From c90c6bfac6dfd6a7367f718df370b6a19756efe5 Mon Sep 17 00:00:00 2001 From: Behan Webster Date: Fri, 21 Apr 2017 11:20:01 -0700 Subject: [PATCH 01/33] UPSTREAM: kbuild: Add better clang cross build support MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add cross target to CC if using clang. Also add custom gcc toolchain path for fallback gcc tools. Clang will fallback to using things like ld, as, and libgcc if (respectively) one of the llvm linkers isn't available, the integrated assembler is turned off, or an appropriately cross-compiled version of compiler-rt isn't available. To this end, you can specify the path to this fallback gcc toolchain with GCC_TOOLCHAIN. Signed-off-by: Behan Webster Reviewed-by: Jan-Simon Möller Reviewed-by: Mark Charlebois Signed-off-by: Greg Hackmann Signed-off-by: Matthias Kaehlcke Signed-off-by: Masahiro Yamada (cherry picked from commit 785f11aa595bc3d4e74096cbd598ada54ecc0d81) --- Makefile | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/Makefile b/Makefile index feab5f5a507c..6595969ed89b 100644 --- a/Makefile +++ b/Makefile @@ -699,6 +699,15 @@ endif KBUILD_CFLAGS += $(stackp-flag) ifeq ($(cc-name),clang) +ifneq ($(CROSS_COMPILE),) +CLANG_TARGET := -target $(notdir $(CROSS_COMPILE:%-=%)) +GCC_TOOLCHAIN := $(realpath $(dir $(shell which $(LD)))/..) +endif +ifneq ($(GCC_TOOLCHAIN),) +CLANG_GCC_TC := -gcc-toolchain $(GCC_TOOLCHAIN) +endif +KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) +KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,) KBUILD_CPPFLAGS += $(call cc-option,-Wno-unknown-warning-option,) KBUILD_CFLAGS += $(call cc-disable-warning, unused-variable) From dda20e821420e8b5d190317db77a7630b8e8a294 Mon Sep 17 00:00:00 2001 From: Michael Davidson Date: Tue, 25 Apr 2017 15:47:35 -0700 Subject: [PATCH 02/33] UPSTREAM: kbuild: clang: add -no-integrated-as to KBUILD_[AC]FLAGS The Linux Kernel relies on GCC's acceptance of inline assembly as an opaque object which will not have any validation performed on the content. The current behaviour in LLVM is to perform validation of the contents by means of parsing the input if the MC layer can handle it. Disable clangs integrated assembler and use the GNU assembler instead. Wording-mostly-from: Saleem Abdulrasool Signed-off-by: Michael Davidson Signed-off-by: Matthias Kaehlcke Signed-off-by: Masahiro Yamada (cherry picked from commit a37c45cd82e62a361706b9688a984a3a63957321) --- Makefile | 2 ++ 1 file changed, 2 insertions(+) diff --git a/Makefile b/Makefile index 6595969ed89b..7560f0c03526 100644 --- a/Makefile +++ b/Makefile @@ -720,6 +720,8 @@ KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare) # See modpost pattern 2 KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,) KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior) +KBUILD_CFLAGS += $(call cc-option, -no-integrated-as) +KBUILD_AFLAGS += $(call cc-option, -no-integrated-as) else # These warnings generated too much noise in a regular build. From 67259a687d26ee48f0f758379ca410f55194f9ff Mon Sep 17 00:00:00 2001 From: Matthias Kaehlcke Date: Wed, 12 Apr 2017 12:43:52 -0700 Subject: [PATCH 03/33] UPSTREAM: kbuild: Consolidate header generation from ASM offset information Largely redundant code is used in different places to generate C headers from offset information extracted from assembly language output. Consolidate the code in Makefile.lib and use this instead. Signed-off-by: Matthias Kaehlcke Signed-off-by: Masahiro Yamada (cherry picked from commit ebf003f0cfb3705e60d40dedc3ec949176c741af) --- Kbuild | 25 ------------------------- arch/ia64/kernel/Makefile | 26 ++------------------------ scripts/Makefile.lib | 28 ++++++++++++++++++++++++++++ scripts/mod/Makefile | 28 ++-------------------------- 4 files changed, 32 insertions(+), 75 deletions(-) diff --git a/Kbuild b/Kbuild index 3d0ae152af7c..94c752762bc2 100644 --- a/Kbuild +++ b/Kbuild @@ -7,31 +7,6 @@ # 4) Check for missing system calls # 5) Generate constants.py (may need bounds.h) -# Default sed regexp - multiline due to syntax constraints -define sed-y - "/^->/{s:->#\(.*\):/* \1 */:; \ - s:^->\([^ ]*\) [\$$#]*\([-0-9]*\) \(.*\):#define \1 \2 /* \3 */:; \ - s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \ - s:->::; p;}" -endef - -# Use filechk to avoid rebuilds when a header changes, but the resulting file -# does not -define filechk_offsets - (set -e; \ - echo "#ifndef $2"; \ - echo "#define $2"; \ - echo "/*"; \ - echo " * DO NOT MODIFY."; \ - echo " *"; \ - echo " * This file was generated by Kbuild"; \ - echo " */"; \ - echo ""; \ - sed -ne $(sed-y); \ - echo ""; \ - echo "#endif" ) -endef - ##### # 1) Generate bounds.h diff --git a/arch/ia64/kernel/Makefile b/arch/ia64/kernel/Makefile index 3686d6abafde..9edda5466020 100644 --- a/arch/ia64/kernel/Makefile +++ b/arch/ia64/kernel/Makefile @@ -50,32 +50,10 @@ CFLAGS_traps.o += -mfixed-range=f2-f5,f16-f31 # The gate DSO image is built using a special linker script. include $(src)/Makefile.gate -# Calculate NR_IRQ = max(IA64_NATIVE_NR_IRQS, XEN_NR_IRQS, ...) based on config -define sed-y - "/^->/{s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; s:->::; p;}" -endef -quiet_cmd_nr_irqs = GEN $@ -define cmd_nr_irqs - (set -e; \ - echo "#ifndef __ASM_NR_IRQS_H__"; \ - echo "#define __ASM_NR_IRQS_H__"; \ - echo "/*"; \ - echo " * DO NOT MODIFY."; \ - echo " *"; \ - echo " * This file was generated by Kbuild"; \ - echo " *"; \ - echo " */"; \ - echo ""; \ - sed -ne $(sed-y) $<; \ - echo ""; \ - echo "#endif" ) > $@ -endef - # We use internal kbuild rules to avoid the "is up to date" message from make arch/$(SRCARCH)/kernel/nr-irqs.s: arch/$(SRCARCH)/kernel/nr-irqs.c $(Q)mkdir -p $(dir $@) $(call if_changed_dep,cc_s_c) -include/generated/nr-irqs.h: arch/$(SRCARCH)/kernel/nr-irqs.s - $(Q)mkdir -p $(dir $@) - $(call cmd,nr_irqs) +include/generated/nr-irqs.h: arch/$(SRCARCH)/kernel/nr-irqs.s FORCE + $(call filechk,offsets,__ASM_NR_IRQS_H__) diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index d3d3320722cb..530fae970c0a 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -414,3 +414,31 @@ quiet_cmd_xzmisc = XZMISC $@ cmd_xzmisc = (cat $(filter-out FORCE,$^) | \ xz --check=crc32 --lzma2=dict=1MiB) > $@ || \ (rm -f $@ ; false) + +# ASM offsets +# --------------------------------------------------------------------------- + +# Default sed regexp - multiline due to syntax constraints +define sed-offsets + "/^->/{s:->#\(.*\):/* \1 */:; \ + s:^->\([^ ]*\) [\$$#]*\([-0-9]*\) \(.*\):#define \1 \2 /* \3 */:; \ + s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \ + s:->::; p;}" +endef + +# Use filechk to avoid rebuilds when a header changes, but the resulting file +# does not +define filechk_offsets + (set -e; \ + echo "#ifndef $2"; \ + echo "#define $2"; \ + echo "/*"; \ + echo " * DO NOT MODIFY."; \ + echo " *"; \ + echo " * This file was generated by Kbuild"; \ + echo " */"; \ + echo ""; \ + sed -ne $(sed-offsets); \ + echo ""; \ + echo "#endif" ) +endef diff --git a/scripts/mod/Makefile b/scripts/mod/Makefile index 19d9bcadc0cc..b497d9764dcf 100644 --- a/scripts/mod/Makefile +++ b/scripts/mod/Makefile @@ -7,32 +7,8 @@ modpost-objs := modpost.o file2alias.o sumversion.o devicetable-offsets-file := devicetable-offsets.h -define sed-y - "/^->/{s:->#\(.