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* kbuild: upgrade the orphan section warning to an error if CONFIG_WERROR is setXin Li2022-11-011-1/+1
| | | | | | | | | | | | | | | | | | | | | Andrew Cooper suggested upgrading the orphan section warning to a hard link error. However Nathan Chancellor said outright turning the warning into an error with no escape hatch might be too aggressive, as we have had these warnings triggered by new compiler generated sections, and suggested turning orphan sections into an error only if CONFIG_WERROR is set. Kees Cook echoed and emphasized that the mandate from Linus is that we should avoid breaking builds. It wrecks bisection, it causes problems across compiler versions, etc. Thus upgrade the orphan section warning to a hard link error only if CONFIG_WERROR is set. Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com> Suggested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Xin Li <xin3.li@intel.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Tested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20221025073023.16137-2-xin3.li@intel.com
* arm64: vdso32: Add DWARF_DEBUGNathan Chancellor2022-07-011-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When building the 32-bit vDSO with LLVM 15 and CONFIG_DEBUG_INFO, there are the following orphan section warnings: ld.lld: warning: arch/arm64/kernel/vdso32/note.o:(.debug_abbrev) is being placed in '.debug_abbrev' ld.lld: warning: arch/arm64/kernel/vdso32/note.o:(.debug_info) is being placed in '.debug_info' ld.lld: warning: arch/arm64/kernel/vdso32/note.o:(.debug_str_offsets) is being placed in '.debug_str_offsets' ld.lld: warning: arch/arm64/kernel/vdso32/note.o:(.debug_str) is being placed in '.debug_str' ld.lld: warning: arch/arm64/kernel/vdso32/note.o:(.debug_addr) is being placed in '.debug_addr' ld.lld: warning: arch/arm64/kernel/vdso32/note.o:(.debug_line) is being placed in '.debug_line' ld.lld: warning: arch/arm64/kernel/vdso32/note.o:(.debug_line_str) is being placed in '.debug_line_str' ld.lld: warning: arch/arm64/kernel/vdso32/vgettimeofday.o:(.debug_loclists) is being placed in '.debug_loclists' ld.lld: warning: arch/arm64/kernel/vdso32/vgettimeofday.o:(.debug_abbrev) is being placed in '.debug_abbrev' ld.lld: warning: arch/arm64/kernel/vdso32/vgettimeofday.o:(.debug_info) is being placed in '.debug_info' ld.lld: warning: arch/arm64/kernel/vdso32/vgettimeofday.o:(.debug_rnglists) is being placed in '.debug_rnglists' ld.lld: warning: arch/arm64/kernel/vdso32/vgettimeofday.o:(.debug_str_offsets) is being placed in '.debug_str_offsets' ld.lld: warning: arch/arm64/kernel/vdso32/vgettimeofday.o:(.debug_str) is being placed in '.debug_str' ld.lld: warning: arch/arm64/kernel/vdso32/vgettimeofday.o:(.debug_addr) is being placed in '.debug_addr' ld.lld: warning: arch/arm64/kernel/vdso32/vgettimeofday.o:(.debug_frame) is being placed in '.debug_frame' ld.lld: warning: arch/arm64/kernel/vdso32/vgettimeofday.o:(.debug_line) is being placed in '.debug_line' ld.lld: warning: arch/arm64/kernel/vdso32/vgettimeofday.o:(.debug_line_str) is being placed in '.debug_line_str' These are DWARF5 sections, as that is the implicit default version for clang-14 and newer when just '-g' is used. All DWARF sections are handled by the DWARF_DEBUG macro from include/asm-generic/vmlinux.lds.h so use that macro here to fix the warnings regardless of DWARF version. Fixes: 9d4775b332e1 ("arm64: vdso32: enable orphan handling for VDSO") Signed-off-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Link: https://lore.kernel.org/r/20220630153121.1317045-3-nathan@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso32: Shuffle .ARM.exidx section above ELF_DETAILSNathan Chancellor2022-07-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When building the 32-bit vDSO after commit 5c4fb60816ea ("arm64: vdso32: add ARM.exidx* sections"), ld.lld 11 fails to link: ld.lld: error: could not allocate headers ld.lld: error: unable to place section .text at file offset [0x2A0, 0xBB1]; check your linker script for overflows ld.lld: error: unable to place section .comment at file offset [0xBB2, 0xC8A]; check your linker script for overflows ld.lld: error: unable to place section .symtab at file offset [0xC8C, 0xE0B]; check your linker script for overflows ld.lld: error: unable to place section .strtab at file offset [0xE0C, 0xF1C]; check your linker script for overflows ld.lld: error: unable to place section .shstrtab at file offset [0xF1D, 0xFAA]; check your linker script for overflows ld.lld: error: section .ARM.exidx file range overlaps with .hash >>> .ARM.exidx range is [0x90, 0xCF] >>> .hash range is [0xB4, 0xE3] ld.lld: error: section .hash file range overlaps with .ARM.attributes >>> .hash range is [0xB4, 0xE3] >>> .ARM.attributes range is [0xD0, 0x10B] ld.lld: error: section .ARM.attributes file range overlaps with .dynsym >>> .ARM.attributes range is [0xD0, 0x10B] >>> .dynsym range is [0xE4, 0x133] ld.lld: error: section .ARM.exidx virtual address range overlaps with .hash >>> .ARM.exidx range is [0x90, 0xCF] >>> .hash range is [0xB4, 0xE3] ld.lld: error: section .ARM.exidx load address range overlaps with .hash >>> .ARM.exidx range is [0x90, 0xCF] >>> .hash range is [0xB4, 0xE3] This was fixed in ld.lld 12 with a change to match GNU ld's semantics of placing non-SHF_ALLOC sections after SHF_ALLOC sections. To workaround this issue, move the .ARM.exidx section before the .comment, .symtab, .strtab, and .shstrtab sections (ELF_DETAILS) so that those sections remain contiguous with the .ARM.attributes section. Fixes: 5c4fb60816ea ("arm64: vdso32: add ARM.exidx* sections") Link: https://github.com/llvm/llvm-project/commit/ec29538af2e0886a65f479d6a533956a1c478132 Signed-off-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/r/20220630153121.1317045-2-nathan@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso*: place got/plt sections in .rodataJoey Gouly2022-06-281-13/+10
