[PATCH AUTOSEL 6.6 19/40] LoongArch: Record pc instead of offset in la_abs relocation

Sasha Levin
2023-11-28T21:07:57Z

From: WANG Rui <wangrui@loongson.cn>

[ Upstream commit aa0cbc1b506b090c3a775b547c693ada108cc0d7 ]

To clarify, the previous version functioned flawlessly. However, it's
worth noting that the LLVM's LoongArch backend currently lacks support
for cross-section label calculations. With this patch, we enable the use
of clang to compile relocatable kernels.

Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: WANG Rui <wangrui@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/loongarch/include/asm/asmmacro.h | 3 +--
arch/loongarch/include/asm/setup.h | 2 +-
arch/loongarch/kernel/relocate.c | 2 +-
3 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/arch/loongarch/include/asm/asmmacro.h b/arch/loongarch/include/asm/asmmacro.h
index c9544f358c339..655db7d7a4279 100644
--- a/arch/loongarch/include/asm/asmmacro.h
+++ b/arch/loongarch/include/asm/asmmacro.h
@@ -609,8 +609,7 @@
lu32i.d \reg, 0
lu52i.d \reg, \reg, 0
.pushsection ".la_abs", "aw", %progbits
- 768:
- .dword 768b-766b
+ .dword 766b
.dword \sym
.popsection
#endif
diff --git a/arch/loongarch/include/asm/setup.h b/arch/loongarch/include/asm/setup.h
index a0bc159ce8bdc..ee52fb1e99631 100644
--- a/arch/loongarch/include/asm/setup.h
+++ b/arch/loongarch/include/asm/setup.h
@@ -25,7 +25,7 @@ extern void set_merr_handler(unsigned long offset, void *addr, unsigned long len
#ifdef CONFIG_RELOCATABLE

struct rela_la_abs {
- long offset;
+ long pc;
long symvalue;
};

diff --git a/arch/loongarch/kernel/relocate.c b/arch/loongarch/kernel/relocate.c
index 6c3eff9af9fb1..288b739ca88dd 100644
--- a/arch/loongarch/kernel/relocate.c
+++ b/arch/loongarch/kernel/relocate.c
@@ -52,7 +52,7 @@ static inline void __init relocate_absolute(long random_offset)
for (p = begin; (void *)p < end; p++) {
long v = p->symvalue;
uint32_t lu12iw, ori, lu32id, lu52id;
- union loongarch_instruction *insn = (void *)p - p->offset;
+ union loongarch_instruction *insn = (void *)p->pc;

lu12iw = (v >> 12) & 0xfffff;
ori = v & 0xfff;
--
2.42.0