of using strsep(). It does not hurt kernel size or speed since this code is run on the build host. Fixes: ac5100f5432967 ("modpost: add read_text_file() and get_line() helpers") Co-developed-by: Masahiro Yamada Signed-off-by: H. Nikolaus Schaller Signed-off-by: Masahiro Yamada --- scripts/mod/modpost.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 6aea65c65745..45f2ab2ec2d4 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -138,11 +138,19 @@ char *read_text_file(const char *filename) char *get_line(char **stringp) { + char *orig = *stringp, *next; + /* do not return the unwanted extra line at EOF */ - if (*stringp && **stringp == '\0') + if (!orig || *orig == '\0') return NULL; - return strsep(stringp, "\n"); + next = strchr(orig, '\n'); + if (next) + *next++ = '\0'; + + *stringp = next; + + return orig; } /* A list of all modules we processed */ From 20b1be59528295e5c2a8812059b8560753dd8e68 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Wed, 8 Jul 2020 01:35:08 +0900 Subject: [PATCH 2/3] kbuild: fix single target builds for external modules MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Commit f566e1fbadb6 ("kbuild: make multiple directory targets work") broke single target builds for external modules. Fix this. Fixes: f566e1fbadb6 ("kbuild: make multiple directory targets work") Reported-by: Bjørn Mork Signed-off-by: Masahiro Yamada Tested-by: Bjørn Mork --- Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Makefile b/Makefile index fe0164a654c7..676f1cfb1d56 100644 --- a/Makefile +++ b/Makefile @@ -1754,7 +1754,7 @@ PHONY += descend $(build-dirs) descend: $(build-dirs) $(build-dirs): prepare $(Q)$(MAKE) $(build)=$@ \ - single-build=$(if $(filter-out $@/, $(filter $@/%, $(single-no-ko))),1) \ + single-build=$(if $(filter-out $@/, $(filter $@/%, $(KBUILD_SINGLE_TARGETS))),1) \ need-builtin=1 need-modorder=1 clean-dirs := $(addprefix _clean_, $(clean-dirs)) From ca9b31f6bb9c6aa9b4e5f0792f39a97bbffb8c51 Mon Sep 17 00:00:00 2001 From: Fangrui Song Date: Tue, 21 Jul 2020 10:31:23 -0700 Subject: [PATCH 3/3] Makefile: Fix GCC_TOOLCHAIN_DIR prefix for Clang cross compilation When CROSS_COMPILE is set (e.g. aarch64-linux-gnu-), if $(CROSS_COMPILE)elfedit is found at /usr/bin/aarch64-linux-gnu-elfedit, GCC_TOOLCHAIN_DIR will be set to /usr/bin/. --prefix= will be set to /usr/bin/ and Clang as of 11 will search for both $(prefix)aarch64-linux-gnu-$needle and $(prefix)$needle. GCC searchs for $(prefix)aarch64-linux-gnu/$version/$needle, $(prefix)aarch64-linux-gnu/$needle and $(prefix)$needle. In practice, $(prefix)aarch64-linux-gnu/$needle rarely contains executables. To better model how GCC's -B/--prefix takes in effect in practice, newer Clang (since https://github.com/llvm/llvm-project/commit/3452a0d8c17f7166f479706b293caf6ac76ffd90) only searches for $(prefix)$needle. Currently it will find /usr/bin/as instead of /usr/bin/aarch64-linux-gnu-as. Set --prefix= to $(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE)) (/usr/bin/aarch64-linux-gnu-) so that newer Clang can find the appropriate cross compiling GNU as (when -no-integrated-as is in effect). Cc: stable@vger.kernel.org Reported-by: Nathan Chancellor Signed-off-by: Fangrui Song Reviewed-by: Nathan Chancellor Tested-by: Nathan Chancellor Tested-by: Nick Desaulniers Link: https://github.com/ClangBuiltLinux/linux/issues/1099 Reviewed-by: Nick Desaulniers Signed-off-by: Masahiro Yamada --- Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Makefile b/Makefile index 676f1cfb1d56..9d9d4166c0be 100644 --- a/Makefile +++ b/Makefile @@ -567,7 +567,7 @@ ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),) ifneq ($(CROSS_COMPILE),) CLANG_FLAGS += --target=$(notdir $(CROSS_COMPILE:%-=%)) GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit)) -CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR) +CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE)) GCC_TOOLCHAIN := $(realpath $(GCC_TOOLCHAIN_DIR)/..) endif ifneq ($(GCC_TOOLCHAIN),)