| | | | | | | | | | | | The vDSO will not contain absolute relocations, so place these sections in .rodata. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Link: https://lore.kernel.org/linux-arm-kernel/00abb0c5-6360-0004-353f-e7a88b3bd22c@arm.com/ Cc: Will Deacon <will@kernel.org> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lore.kernel.org/r/20220628151307.35561-3-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso32: add ARM.exidx* sectionsJoey Gouly2022-06-281-0/+1
| | | | | | | | | | These show up when building with clang+lld. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lore.kernel.org/r/20220628151307.35561-2-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso32: enable orphan handling for VDSOJoey Gouly2022-06-231-0/+1
| | | | | | | | | | | | | | | | Like vmlinux, enable orphan-handling for the compat VDSO32. This can catch subtle errors that might arise from unexpected sections being included. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Kees Cook <keescook@chromium.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lore.kernel.org/r/20220510095834.32394-5-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso32: put ELF related sections in the linker scriptJoey Gouly2022-06-231-1/+21
| | | | | | | | | | | | | | | | Use macros from vmlinux.lds.h to explicitly name sections that are included in the compat VDSO32 output. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Kees Cook <keescook@chromium.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lore.kernel.org/r/20220510095834.32394-4-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso: fix makefile dependency on vdso.soJoey Gouly2022-05-101-3/+0
| | | | | | | | | | | | | | | | | | There is currently no dependency for vdso*-wrap.S on vdso*.so, which means that you can get a build that uses a stale vdso*-wrap.o. In commit a5b8ca97fbf8, the file that includes the vdso.so was moved and renamed from arch/arm64/kernel/vdso/vdso.S to arch/arm64/kernel/vdso-wrap.S, when this happened the Makefile was not updated to force the dependcy on vdso.so. Fixes: a5b8ca97fbf8 ("arm64: do not descend to vdso directories twice") Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20220510102721.50811-1-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
* Kbuild: move to -std=gnu11Arnd Bergmann2022-03-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During a patch discussion, Linus brought up the option of changing the C standard version from gnu89 to gnu99, which allows using variable declaration inside of a for() loop. While the C99, C11 and later standards introduce many other features, most of these are already available in gnu89 as GNU extensions as well. An earlier attempt to do this when gcc-5 started defaulting to -std=gnu11 failed because at the time that caused warnings about designated initializers with older compilers. Now that gcc-5.1 is the minimum compiler version used for building kernels, that is no longer a concern. Similarly, the behavior of 'inline' functions changes between gnu89 using gnu_inline behavior and gnu11 using standard c99+ behavior, but this was taken care of by defining 'inline' to include __attribute__((gnu_inline)) in order to allow building with clang a while ago. Nathan Chancellor reported a new -Wdeclaration-after-statement warning that appears in a system header on arm, this still needs a workaround. The differences between gnu99, gnu11, gnu1x and gnu17 are fairly minimal and mainly impact warnings at the -Wpedantic level that the kernel never enables. Between these, gnu11 is the newest version that is supported by all supported compiler versions, though it is only the default on gcc-5, while all other supported versions of gcc or clang default to gnu1x/gnu17. Link: https://lore.kernel.org/lkml/CAHk-=wiyCH7xeHcmiFJ-YgXUy2Jaj7pnkdKpcovt8fYbVFW3TA@mail.gmail.com/ Link: https://github.com/ClangBuiltLinux/linux/issues/1603 Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Marco Elver <elver@google.com> Acked-by: Jani Nikula <jani.nikula@intel.com> Acked-by: David Sterba <dsterba@suse.com> Tested-by: Sedat Dilek <sedat.dilek@gmail.com> Reviewed-by: Alex Shi <alexs@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
* Kbuild: use -Wdeclaration-after-statementMark Rutland2022-03-131-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <mark.rutland@arm.com> [arnd: don't add a duplicate flag to the default set, update changelog] Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM/Clang v13.0.0 (x86-64) Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
* arm64: vdso: remove -nostdlib compiler flagMasahiro Yamada2021-11-081-1/+1
