From: Sami Tolvanen <samitolva...@google.com> [ Upstream commit 6a03469a1edc94da52b65478f1e00837add869a3 ]
With CONFIG_LD_DEAD_CODE_DATA_ELIMINATION=y, we compile the kernel with -fdata-sections, which also splits the .bss section. The new section, with a new .bss.* name, which pattern gets missed by the main x86 linker script which only expects the '.bss' name. This results in the discarding of the second part and a too small, truncated .bss section and an unhappy, non-working kernel. Use the common BSS_MAIN macro in the linker script to properly capture and merge all the generated BSS sections. Signed-off-by: Sami Tolvanen <samitolva...@google.com> Reviewed-by: Nick Desaulniers <ndesaulni...@google.com> Reviewed-by: Kees Cook <keesc...@chromium.org> Cc: Borislav Petkov <b...@alien8.de> Cc: Kees Cook <keesc...@chromium.org> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Nicholas Piggin <npig...@gmail.com> Cc: Nick Desaulniers <ndesaulni...@google.com> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Thomas Gleixner <t...@linutronix.de> Link: http://lkml.kernel.org/r/20190415164956.124067-1-samitolva...@google.com [ Extended the changelog. ] Signed-off-by: Ingo Molnar <mi...@kernel.org> Signed-off-by: Sasha Levin <sas...@kernel.org> --- arch/x86/kernel/vmlinux.lds.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S index ee3b5c7d662e..c45214c44e61 100644 --- a/arch/x86/kernel/vmlinux.lds.S +++ b/arch/x86/kernel/vmlinux.lds.S @@ -362,7 +362,7 @@ SECTIONS .bss : AT(ADDR(.bss) - LOAD_OFFSET) { __bss_start = .; *(.bss..page_aligned) - *(.bss) + *(BSS_MAIN) BSS_DECRYPTED . = ALIGN(PAGE_SIZE); __bss_stop = .; -- 2.20.1
