kernel.git/arch/riscv/Makefile, branch linux-5.4.y

riscv: disable generation of unwind tables

2023-02-22T11:50:28Z

commit 2f394c0e7d1129a35156e492bc8f445fb20f43ac upstream. GCC 13 will enable -fasynchronous-unwind-tables by default on riscv. In the kernel, we don't have any use for unwind tables yet, so disable them. More importantly, the .eh_frame section brings relocations (R_RISC_32_PCREL, R_RISCV_SET{6,8,16}, R_RISCV_SUB{6,8,16}) into modules that we are not prepared to handle. Signed-off-by: Andreas Schwab Link: https://lore.kernel.org/r/mvmzg9xybqu.fsf@suse.de Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt Signed-off-by: Greg Kroah-Hartman

riscv: Pass -mno-relax only on lld < 15.0.0

2022-10-26T11:22:15Z

commit 3cebf80e9a0d3adcb174053be32c88a640b3344b upstream. lld since llvm:6611d58f5bbc ("[ELF] Relax R_RISCV_ALIGN"), which will be included in the 15.0.0 release, has implemented some RISC-V linker relaxation. -mno-relax is no longer needed in KBUILD_CFLAGS/KBUILD_AFLAGS to suppress R_RISCV_ALIGN which older lld can not handle: ld.lld: error: capability.c:(.fixup+0x0): relocation R_RISCV_ALIGN requires unimplemented linker relaxation; recompile with -mno-relax but the .o is already compiled with -mno-relax Signed-off-by: Fangrui Song Link: https://lore.kernel.org/r/20220710071117.446112-1-maskray@google.com/ Link: https://lore.kernel.org/r/20220918092933.19943-1-palmer@rivosinc.com Reviewed-by: Nick Desaulniers Tested-by: Nick Desaulniers Tested-by: Nathan Chancellor Tested-by: Conor Dooley Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt Signed-off-by: Greg Kroah-Hartman

riscv: add as-options for modules with assembly compontents

2022-07-29T15:14:08Z

commit c1f6eff304e4dfa4558b6a8c6b2d26a91db6c998 upstream. When trying to load modules built for RISC-V which include assembly files the kernel loader errors with "unexpected relocation type 'R_RISCV_ALIGN'" due to R_RISCV_ALIGN relocations being generated by the assembler. The R_RISCV_ALIGN relocations can be removed at the expense of code space by adding -mno-relax to gcc and as. In commit 7a8e7da42250138 ("RISC-V: Fixes to module loading") -mno-relax is added to the build variable KBUILD_CFLAGS_MODULE. See [1] for more info. The issue is that when kbuild builds a .S file, it invokes gcc with the -mno-relax flag, but this is not being passed through to the assembler. Adding -Wa,-mno-relax to KBUILD_AFLAGS_MODULE ensures that the assembler is invoked correctly. This may have now been fixed in gcc[2] and this addition should not stop newer gcc and as from working. [1] https://github.com/riscv/riscv-elf-psabi-doc/issues/183 [2] https://github.com/gcc-mirror/gcc/commit/3b0a7d624e64eeb81e4d5e8c62c46d86ef521857 Signed-off-by: Ben Dooks Reviewed-by: Bin Meng Link: https://lore.kernel.org/r/20220529152200.609809-1-ben.dooks@codethink.co.uk Fixes: ab1ef68e5401 ("RISC-V: Add sections of PLT and GOT for kernel module") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt Signed-off-by: Greg Kroah-Hartman

riscv: fix build with binutils 2.38

2022-02-16T11:52:49Z

commit 6df2a016c0c8a3d0933ef33dd192ea6606b115e3 upstream. From version 2.38, binutils default to ISA spec version 20191213. This means that the csr read/write (csrr*/csrw*) instructions and fence.i instruction has separated from the `I` extension, become two standalone extensions: Zicsr and Zifencei. As the kernel uses those instruction, this causes the following build failure: CC arch/riscv/kernel/vdso/vgettimeofday.o <>/arch/riscv/include/asm/vdso/gettimeofday.h: Assembler messages: <>/arch/riscv/include/asm/vdso/gettimeofday.h:71: Error: unrecognized opcode `csrr a5,0xc01' <>/arch/riscv/include/asm/vdso/gettimeofday.h:71: Error: unrecognized opcode `csrr a5,0xc01' <>/arch/riscv/include/asm/vdso/gettimeofday.h:71: Error: unrecognized opcode `csrr a5,0xc01' <>/arch/riscv/include/asm/vdso/gettimeofday.h:71: Error: unrecognized opcode `csrr a5,0xc01' The fix is to specify those extensions explicitely in -march. However as older binutils version do not support this, we first need to detect that. Signed-off-by: Aurelien Jarno Tested-by: Alexandre Ghiti Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt Signed-off-by: Greg Kroah-Hartman

