[PATCH] ARM: module: use sign_extend32() to extend the signedness

From: Masahiro Yamada
Date: Tue May 30 2023 - 14:03:36 EST


The function name clarifies the intention.

Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
---

KernelVersion: v6.4-rc1

arch/arm/kernel/module.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/arch/arm/kernel/module.c b/arch/arm/kernel/module.c
index d59c36dc0494..e74d84f58b77 100644
--- a/arch/arm/kernel/module.c
+++ b/arch/arm/kernel/module.c
@@ -169,8 +169,7 @@ apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,

offset = __mem_to_opcode_arm(*(u32 *)loc);
offset = (offset & 0x00ffffff) << 2;
- if (offset & 0x02000000)
- offset -= 0x04000000;
+ offset = sign_extend32(offset, 25);

offset += sym->st_value - loc;

@@ -236,7 +235,7 @@ apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
case R_ARM_MOVT_PREL:
offset = tmp = __mem_to_opcode_arm(*(u32 *)loc);
offset = ((offset & 0xf0000) >> 4) | (offset & 0xfff);
- offset = (offset ^ 0x8000) - 0x8000;
+ offset = sign_extend32(offset, 15);

offset += sym->st_value;
if (ELF32_R_TYPE(rel->r_info) == R_ARM_MOVT_PREL ||
@@ -344,8 +343,7 @@ apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
((~(j2 ^ sign) & 1) << 22) |
((upper & 0x03ff) << 12) |
((lower & 0x07ff) << 1);
- if (offset & 0x01000000)
- offset -= 0x02000000;
+ offset = sign_extend32(offset, 24);
offset += sym->st_value - loc;

/*
@@ -401,7 +399,7 @@ apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
offset = ((upper & 0x000f) << 12) |
((upper & 0x0400) << 1) |
((lower & 0x7000) >> 4) | (lower & 0x00ff);
- offset = (offset ^ 0x8000) - 0x8000;
+ offset = sign_extend32(offset, 15);
offset += sym->st_value;

if (ELF32_R_TYPE(rel->r_info) == R_ARM_THM_MOVT_PREL ||
--
2.39.2