• Tom Saeger's avatar
    sh: define RUNTIME_DISCARD_EXIT · c1c551be
    Tom Saeger authored
    sh vmlinux fails to link with GNU ld < 2.40 (likely < 2.36) since
    commit 99cb0d91 ("arch: fix broken BuildID for arm64 and riscv").
    
    This is similar to fixes for powerpc and s390:
    commit 4b9880db ("powerpc/vmlinux.lds: Define RUNTIME_DISCARD_EXIT").
    commit a494398b ("s390: define RUNTIME_DISCARD_EXIT to fix link error
    with GNU ld < 2.36").
    
      $ sh4-linux-gnu-ld --version | head -n1
      GNU ld (GNU Binutils for Debian) 2.35.2
    
      $ make ARCH=sh CROSS_COMPILE=sh4-linux-gnu- microdev_defconfig
      $ make ARCH=sh CROSS_COMPILE=sh4-linux-gnu-
    
      `.exit.text' referenced in section `__bug_table' of crypto/algboss.o:
      defined in discarded section `.exit.text' of crypto/algboss.o
      `.exit.text' referenced in section `__bug_table' of
      drivers/char/hw_random/core.o: defined in discarded section
      `.exit.text' of drivers/char/hw_random/core.o
      make[2]: *** [scripts/Makefile.vmlinux:34: vmlinux] Error 1
      make[1]: *** [Makefile:1252: vmlinux] Error 2
    
    arch/sh/kernel/vmlinux.lds.S keeps EXIT_TEXT:
    
    	/*
    	 * .exit.text is discarded at runtime, not link time, to deal with
    	 * references from __bug_table
    	 */
    	.exit.text : AT(ADDR(.exit.text)) { EXIT_TEXT }
    
    However, EXIT_TEXT is thrown away by
    DISCARD(include/asm-generic/vmlinux.lds.h) because
    sh does not define RUNTIME_DISCARD_EXIT.
    
    GNU ld 2.40 does not have this issue and builds fine.
    This corresponds with Masahiro's comments in a494398b:
    "Nathan [Chancellor] also found that binutils
    commit 21401fc7bf67 ("Duplicate output sections in scripts") cured this
    issue, so we cannot reproduce it with binutils 2.36+, but it is better
    to not rely on it."
    
    Link: https://lkml.kernel.org/r/9166a8abdc0f979e50377e61780a4bba1dfa2f52.1674518464.git.tom.saeger@oracle.com
    Fixes: 99cb0d91 ("arch: fix broken BuildID for arm64 and riscv")
    Link: https://lore.kernel.org/all/Y7Jal56f6UBh1abE@dev-arch.thelio-3990X/
    Link: https://lore.kernel.org/all/20230123194218.47ssfzhrpnv3xfez@oracle.com/Signed-off-by: default avatarTom Saeger <tom.saeger@oracle.com>
    Tested-by: default avatarJohn Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
    Cc: Ard Biesheuvel <ardb@kernel.org>
    Cc: Arnd Bergmann <arnd@arndb.de>
    Cc: Christoph Hellwig <hch@lst.de>
    Cc: Dennis Gilmore <dennis@ausil.us>
    Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    Cc: Masahiro Yamada <masahiroy@kernel.org>
    Cc: Naresh Kamboju <naresh.kamboju@linaro.org>
    Cc: Nathan Chancellor <nathan@kernel.org>
    Cc: Palmer Dabbelt <palmer@rivosinc.com>
    Cc: Rich Felker <dalias@libc.org>
    Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    c1c551be
vmlinux.lds.S 1.53 KB