MIPS: Loongson-3: Calculate ra properly when unwinding the stack
Loongson-3 has 16-bytes load/store instructions: gslq and gssq. This
patch calculate ra properly when unwinding the stack, if ra is saved
by gssq and restored by gslq.
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index b36297e..37f05c8 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -279,7 +279,21 @@ static inline int is_ra_save_ins(union mips_instruction *ip, int *poff)
*poff = ip->i_format.simmediate / sizeof(ulong);
return 1;
}
-
+#ifdef CONFIG_CPU_LOONGSON64
+ if ((ip->loongson3_lswc2_format.opcode == swc2_op) &&
+ (ip->loongson3_lswc2_format.ls == 1) &&
+ (ip->loongson3_lswc2_format.fr == 0) &&
+ (ip->loongson3_lswc2_format.base == 29)) {
+ if (ip->loongson3_lswc2_format.rt == 31) {
+ *poff = ip->loongson3_lswc2_format.offset << 1;
+ return 1;
+ }
+ if (ip->loongson3_lswc2_format.rq == 31) {
+ *poff = (ip->loongson3_lswc2_format.offset << 1) + 1;
+ return 1;
+ }
+ }
+#endif
return 0;
#endif
}