On Tue, Jan 5, 2021 at 9:45 AM Doug Anderson [off-list ref] wrote:

Hi,

On Mon, Dec 7, 2020 at 9:49 PM Fangrui Song [off-list ref] wrote:

quoted

arm64 references the start address of .builtin_fw (__start_builtin_fw)
with a pair of R_AARCH64_ADR_PREL_PG_HI21/R_AARCH64_LDST64_ABS_LO12_NC
relocations. The compiler is allowed to emit the
R_AARCH64_LDST64_ABS_LO12_NC relocation because struct builtin_fw in
include/linux/firmware.h is 8-byte aligned.

The R_AARCH64_LDST64_ABS_LO12_NC relocation requires the address to be a
multiple of 8, which may not be the case if .builtin_fw is empty.
Unconditionally align .builtin_fw to fix the linker error. 32-bit
architectures could use ALIGN(4) but that would add unnecessary
complexity, so just use ALIGN(8).

Fixes: 5658c76 ("firmware: allow firmware files to be built into kernel image")
Link: https://github.com/ClangBuiltLinux/linux/issues/1204
Reported-by: kernel test robot <redacted>
Signed-off-by: Fangrui Song <redacted>
Acked-by: Arnd Bergmann <arnd@arndb.de>

---
Change in v2:
* Use output section alignment instead of inappropriate ALIGN_FUNCTION()
---
 include/asm-generic/vmlinux.lds.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Tested-by: Douglas Anderson <dianders@chromium.org>

For whatever reason this is hitting developers on Chrome OS a whole
lot suddenly.  Any chance it could be landed?  Which tree should it go
through?

Andrew,
Would you mind picking up this patch for us, please?
https://lore.kernel.org/lkml/20201208054646.2913063-1-maskray@google.com/ (local)

-- 
Thanks,
~Nick Desaulniers