*\):/* \1 */:; \ - s:^->\([^ ]*\) [\$$#]*\([-0-9]*\) \(.*\):#define \1 \2 /* \3 */:; \ - s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \ - s:->::; p;}" -endef - -quiet_cmd_offsets = GEN $@ -define cmd_offsets - (set -e; \ - echo "#ifndef __DEVICETABLE_OFFSETS_H__"; \ - echo "#define __DEVICETABLE_OFFSETS_H__"; \ - echo "/*"; \ - echo " * DO NOT MODIFY."; \ - echo " *"; \ - echo " * This file was generated by Kbuild"; \ - echo " *"; \ - echo " */"; \ - echo ""; \ - sed -ne $(sed-y) $<; \ - echo ""; \ - echo "#endif" ) > $@ -endef - -$(obj)/$(devicetable-offsets-file): $(obj)/devicetable-offsets.s - $(call if_changed,offsets) +$(obj)/$(devicetable-offsets-file): $(obj)/devicetable-offsets.s FORCE + $(call filechk,offsets,__DEVICETABLE_OFFSETS_H__) targets += $(devicetable-offsets-file) devicetable-offsets.s From 9ba72a2322625c03ad04d5857c6655091c25851a Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Fri, 21 Apr 2017 15:21:10 +0900 Subject: [PATCH 04/33] UPSTREAM: kbuild: consolidate redundant sed script ASM offset generation This part ended up in redundant code after touched by multiple people. [1] Commit 3234282f33b2 ("x86, asm: Fix CFI macro invocations to deal with shortcomings in gas") added parentheses for defined expressions to support old gas for x86. [2] Commit a22dcdb0032c ("x86, asm: Fix ancient-GAS workaround") split the pattern into two to avoid parentheses for non-numeric expressions. [3] Commit 95a2f6f72d37 ("Partially revert patch that encloses asm-offset.h numbers in brackets") removed parentheses from numeric expressions as well because parentheses in MN10300 assembly have a special meaning (pointer access). Apparently, there is a conflict between [1] and [3]. After all, [3] took precedence, and a long time has passed since then. Now, merge the two patterns again because the first one is covered by the other. Signed-off-by: Masahiro Yamada Reviewed-by: Matthias Kaehlcke (cherry picked from commit 7dd47b95b0f54f2057d40af6e66d477e3fe95d13) --- scripts/Makefile.lib | 1 - 1 file changed, 1 deletion(-) diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 530fae970c0a..c285493e89b5 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -421,7 +421,6 @@ cmd_xzmisc = (cat $(filter-out FORCE,$^) | \ # Default sed regexp - multiline due to syntax constraints define sed-offsets "/^->/{s:->#\(.*\):/* \1 */:; \ - s:^->\([^ ]*\) [\$$#]*\([-0-9]*\) \(.*\):#define \1 \2 /* \3 */:; \ s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \ s:->::; p;}" endef From ba790f583c30575ec1705286407f213fddd03ccf Mon Sep 17 00:00:00 2001 From: Jeroen Hofstee Date: Fri, 21 Apr 2017 15:21:11 +0900 Subject: [PATCH 05/33] UPSTREAM: kbuild: fix asm-offset generation to work with clang KBuild abuses the asm statement to write to a file and clang chokes about these invalid asm statements. Hack it even more by fooling this is actual valid asm code. [masahiro: Import Jeroen's work for U-Boot: http://patchwork.ozlabs.org/patch/375026/ Tweak sed script a little to avoid garbage '#' for GCC case, like #define NR_PAGEFLAGS 23 /* __NR_PAGEFLAGS # */ ] Signed-off-by: Jeroen Hofstee Signed-off-by: Masahiro Yamada Reviewed-by: Matthias Kaehlcke Tested-by: Matthias Kaehlcke (cherry picked from commit cf0c3e68aa81f992b0301f62e341b710d385bf68) --- include/linux/kbuild.h | 6 +++--- scripts/Makefile.lib | 8 ++++++-- 2 files changed, 9 insertions(+), 5 deletions(-) diff --git a/include/linux/kbuild.h b/include/linux/kbuild.h index 22a72198c14b..4e80f3a9ad58 100644 --- a/include/linux/kbuild.h +++ b/include/linux/kbuild.h @@ -2,14 +2,14 @@ #define __LINUX_KBUILD_H #define DEFINE(sym, val) \ - asm volatile("\n->" #sym " %0 " #val : : "i" (val)) + asm volatile("\n.ascii \"->" #sym " %0 " #val "\"" : : "i" (val)) -#define BLANK() asm volatile("\n->" : : ) +#define BLANK() asm volatile("\n.ascii \"->\"" : : ) #define OFFSET(sym, str, mem) \ DEFINE(sym, offsetof(struct str, mem)) #define COMMENT(x) \ - asm volatile("\n->#" x) + asm volatile("\n.ascii \"->#" x "\"") #endif diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index c285493e89b5..9e447b8497c6 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -419,10 +419,14 @@ cmd_xzmisc = (cat $(filter-out FORCE,$^) | \ # --------------------------------------------------------------------------- # Default sed regexp - multiline due to syntax constraints +# +# Use [:space:] because LLVM's integrated assembler inserts around +# the .ascii directive whereas GCC keeps the as-is. define sed-offsets - "/^->/{s:->#\(.*\):/* \1 */:; \ + 's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \ + /^->/{s:->#\(.*\):/* \1 */:; \ s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \ - s:->::; p;}" + s:->::; p;}' endef # Use filechk to avoid rebuilds when a header changes, but the resulting file From f9e396078be8a9ddf29db5e4c09cccf30716ef84 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 13 Apr 2017 07:25:21 +0900 Subject: [PATCH 06/33] UPSTREAM: kbuild: drop -Wno-unknown-warning-option from clang options Since commit c3f0d0bc5b01 ("kbuild, LLVMLinux: Add -Werror to cc-option to support clang"), cc-option and friends work nicely for clang. However, -Wno-unknown-warning-option makes clang happy with any unknown warning options even if -Werror is specified. Once -Wno-unknown-warning-option is added, any succeeding call of cc-disable-warning is evaluated positive, then unknown warning options are accepted. This should be dropped. Signed-off-by: Masahiro Yamada (cherry picked from commit a0ae981eba8f07dbc74bce38fd3a462b69a5bc8e) --- Makefile | 1 - scripts/Makefile.extrawarn | 1 - 2 files changed, 2 deletions(-) diff --git a/Makefile b/Makefile index 7560f0c03526..f048e2929507 100644 --- a/Makefile +++ b/Makefile @@ -709,7 +709,6 @@ endif KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,) -KBUILD_CPPFLAGS += $(call cc-option,-Wno-unknown-warning-option,) KBUILD_CFLAGS += $(call cc-disable-warning, unused-variable) KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier) KBUILD_CFLAGS += $(call cc-disable-warning, gnu) diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn index 7c321a603b07..fb3522fd8702 100644 --- a/scripts/Makefile.extrawarn +++ b/scripts/Makefile.extrawarn @@ -64,7 +64,6 @@ ifeq ($(cc-name),clang) KBUILD_CFLAGS += $(call cc-disable-warning, initializer-overrides) KBUILD_CFLAGS += $(call cc-disable-warning, unused-value) KBUILD_CFLAGS += $(call cc-disable-warning, format) -KBUILD_CFLAGS += $(call cc-disable-warning, unknown-warning-option) KBUILD_CFLAGS += $(call cc-disable-warning, sign-compare) KBUILD_CFLAGS += $(call cc-disable-warning, format-zero-length) KBUILD_CFLAGS += $(call cc-disable-warning, uninitialized) From 70de9b20fa2a48c5c2bc4a5c68e2a22240a07650 Mon Sep 17 00:00:00 2001 From: Mark Charlebois Date: Fri, 31 Mar 2017 22:38:13 +0200 Subject: [PATCH 07/33] UPSTREAM: kbuild, LLVMLinux: Add -Werror to cc-option to support clang MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Clang will warn about unknown warnings but will not return false unless -Werror is