Messages in this thread | | | From | Alex Ghiti <> | Subject | Re: [PATCH v5 2/4] riscv: Introduce CONFIG_RELOCATABLE | Date | Thu, 11 Jun 2020 15:43:56 -0400 |
| |
Hi Jerome,
Le 6/10/20 à 10:10 AM, Jerome Forissier a écrit : > On 6/7/20 9:59 AM, Alexandre Ghiti wrote: > [...] > >> +config RELOCATABLE >> + bool >> + depends on MMU >> + help >> + This builds a kernel as a Position Independent Executable (PIE), >> + which retains all relocation metadata required to relocate the >> + kernel binary at runtime to a different virtual address than the >> + address it was linked at. >> + Since RISCV uses the RELA relocation format, this requires a >> + relocation pass at runtime even if the kernel is loaded at the >> + same address it was linked at. > Is this true? I thought that the GNU linker would write the "proper" > values by default, contrary to the LLVM linker (ld.lld) which would need > a special flag: --apply-dynamic-relocs (by default the relocated places > are set to zero). At least, it is my experience with Aarch64 on a > different project. So, sorry if I'm talking nonsense here -- I have not > looked at the details. > >
It seems that you're right, at least for aarch64 since they specifically specify the --no-apply-dynamic-relocs option. I retried to boot without relocating at runtime, and it fails on riscv. Can this be arch specific ?
Thanks,
Alex
| |