This is a note to let you know that I've just added the patch titled powerpc/sstep: Fix darn emulation to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: powerpc-sstep-fix-darn-emulation.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit c2423cdd0b8bbec3fb4ad55d734707328bfd863b Author: Sandipan Das <sandipan@xxxxxxxxxxxxx> Date: Thu Feb 4 13:37:44 2021 +0530 powerpc/sstep: Fix darn emulation [ 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> diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c index 0f228ee11ca4..a2e067f68dee 100644 --- a/arch/powerpc/lib/sstep.c +++ b/arch/powerpc/lib/sstep.c @@ -1853,7 +1853,7 @@ 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))