set. GCC will return false if an unknown warning is passed. Adding -Werror make both compiler behave the same. [arnd: it turns out we need the same patch for testing whether -ffunction-sections works right with gcc. I've build tested extensively with this patch applied, so let's just merge this one now.] Signed-off-by: Mark Charlebois Signed-off-by: Behan Webster Reviewed-by: Jan-Simon Möller Signed-off-by: Arnd Bergmann Acked-by: Kees Cook Signed-off-by: Masahiro Yamada (cherry picked from commit c3f0d0bc5b01ad90c45276952802455750444b4f) --- scripts/Kbuild.include | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index 179219845dfc..715838093ba1 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -116,12 +116,12 @@ CC_OPTION_CFLAGS = $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS)) # Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586) cc-option = $(call try-run,\ - $(CC) $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2)) + $(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2)) # cc-option-yn # Usage: flag := $(call cc-option-yn,-march=winchip-c6) cc-option-yn = $(call try-run,\ - $(CC) $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n) + $(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n) # cc-option-align # Prefix align with either -falign or -malign @@ -131,7 +131,7 @@ cc-option-align = $(subst -functions=0,,\ # cc-disable-warning # Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable) cc-disable-warning = $(call try-run,\ - $(CC) $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1))) + $(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1))) # cc-name # Expands to either gcc or clang From 5db0ac53e751f236c065323c503445ce6c9a5177 Mon Sep 17 00:00:00 2001 From: Behan Webster Date: Mon, 27 Mar 2017 18:19:09 -0700 Subject: [PATCH 08/33] UPSTREAM: kbuild: use -Oz instead of -Os when using clang This generates smaller resulting object code when compiled with clang. Signed-off-by: Behan Webster Signed-off-by: Matthias Kaehlcke Signed-off-by: Masahiro Yamada (cherry picked from commit 6748cb3c299de1ffbe56733647b01dbcc398c419) --- Makefile | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/Makefile b/Makefile index f048e2929507..cfb3289941c7 100644 --- a/Makefile +++ b/Makefile @@ -639,7 +639,8 @@ KBUILD_CFLAGS += $(call cc-option,-fdata-sections,) endif ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE -KBUILD_CFLAGS += -Os $(call cc-disable-warning,maybe-uninitialized,) +KBUILD_CFLAGS += $(call cc-option,-Oz,-Os) +KBUILD_CFLAGS += $(call cc-disable-warning,maybe-uninitialized,) else ifdef CONFIG_PROFILE_ALL_BRANCHES KBUILD_CFLAGS += -O2 $(call cc-disable-warning,maybe-uninitialized,) From 30c02b6d50d7c1714a8df450f5eadf68a24a997a Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Vin=C3=ADcius=20Tinti?= Date: Mon, 24 Apr 2017 13:04:58 -0700 Subject: [PATCH 09/33] UPSTREAM: kbuild: Add support to generate LLVM assembly files MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add rules to kbuild in order to generate LLVM assembly files with the .ll extension when using clang. # from c code make CC=clang kernel/pid.ll Signed-off-by: Vinícius Tinti Signed-off-by: Behan Webster Signed-off-by: Matthias Kaehlcke Signed-off-by: Masahiro Yamada (cherry picked from commit 433db3e260bc8134d4a46ddf20b3668937e12556) --- .gitignore | 1 + Makefile | 5 +++++ scripts/Makefile.build | 8 ++++++++ 3 files changed, 14 insertions(+) diff --git a/.gitignore b/.gitignore index d47ecbb26d72..4105cfbd6f26 100644 --- a/.gitignore +++ b/.gitignore @@ -33,6 +33,7 @@ *.lzo *.patch *.gcno +*.ll modules.builtin Module.symvers *.dwo diff --git a/Makefile b/Makefile index cfb3289941c7..300f01c80c11 100644 --- a/Makefile +++ b/Makefile @@ -1373,6 +1373,8 @@ help: @echo ' (default: $$(INSTALL_MOD_PATH)/lib/firmware)' @echo ' dir/ - Build all files in dir and below' @echo ' dir/file.[ois] - Build specified target only' + @echo ' dir/file.ll - Build the LLVM assembly file' + @echo ' (requires compiler support for LLVM assembly generation)' @echo ' dir/file.lst - Build specified mixed source/assembly target only' @echo ' (requires a recent binutils and recent build (System.map))' @echo ' dir/file.ko - Build module including final link' @@ -1557,6 +1559,7 @@ clean: $(clean-dirs) -o -name '*.symtypes' -o -name 'modules.order' \ -o -name modules.builtin -o -name '.tmp_*.o.*' \ -o -name '*.c.[012]*.*' \ + -o -name '*.ll' \ -o -name '*.gcno' \) -type f -print | xargs rm -f # Generate tags for editors @@ -1660,6 +1663,8 @@ endif $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@) %.symtypes: %.c prepare scripts FORCE $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@) +%.ll: %.c prepare scripts FORCE + $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@) # Modules /: prepare scripts FORCE diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 7675d11ee65e..3e3efd37ba47 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -176,6 +176,14 @@ cmd_cc_symtypes_c = \ $(obj)/%.symtypes : $(src)/%.c FORCE $(call cmd,cc_symtypes_c) +# LLVM assembly +# Generate .ll files from .c +quiet_cmd_cc_ll_c = CC $(quiet_modtag) $@ + cmd_cc_ll_c = $(CC) $(c_flags) -emit-llvm -S -o $@ $< + +$(obj)/%.ll: $(src)/%.c FORCE + $(call if_changed_dep,cc_ll_c) + # C (.c) files # The C file is compiled and updated dependency information is generated. # (See cmd_cc_o_c + relevant part of rule_cc_o_c) From 2fe1b761fa48d8e62aec6cd4598982a5e8f215cd Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Wed, 1 Feb 2017 18:00:14 +0100 Subject: [PATCH 10/33] UPSTREAM: modules: mark __inittest/__exittest as __maybe_unused clang warns about unused inline functions by default: arch/arm/crypto/aes-cipher-glue.c:68:1: warning: unused function '__inittest' [-Wunused-function] arch/arm/crypto/aes-cipher-glue.c:69:1: warning: unused function '__exittest' [-Wunused-function] As these appear in every single module, let's just disable the warnings by marking the two functions as __maybe_unused. Signed-off-by: Arnd Bergmann Reviewed-by: Miroslav Benes Acked-by: Rusty Russell Signed-off-by: Jessica Yu (cherry picked from commit 1f318a8bafcfba9f0d623f4870c4e890fd22e659) --- include/linux/module.