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    SubjectRe: [PATCH] scripts/gdb: Handle split debug
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    On 31.07.19 17:44, Doug Anderson wrote:
    > Hi,
    >
    > On Wed, Jul 31, 2019 at 7:24 AM Jan Kiszka <jan.kiszka@siemens.com> wrote:
    >>
    >> On 31.07.19 01:40, Douglas Anderson wrote:
    >>> Some systems (like Chrome OS) may use "split debug" for kernel
    >>> modules. That means that the debug symbols are in a different file
    >>> than the main elf file. Let's handle that by also searching for debug
    >>> symbols that end in ".ko.debug".
    >>
    >> Is this split-up depending on additional kernel patches, is this already
    >> possible with mainline, or is this purely a packaging topic? Wondering because
    >> of testability in case it's downstream-only.
    >
    > It is a packaging topic. You can take a normal elf file and split the
    > debug out of it using objcopy. Try "man objcopy" and then take a look
    > at the "--only-keep-debug" option. It'll give you a whole recipe for
    > doing splitdebug. The suffix used for the debug symbols is arbitrary.
    > If people have other another suffix besides ".ko.debug" then we could
    > presumably support that too...
    >
    > For portage (which is the packaging system used by Chrome OS) split
    > debug is supported by default (and the suffix is .ko.debug). ...and
    > so in Chrome OS we always get the installed elf files stripped and
    > then the symbols stashed away.
    >
    > At the moment we don't actually use the normal portage magic to do
    > this for the kernel though since it affects our ability to get good
    > stack dumps in the kernel. We instead pass a script as "strip" [1].
    >
    >
    > [1] https://chromium.googlesource.com/chromiumos/overlays/chromiumos-overlay/+/refs/heads/master/eclass/cros-kernel/strip_splitdebug
    >
    >
    > -Doug
    >

    Thanks, makes perfect sense to me. You may add my

    Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>

    Jan

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