> On 18. Apr 2023, at 15:20, Gerd Hoffmann <kra...@redhat.com> wrote: > > On Tue, Apr 18, 2023 at 01:59:43PM +0200, Ard Biesheuvel wrote: >> On Tue, 18 Apr 2023 at 13:52, Gerd Hoffmann <kra...@redhat.com> wrote: >>> >>> Seems to work fine on fedora 37, even without adding --relax, maybe this >>> is enabled by default (there is a --no-relax switch after all). I'll go >>> try older distros / compilers / binutils too. >>> >>> What would be the failure mode? Errors on ELF -> PE conversion because >>> a GOT is present? Or will things break at runtime? >>> >> >> The problem here is that we rely on --emit-relocs to get at the >> relocations in the binary, in order to convert the absolute ones into >> PE/COFF relocations. >> >> However, --emit-relocs did not use to cover the GOT, as those are >> added at the end by the linker and not by the compiler. So if the GOT >> is non-empty, the resulting PE executable will be corrupt. > > So no build error. And at runtime probably random effects, depending on > whenever the execution path happens to hit a bad relocation or not. So > compile + boot testing doesn't cut it. Lovely. > > So, what can I do instead? Check **/DEBUG/*.debug and see whenever a > .got section is present? > >> Of course, the answer here is to dump GenFw altogether for ELF to PE >> conversion, and implement something that consumes the dynamic >> relocations generated when linking in PIE mode. > > Marvin's ImageTool is exactly that I think ...
Not quite, we actually didn't change anything about PIE vs non-PIE yet (X64 is PIE, rest is non-PIE). Though that was on the "long-term TODO" for sure. There are many other advantages though and if you're looking for an alternative to GenFw, I'm still happy to discuss things right now. As I develop this as part of a thesis and its deadline is in July, any efforts past that heavily depend on the workload at whatever job I will end up in. :) Best regards, Marvin > > take care, > Gerd > -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#103164): https://edk2.groups.io/g/devel/message/103164 Mute This Topic: https://groups.io/mt/98257896/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
