On Mon 2024-10-14 20:19:32, Ard Biesheuvel wrote: > On Mon, 14 Oct 2024 at 20:10, Linus Torvalds > <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: > > > > On Mon, 14 Oct 2024 at 10:44, Ard Biesheuvel <ardb@xxxxxxxxxx> wrote: > > > > > > We have this code in arch/x86/Makefile.postlink: > > > > > > quiet_cmd_strip_relocs = RSTRIP $@ > > > cmd_strip_relocs = \ > > > $(OBJCOPY) --remove-section='.rel.*' --remove-section='.rel__*' \ > > > --remove-section='.rela.*' --remove-section='.rela__*' $@ > > > > > > Of course, that could easily be fixed, I was just being cautious in > > > case there is other, out-of-tree tooling for live patch or kexec etc > > > that has similar assumptions wrt section names. > > > > I'd actually much rather just make strip_relocs not have that "." and > > "__" pattern at all, and just say "we strip all sections that start > > with '.rel'". > > > > And then we make the rule that we do *not* create sections named ".rel*". > > > > That seems like a much simpler rule, and would seem to simplify > > strip_relocs too, which would just become > > > > $(OBJCOPY) --remove-section='.rel*' $@ > > > > (We seem to have three different copies of that complex pattern with > > .rel vs .rela and "." vs "__" - it's in s390, riscv, and x86. So we'd > > do that simplification in three places) > > > > IOW, I'd much rather make our section rules simpler rather than more complex. > > > > Of course, if there is some active and acute problem report with this > > thing, we might not have that option, but in the absence of any > > *known* issue with just simplifying things, I'd rather do that. > > > > I don't disagree with any of this. CC'ing folks working on live patch > in case they have any insights. The livepatching specific sections use the name pattern: .klp.rela.objname.section_name They are generated by a post processing of the livepatch module. The code is not upstream at the moment. It is implemented by some out-of-tree tools which are used to build the livepatches. More details can be found in Documentation/livepatch/module-elf-format.rst Best Regards, Petr