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/include/linux/module.h b/include/linux/module.h index 0c3207d26ac0..1226280be63b 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -127,13 +127,13 @@ extern void cleanup_module(void); /* Each module must use one module_init(). */ #define module_init(initfn) \ - static inline initcall_t __inittest(void) \ + static inline initcall_t __maybe_unused __inittest(void) \ { return initfn; } \ int init_module(void) __attribute__((alias(#initfn))); /* This is only required if you want to be unloadable. */ #define module_exit(exitfn) \ - static inline exitcall_t __exittest(void) \ + static inline exitcall_t __maybe_unused __exittest(void) \ { return exitfn; } \ void cleanup_module(void) __attribute__((alias(#exitfn))); From f0f3d6753fc45096255001666fce5dfb8a376109 Mon Sep 17 00:00:00 2001 From: David Rientjes Date: Tue, 6 Jun 2017 13:36:24 -0700 Subject: [PATCH 11/33] UPSTREAM: compiler, clang: suppress warning for unused static inline functions GCC explicitly does not warn for unused static inline functions for -Wunused-function. The manual states: Warn whenever a static function is declared but not defined or a non-inline static function is unused. Clang does warn for static inline functions that are unused. It turns out that suppressing the warnings avoids potentially complex Suppress the warning for clang. Signed-off-by: David Rientjes Signed-off-by: Linus Torvalds (cherry picked from commit abb2ea7dfd82451d85ce669b811310c05ab5ca46) --- include/linux/compiler-clang.h | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/include/linux/compiler-clang.h b/include/linux/compiler-clang.h index de179993e039..ea9126006a69 100644 --- a/include/linux/compiler-clang.h +++ b/include/linux/compiler-clang.h @@ -15,3 +15,10 @@ * with any version that can compile the kernel */ #define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__) + +/* + * GCC does not warn about unused static inline functions for + * -Wunused-function. This turns out to avoid the need for complex #ifdef + * directives. Suppress the warning in clang as well. + */ +#define inline inline __attribute__((unused)) From 27836ce36ad7106bfabb7d48b6ac4053bbd29001 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 11 Jun 2017 15:51:56 -0700 Subject: [PATCH 12/33] UPSTREAM: compiler, clang: properly override 'inline' for clang Commit abb2ea7dfd82 ("compiler, clang: suppress warning for unused static inline functions") just caused more warnings due to re-defining the 'inline' macro. So undef it before re-defining it, and also add the 'notrace' attribute like the gcc version that this is overriding does. Maybe this makes clang happier. Signed-off-by: Linus Torvalds (cherry picked from commit 6d53cefb18e4646fb4bf62ccb6098fb3808486df) --- include/linux/compiler-clang.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/include/linux/compiler-clang.h b/include/linux/compiler-clang.h index ea9126006a69..d614c5ea1b5e 100644 --- a/include/linux/compiler-clang.h +++ b/include/linux/compiler-clang.h @@ -21,4 +21,5 @@ * -Wunused-function. This turns out to avoid the need for complex #ifdef * directives. Suppress the warning in clang as well. */ -#define inline inline __attribute__((unused)) +#undef inline +#define inline inline __attribute__((unused)) notrace From d89051f0fe6bc8bba2d6e273c8f9e45fbbea6e2b Mon Sep 17 00:00:00 2001 From: Matthias Kaehlcke Date: Thu, 13 Apr 2017 10:26:09 -0700 Subject: [PATCH 13/33] UPSTREAM: x86/kbuild: Use cc-option to enable -falign-{jumps/loops} clang currently does not support these optimizations, only enable them when they are available. Signed-off-by: Matthias Kaehlcke Cc: Greg Hackmann Cc: Linus Torvalds Cc: Masahiro Yamada Cc: Michael Davidson Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: grundler@chromium.org Link: http://lkml.kernel.org/r/20170413172609.118122-1-mka@chromium.org Signed-off-by: Ingo Molnar (cherry picked from commit 2c4fd1ac3ff167c91272dc43c7bfd2269ef61557) --- arch/x86/Makefile | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 75725dc4df7a..af0735ec2ef8 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -88,10 +88,10 @@ else KBUILD_CFLAGS += -m64 # Align jump targets to 1 byte, not the default 16 bytes: - KBUILD_CFLAGS += -falign-jumps=1 + KBUILD_CFLAGS += $(call cc-option,-falign-jumps=1) # Pack loops tightly as well: - KBUILD_CFLAGS += -falign-loops=1 + KBUILD_CFLAGS += $(call cc-option,-falign-loops=1) # Don't autogenerate traditional x87 instructions KBUILD_CFLAGS += $(call cc-option,-mno-80387) From 19e1bc3d3b1ac206402f5c03476d5355c0f00024 Mon Sep 17 00:00:00 2001 From: Michael Davidson Date: Wed, 15 Mar 2017 15:36:00 -0700 Subject: [PATCH 14/33] UPSTREAM: crypto, x86: aesni - fix token pasting for clang aes_ctrby8_avx-x86_64.S uses the C preprocessor for token pasting of character sequences that are not valid preprocessor tokens. While this is allowed when preprocessing assembler files it exposes an incompatibilty between the clang and gcc preprocessors where clang does not strip leading white space from macro parameters, leading to the CONCAT(%xmm, i) macro expansion on line 96 resulting in a token with a space character embedded in it. While this could be resolved by deleting the offending space character, the assembler is perfectly capable of doing the token pasting correctly for itself so we can just get rid of the preprocessor macros. Signed-off-by: Michael Davidson Signed-off-by: Herbert Xu (cherry picked from commit fdb2726f4e61c5e3abc052f547d5a5f6c0dc5504) --- arch/x86/crypto/aes_ctrby8_avx-x86_64.S | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/arch/x86/crypto/aes_ctrby8_avx-x86_64.S b/arch/x86/crypto/aes_ctrby8_avx-x86_64.S index a916c4a61165..5f6a5af9c489 100644 --- a/arch/x86/crypto/aes_ctrby8_avx-x86_64.S +++ b/arch/x86/crypto/aes_ctrby8_avx-x86_64.S @@ -65,7 +65,6 @@ #include #include -#define CONCAT(a,b) a##b #define VMOVDQ vmovdqu #define xdata0 %xmm0 @@ -92,8 +91,6 @@ #define num_bytes %r8 #define tmp %r10 -#define DDQ(i) CONCAT(ddq_add_,i) -#define XMM(i) CONCAT(%xmm, i) #define DDQ_DATA 0 #define XDATA 1 #define KEY_128 1 @@ -131,12 +128,12 @@ ddq_add_8: /* generate a unique variable for ddq_add_x */ .macro setddq n - var_ddq_add = DDQ(\n) + var_ddq_add = ddq_add_\n .endm /* generate a unique variable for xmm register */ .macro setxdata n - var_xdata = XMM(\n) + var_xdata = %xmm\n .endm /* club the numeric 'id' to the symbol 'name' */ From a79b53cc043bd76038097706bfdd21c8af161c44 Mon Sep 17 00:00:00 2001 From: Matthias Kaehlcke Date: Mon, 1 May 2017 15:47:41 -0700 Subject: [PATCH 15/33] UPSTREAM: x86/mm/kaslr: Use the _ASM_MUL macro for multiplication to work around Clang incompatibility The constraint "rm" allows the compiler to put mix_const into memory. When the input operand is a memory location then MUL needs an operand size suffix, since Clang can't infer the multiplication width from the operand. Add and use the _ASM_MUL macro which determines the operand size and resolves to the NUL instruction with the corresponding suffix. This fixes the following error when building with clang: CC arch/x86/lib/kaslr.o /tmp/kaslr-dfe1ad.s: Assembler messages: /tmp/kaslr-dfe1ad.s:182: Error: no instruction mnemonic suffix given and no register operands; can't size instruction Signed-off-by: Matthias Kaehlcke Cc: Grant Grundler Cc: Greg Hackmann Cc: Kees Cook Cc: Linus Torvalds Cc: Michael Davidson Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20170501224741.133938-1-mka@chromium.org Signed-off-by: Ingo Molnar (cherry picked from commit 121843eb02a6e2fa30aefab64bfe183c97230c75) --- arch/x86/include/asm/asm.h | 1 + arch/x86/lib/kaslr.c | 3 ++- 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/asm.h b/arch/x86/include/asm/asm.h index 7acb51c49fec..7a9df3beb89b 100644 --- a/arch/x86/include/asm/asm.h +++ b/arch/x86/include/asm/asm.h @@ -32,6 +32,7 @@ #define _ASM_ADD __ASM_SIZE(add) #define _ASM_SUB __ASM_SIZE(sub) #define _ASM_XADD __ASM_SIZE(xadd) +#define _ASM_MUL __ASM_SIZE(mul) #define _ASM_AX __ASM_REG(ax) #define _ASM_BX __ASM_REG(bx) diff --git a/arch/x86/lib/kaslr.c b/arch/x86/lib/kaslr.c