From: WANG Xuerui <git@xxxxxxxxxx>
With recent trunk versions of binutils and gcc, alignment directives are
represented with R_LARCH_ALIGN relocs on LoongArch, which is necessary
for the linker to maintain alignment requirements during its relaxation
passes. And even though the kernel is built with relaxation disabled, so
far a small number of R_LARCH_RELAX marker relocs are still emitted as
part of la.* pseudo instructions in assembly. These two kinds of relocs
do not refer to symbols, which can trip up modpost's section mismatch
checks, because the r_offset of said relocs can be zero or any other
meaningless value, eventually leading to a `from == NULL` condition in
default_mismatch_handler and SIGSEGV.
As the two kinds of relocs are not concerned with symbols, just ignore
them for section mismatch check purposes.
Fixes: 3d36f4298ba9 ("LoongArch: Switch to relative exception tables")
Signed-off-by: WANG Xuerui <git@xxxxxxxxxx>
Cc: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Cc: Nathan Chancellor <nathan@xxxxxxxxxx>
Cc: Nicolas Schier <nicolas@xxxxxxxxx>
Cc: Youling Tang <tangyouling@xxxxxxxxxxx>
Cc: Huacai Chen <chenhuacai@xxxxxxxxxx>
Cc: loongarch@xxxxxxxxxxxxxxx
---
scripts/mod/modpost.c | 19 +++++++++++++++++--
1 file changed, 17 insertions(+), 2 deletions(-)
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index cb6406f485a9..a4df47372b95 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -1346,6 +1346,14 @@ static Elf_Addr addend_mips_rel(uint32_t *location, unsigned int r_type)
#define R_LARCH_SUB32 55
#endif
+#ifndef R_LARCH_RELAX
+#define R_LARCH_RELAX 100
+#endif
+
+#ifndef R_LARCH_ALIGN
+#define R_LARCH_ALIGN 102
+#endif
+
static void get_rel_type_and_sym(struct elf_info *elf, uint64_t r_info,
unsigned int *r_type, unsigned int *r_sym)
{
@@ -1400,9 +1408,16 @@ static void section_rela(struct module *mod, struct elf_info *elf,
continue;
break;
case EM_LOONGARCH:
- if (!strcmp("__ex_table", fromsec) &&
- r_type == R_LARCH_SUB32)
+ switch (r_type) {
+ case R_LARCH_SUB32:
+ if (!strcmp("__ex_table", fromsec))
+ continue;
+ break;
+ case R_LARCH_RELAX:
+ case R_LARCH_ALIGN:
+ /* these relocs do not refer to symbols */
continue;
+ }
break;
}
--
2.43.0
