From 678b6f1af75ef42f510495a81fe8562e872e9daf Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Wed, 14 Jun 2023 00:16:23 +1000 Subject: [PATCH] target/ppc: Prevent supervisor from modifying MSR[ME] Prevent guest state modifying the MSR[ME] bit. Per ISA: An attempt to modify MSR[ME] in privileged but non-hypervisor state is ignored (i.e., the bit is not changed). Reviewed-by: Harsh Prateek Bora Signed-off-by: Nicholas Piggin --- target/ppc/helper_regs.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/target/ppc/helper_regs.c b/target/ppc/helper_regs.c index 410b39c231..25258986e3 100644 --- a/target/ppc/helper_regs.c +++ b/target/ppc/helper_regs.c @@ -264,6 +264,11 @@ int hreg_store_msr(CPUPPCState *env, target_ulong value, int alter_hv) value &= ~MSR_HVB; value |= env->msr & MSR_HVB; } + /* Attempt to modify MSR[ME] in guest state is ignored */ + if (is_book3s_arch2x(env) && !(env->msr & MSR_HVB)) { + value &= ~(1 << MSR_ME); + value |= env->msr & (1 << MSR_ME); + } if ((value ^ env->msr) & (R_MSR_IR_MASK | R_MSR_DR_MASK)) { cpu_interrupt_exittb(cs); } -- 2.39.5