| | | | | | | | | | | | | The -nostdlib option requests the compiler to not use the standard system startup files or libraries when linking. It is effective only when $(CC) is used as a linker driver. Since commit 691efbedc60d ("arm64: vdso: use $(LD) instead of $(CC) to link VDSO"), $(LD) is directly used, hence -nostdlib is unneeded. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Link: https://lore.kernel.org/r/20211107161802.323125-1-masahiroy@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso32: require CROSS_COMPILE_COMPAT for gcc+bfdNick Desaulniers2021-10-211-12/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Similar to commit 231ad7f409f1 ("Makefile: infer --target from ARCH for CC=clang") There really is no point in setting --target based on $CROSS_COMPILE_COMPAT for clang when the integrated assembler is being used, since commit ef94340583ee ("arm64: vdso32: drop -no-integrated-as flag"). Allows COMPAT_VDSO to be selected without setting $CROSS_COMPILE_COMPAT when using clang and lld together. Before: $ ARCH=arm64 CROSS_COMPILE_COMPAT=arm-linux-gnueabi- make -j72 LLVM=1 defconfig $ grep CONFIG_COMPAT_VDSO .config CONFIG_COMPAT_VDSO=y $ ARCH=arm64 make -j72 LLVM=1 defconfig $ grep CONFIG_COMPAT_VDSO .config $ After: $ ARCH=arm64 CROSS_COMPILE_COMPAT=arm-linux-gnueabi- make -j72 LLVM=1 defconfig $ grep CONFIG_COMPAT_VDSO .config CONFIG_COMPAT_VDSO=y $ ARCH=arm64 make -j72 LLVM=1 defconfig $ grep CONFIG_COMPAT_VDSO .config CONFIG_COMPAT_VDSO=y Reviewed-by: Nathan Chancellor <nathan@kernel.org> Suggested-by: Nathan Chancellor <nathan@kernel.org> Tested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lore.kernel.org/r/20211019223646.1146945-5-ndesaulniers@google.com Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso32: suppress error message for 'make mrproper'Nick Desaulniers2021-10-211-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | When running the following command without arm-linux-gnueabi-gcc in one's $PATH, the following warning is observed: $ ARCH=arm64 CROSS_COMPILE_COMPAT=arm-linux-gnueabi- make -j72 LLVM=1 mrproper make[1]: arm-linux-gnueabi-gcc: No such file or directory This is because KCONFIG is not run for mrproper, so CONFIG_CC_IS_CLANG is not set, and we end up eagerly evaluating various variables that try to invoke CC_COMPAT. This is a similar problem to what was observed in commit dc960bfeedb0 ("h8300: suppress error messages for 'make clean'") Reported-by: Lucas Henneman <henneman@google.com> Suggested-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Tested-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/r/20211019223646.1146945-4-ndesaulniers@google.com Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso32: drop test for -march=armv8-aNick Desaulniers2021-10-211-7/+1
| | | | | | | | | | | | | | | As Arnd points out: gcc-4.8 already supported -march=armv8, and we require gcc-5.1 now, so both this #if/#else construct and the corresponding "cc32-option,-march=armv8-a" check should be obsolete now. Link: https://lore.kernel.org/lkml/CAK8P3a3UBEJ0Py2ycz=rHfgog8g3mCOeQOwO0Gmp-iz6Uxkapg@mail.gmail.com/ Suggested-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/r/20211019223646.1146945-3-ndesaulniers@google.com Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso32: drop the test for dmb ishldNick Desaulniers2021-10-211-8/+0
| | | | | | | | | | | | | | | | | | | | | | | | Binutils added support for this instruction in commit e797f7e0b2bedc9328d4a9a0ebc63ca7a2dbbebc which shipped in 2.24 (just missing the 2.23 release) but was cherry-picked into 2.23 in commit 27a50d6755bae906bc73b4ec1a8b448467f0bea1. Thanks to Christian and Simon for helping me with the patch archaeology. According to Documentation/process/changes.rst, the minimum supported version of binutils is 2.23. Since all supported versions of GAS support this instruction, drop the assembler invocation, preprocessor flags/guards, and the cross assembler macro that's now unused. This also avoids a recursive self reference in a follow up cleanup patch. Cc: Christian Biesinger <cbiesinger@google.com> Cc: Simon Marchi <simon.marchi@polymtl.ca> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/r/20211019223646.1146945-2-ndesaulniers@google.com Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso32: drop -no-integrated-as flagNick Desaulniers2021-04-231-8/+0
| | | | | | | | | | | | | | | | | | | | | Clang can assemble these files just fine; this is a relic from the top level Makefile conditionally adding this. We no longer need --prefix, --gcc-toolchain, or -Qunused-arguments flags either with this change, so remove those too. To test building: $ ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- \ CROSS_COMPILE_COMPAT=arm-linux-gnueabi- make LLVM=1 LLVM_IAS=1 \ defconfig arch/arm64/kernel/vdso32/ Suggested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Tested-by: Stephen Boyd <swboyd@chromium.org> Acked-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20210420174427.230228-1-ndesaulniers@google.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* arm64: do not descend to vdso directories twiceMasahiro Yamada2021-01-202-20/+0
| | | | | | | | | | | | | | | | | | | | | | arm64 descends into each vdso directory twice; first in vdso_prepare, second during the ordinary build process. PPC mimicked it and uncovered a problem [1]. In the first descend, Kbuild directly visits the vdso directories, therefore it does not inherit subdir-ccflags-y from upper directories. This means the command line parameters may differ between the two. If it happens, the offset values in the generated headers might be different from real offsets of vdso.so in the kernel. This potential danger should be avoided. The vdso directories are built in the vdso_prepare stage, so the second descend is unneeded. [1]: https://lore.kernel.org/linux-kbuild/CAK7LNARAkJ3_-4gX0VA2UkapbOftuzfSTVMBbgbw=HD8n7N+7w@mail.gmail.com/T/#ma10dcb961fda13f36d42d58fa6cb2da988b7e73a Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Link: https://lore.kernel.org/r/20201218024540.1102650-1-masahiroy@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
* arm64: lto: Strengthen READ_ONCE() to acquire when CONFIG_LTO=yWill Deacon2020-11-091-1/+1