index 121f59c6ee54..0c7fe444dcdd 100644 --- a/arch/x86/lib/kaslr.c +++ b/arch/x86/lib/kaslr.c @@ -5,6 +5,7 @@ * kernel starts. This file is included in the compressed kernel and * normally linked in the regular. */ +#include #include #include #include @@ -79,7 +80,7 @@ unsigned long kaslr_get_random_long(const char *purpose) } /* Circular multiply for better bit diffusion */ - asm("mul %3" + asm(_ASM_MUL "%3" : "=a" (random), "=d" (raw) : "a" (random), "rm" (mix_const)); random += raw; From 00eea2fac0720f51db40c6beb37aa9e4baa39802 Mon Sep 17 00:00:00 2001 From: Matthias Kaehlcke Date: Wed, 21 Jun 2017 16:28:03 -0700 Subject: [PATCH 16/33] UPSTREAM: kbuild: Add __cc-option macro cc-option uses KBUILD_CFLAGS and KBUILD_CPPFLAGS when it determines whether an option is supported or not. This is fine for options used to build the kernel itself, however some components like the x86 boot code use a different set of flags. Add the new macro __cc-option which is a more generic version of cc-option with additional parameters. One parameter is the compiler with which the check should be performed, the other the compiler options to be used instead KBUILD_C*FLAGS. Refactor cc-option and hostcc-option to use __cc-option and move hostcc-option to scripts/Kbuild.include. Suggested-by: Arnd Bergmann Suggested-by: Masahiro Yamada Signed-off-by: Matthias Kaehlcke Acked-by: Arnd Bergmann Acked-by: Michal Marek Signed-off-by: Masahiro Yamada (cherry picked from commit 9f3f1fd299768782465cb32cdf0dd4528d11f26b) --- Makefile | 2 +- scripts/Kbuild.include | 14 ++++++++++++-- scripts/Makefile.host | 6 ------ 3 files changed, 13 insertions(+), 9 deletions(-) diff --git a/Makefile b/Makefile index 300f01c80c11..b0375795e953 100644 --- a/Makefile +++ b/Makefile @@ -301,7 +301,7 @@ CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \ HOSTCC = gcc HOSTCXX = g++ -HOSTCFLAGS = -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 -fomit-frame-pointer -std=gnu89 +HOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 -fomit-frame-pointer -std=gnu89 HOSTCXXFLAGS = -O2 ifeq ($(shell $(HOSTCC) -v 2>&1 | grep -c "clang version"), 1) diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index 715838093ba1..140a0fa24f84 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -108,6 +108,11 @@ as-option = $(call try-run,\ as-instr = $(call try-run,\ printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3)) +# __cc-option +# Usage: MY_CFLAGS += $(call __cc-option,$(CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586) +__cc-option = $(call try-run,\ + $(1) -Werror $(2) $(3) -c -x c /dev/null -o "$$TMP",$(3),$(4)) + # Do not attempt to build with gcc plugins during cc-option tests. # (And this uses delayed resolution so the flags will be up to date.) CC_OPTION_CFLAGS = $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS)) @@ -115,8 +120,13 @@ CC_OPTION_CFLAGS = $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS)) # cc-option # Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586) -cc-option = $(call try-run,\ - $(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2)) +cc-option = $(call __cc-option, $(CC),\ + $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS),$(1),$(2)) + +# hostcc-option +# Usage: cflags-y += $(call hostcc-option,-march=winchip-c6,-march=i586) +hostcc-option = $(call __cc-option, $(HOSTCC),\ + $(HOSTCFLAGS) $(HOST_EXTRACFLAGS),$(1),$(2)) # cc-option-yn # Usage: flag := $(call cc-option-yn,-march=winchip-c6) diff --git a/scripts/Makefile.host b/scripts/Makefile.host index 45b5b1aaedbd..9cfd5c84d76f 100644 --- a/scripts/Makefile.host +++ b/scripts/Makefile.host @@ -20,12 +20,6 @@ # Will compile qconf as a C++ program, and menu as a C program. # They are linked as C++ code to the executable qconf -# hostcc-option -# Usage: cflags-y += $(call hostcc-option,-march=winchip-c6,-march=i586) - -hostcc-option = $(call try-run,\ - $(HOSTCC) $(HOSTCFLAGS) $(HOST_EXTRACFLAGS) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2)) - __hostprogs := $(sort $(hostprogs-y) $(hostprogs-m)) host-cshlib := $(sort $(hostlibs-y) $(hostlibs-m)) host-cxxshlib := $(sort $(hostcxxlibs-y) $(hostcxxlibs-m)) From a736f347ef2231ac32a6065ff6066cc5da5e8aa9 Mon Sep 17 00:00:00 2001 From: Matthias Kaehlcke Date: Wed, 21 Jun 2017 16:28:04 -0700 Subject: [PATCH 17/33] UPSTREAM: x86/build: Use __cc-option for boot code compiler options cc-option is used to enable compiler options for the boot code if they are available. The macro uses KBUILD_CFLAGS and KBUILD_CPPFLAGS for the check, however these flags aren't used to build the boot code, in consequence cc-option can yield wrong results. For example -mpreferred-stack-boundary=2 is never set with a 64-bit compiler, since the setting is only valid for 16 and 32-bit binaries. This is also the case for 32-bit kernel builds, because the option -m32 is added to KBUILD_CFLAGS after the assignment of REALMODE_CFLAGS. Use __cc-option instead of cc-option for the boot mode options. The macro receives the compiler options as parameter instead of using KBUILD_C*FLAGS, for the boot code we pass REALMODE_CFLAGS. Also use separate statements for the __cc-option checks instead of performing them in the initial assignment of REALMODE_CFLAGS since the variable is an input of the macro. Signed-off-by: Matthias Kaehlcke Acked-by: Ingo Molnar Signed-off-by: Masahiro Yamada (cherry picked from commit 032a2c4f65a2f81c93e161a11197ba19bc14a909) --- arch/x86/Makefile | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/arch/x86/Makefile b/arch/x86/Makefile index af0735ec2ef8..1019233148b9 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -24,10 +24,11 @@ REALMODE_CFLAGS := $(M16_CFLAGS) -g -Os -D__KERNEL__ \ -DDISABLE_BRANCH_PROFILING \ -Wall -Wstrict-prototypes -march=i386 -mregparm=3 \ -fno-strict-aliasing -fomit-frame-pointer -fno-pic \ - -mno-mmx -mno-sse \ - $(call cc-option, -ffreestanding) \ - $(call cc-option, -fno-stack-protector) \ - $(call cc-option, -mpreferred-stack-boundary=2) + -mno-mmx -mno-sse + +REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -ffreestanding) +REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -fno-stack-protector) +REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -mpreferred-stack-boundary=2) export REALMODE_CFLAGS # BITS is used as extension for files which are available in a 32 bit From cc7bf5b9693203cbd9b64d89ae18b44dc7fb3c5f Mon Sep 17 00:00:00 2001 From: Matthias Kaehlcke Date: Wed, 21 Jun 2017 16:28:05 -0700 Subject: [PATCH 18/33] UPSTREAM: x86/build: Specify stack alignment for clang For gcc stack alignment is configured with -mpreferred-stack-boundary=N, clang has the option -mstack-alignment=N for that purpose. Use the same alignment as with gcc. If the alignment is not specified clang assumes an alignment of 16 bytes, as required by the standard ABI. However as mentioned in d9b0cde91c60 ("x86-64, gcc: Use -mpreferred-stack-boundary=3 if supported") the standard kernel entry on x86-64 leaves the stack on an 8-byte boundary, as a consequence clang will keep the stack misaligned. Signed-off-by: Matthias Kaehlcke Acked-by: Ingo Molnar Signed-off-by: Masahiro Yamada (cherry