diff options
| author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2016-06-03 14:11:18 +0200 |
|---|---|---|
| committer | David Gibson <david@gibson.dropbear.id.au> | 2016-06-07 10:17:45 +1000 |
| commit | 1c953ba57ada0a8694abb5db4bc618dde35a4618 (patch) | |
| tree | 533b3dc2aa7d2db59a205a989b907f34e303d53a | |
| parent | 932ccbdd48cea5b86f895bdc7d6b409d24aa81cd (diff) | |
ppc: Fix hreg_store_msr() so that non-HV mode cannot alter MSR:HV
This helper is only used by the various instructions that can alter
MSR and not interrupts. Add a comment to that effect to the interrupt
code as well in case somebody wants to change this
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
| -rw-r--r-- | target-ppc/excp_helper.c | 8 | ||||
| -rw-r--r-- | target-ppc/helper_regs.h | 4 |
2 files changed, 8 insertions, 4 deletions
diff --git a/target-ppc/excp_helper.c b/target-ppc/excp_helper.c index a37009eb25..30e960e30b 100644 --- a/target-ppc/excp_helper.c +++ b/target-ppc/excp_helper.c @@ -709,8 +709,12 @@ static inline void powerpc_excp(PowerPCCPU *cpu, int excp_model, int excp) } } #endif - /* XXX: we don't use hreg_store_msr here as already have treated - * any special case that could occur. Just store MSR and update hflags + /* We don't use hreg_store_msr here as already have treated + * any special case that could occur. Just store MSR and update hflags + * + * Note: We *MUST* not use hreg_store_msr() as-is anyway because it + * will prevent setting of the HV bit which some exceptions might need + * to do. */ env->msr = new_msr & env->msr_mask; hreg_compute_hflags(env); diff --git a/target-ppc/helper_regs.h b/target-ppc/helper_regs.h index 57da931e3c..12af61cbf1 100644 --- a/target-ppc/helper_regs.h +++ b/target-ppc/helper_regs.h @@ -114,8 +114,8 @@ static inline int hreg_store_msr(CPUPPCState *env, target_ulong value, excp = 0; value &= env->msr_mask; #if !defined(CONFIG_USER_ONLY) - if (!alter_hv) { - /* mtmsr cannot alter the hypervisor state */ + /* Neither mtmsr nor guest state can alter HV */ + if (!alter_hv || !(env->msr & MSR_HVB)) { value &= ~MSR_HVB; value |= env->msr & MSR_HVB; } |