On Tue, 10 Mar 2020, Greg Kroah-Hartman wrote:
From: H.J. Lu <hjl.tools@xxxxxxxxx>
[ Upstream commit df6d4f9db79c1a5d6f48b59db35ccd1e9ff9adfc ]
GCC 10 changed the default to -fno-common, which leads to
LD arch/x86/boot/compressed/vmlinux
ld: arch/x86/boot/compressed/pgtable_64.o:(.bss+0x0): multiple definition of `__force_order'; \
arch/x86/boot/compressed/kaslr_64.o:(.bss+0x0): first defined here
make[2]: *** [arch/x86/boot/compressed/Makefile:119: arch/x86/boot/compressed/vmlinux] Error 1
Since __force_order is already provided in pgtable_64.c, there is no
need to declare __force_order in kaslr_64.c.
Signed-off-by: H.J. Lu <hjl.tools@xxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Link: https://lkml.kernel.org/r/20200124181811.4780-1-hjl.tools@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/x86/boot/compressed/pagetable.c | 3 ---
1 file changed, 3 deletions(-)
diff --git a/arch/x86/boot/compressed/pagetable.c b/arch/x86/boot/compressed/pagetable.c
index 56589d0a804b1..2591f8f6d45f2 100644
--- a/arch/x86/boot/compressed/pagetable.c
+++ b/arch/x86/boot/compressed/pagetable.c
@@ -25,9 +25,6 @@
#define __PAGE_OFFSET __PAGE_OFFSET_BASE
#include "../../mm/ident_map.c"
-/* Used by pgtable.h asm code to force instruction serialization. */
-unsigned long __force_order;
-
/* Used to track our page table allocation area. */
struct alloc_pgt_data {
unsigned char *pgt_buf;
This ends up for me in:
arch/x86/boot/compressed/pagetable.o: In function
`initialize_identity_maps':
pagetable.c:(.text+0x309): undefined reference to `__force_order'
arch/x86/boot/compressed/pagetable.o: In function
`finalize_identity_maps':
pagetable.c:(.text+0x41a): undefined reference to `__force_order'
pgtable_64.c doesn't exist in v4.9 for x86.
So I guess it's not correct to remove __force_order from pagetable.c?
Thomas