riscv: Use -mno-relax when using lld linker

2021-06-18T07:58:58Z

[ Upstream commit ec3a5cb61146c91f0f7dcec8b7e7157a4879a9ee ] lld does not implement the RISCV relaxation optimizations like GNU ld therefore disable it when building with lld, Also pass it to assembler when using external GNU assembler ( LLVM_IAS != 1 ), this ensures that relevant assembler option is also enabled along. if these options are not used then we see following relocations in objects 0000000000000000 R_RISCV_ALIGN *ABS*+0x0000000000000002 These are then rejected by lld ld.lld: error: capability.c:(.fixup+0x0): relocation R_RISCV_ALIGN requires unimplemented linker relaxation; recompile with -mno-relax but the .o is already compiled with -mno-relax Signed-off-by: Khem Raj Reviewed-by: Nathan Chancellor Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin

Merge tag 'kbuild-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2019-09-20T15:36:47Z

Pull Kbuild updates from Masahiro Yamada: - add modpost warn exported symbols marked as 'static' because 'static' and EXPORT_SYMBOL is an odd combination - break the build early if gold linker is used - optimize the Bison rule to produce .c and .h files by a single pattern rule - handle PREEMPT_RT in the module vermagic and UTS_VERSION - warn CONFIG options leaked to the user-space except existing ones - make single targets work properly - rebuild modules when module linker scripts are updated - split the module final link stage into scripts/Makefile.modfinal - fix the missed error code in merge_config.sh - improve the error message displayed on the attempt of the O= build in unclean source tree - remove 'clean-dirs' syntax - disable -Wimplicit-fallthrough warning for Clang - add CONFIG_CC_OPTIMIZE_FOR_SIZE_O3 for ARC - remove ARCH_{CPP,A,C}FLAGS variables - add $(BASH) to run bash scripts - change *CFLAGS_.o to take the relative path to $(obj) instead of the basename - stop suppressing Clang's -Wunused-function warnings when W=1 - fix linux/export.h to avoid genksyms calculating CRC of trimmed exported symbols - misc cleanups * tag 'kbuild-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (63 commits) genksyms: convert to SPDX License Identifier for lex.l and parse.y modpost: use __section in the output to *.mod.c modpost: use MODULE_INFO() for __module_depends export.h, genksyms: do not make genksyms calculate CRC of trimmed symbols export.h: remove defined(__KERNEL__), which is no longer needed kbuild: allow Clang to find unused static inline functions for W=1 build kbuild: rename KBUILD_ENABLE_EXTRA_GCC_CHECKS to KBUILD_EXTRA_WARN kbuild: refactor scripts/Makefile.extrawarn merge_config.sh: ignore unwanted grep errors kbuild: change *FLAGS_.o to take the path relative to $(obj) modpost: add NOFAIL to strndup modpost: add guid_t type definition kbuild: add $(BASH) to run scripts with bash-extension kbuild: remove ARCH_{CPP,A,C}FLAGS kbuild,arc: add CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3 for ARC kbuild: Do not enable -Wimplicit-fallthrough for clang for now kbuild: clean up subdir-ymn calculation in Makefile.clean kbuild: remove unneeded '+' marker from cmd_clean kbuild: remove clean-dirs syntax kbuild: check clean srctree even earlier ...

riscv: Add perf callchain support

2019-09-04T19:43:00Z

This patch add support for perf callchain sampling on riscv platforms. The return address of leaf function is retrieved from pt_regs as it is not saved in the outmost frame. Signed-off-by: Mao Han Cc: Paul Walmsley Cc: Greentime Hu Cc: Palmer Dabbelt Cc: linux-riscv Cc: Christoph Hellwig Cc: Guo Ren Tested-by: Greentime Hu [paul.walmsley@sifive.com: fixed some 'checkpatch.pl --strict' issues; fixed patch description spelling] Signed-off-by: Paul Walmsley

riscv: add arch/riscv/Kbuild

2019-08-31T00:34:00Z

Use the standard obj-y form to specify the sub-directories under arch/riscv/. No functional change intended. Signed-off-by: Masahiro Yamada Signed-off-by: Paul Walmsley

kbuild: rebuild modules when module linker scripts are updated

2019-08-21T12:05:21Z

Currently, the timestamp of module linker scripts are not checked. Add them to the dependency of modules so they are correctly rebuilt. Signed-off-by: Masahiro Yamada

riscv: drop unneeded -Wall addition

2019-07-17T01:25:10Z

The top level Makefile adds -Wall globally: KBUILD_CFLAGS := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \ For riscv, I see two "-Wall" added for compiling each object. Signed-off-by: Masahiro Yamada