picked from commit d77698df39a512911586834d303275ea5fda74d0) Change-Id: If47392e9cb5cfbb18e06be4867a5b4903aa37301 --- arch/x86/Makefile | 26 +++++++++++++++++++++----- 1 file changed, 21 insertions(+), 5 deletions(-) diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 1019233148b9..7192e539a5ad 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -11,6 +11,14 @@ else KBUILD_DEFCONFIG := $(ARCH)_defconfig endif +# For gcc stack alignment is specified with -mpreferred-stack-boundary, +# clang has the option -mstack-alignment for that purpose. +ifneq ($(call cc-option, -mpreferred-stack-boundary=4),) + cc_stack_align_opt := -mpreferred-stack-boundary +else ifneq ($(call cc-option, -mstack-alignment=4),) + cc_stack_align_opt := -mstack-alignment +endif + # How to compile the 16-bit code. Note we always compile for -march=i386; # that way we can complain to the user if the CPU is insufficient. # @@ -28,7 +36,7 @@ REALMODE_CFLAGS := $(M16_CFLAGS) -g -Os -D__KERNEL__ \ REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -ffreestanding) REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -fno-stack-protector) -REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -mpreferred-stack-boundary=2) +REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), $(cc_stack_align_opt)=2) export REALMODE_CFLAGS # BITS is used as extension for files which are available in a 32 bit @@ -65,8 +73,10 @@ ifeq ($(CONFIG_X86_32),y) # with nonstandard options KBUILD_CFLAGS += -fno-pic - # prevent gcc from keeping the stack 16 byte aligned - KBUILD_CFLAGS += $(call cc-option,-mpreferred-stack-boundary=2) + # Align the stack to the register width instead of using the default + # alignment of 16 bytes. This reduces stack usage and the number of + # alignment instructions. + KBUILD_CFLAGS += $(call cc-option,$(cc_stack_align_opt)=2) # Disable unit-at-a-time mode on pre-gcc-4.0 compilers, it makes gcc use # a lot more stack due to the lack of sharing of stacklots: @@ -100,8 +110,14 @@ else KBUILD_CFLAGS += -fno-pic - # Use -mpreferred-stack-boundary=3 if supported. - KBUILD_CFLAGS += $(call cc-option,-mpreferred-stack-boundary=3) + # By default gcc and clang use a stack alignment of 16 bytes for x86. + # However the standard kernel entry on x86-64 leaves the stack on an + # 8-byte boundary. If the compiler isn't informed about the actual + # alignment it will generate extra alignment instructions for the + # default alignment which keep the stack *mis*aligned. + # Furthermore an alignment to the register width reduces stack usage + # and the number of alignment instructions. + KBUILD_CFLAGS += $(call cc-option,$(cc_stack_align_opt)=3) # Use -mskip-rax-setup if supported. KBUILD_CFLAGS += $(call cc-option,-mskip-rax-setup) From fc7c5de49793f9ba8ed0a936d074b3deba2f57cb Mon Sep 17 00:00:00 2001 From: Matthias Kaehlcke Date: Fri, 21 Apr 2017 14:39:30 -0700 Subject: [PATCH 19/33] UPSTREAM: kbuild: clang: Disable 'address-of-packed-member' warning clang generates plenty of these warnings in different parts of the code, to an extent that the warnings are little more than noise. Disable the 'address-of-packed-member' warning. Signed-off-by: Matthias Kaehlcke Reviewed-by: Douglas Anderson Signed-off-by: Masahiro Yamada (cherry picked from commit bfb38988c51e440fd7062ddf3157f7d8b1dd5d70) --- Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/Makefile b/Makefile index b0375795e953..9fab6a0a5db0 100644 --- a/Makefile +++ b/Makefile @@ -713,6 +713,7 @@ KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,) KBUILD_CFLAGS += $(call cc-disable-warning, unused-variable) KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier) KBUILD_CFLAGS += $(call cc-disable-warning, gnu) +KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member) # Quiet clang warning: comparison of unsigned expression < 0 is always false KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare) # CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the From e2b2ca94b0e101b3f24d82a1934151f29b738121 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Wed, 26 Apr 2017 17:11:32 +0100 Subject: [PATCH 20/33] UPSTREAM: crypto: arm64/sha - avoid non-standard inline asm tricks Replace the inline asm which exports struct offsets as ELF symbols with proper const variables exposing the same values. This works around an issue with Clang which does not interpret the "i" (or "I") constraints in the same way as GCC. Signed-off-by: Ard Biesheuvel Tested-by: Matthias Kaehlcke Signed-off-by: Herbert Xu (cherry picked from commit f4857f4c2ee9aa4e2aacac1a845352b00197fb57) --- arch/arm64/crypto/sha1-ce-core.S | 6 ++++-- arch/arm64/crypto/sha1-ce-glue.c | 11 +++-------- arch/arm64/crypto/sha2-ce-core.S | 6 ++++-- arch/arm64/crypto/sha2-ce-glue.c | 13 +++++-------- 4 files changed, 16 insertions(+), 20 deletions(-) diff --git a/arch/arm64/crypto/sha1-ce-core.S b/arch/arm64/crypto/sha1-ce-core.S index c98e7e849f06..8550408735a0 100644 --- a/arch/arm64/crypto/sha1-ce-core.S +++ b/arch/arm64/crypto/sha1-ce-core.S @@ -82,7 +82,8 @@ ENTRY(sha1_ce_transform) ldr dgb, [x0, #16] /* load sha1_ce_state::finalize */ - ldr w4, [x0, #:lo12:sha1_ce_offsetof_finalize] + ldr_l w4, sha1_ce_offsetof_finalize, x4 + ldr w4, [x0, x4] /* load input */ 0: ld1 {v8.4s-v11.4s}, [x1], #64 @@ -132,7 +133,8 @@ CPU_LE( rev32 v11.16b, v11.16b ) * the padding is handled by the C code in that case. */ cbz x4, 3f - ldr x4, [x0, #:lo12:sha1_ce_offsetof_count] + ldr_l w4, sha1_ce_offsetof_count, x4 + ldr x4, [x0, x4] movi v9.2d, #0 mov x8, #0x80000000 movi v10.2d, #0 diff --git a/arch/arm64/crypto/sha1-ce-glue.c b/arch/arm64/crypto/sha1-ce-glue.c index aefda9868627..ea319c055f5d 100644 --- a/arch/arm64/crypto/sha1-ce-glue.c +++ b/arch/arm64/crypto/sha1-ce-glue.c @@ -17,9 +17,6 @@ #include #include -#define ASM_EXPORT(sym, val) \ - asm(".globl " #sym "; .set " #sym ", %0" :: "I"(val)); - MODULE_DESCRIPTION("SHA1 secure hash using ARMv8 Crypto Extensions"); MODULE_AUTHOR("Ard Biesheuvel "); MODULE_LICENSE("GPL v2"); @@ -32,6 +29,9 @@ struct sha1_ce_state { asmlinkage void sha1_ce_transform(struct sha1_ce_state *sst, u8 const *src, int blocks); +const u32 sha1_ce_offsetof_count = offsetof(struct sha1_ce_state, sst.count); +const u32 sha1_ce_offsetof_finalize = offsetof(struct sha1_ce_state, finalize); + static int sha1_ce_update(struct shash_desc *desc, const u8 *data, unsigned int len) { @@ -52,11 +52,6 @@ static int sha1_ce_finup(struct shash_desc *desc, const u8 *data, struct sha1_ce_state *sctx = shash_desc_ctx(desc); bool finalize = !sctx->sst.count && !