Re: [PATCH] riscv/kexec_file: Handle R_RISCV_64 in purgatory relocator
From: Björn Töpel
Date: Wed Mar 26 2025 - 13:04:38 EST
Yao Zi <ziyao@xxxxxxxxxxx> writes:
> Commit 58ff537109ac ("riscv: Omit optimized string routines when
> using KASAN") introduced calls to EXPORT_SYMBOL() in assembly string
> routines, which result in R_RISCV_64 relocations against
> .export_symbol section. As these rountines are reused by RISC-V
> purgatory and our relocator doesn't recognize these relocations, this
> fails kexec-file-load with dmesg like
>
> [ 11.344251] kexec_image: Unknown rela relocation: 2
> [ 11.345972] kexec_image: Error loading purgatory ret=-8
>
> Let's support R_RISCV_64 relocation to fix kexec on 64-bit RISC-V.
> 32-bit variant isn't covered since KEXEC_FILE and KEXEC_PURGATORY isn't
> available.
Hi!
This patch does fix the vmlinux loading for kexec-file -- very nice!
However, I haven't been able to get kexec to successfully boot a kernel
from qemu, i.e.:
kexec -s -l /path/to/vmlinux # fixed w/ your patch
kexec -e # hangs after "Bye..."
Same when I try vanilla kexec (kexec -c -l /path/to/vmlinux). kexec with
an Image works for me in qemu.
Before I start to bisect too much; What config/qemu did you use to test
this?
Thanks,
Björn