[PATCH 5.11 425/775] powerpc/sstep: Fix darn emulation

[Greg Kroah-Hartman]

From: Sandipan Das <sandipan@xxxxxxxxxxxxx>

[ Upstream commit 22b89ba178dd0a66a26699ead014a3e73ff8e044 ]

Commit 8813ff49607e ("powerpc/sstep: Check instruction validity
against ISA version before emulation") introduced a proper way to skip
unknown instructions. This makes sure that the same is used for the
darn instruction when the range selection bits have a reserved value.

Fixes: a23987ef267a ("powerpc: sstep: Add support for darn instruction")
Signed-off-by: Sandipan Das <sandipan@xxxxxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20210204080744.135785-2-sandipan@xxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 arch/powerpc/lib/sstep.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c
index 25cfa9c622c58..bb5c20d4ca91c 100644
--- a/arch/powerpc/lib/sstep.c
+++ b/arch/powerpc/lib/sstep.c
@@ -1918,7 +1918,7 @@ int analyse_instr(struct instruction_op *op, const struct pt_regs *regs,
 				goto compute_done;
 			}
 
-			return -1;
+			goto unknown_opcode;
 #ifdef __powerpc64__
 		case 777:	/* modsd */
 			if (!cpu_has_feature(CPU_FTR_ARCH_300))
-- 
2.27.0