(len % SHA1_BLOCK_SIZE); - ASM_EXPORT(sha1_ce_offsetof_count, - offsetof(struct sha1_ce_state, sst.count)); - ASM_EXPORT(sha1_ce_offsetof_finalize, - offsetof(struct sha1_ce_state, finalize)); - /* * Allow the asm code to perform the finalization if there is no * partial data and the input is a round multiple of the block size. diff --git a/arch/arm64/crypto/sha2-ce-core.S b/arch/arm64/crypto/sha2-ce-core.S index 01cfee066837..679c6c002f4f 100644 --- a/arch/arm64/crypto/sha2-ce-core.S +++ b/arch/arm64/crypto/sha2-ce-core.S @@ -88,7 +88,8 @@ ENTRY(sha2_ce_transform) ld1 {dgav.4s, dgbv.4s}, [x0] /* load sha256_ce_state::finalize */ - ldr w4, [x0, #:lo12:sha256_ce_offsetof_finalize] + ldr_l w4, sha256_ce_offsetof_finalize, x4 + ldr w4, [x0, x4] /* load input */ 0: ld1 {v16.4s-v19.4s}, [x1], #64 @@ -136,7 +137,8 @@ CPU_LE( rev32 v19.16b, v19.16b ) * the padding is handled by the C code in that case. */ cbz x4, 3f - ldr x4, [x0, #:lo12:sha256_ce_offsetof_count] + ldr_l w4, sha256_ce_offsetof_count, x4 + ldr x4, [x0, x4] movi v17.2d, #0 mov x8, #0x80000000 movi v18.2d, #0 diff --git a/arch/arm64/crypto/sha2-ce-glue.c b/arch/arm64/crypto/sha2-ce-glue.c index 7cd587564a41..0ed9486f75dd 100644 --- a/arch/arm64/crypto/sha2-ce-glue.c +++ b/arch/arm64/crypto/sha2-ce-glue.c @@ -17,9 +17,6 @@ #include #include -#define ASM_EXPORT(sym, val) \ - asm(".globl " #sym "; .set " #sym ", %0" :: "I"(val)); - MODULE_DESCRIPTION("SHA-224/SHA-256 secure hash using ARMv8 Crypto Extensions"); MODULE_AUTHOR("Ard Biesheuvel "); MODULE_LICENSE("GPL v2"); @@ -32,6 +29,11 @@ struct sha256_ce_state { asmlinkage void sha2_ce_transform(struct sha256_ce_state *sst, u8 const *src, int blocks); +const u32 sha256_ce_offsetof_count = offsetof(struct sha256_ce_state, + sst.count); +const u32 sha256_ce_offsetof_finalize = offsetof(struct sha256_ce_state, + finalize); + static int sha256_ce_update(struct shash_desc *desc, const u8 *data, unsigned int len) { @@ -52,11 +54,6 @@ static int sha256_ce_finup(struct shash_desc *desc, const u8 *data, struct sha256_ce_state *sctx = shash_desc_ctx(desc); bool finalize = !sctx->sst.count && !(len % SHA256_BLOCK_SIZE); - ASM_EXPORT(sha256_ce_offsetof_count, - offsetof(struct sha256_ce_state, sst.count)); - ASM_EXPORT(sha256_ce_offsetof_finalize, - offsetof(struct sha256_ce_state, finalize)); - /* * Allow the asm code to perform the finalization if there is no * partial data and the input is a round multiple of the block size. From ff0a112436e16a2e73a9d227ae2ab52dc0362c30 Mon Sep 17 00:00:00 2001 From: Alexander Potapenko Date: Wed, 19 Jul 2017 20:27:30 +0200 Subject: [PATCH 21/33] UPSTREAM: llist: clang: introduce member_address_is_nonnull() Currently llist_for_each_entry() and llist_for_each_entry_safe() iterate until &pos->member != NULL. But when building the kernel with Clang, the compiler assumes &pos->member cannot be NULL if the member's offset is greater than 0 (which would be equivalent to the object being non-contiguous in memory). Therefore the loop condition is always true, and the loops become infinite. To work around this, introduce the member_address_is_nonnull() macro, which casts object pointer to uintptr_t, thus letting the member pointer to be NULL. Signed-off-by: Alexander Potapenko Tested-by: Sodagudi Prasad Signed-off-by: Linus Torvalds (cherry picked from commit beaec533fc2701a28a4d667f67c9f59c6e4e0d13) --- include/linux/llist.h | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) diff --git a/include/linux/llist.h b/include/linux/llist.h index fd4ca0b4fe0f..ac6796138ba0 100644 --- a/include/linux/llist.h +++ b/include/linux/llist.h @@ -87,6 +87,23 @@ static inline void init_llist_head(struct llist_head *list) #define llist_entry(ptr, type, member) \ container_of(ptr, type, member) +/** + * member_address_is_nonnull - check whether the member address is not NULL + * @ptr: the object pointer (struct type * that contains the llist_node) + * @member: the name of the llist_node within the struct. + * + * This macro is conceptually the same as + * &ptr->member != NULL + * but it works around the fact that compilers can decide that taking a member + * address is never a NULL pointer. + * + * Real objects that start at a high address and have a member at NULL are + * unlikely to exist, but such pointers may be returned e.g. by the + * container_of() macro. + */ +#define member_address_is_nonnull(ptr, member) \ + ((uintptr_t)(ptr) + offsetof(typeof(*(ptr)), member) != 0) + /** * llist_for_each - iterate over some deleted entries of a lock-less list * @pos: the &struct llist_node to use as a loop cursor @@ -121,7 +138,7 @@ static inline void init_llist_head(struct llist_head *list) */ #define llist_for_each_entry(pos, node, member) \ for ((pos) = llist_entry((node), typeof(*(pos)), member); \ - &(pos)->member != NULL; \ + member_address_is_nonnull(pos, member); \ (pos) = llist_entry((pos)->member.next, typeof(*(pos)), member)) /** @@ -143,7 +160,7 @@ static inline void init_llist_head(struct llist_head *list) */ #define llist_for_each_entry_safe(pos, n, node, member) \ for (pos = llist_entry((node), typeof(*pos), member); \ - &pos->member != NULL && \ + member_address_is_nonnull(pos, member) && \ (n = llist_entry(pos->member.next, typeof(*n), member), true); \ pos = n) From 6b763a229af3363c4c7cfd8ccf3bbc33e935529e Mon Sep 17 00:00:00 2001 From: Michael Davidson Date: Mon, 24 Jul 2017 16:51:55 -0700 Subject: [PATCH 22/33] UPSTREAM: x86/boot: #undef memcpy() et al in string.c undef memcpy() and friends in boot/string.c so that the functions defined here will have the correct names, otherwise we end up up trying to redefine __builtin_memcpy() etc. Surprisingly, GCC allows this (and, helpfully, discards the __builtin_ prefix from the function name when compiling it), but clang does not. Adding these #undef's appears to preserve what I assume was the original intent of the code. (cherry picked from commit 18d5e6c34a8eda438d5ad8b3b15f42dab01bf05d) Signed-off-by: Michael Davidson Signed-off-by: Matthias Kaehlcke Acked-by: H. Peter Anvin Cc: Arnd Bergmann Cc: Bernhard.Rosenkranzer@linaro.org Cc: Greg Hackmann Cc: Kees Cook Cc: Linus Torvalds Cc: Nick Desaulniers Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20170724235155.79255-1-mka@chromium.org Signed-off-by: Ingo Molnar --- arch/x86/boot/string.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/x86/boot/string.c b/arch/x86/boot/string.c index 9e240fcba784..08dfce02362c 100644 --- a/arch/x86/boot/string.c +++ b/arch/x86/boot/string.c @@ -16,6 +16,15 @@ #include "ctype.h" #include "string.h" +/* + * Undef these macros so that the functions that we provide + * here will have the correct names regardless of how string.h + * may have chosen to #define them. + */ +#undef memcpy +#undef memset +#undef memcmp + int memcmp(const void *s1, const void *s2, size_t len) { bool diff; From bb41d8f7424cab21d7919dc07647af6191401ea3 Mon Sep 17 00:00:00 2001 From: David Rientjes Date: Thu, 6 Jul 2017 15:35:24 -0700 Subject: [PATCH 23/33] UPSTREAM: compiler, clang: always inline when CONFIG_OPTIMIZE_INLINING is disabled The motivation for commit abb2ea7dfd82 ("compiler, clang: suppress warning for unused static inline functions") was to suppress clang's warnings about unused static inline functions. For configs without CONFIG_OPTIMIZE_INLINING enabled, such as any non-x86 architecture, `inline' in the kernel implies that __attribute__((always_inline)) is used. Some code depends on that behavior, see https://lkml.org/lkml/2017/6/13/918: net/built-in.o: In function `__xchg_mb': arch/arm64/include/asm/cmpxchg.h:99: undefined reference to `__compiletime_assert_99' arch/arm64/include/asm/cmpxchg.h:99: undefined reference to `__compiletime_assert_99 The full fix would be to identify