[PATCH v6 3/3] riscv: fix building compressed EFI image

Dmitry Antipov
2026-04-25T18:52:11Z

When building vmlinuz.efi with CONFIG_EFI_ZBOOT enabled,
'__lshrdi3()' is also needed to fix yet another link error:

riscv32-linux-gnu-ld: drivers/firmware/efi/libstub/lib-cmdline.stub.o: in function `__efistub_.L49':
__efistub_cmdline.c:(.init.text+0x202): undefined reference to `__efistub___lshrdi3'

And since riscv64 can have CONFIG_EFI_ZBOOT but doesn't need
these library routines, rely on CONFIG_32BIT to manage linking
of lib-ashldi3.o and lib-lshrdi3.o on riscv32 only.

Reported-by: Charlie Jenkins <thecharlesjenkins@gmail.com>
Closes: https://lore.kernel.org/linux-riscv/20260409050018.GA371560@inky.localdomain
Tested-by: Charlie Jenkins <thecharlesjenkins@gmail.com>
Suggested-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
---
v6: adjust to match recent upstream changes
v5: rely on CONFIG_32BIT rather than dedicated Kconfig symbol (Ard)
v4: use more meaningful CONFIG_EFI_ZBOOT_USE_LIBGCC and adjust tags (Andy)
v3: initial version to join the series
---
drivers/firmware/efi/libstub/Makefile | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
index 983a438e35f3..e1c11d02a5cb 100644
--- a/drivers/firmware/efi/libstub/Makefile
+++ b/drivers/firmware/efi/libstub/Makefile
@@ -95,7 +95,9 @@ CFLAGS_zboot-decompress-gzip.o += -I$(srctree)/lib/zlib_inflate
zboot-obj-$(CONFIG_KERNEL_ZSTD) := zboot-decompress-zstd.o lib-xxhash.o
CFLAGS_zboot-decompress-zstd.o += -I$(srctree)/lib/zstd

-zboot-obj-$(CONFIG_RISCV) += lib-clz_ctz.o lib-ashldi3.o
+zboot-obj-$(CONFIG_RISCV) += lib-clz_ctz.o
+zboot-riscv-obj-$(CONFIG_32BIT) += lib-ashldi3.o lib-lshrdi3.o
+zboot-obj-$(CONFIG_RISCV) += lib-clz_ctz.o $(zboot-riscv-obj-y)
zboot-obj-$(CONFIG_LOONGARCH) += lib-clz_ctz.o lib-ashldi3.o
lib-$(CONFIG_EFI_ZBOOT) += zboot.o $(zboot-obj-y)

--
2.53.0