| | | | | | | | | | | | | | | When building with LTO, there is an increased risk of the compiler converting an address dependency headed by a READ_ONCE() invocation into a control dependency and consequently allowing for harmful reordering by the CPU. Ensure that such transformations are harmless by overriding the generic READ_ONCE() definition with one that provides acquire semantics when building with LTO. Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso32: Allow ld.lld to properly link the VDSONathan Chancellor2020-10-261-11/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As it stands now, the vdso32 Makefile hardcodes the linker to ld.bfd using -fuse-ld=bfd with $(CC). This was taken from the arm vDSO Makefile, as the comment notes, done in commit d2b30cd4b722 ("ARM: 8384/1: VDSO: force use of BFD linker"). Commit fe00e50b2db8 ("ARM: 8858/1: vdso: use $(LD) instead of $(CC) to link VDSO") changed that Makefile to use $(LD) directly instead of through $(CC), which matches how the rest of the kernel operates. Since then, LD=ld.lld means that the arm vDSO will be linked with ld.lld, which has shown no problems so far. Allow ld.lld to link this vDSO as we do the regular arm vDSO. To do this, we need to do a few things: * Add a LD_COMPAT variable, which defaults to $(CROSS_COMPILE_COMPAT)ld with gcc and $(LD) if LLVM is 1, which will be ld.lld, or $(CROSS_COMPILE_COMPAT)ld if not, which matches the logic of the main Makefile. It is overrideable for further customization and avoiding breakage. * Eliminate cc32-ldoption, which matches commit 055efab3120b ("kbuild: drop support for cc-ldoption"). With those, we can use $(LD_COMPAT) in cmd_ldvdso and change the flags from compiler linker flags to linker flags directly. We eliminate -mfloat-abi=soft because it is not handled by the linker. Reported-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://github.com/ClangBuiltLinux/linux/issues/1033 Link: https://lore.kernel.org/r/20201020011406.1818918-1-natechancellor@gmail.com Signed-off-by: Will Deacon <will@kernel.org>
* kbuild: explicitly specify the build id styleBill Wendling2020-10-091-1/+1
| | | | | | | | | | ld's --build-id defaults to "sha1" style, while lld defaults to "fast". The build IDs are very different between the two, which may confuse programs that reference them. Signed-off-by: Bill Wendling <morbo@google.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
* kbuild: remove cc-option test of -Werror=date-timeMasahiro Yamada2020-09-251-1/+1
| | | | | | | | | | | The minimal compiler versions, GCC 4.9 and Clang 10 support this flag. Here is the godbolt: https://godbolt.org/z/xvjcMa Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Acked-by: Will Deacon <will@kernel.org>
* kbuild: remove cc-option test of -fno-strict-overflowMasahiro Yamada2020-09-251-1/+1
| | | | | | | | | | | The minimal compiler versions, GCC 4.9 and Clang 10 support this flag. Here is the godbolt: https://godbolt.org/z/odq8h9 Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Acked-by: Will Deacon <will@kernel.org>
* arch: vdso: add vdso linker script to 'targets' instead of extra-yMasahiro Yamada2020-09-071-1/+1
| | | | | | | | | The vdso linker script is preprocessed on demand. Adding it to 'targets' is enough to include the .cmd file. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Greentime Hu <green.hu@gmail.com>
* ARM64: vdso32: Install vdso32 from vdso_installStephen Boyd2020-08-211-1/+1
| | | | | | | | | | | | | Add the 32-bit vdso Makefile to the vdso_install rule so that 'make vdso_install' installs the 32-bit compat vdso when it is compiled. Fixes: a7f71a2c8903 ("arm64: compat: Add vDSO") Signed-off-by: Stephen Boyd <swboyd@chromium.org> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Acked-by: Will Deacon <will@kernel.org> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lore.kernel.org/r/20200818014950.42492-1-swboyd@chromium.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* Merge tag 'arm64-upstream' of ↵Linus Torvalds2020-08-031-1/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 and cross-arch updates from Catalin Marinas: "Here's a slightly wider-spread set of updates for 5.9. Going outside the usual arch/arm64/ area is the removal of read_barrier_depends() series from Will and the MSI/IOMMU ID translation series from Lorenzo. The notable arm64 updates include ARMv8.4 TLBI range operations and translation level hint, time namespace support, and perf. Summary: - Removal of the tremendously unpopular read_barrier_depends() barrier, which is a NOP on all architectures apart from Alpha, in favour of allowing architectures to override READ_ONCE() and do whatever dance they need to do to ensure address dependencies provide LOAD -> LOAD/STORE ordering. This work also offers a potential solution if compilers are shown to convert LOAD -> LOAD address dependencies into control dependencies (e.g. under LTO), as weakly ordered architectures will effectively be able to upgrade READ_ONCE() to smp_load_acquire(). The latter case is not used yet, but will be discussed further at LPC. - Make the MSI/IOMMU input/output ID translation PCI agnostic, augment the MSI/IOMMU ACPI/OF ID mapping APIs to accept an input ID bus-specific parameter and apply the resulting changes to the device ID space provided by the Freescale FSL bus. - arm64 support for TLBI range operations and translation table level hints (part of the ARMv8.4 architecture version). - Time namespace support for arm64. - Export the virtual and physical address sizes in vmcoreinfo for makedumpfile and crash utilities. - CPU feature handling cleanups and checks for programmer errors (overlapping bit-fields). - ACPI updates for arm64: disallow AML accesses to EFI code regions and kernel memory. - perf updates for arm64. - Miscellaneous fixes and cleanups, most