Commit bc1c969f authored by Huacai Chen's avatar Huacai Chen Committed by Thomas Bogendoerfer
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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: default avatarHuacai Chen <chenhc@lemote.com>
Signed-off-by: default avatarThomas Bogendoerfer <tsbogend@alpha.franken.de>
parent 195615ec

arch/mips/kernel/process.c

+15 −1
Original line number Diff line number Diff line
@@ -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

}