On Thu, Jan 07, 2021 at 01:20:55PM +0000, Alexander Lobakin wrote:
When building kernel with LD_DEAD_CODE_DATA_ELIMINATION, LLVM stack generates separate sections for compound literals, just like in case with enabled LTO [0]:
ld.lld: warning: drivers/built-in.a(mtd/nand/spi/gigadevice.o): (.data..compoundliteral.14) is being placed in '.data..compoundliteral.14' ld.lld: warning: drivers/built-in.a(mtd/nand/spi/gigadevice.o): (.data..compoundliteral.15) is being placed in '.data..compoundliteral.15' ld.lld: warning: drivers/built-in.a(mtd/nand/spi/gigadevice.o): (.data..compoundliteral.16) is being placed in '.data..compoundliteral.16' ld.lld: warning: drivers/built-in.a(mtd/nand/spi/gigadevice.o): (.data..compoundliteral.17) is being placed in '.data..compoundliteral.17'
[...]
Handle this by adding the related sections to generic definitions as suggested by Sami [0].
[0] https://lore.kernel.org/lkml/20201211184633.3213045-3-samitolvanen@google.co...
Suggested-by: Kees Cook keescook@chromium.org Signed-off-by: Alexander Lobakin alobakin@pm.me
Reviewed-by: Nathan Chancellor natechancellor@gmail.com
include/asm-generic/vmlinux.lds.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index b2b3d81b1535..5f2f5b1db84f 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -95,10 +95,10 @@ */ #ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION #define TEXT_MAIN .text .text.[0-9a-zA-Z_]* -#define DATA_MAIN .data .data.[0-9a-zA-Z_]* .data..LPBX* +#define DATA_MAIN .data .data.[0-9a-zA-Z_]* .data..L* .data..compoundliteral* #define SDATA_MAIN .sdata .sdata.[0-9a-zA-Z_]* -#define RODATA_MAIN .rodata .rodata.[0-9a-zA-Z_]* -#define BSS_MAIN .bss .bss.[0-9a-zA-Z_]* +#define RODATA_MAIN .rodata .rodata.[0-9a-zA-Z_]* .rodata..L* +#define BSS_MAIN .bss .bss.[0-9a-zA-Z_]* .bss..compoundliteral* #define SBSS_MAIN .sbss .sbss.[0-9a-zA-Z_]* #else
#define TEXT_MAIN .text
2.30.0