On 31.07.19 17:44, Doug Anderson wrote: > Hi, > > On Wed, Jul 31, 2019 at 7:24 AM Jan Kiszka <jan.kis...@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.kis...@siemens.com> Jan -- Siemens AG, Corporate Technology, CT RDA IOT SES-DE Corporate Competence Center Embedded Linux
