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    SubjectRe: [PATCH] kexec_file: Drop weak attribute from arch_kexec_apply_relocations[_add]
    On Wed, 18 May 2022 23:48:28 +0530 "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> wrote:

    > Since commit d1bcae833b32f1 ("ELF: Don't generate unused section
    > symbols") [1], binutils (v2.36+) started dropping section symbols that
    > it thought were unused. This isn't an issue in general, but with
    > kexec_file.c, gcc is placing kexec_arch_apply_relocations[_add] into a
    > separate .text.unlikely section and the section symbol ".text.unlikely"
    > is being dropped. Due to this, recordmcount is unable to find a non-weak
    > symbol in .text.unlikely to generate a relocation record against.
    >
    > Address this by dropping the weak attribute from these functions:
    > - arch_kexec_apply_relocations() is not overridden by any architecture
    > today, so just drop the weak attribute.
    > - arch_kexec_apply_relocations_add() is only overridden by x86 and s390.
    > Retain the function prototype for those and move the weak
    > implementation into the header as a static inline for other
    > architectures.
    >
    > ...
    >

    Sigh. This patch demonstrates why I like __weak :<

    > --- a/include/linux/kexec.h
    > +++ b/include/linux/kexec.h
    > @@ -229,6 +225,30 @@ extern int crash_exclude_mem_range(struct crash_mem *mem,
    > unsigned long long mend);
    > extern int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
    > void **addr, unsigned long *sz);
    > +
    > +#if defined(CONFIG_X86_64) || defined(CONFIG_S390)

    Let's avoid listing the architectures here? Better to add

    select ARCH_HAVE_ARCH_KEXEC_APPLY_RELOCATIONS_ADD

    to arch/<arch>/Kconfig?

    Please cc me on any additional work on this.

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