these breakages and annotate the functions with __always_inline instead of `inline'. But since we are late in the 4.12-rc cycle, simply carry forward the forced inlining behavior and work toward moving arm64, and other architectures, toward CONFIG_OPTIMIZE_INLINING behavior. (cherry picked from commit 9a04dbcfb33b4012d0ce8c0282f1e3ca694675b1) Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1706261552200.1075@chino.kir.corp.google.com Signed-off-by: David Rientjes Reported-by: Sodagudi Prasad Tested-by: Sodagudi Prasad Tested-by: Matthias Kaehlcke Cc: Mark Rutland Cc: Will Deacon Cc: Catalin Marinas Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/compiler-clang.h | 8 -------- include/linux/compiler-gcc.h | 18 +++++++++++------- 2 files changed, 11 insertions(+), 15 deletions(-) diff --git a/include/linux/compiler-clang.h b/include/linux/compiler-clang.h index d614c5ea1b5e..de179993e039 100644 --- a/include/linux/compiler-clang.h +++ b/include/linux/compiler-clang.h @@ -15,11 +15,3 @@ * with any version that can compile the kernel */ #define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__) - -/* - * GCC does not warn about unused static inline functions for - * -Wunused-function. This turns out to avoid the need for complex #ifdef - * directives. Suppress the warning in clang as well. - */ -#undef inline -#define inline inline __attribute__((unused)) notrace diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h index 928e5ca0caee..1659f98984fc 100644 --- a/include/linux/compiler-gcc.h +++ b/include/linux/compiler-gcc.h @@ -66,18 +66,22 @@ /* * Force always-inline if the user requests it so via the .config, - * or if gcc is too old: + * or if gcc is too old. + * GCC does not warn about unused static inline functions for + * -Wunused-function. This turns out to avoid the need for complex #ifdef + * directives. Suppress the warning in clang as well by using "unused" + * function attribute, which is redundant but not harmful for gcc. */ #if !defined(CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING) || \ !defined(CONFIG_OPTIMIZE_INLINING) || (__GNUC__ < 4) -#define inline inline __attribute__((always_inline)) notrace -#define __inline__ __inline__ __attribute__((always_inline)) notrace -#define __inline __inline __attribute__((always_inline)) notrace +#define inline inline __attribute__((always_inline,unused)) notrace +#define __inline__ __inline__ __attribute__((always_inline,unused)) notrace +#define __inline __inline __attribute__((always_inline,unused)) notrace #else /* A lot of inline functions can cause havoc with function tracing */ -#define inline inline notrace -#define __inline__ __inline__ notrace -#define __inline __inline notrace +#define inline inline __attribute__((unused)) notrace +#define __inline__ __inline__ __attribute__((unused)) notrace +#define __inline __inline __attribute__((unused)) notrace #endif #define __always_inline inline __attribute__((always_inline)) From 0e38949af667f2fd04a7959c0473a1c6b8a4a4d0 Mon Sep 17 00:00:00 2001 From: Matthias Kaehlcke Date: Wed, 16 Aug 2017 17:47:40 -0700 Subject: [PATCH 24/33] UPSTREAM: x86/build: Fix stack alignment for CLang Commit: d77698df39a5 ("x86/build: Specify stack alignment for clang") intended to use the same stack alignment for clang as with gcc. The two compilers use different options to configure the stack alignment (gcc: -mpreferred-stack-boundary=n, clang: -mstack-alignment=n). The above commit assumes that the clang option uses the same parameter type as gcc, i.e. that the alignment is specified as 2^n. However clang interprets the value of this option literally to use an alignment of n, in consequence the stack remains misaligned. Change the values used with -mstack-alignment to be the actual alignment instead of a power of two. cc-option isn't used here with the typical pattern of KBUILD_CFLAGS += $(call cc-option ...). The reason is that older gcc versions don't support the -mpreferred-stack-boundary option, since cc-option doesn't verify whether the alternative option is valid it would incorrectly select the clang option -mstack-alignment.. Signed-off-by: Matthias Kaehlcke Cc: Arnd Bergmann Cc: Bernhard.Rosenkranzer@linaro.org Cc: Greg Hackmann Cc: Kees Cook Cc: Linus Torvalds Cc: Masahiro Yamada Cc: Michael Davidson Cc: Nick Desaulniers Cc: Peter Zijlstra Cc: Stephen Hines Cc: Thomas Gleixner Cc: dianders@chromium.org Link: http://lkml.kernel.org/r/20170817004740.170588-1-mka@chromium.org Signed-off-by: Ingo Molnar (cherry picked from commit 8f91869766c00622b2eaa8ee567db4f333b78c1a) Change-Id: I1a58d7fe64101b59f5264fefcce4fc593c2ebf2b --- arch/x86/Makefile | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 7192e539a5ad..1a366e49845d 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -14,9 +14,11 @@ endif # For gcc stack alignment is specified with -mpreferred-stack-boundary, # clang has the option -mstack-alignment for that purpose. ifneq ($(call cc-option, -mpreferred-stack-boundary=4),) - cc_stack_align_opt := -mpreferred-stack-boundary -else ifneq ($(call cc-option, -mstack-alignment=4),) - cc_stack_align_opt := -mstack-alignment + cc_stack_align4 := -mpreferred-stack-boundary=2 + cc_stack_align8 := -mpreferred-stack-boundary=3 +else ifneq ($(call cc-option, -mstack-alignment=16),) + cc_stack_align4 := -mstack-alignment=4 + cc_stack_align8 := -mstack-alignment=8 endif # How to compile the 16-bit code. Note we always compile for -march=i386; @@ -36,7 +38,7 @@ REALMODE_CFLAGS := $(M16_CFLAGS) -g -Os -D__KERNEL__ \ REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -ffreestanding) REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -fno-stack-protector) -REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), $(cc_stack_align_opt)=2) +REALMODE_CFLAGS += $(cc_stack_align4) export REALMODE_CFLAGS # BITS is used as extension for files which are available in a 32 bit @@ -76,7 +78,7 @@ ifeq ($(CONFIG_X86_32),y) # Align the stack to the register width instead of using the default # alignment of 16 bytes. This reduces stack usage and the number of # alignment instructions. - KBUILD_CFLAGS += $(call cc-option,$(cc_stack_align_opt)=2) + KBUILD_CFLAGS += $(cc_stack_align4) # Disable unit-at-a-time mode on pre-gcc-4.0 compilers, it makes gcc use # a lot more stack due to the lack of sharing of stacklots: @@ -117,7 +119,7 @@ else # default alignment which keep the stack *mis*aligned. # Furthermore an alignment to the register width reduces stack usage # and the number of alignment instructions. - KBUILD_CFLAGS += $(call cc-option,$(cc_stack_align_opt)=3) + KBUILD_CFLAGS += $(cc_stack_align8) # Use -mskip-rax-setup if supported. KBUILD_CFLAGS += $(call cc-option,-mskip-rax-setup) From ae92169eb94faeb71c9061b14ae13b7ddac47c3c Mon Sep 17 00:00:00 2001 From: Matthias Kaehlcke Date: Thu, 17 Aug 2017 11:20:47 -0700 Subject: [PATCH 25/33] UPSTREAM: x86/build: Use cc-option to validate stack alignment parameter With the following commit: 8f91869766c0 ("x86/build: Fix stack alignment for CLang") cc-option is only used to determine the name of the stack alignment option supported by the compiler, but not to verify that the actual parameter