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    Subject[PATCH v2 14/20] elf: introduce NT_VMCORE_PAD type
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    The NT_VMCORE_PAD type is introduced to make both crash_notes buffer
    and vmcoreinfo_note buffer satisfy mmap()'s page-size boundary
    requirement by filling them with this note type.

    The purpose of this type is just to align the buffer in page-size
    boundary; it has no meaning in contents, which are fully filled with
    zero.

    This note type belongs to "VMCOREINFO" name space and the type in this
    name space is 7. The reason why the numbers from 1 to 5 is not chosen
    is that for the ones from 1 to 4, there are the corresponding note
    types using the same number in "CORE" name space, and crash utility
    and makedumpfile don't distinguish note types by name space at all;
    for the remaining 5, this has somehow not been used since v2.4.0
    kernel despite the fact that NT_AUXV is defined as 6. It looks that it
    avoids some dependency to 5. Here simply 5 is not chosen for
    conservative viewpoint.

    By this change, gdb and binutils work well without any change, but
    makedumpfile and crash utility need their changes to distinguish two
    note types in "VMCOREINFO" name space.

    Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
    ---

    include/uapi/linux/elf.h | 1 +
    1 files changed, 1 insertions(+), 0 deletions(-)

    diff --git a/include/uapi/linux/elf.h b/include/uapi/linux/elf.h
    index b869904..9753e4c 100644
    --- a/include/uapi/linux/elf.h
    +++ b/include/uapi/linux/elf.h
    @@ -402,6 +402,7 @@ typedef struct elf64_shdr {
    * Notes exported from /proc/vmcore, belonging to "VMCOREINFO" name.
    */
    #define NT_VMCORE_DEBUGINFO 0 /* vmcore system kernel's debuginfo */
    +#define NT_VMCORE_PAD 7 /* vmcore padding of note segments */

    /* Note header in a PT_NOTE section */
    typedef struct elf32_note {


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