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 <harshpb@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
master
Nicholas Piggin 2023-06-14 00:16:23 +10:00
parent 99ea316e2a
commit 678b6f1af7
1 changed files with 5 additions and 0 deletions

View File

@ -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);
}