notably PLT counting optimisation for module loading, recordmcount fix to ignore relocations other than R_AARCH64_CALL26, CMA areas reserved for gigantic pages on 16K and 64K configurations. - Trivial typos, duplicate words" Link: http://lkml.kernel.org/r/20200710165203.31284-1-will@kernel.org Link: http://lkml.kernel.org/r/20200619082013.13661-1-lorenzo.pieralisi@arm.com * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (82 commits) arm64: use IRQ_STACK_SIZE instead of THREAD_SIZE for irq stack arm64/mm: save memory access in check_and_switch_context() fast switch path arm64: sigcontext.h: delete duplicated word arm64: ptrace.h: delete duplicated word arm64: pgtable-hwdef.h: delete duplicated words bus: fsl-mc: Add ACPI support for fsl-mc bus/fsl-mc: Refactor the MSI domain creation in the DPRC driver of/irq: Make of_msi_map_rid() PCI bus agnostic of/irq: make of_msi_map_get_device_domain() bus agnostic dt-bindings: arm: fsl: Add msi-map device-tree binding for fsl-mc bus of/device: Add input id to of_dma_configure() of/iommu: Make of_map_rid() PCI agnostic ACPI/IORT: Add an input ID to acpi_dma_configure() ACPI/IORT: Remove useless PCI bus walk ACPI/IORT: Make iort_msi_map_rid() PCI agnostic ACPI/IORT: Make iort_get_device_domain IRQ domain agnostic ACPI/IORT: Make iort_match_node_callback walk the ACPI namespace for NC arm64: enable time namespace support arm64/vdso: Restrict splitting VVAR VMA arm64/vdso: Handle faults on timens page ...
| * arm64/vdso: Add time namespace pageAndrei Vagin2020-07-241-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allocate the time namespace page among VVAR pages. Provide __arch_get_timens_vdso_data() helper for VDSO code to get the code-relative position of VVARs on that special page. If a task belongs to a time namespace then the VVAR page which contains the system wide VDSO data is replaced with a namespace specific page which has the same layout as the VVAR page. That page has vdso_data->seq set to 1 to enforce the slow path and vdso_data->clock_mode set to VCLOCK_TIMENS to enforce the time namespace handling path. The extra check in the case that vdso_data->seq is odd, e.g. a concurrent update of the VDSO data is in progress, is not really affecting regular tasks which are not part of a time namespace as the task is spin waiting for the update to finish and vdso_data->seq to become even again. If a time namespace task hits that code path, it invokes the corresponding time getter function which retrieves the real VVAR page, reads host time and then adds the offset for the requested clock which is stored in the special VVAR page. The time-namespace page isn't allocated on !CONFIG_TIME_NAMESPACE, but vma is the same size, which simplifies criu/vdso migration between different kernel configs. Signed-off-by: Andrei Vagin <avagin@gmail.com> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Reviewed-by: Dmitry Safonov <dima@arista.com> Cc: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20200624083321.144975-4-avagin@gmail.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* | arm64: vdso32: Fix '--prefix=' value for newer versions of clangNathan Chancellor2020-07-231-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | Newer versions of clang only look for $(COMPAT_GCC_TOOLCHAIN_DIR)as [1], rather than $(COMPAT_GCC_TOOLCHAIN_DIR)$(CROSS_COMPILE_COMPAT)as, resulting in the following build error: $ make -skj"$(nproc)" ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- \ CROSS_COMPILE_COMPAT=arm-linux-gnueabi- LLVM=1 O=out/aarch64 distclean \ defconfig arch/arm64/kernel/vdso32/ ... /home/nathan/cbl/toolchains/llvm-binutils/bin/as: unrecognized option '-EL' clang-12: error: assembler command failed with exit code 1 (use -v to see invocation) make[3]: *** [arch/arm64/kernel/vdso32/Makefile:181: arch/arm64/kernel/vdso32/note.o] Error 1 ... Adding the value of CROSS_COMPILE_COMPAT (adding notdir to account for a full path for CROSS_COMPILE_COMPAT) fixes this issue, which matches the solution done for the main Makefile [2]. [1]: https://github.com/llvm/llvm-project/commit/3452a0d8c17f7166f479706b293caf6ac76ffd90 [2]: https://lore.kernel.org/lkml/20200721173125.1273884-1-maskray@google.com/ Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Cc: stable@vger.kernel.org Link: https://github.com/ClangBuiltLinux/linux/issues/1099 Link: https://lore.kernel.org/r/20200723041509.400450-1-natechancellor@gmail.com Signed-off-by: Will Deacon <will@kernel.org>
* arm64: compat: Remove 32-bit sigreturn code from the vDSOWill Deacon2020-06-233-71/+0
| | | | | | | | | The sigreturn code in the compat vDSO is unused. Remove it. Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso32: add CONFIG_THUMB2_COMPAT_VDSONick Desaulniers2020-06-101-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allow the compat vdso (32b) to be compiled as either THUMB2 (default) or ARM. For THUMB2, the register r7 is reserved for the frame pointer, but code in arch/arm64/include/asm/vdso/compat_gettimeofday.h uses r7. Explicitly set -fomit-frame-pointer, since unwinding through interworked THUMB2 and ARM is unreliable anyways. See also how CONFIG_UNWINDER_FRAME_POINTER cannot be selected for CONFIG_THUMB2_KERNEL for ARCH=arm. This also helps toolchains that differ in their implicit value if the choice of -f{no-}omit-frame-pointer is left unspecified, to not error on the use of r7. 2019 Q4 ARM AAPCS seeks to standardize the use of r11 as the reserved frame pointer register, but no production compiler that can compile the Linux kernel currently implements this. We're actively discussing such a transition with ARM toolchain developers currently. Reported-by: Luis Lozano <llozano@google.com> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Manoj Gupta <manojgupta@google.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Stephen Boyd <swboyd@google.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Dave Martin <Dave.Martin@arm.com> Link: https://static.docs.arm.com/ihi0042/i/aapcs32.pdf Link: https://bugs.chromium.org/p/chromium/issues/detail?id=1084372 Link: https://lore.kernel.org/r/20200608205711.109418-1-ndesaulniers@google.com Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso: Fix CFI directives in sigreturn trampolineWill Deacon2020-05-211-0/+3
