On 07.03.2023 15:23, Juergen Gross wrote: > On 07.03.23 15:18, Jan Beulich wrote: >> On 07.03.2023 15:04, Juergen Gross wrote: >>> On 07.03.23 11:41, Jan Beulich wrote: >>>> On 07.03.2023 07:32, Juergen Gross wrote: >>>>> --- a/xen/Kconfig.debug >>>>> +++ b/xen/Kconfig.debug >>>>> @@ -15,8 +15,11 @@ config DEBUG_INFO >>>>> bool "Compile Xen with debug info" >>>>> default DEBUG >>>>> ---help--- >>>>> - If you say Y here the resulting Xen will include debugging info >>>>> - resulting in a larger binary image. >>>>> + Say Y here if you want to build Xen with debug information. This >>>>> + information is needed e.g. for doing crash dump analysis of the >>>>> + hypervisor via the "crash" tool. >>>>> + Saying Y will increase the size of xen-syms and the built EFI >>>>> + binary. >>>> >>>> Largely fine with me, just one question: Why do you mention xen-syms by >>>> name, but then verbally describe xen.efi? And since, unlike for xen-syms, >>> >>> For xen-syms I couldn't find an easily understandable wording. I'd be fine >>> with just saying "xen.efi". >>> >>>> this affects the installed binary actually used for booting (which may >>>> be placed on a space constrained partition), it may be prudent to >>>> mention INSTALL_EFI_STRIP here (as a way to reduce the binary size of >>>> what ends up on the EFI partition, even if that wouldn't affect the >>>> "normal" way of putting the binary on the EFI partition - people would >>>> still need to take care of that in their distros). >>> >>> What about adding a related Kconfig option instead? >> >> How would a Kconfig option possibly affect this? You want debug info >> in the xen.efi in its standard install location (outside of the EFI >> partition); or else if you don't want it there why would you want it >> in xen-syms? It is the step of populating the EFI partition from the >> standard install location where some equivalent of INSTALL_EFI_STRIP >> would come into play. That step is done outside of Xen's build >> system and hence outside of any Kconfig control. > > We have 2 binaries for the non-EFI hypervisor (xen-syms and xen[.gz]). > Why can't we have the same for EFI? E.g. xen-syms.efi and xen.efi. > The former would have the debug-info, the latter could be installed > into the EFI partition.
I view the two-binaries model of the non-EFI case as merely an implementation detail; it just so happens that there's little point in mkelf32 retaining debug info. I therefore don't view it as very reasonable to artificially introduce yet another binary. Another thing would be if there was a way to produce a binary without debug info accompanied by a separate file holding just the debug info. Yet I'm unaware of such being possible with PE/COFF binaries. But yes - technically this might be an option (although, just to mention it, I'm having a vague recollection of there being an issue with this, but I can't say what this might be, plus it is easily possible that I'm misremembering or mixing up things). Jan
