sparc64: Handle 32-bit tasks properly in compute_effective_address().

[ Upstream commit d037d16372bbe4d580342bebbb8826821ad9edf0 ]

If we have a 32-bit task we must chop off the top 32-bits of the
64-bit value just as the cpu would.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/sparc/kernel/unaligned_64.c b/arch/sparc/kernel/unaligned_64.c
index 8201c25e76697ad5f5a96de1b6921a3fb34372ac..4db8898199f7240d0ef01eddecc056e67ad369e6 100644 (file)
--- a/arch/sparc/kernel/unaligned_64.c
+++ b/arch/sparc/kernel/unaligned_64.c
@@ -163,17 +163,23 @@ static unsigned long *fetch_reg_addr(unsigned int reg, struct pt_regs *regs)
 unsigned long compute_effective_address(struct pt_regs *regs,
                                        unsigned int insn, unsigned int rd)
 {
+       int from_kernel = (regs->tstate & TSTATE_PRIV) != 0;
        unsigned int rs1 = (insn >> 14) & 0x1f;
        unsigned int rs2 = insn & 0x1f;
-       int from_kernel = (regs->tstate & TSTATE_PRIV) != 0;
+       unsigned long addr;
 
        if (insn & 0x2000) {
                maybe_flush_windows(rs1, 0, rd, from_kernel);
-               return (fetch_reg(rs1, regs) + sign_extend_imm13(insn));
+               addr = (fetch_reg(rs1, regs) + sign_extend_imm13(insn));
        } else {
                maybe_flush_windows(rs1, rs2, rd, from_kernel);
-               return (fetch_reg(rs1, regs) + fetch_reg(rs2, regs));
+               addr = (fetch_reg(rs1, regs) + fetch_reg(rs2, regs));
        }
+
+       if (!from_kernel && test_thread_flag(TIF_32BIT))
+               addr &= 0xffffffff;
+
+       return addr;
 }
 
 /* This is just to make gcc think die_if_kernel does return... */