MIPS instructions MULTU, MADDU and MSUBU emulation requires registers HI/LO to be converted to signed 32bits before 64bit sign extension on MIPS64. Bug was found on running MIPS32 R2 test application on MIPS64 R6 kernel. Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@xxxxxxxxxx> Reported-by: Nikola.Veljkovic@xxxxxxxxxx --- arch/mips/kernel/mips-r2-to-r6-emul.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/arch/mips/kernel/mips-r2-to-r6-emul.c b/arch/mips/kernel/mips-r2-to-r6-emul.c index c3372cac6db2..697f84385665 100644 --- a/arch/mips/kernel/mips-r2-to-r6-emul.c +++ b/arch/mips/kernel/mips-r2-to-r6-emul.c @@ -434,8 +434,8 @@ static int multu_func(struct pt_regs *regs, u32 ir) rs = regs->regs[MIPSInst_RS(ir)]; res = (u64)rt * (u64)rs; rt = res; - regs->lo = (s64)rt; - regs->hi = (s64)(res >> 32); + regs->lo = (s64)(s32)rt; + regs->hi = (s64)(s32)(res >> 32); MIPS_R2_STATS(muls); @@ -671,9 +671,9 @@ static int maddu_func(struct pt_regs *regs, u32 ir) res += ((((s64)rt) << 32) | (u32)rs); rt = res; - regs->lo = (s64)rt; + regs->lo = (s64)(s32)rt; rs = res >> 32; - regs->hi = (s64)rs; + regs->hi = (s64)(s32)rs; MIPS_R2_STATS(dsps); @@ -729,9 +729,9 @@ static int msubu_func(struct pt_regs *regs, u32 ir) res = ((((s64)rt) << 32) | (u32)rs) - res; rt = res; - regs->lo = (s64)rt; + regs->lo = (s64)(s32)rt; rs = res >> 32; - regs->hi = (s64)rs; + regs->hi = (s64)(s32)rs; MIPS_R2_STATS(dsps);
