On 03/01/21 at 09:47am, Stephen Boyd wrote:
> We can use the vmlinux_build_id() helper here now instead of open coding
> it. This consolidates code and possibly avoids calculating the build ID
> twice in the case of a crash with a stacktrace.
> 
> Cc: Jiri Olsa <[email protected]>
> Cc: Alexei Starovoitov <[email protected]>
> Cc: Jessica Yu <[email protected]>
> Cc: Evan Green <[email protected]>
> Cc: Hsin-Yi Wang <[email protected]>
> Cc: Dave Young <[email protected]>
> Cc: Baoquan He <[email protected]>
> Cc: Vivek Goyal <[email protected]>
> Cc: <[email protected]>
> Signed-off-by: Stephen Boyd <[email protected]>
> ---
>  kernel/crash_core.c | 46 ++++++++-------------------------------------
>  1 file changed, 8 insertions(+), 38 deletions(-)
> 
> diff --git a/kernel/crash_core.c b/kernel/crash_core.c
> index 825284baaf46..07d3e1109a8c 100644
> --- a/kernel/crash_core.c
> +++ b/kernel/crash_core.c
> @@ -4,6 +4,7 @@
>   * Copyright (C) 2002-2004 Eric Biederman  <[email protected]>
>   */
>  
> +#include <linux/buildid.h>
>  #include <linux/crash_core.h>
>  #include <linux/utsname.h>
>  #include <linux/vmalloc.h>
> @@ -378,51 +379,20 @@ phys_addr_t __weak paddr_vmcoreinfo_note(void)
>  }
>  EXPORT_SYMBOL(paddr_vmcoreinfo_note);
>  
> -#define NOTES_SIZE (&__stop_notes - &__start_notes)
> -#define BUILD_ID_MAX SHA1_DIGEST_SIZE
> -#define NT_GNU_BUILD_ID 3
> -
> -struct elf_note_section {
> -     struct elf_note n_hdr;
> -     u8 n_data[];
> -};
> -
>  /*
>   * Add build ID from .notes section as generated by the GNU ld(1)
>   * or LLVM lld(1) --build-id option.
>   */
>  static void add_build_id_vmcoreinfo(void)
>  {
> -     char build_id[BUILD_ID_MAX * 2 + 1];
> -     int n_remain = NOTES_SIZE;
> -
> -     while (n_remain >= sizeof(struct elf_note)) {
> -             const struct elf_note_section *note_sec =
> -                     &__start_notes + NOTES_SIZE - n_remain;
> -             const u32 n_namesz = note_sec->n_hdr.n_namesz;
> -
> -             if (note_sec->n_hdr.n_type == NT_GNU_BUILD_ID &&
> -                 n_namesz != 0 &&
> -                 !strcmp((char *)&note_sec->n_data[0], "GNU")) {
> -                     if (note_sec->n_hdr.n_descsz <= BUILD_ID_MAX) {
> -                             const u32 n_descsz = note_sec->n_hdr.n_descsz;
> -                             const u8 *s = &note_sec->n_data[n_namesz];
> -
> -                             s = PTR_ALIGN(s, 4);
> -                             bin2hex(build_id, s, n_descsz);
> -                             build_id[2 * n_descsz] = '\0';
> -                             VMCOREINFO_BUILD_ID(build_id);
> -                             return;
> -                     }
> -                     pr_warn("Build ID is too large to include in 
> vmcoreinfo: %u > %u\n",
> -                             note_sec->n_hdr.n_descsz,
> -                             BUILD_ID_MAX);
> -                     return;
> -             }
> -             n_remain -= sizeof(struct elf_note) +
> -                     ALIGN(note_sec->n_hdr.n_namesz, 4) +
> -                     ALIGN(note_sec->n_hdr.n_descsz, 4);
> +     const char *build_id = vmlinux_build_id();

It's strange that I can only see the cover letter and this patch 7,
couldn't find the patch where vmlinux_build_id() is introduced in lkml.

> +
> +     if (build_id[0] == '\0') {
> +             pr_warn("Build ID cannot be included in vmcoreinfo\n");
> +             return;
>       }
> +
> +     VMCOREINFO_BUILD_ID(build_id);
>  }
>  
>  static int __init crash_save_vmcoreinfo_init(void)
> -- 
> https://chromeos.dev
> 
> 
> _______________________________________________
> kexec mailing list
> [email protected]
> http://lists.infradead.org/mailman/listinfo/kexec
> 

Reply via email to