| | | | | | | | | | | | | | | | | | | | | | Daniel reports that the .cfi_startproc is misplaced for the sigreturn trampoline, which causes LLVM's unwinder to misbehave: | I run into this with LLVM’s unwinder. | This combination was always broken. This prompted Dave to question our use of CFI directives more generally, and I ended up going down a rabbit hole trying to figure out how this very poorly documented stuff gets used. Move the CFI directives so that the "mysterious NOP" is included in the .cfi_{start,end}proc block and add a bunch of comments so that I can save myself another headache in future. Cc: Tamas Zsoldos <tamas.zsoldos@arm.com> Reported-by: Dave Martin <dave.martin@arm.com> Reported-by: Daniel Kiss <daniel.kiss@arm.com> Tested-by: Daniel Kiss <daniel.kiss@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso: Don't prefix sigreturn trampoline with a BTI C instructionWill Deacon2020-05-211-8/+8
| | | | | | | | | | | | | | | | | | | | For better or worse, GDB relies on the exact instruction sequence in the VDSO sigreturn trampoline in order to unwind from signals correctly. Commit c91db232da48 ("arm64: vdso: Convert to modern assembler annotations") unfortunately added a BTI C instruction to the start of __kernel_rt_sigreturn, which breaks this check. Thankfully, it's also not required, since the trampoline is called from a RET instruction when returning from the signal handler Remove the unnecessary BTI C instruction from __kernel_rt_sigreturn, and do the same for the 32-bit VDSO as well for good measure. Cc: Daniel Kiss <daniel.kiss@arm.com> Cc: Tamas Zsoldos <tamas.zsoldos@arm.com> Reviewed-by: Dave Martin <dave.martin@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Fixes: c91db232da48 ("arm64: vdso: Convert to modern assembler annotations") Signed-off-by: Will Deacon <will@kernel.org>
* Merge tag 'spdx-5.7-rc1' of ↵Linus Torvalds2020-04-031-0/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx Pull SPDX updates from Greg KH: "Here are three SPDX patches for 5.7-rc1. One fixes up the SPDX tag for a single driver, while the other two go through the tree and add SPDX tags for all of the .gitignore files as needed. Nothing too complex, but you will get a merge conflict with your current tree, that should be trivial to handle (one file modified by two things, one file deleted.) All three of these have been in linux-next for a while, with no reported issues other than the merge conflict" * tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx: ASoC: MT6660: make spdxcheck.py happy .gitignore: add SPDX License Identifier .gitignore: remove too obvious comments
| * .gitignore: add SPDX License IdentifierMasahiro Yamada2020-03-251-0/+1
| | | | | | | | | | | | | | Add SPDX License Identifier to all .gitignore files. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | Merge tag 'arm64-upstream' of ↵Linus Torvalds2020-03-311-15/+8
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: "The bulk is in-kernel pointer authentication, activity monitors and lots of asm symbol annotations. I also queued the sys_mremap() patch commenting the asymmetry in the address untagging. Summary: - In-kernel Pointer Authentication support (previously only offered to user space). - ARM Activity Monitors (AMU) extension support allowing better CPU utilisation numbers for the scheduler (frequency invariance). - Memory hot-remove support for arm64. - Lots of asm annotations (SYM_*) in preparation for the in-kernel Branch Target Identification (BTI) support. - arm64 perf updates: ARMv8.5-PMU 64-bit counters, refactoring the PMU init callbacks, support for new DT compatibles. - IPv6 header checksum optimisation. - Fixes: SDEI (software delegated exception interface) double-lock on hibernate with shared events. - Minor clean-ups and refactoring: cpu_ops accessor, cpu_do_switch_mm() converted to C, cpufeature finalisation helper. - sys_mremap() comment explaining the asymmetric address untagging behaviour" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (81 commits) mm/mremap: Add comment explaining the untagging behaviour of mremap() arm64: head: Convert install_el2_stub to SYM_INNER_LABEL arm64: Introduce get_cpu_ops() helper function arm64: Rename cpu_read_ops() to init_cpu_ops() arm64: Declare ACPI parking protocol CPU operation if needed arm64: move kimage_vaddr to .rodata arm64: use mov_q instead of literal ldr arm64: Kconfig: verify binutils support for ARM64_PTR_AUTH lkdtm: arm64: test kernel pointer authentication arm64: compile the kernel with ptrauth return address signing kconfig: Add support for 'as-option' arm64: suspend: restore the kernel ptrauth keys arm64: __show_regs: strip PAC from lr in printk arm64: unwind: strip PAC from kernel addresses arm64: mask PAC bits of __builtin_return_address arm64: initialize ptrauth keys for kernel booting task arm64: initialize and switch ptrauth kernel keys arm64: enable ptrauth earlier arm64: cpufeature: handle conflicts based on capability arm64: cpufeature: Move cpu capability helpers inside C file ...
