summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLeonid Yegoshin <Leonid.Yegoshin@imgtec.com>2016-08-25 10:37:38 -0700
committerSasha Levin <alexander.levin@verizon.com>2017-06-13 09:29:20 -0400
commit62494116045eac405cb83ab8a7c24c1c8b088892 (patch)
tree322733666c45b820601701d8f5486f679197f929
parent48ea252abd409832aa181edf8c3ae94d95c182f2 (diff)
MIPS: R2-on-R6 MULTU/MADDU/MSUBU emulation bugfix
[ Upstream commit d65e5677ad5b3a49c43f60ec07644dc1f87bbd2e ] 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. Fixes: b0a668fb2038 ("MIPS: kernel: mips-r2-to-r6-emul: Add R2 emulator for MIPS R6") Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> Reported-by: Nikola.Veljkovic@imgtec.com Cc: paul.burton@imgtec.com Cc: yamada.masahiro@socionext.com Cc: akpm@linux-foundation.org Cc: andrea.gelmini@gelma.net Cc: macro@imgtec.com Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/14043/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
-rw-r--r--arch/mips/kernel/mips-r2-to-r6-emul.c12
1 files 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 488e50dd2fe6..d477508450de 100644
--- a/arch/mips/kernel/mips-r2-to-r6-emul.c
+++ b/arch/mips/kernel/mips-r2-to-r6-emul.c
@@ -433,8 +433,8 @@ 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);
@@ -670,9 +670,9 @@ 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);
@@ -728,9 +728,9 @@ 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);