On Fri, 12 Jan 2024 10:51:16 PST (-0800), Ard Biesheuvel wrote:
Hi Jan, On Fri, 12 Jan 2024 at 19:37, Jan Kiszka <jan.kiszka@xxxxxxxxxxx> wrote:From: Jan Kiszka <jan.kiszka@xxxxxxxxxxx> The cflags for the RISC-V efistub were missing -mno-relax, thus were under the risk that the compiler could use GP-relative addressing. That happened for _edata with binutils-2.41 and kernel 6.1, causing the relocation to fail due to an invalid kernel_size in handle_kernel_image. It was not yet observed with newer versions, but that may just be luck. Signed-off-by: Jan Kiszka <jan.kiszka@xxxxxxxxxxx> --- Something like this should go to stable as well, but we will need rebased patches. drivers/firmware/efi/libstub/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile index 06964a3c130f..d561d7de46a9 100644 --- a/drivers/firmware/efi/libstub/Makefile +++ b/drivers/firmware/efi/libstub/Makefile @@ -28,7 +28,7 @@ cflags-$(CONFIG_ARM) += -DEFI_HAVE_STRLEN -DEFI_HAVE_STRNLEN \ -DEFI_HAVE_MEMCHR -DEFI_HAVE_STRRCHR \ -DEFI_HAVE_STRCMP -fno-builtin -fpic \ $(call cc-option,-mno-single-pic-base) -cflags-$(CONFIG_RISCV) += -fpic -DNO_ALTERNATIVE +cflags-$(CONFIG_RISCV) += -fpic -DNO_ALTERNATIVE -mno-relaxCan we detect the presence of these references (via the relocation type)? We already do something similar for ordinary absolute references too.
If there's no `__global_pointer$` symbol then the linker won't make GP-relative relaxations (because it doesn't know where GP is). We usually define that symbol in the linker script, but I'm not entierly sure how libstub gets its linker script...
cflags-$(CONFIG_LOONGARCH) += -fpie cflags-$(CONFIG_EFI_PARAMS_FROM_FDT) += -I$(srctree)/scripts/dtc/libfdt -- 2.35.3