| * | arm64: vdso32: Convert to modern assembler annotationsMark Brown2020-03-091-15/+8
| |/ | | | | | | | | | | | | | | | | | | | | In an effort to clarify and simplify the annotation of assembly functions new macros have been introduced. These replace ENTRY and ENDPROC with two different annotations for normal functions and those with unusual calling conventions. Use these for the compat VDSO, allowing us to drop the custom ARM_ENTRY() and ARM_ENDPROC() macros. Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* | arm64: vdso32: Enable Clang CompilationVincenzo Frascino2020-03-211-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Enable Clang Compilation for the vdso32 library. Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Nathan Chancellor <natechancellor@gmail.com> # build Tested-by: Stephen Boyd <swboyd@chromium.org> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lkml.kernel.org/r/20200320145351.32292-27-vincenzo.frascino@arm.com
* | arm64: vdso32: Include common headers in the vdso libraryVincenzo Frascino2020-03-211-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The vDSO library should only include the necessary headers required for a userspace library (UAPI and a minimal set of kernel headers). To make this possible it is necessary to isolate from the kernel headers the common parts that are strictly necessary to build the library. Refactor the vdso32 implementation to include common headers. Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lkml.kernel.org/r/20200320145351.32292-22-vincenzo.frascino@arm.com
* | arm64: vdso32: Code clean upVincenzo Frascino2020-03-211-12/+0
|/ | | | | | | | | | | | | | | | | The compat vdso library had some checks that are not anymore relevant. Remove the unused code from the compat vDSO library. Note: This patch is preparatory for a future one that will introduce asm/vdso/processor.h on arm64. Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/lkml/20200317122220.30393-19-vincenzo.frascino@arm.com Link: https://lkml.kernel.org/r/20200320145351.32292-19-vincenzo.frascino@arm.com
* kbuild: rename hostprogs-y/always to hostprogs/always-yMasahiro Yamada2020-02-041-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | In old days, the "host-progs" syntax was used for specifying host programs. It was renamed to the current "hostprogs-y" in 2004. It is typically useful in scripts/Makefile because it allows Kbuild to selectively compile host programs based on the kernel configuration. This commit renames like follows: always -> always-y hostprogs-y -> hostprogs So, scripts/Makefile will look like this: always-$(CONFIG_BUILD_BIN2C) += ... always-$(CONFIG_KALLSYMS) += ... ... hostprogs := $(always-y) $(always-m) I think this makes more sense because a host program is always a host program, irrespective of the kernel configuration. We want to specify which ones to compile by CONFIG options, so always-y will be handier. The "always", "hostprogs-y", "hostprogs-m" will be kept for backward compatibility for a while. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
* arm64: vdso32: Rename COMPATCC to CC_COMPATWill Deacon2019-10-071-13/+13
| | | | | | | | | For consistency with CROSS_COMPILE_COMPAT, mechanically rename COMPATCC to CC_COMPAT so that specifying aspects of the compat vDSO toolchain in the environment isn't needlessly confusing. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso32: Pass '--target' option to clang via VDSO_CAFLAGSWill Deacon2019-10-071-1/+5
| | | | | | | | | | | | | | | Directly passing the '--target' option to clang by appending to COMPATCC does not work if COMPATCC has been specified explicitly as an argument to Make unless the 'override' directive is used, which is ugly and different to what is done in the top-level Makefile. Move the '--target' option for clang out of COMPATCC and into VDSO_CAFLAGS, where it will be picked up when compiling and assembling the 32-bit vDSO under clang. Reported-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso32: Don't use KBUILD_CPPFLAGS unconditionallyWill Deacon2019-10-071-4/+2
| | | | | | | | | | | | | | | | KBUILD_CPPFLAGS is defined differently depending on whether the main compiler is clang or not. This means that it is not possible to build the compat vDSO with GCC if the rest of the kernel is built with clang. Define VDSO_CPPFLAGS directly to break this dependency and allow a clang kernel to build a compat vDSO with GCC: $ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- \ CROSS_COMPILE_COMPAT=arm-linux-gnueabihf- CC=clang \ COMPATCC=arm-linux-gnueabihf-gcc Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso32: Move definition of COMPATCC into vdso32/MakefileWill Deacon2019-10-071-0/+6
| | | | | | | | There's no need to export COMPATCC, so just define it locally in the vdso32/Makefile, which is the only place where it is used. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso32: Remove jump label config option in MakefileVincenzo Frascino2019-10-071-3/+0
| | | | | | | | | | | | | | The jump labels are not used in vdso32 since it is not possible to run runtime patching on them. Remove the configuration option from the Makefile. Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso32: Detect binutils support for dmb ishldVincenzo Frascino2019-10-071-0/+9
