[PATCH 02/29] powerpc: Remove PT_NOTE workaround

From: Kees Cook
Date: Thu Sep 26 2019 - 13:56:19 EST


The kernel requires gcc 4.6 now, so this PT_NOTE workaround can be
removed in preparation for moving NOTES into RO_DATA.

Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
arch/powerpc/kernel/vmlinux.lds.S | 24 ++----------------------
1 file changed, 2 insertions(+), 22 deletions(-)

diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S
index 81e672654789..a3c8492b2b19 100644
--- a/arch/powerpc/kernel/vmlinux.lds.S
+++ b/arch/powerpc/kernel/vmlinux.lds.S
@@ -20,20 +20,6 @@ ENTRY(_stext)
PHDRS {
kernel PT_LOAD FLAGS(7); /* RWX */
note PT_NOTE FLAGS(0);
- dummy PT_NOTE FLAGS(0);
-
- /* binutils < 2.18 has a bug that makes it misbehave when taking an
- ELF file with all segments at load address 0 as input. This
- happens when running "strip" on vmlinux, because of the AT() magic
- in this linker script. People using GCC >= 4.2 won't run into
- this problem, because the "build-id" support will put some data
- into the "notes" segment (at a non-zero load address).
-
- To work around this, we force some data into both the "dummy"
- segment and the kernel segment, so the dummy segment will get a
- non-zero load address. It's not enough to always create the
- "notes" segment, since if nothing gets assigned to it, its load
- address will be zero. */
}

#ifdef CONFIG_PPC64
@@ -178,14 +164,8 @@ SECTIONS
EXCEPTION_TABLE(0)

NOTES :kernel :note
-
- /* The dummy segment contents for the bug workaround mentioned above
- near PHDRS. */
- .dummy : AT(ADDR(.dummy) - LOAD_OFFSET) {
- LONG(0)
- LONG(0)
- LONG(0)
- } :kernel :dummy
+ /* Restore program header away from PT_NOTE. */
+ .dummy : { *(.dummy) } :kernel

/*
* Init sections discarded at runtime
--
2.17.1