[patch 06/14] firmware_loader: align .builtin_fw to 8
From: Andrew Morton <akpm@linux-foundation.org>
Date: 2021-02-09 21:42:10
Also in:
mm-commits
From: Fangrui Song <redacted> Subject: firmware_loader: align .builtin_fw to 8 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). Link: https://lkml.kernel.org/r/20201208054646.2913063-1-maskray@google.com Link: https://github.com/ClangBuiltLinux/linux/issues/1204 Fixes: 5658c76 ("firmware: allow firmware files to be built into kernel image") Signed-off-by: Fangrui Song <redacted> Reported-by: kernel test robot <redacted> Acked-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Douglas Anderson <dianders@chromium.org> Acked-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> --- include/asm-generic/vmlinux.lds.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/include/asm-generic/vmlinux.lds.h~firmware_loader-align-builtin_fw-to-8
+++ a/include/asm-generic/vmlinux.lds.h@@ -459,7 +459,7 @@ } \ \ /* Built-in firmware blobs */ \ - .builtin_fw : AT(ADDR(.builtin_fw) - LOAD_OFFSET) { \ + .builtin_fw : AT(ADDR(.builtin_fw) - LOAD_OFFSET) ALIGN(8) { \ __start_builtin_fw = .; \ KEEP(*(.builtin_fw)) \ __end_builtin_fw = .; \
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