| | | | | | | | | | | | | | | | | Older versions of binutils (prior to 2.24) do not support the "ISHLD" option for memory barrier instructions, which leads to a build failure when assembling the vdso32 library. Add a compilation time mechanism that detects if binutils supports those instructions and configure the kernel accordingly. Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Will Deacon <will@kernel.org> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso32: Fix broken compat vDSO build warningsVincenzo Frascino2019-10-071-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The .config file and the generated include/config/auto.conf can end up out of sync after a set of commands since CONFIG_CROSS_COMPILE_COMPAT_VDSO is not updated correctly. The sequence can be reproduced as follows: $ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- defconfig [...] $ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- menuconfig [set CONFIG_CROSS_COMPILE_COMPAT_VDSO="arm-linux-gnueabihf-"] $ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- Which results in: arch/arm64/Makefile:62: CROSS_COMPILE_COMPAT not defined or empty, the compat vDSO will not be built even though the compat vDSO has been built: $ file arch/arm64/kernel/vdso32/vdso.so arch/arm64/kernel/vdso32/vdso.so: ELF 32-bit LSB pie executable, ARM, EABI5 version 1 (SYSV), dynamically linked, BuildID[sha1]=c67f6c786f2d2d6f86c71f708595594aa25247f6, stripped A similar case that involves changing the configuration parameter multiple times can be reconducted to the same family of problems. Remove the use of CONFIG_CROSS_COMPILE_COMPAT_VDSO altogether and instead rely on the cross-compiler prefix coming from the environment via CROSS_COMPILE_COMPAT, much like we do for the rest of the kernel. Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Will Deacon <will@kernel.org> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso: Cleanup MakefilesVincenzo Frascino2019-07-221-5/+5
| | | | | | | | | | | | | | | | | The recent changes to the vdso library for arm64 and the introduction of the compat vdso library have generated some misalignment in the Makefiles. Cleanup the Makefiles for vdso and vdso32 libraries: * Removing unused rules. * Unifying the displayed compilation messages. * Simplifying the generic library inclusion path for arm64 vdso. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
* arm64: vdso: fix flip/flop vdso build bugNaohiro Aota2019-07-221-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Running "make" on an already compiled kernel tree will rebuild the kernel even without any modifications: $ make ARCH=arm64 CROSS_COMPILE=/usr/bin/aarch64-unknown-linux-gnu- arch/arm64/Makefile:58: CROSS_COMPILE_COMPAT not defined or empty, the compat vDSO will not be built CALL scripts/checksyscalls.sh CALL scripts/atomic/check-atomics.sh VDSOCHK arch/arm64/kernel/vdso/vdso.so.dbg VDSOSYM include/generated/vdso-offsets.h CHK include/generated/compile.h CC arch/arm64/kernel/signal.o CC arch/arm64/kernel/vdso.o CC arch/arm64/kernel/signal32.o LD arch/arm64/kernel/vdso/vdso.so.dbg OBJCOPY arch/arm64/kernel/vdso/vdso.so AS arch/arm64/kernel/vdso/vdso.o AR arch/arm64/kernel/vdso/built-in.a AR arch/arm64/kernel/built-in.a GEN .version CHK include/generated/compile.h UPD include/generated/compile.h CC init/version.o AR init/built-in.a LD vmlinux.o This is the same bug fixed in commit 92a4728608a8 ("x86/boot: Fix if_changed build flip/flop bug"). We cannot use two "if_changed" in one target. Fix this build bug by merging two commands into one function. Fixes: a7f71a2c8903 ("arm64: compat: Add vDSO") Fixes: 28b1a824a4f4 ("arm64: vdso: Substitute gettimeofday() with C implementation") Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Co-developed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> [will: merged in compat fix from Vincenzo and made rule names consistent] Signed-off-by: Will Deacon <will@kernel.org>
* kbuild: add --hash-style= and --build-id unconditionallyMasahiro Yamada2019-07-171-2/+2
| | | | | | | | | | As commit 1e0221374e30 ("mips: vdso: drop unnecessary cc-ldoption") explained, these flags are supported by the minimal required version of binutils. They are supported by ld.lld too. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Tested-by: Nathan Chancellor <natechancellor@gmail.com>
* arm64: compat: Add vDSOVincenzo Frascino2019-06-227-0/+425
Provide the arm64 compat (AArch32) vDSO in kernel/vdso32 in a similar way to what happens in kernel/vdso. The compat vDSO leverages on an adaptation of the arm architecture code with few changes: - Use of lib/vdso for gettimeofday - Implement a syscall based fallback - Introduce clock_getres() for the compat library - Implement trampolines - Implement elf note To build the compat vDSO a 32 bit compiler is required and needs to be specified via CONFIG_CROSS_COMPILE_COMPAT_VDSO. The code is not yet enabled as other prerequisites are missing. Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Shijith Thotton <sthotton@marvell.com> Tested-by: Andre Przywara <andre.przywara@arm.com> Cc: linux-arch@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-mips@vger.kernel.org Cc: linux-kselftest@vger.kernel.org Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Russell King <linux@armlinux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paul.burton@mips.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Mark Salyzyn <salyzyn@android.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Huw Davies <huw@codeweavers.com> Link: https://lkml.kernel.org/r/20190621095252.32307-11-vincenzo.frascino@arm.com