From 9df69dcd143fe1e56083c456cc96eb92c367f336 Mon Sep 17 00:00:00 2001 From: David Gibson Date: Mon, 21 Nov 2016 16:28:12 +1100 Subject: [PATCH] target-ppc: Fix CPU migration from qemu-2.6 <-> later versions When migration for target-ppc was converted to vmstate, several VMSTATE_EQUAL() checks were foolishly included of things that really should be internal state. Specifically we verified equality of the insns_flags and insns_flags2 fields, which are used within TCG to determine which groups of instructions are available on this cpu model. Between qemu-2.6 and qemu-2.7 we made some changes to these classes which broke migration. This path fixes migration both forwards and backwards. On migration from 2.6 to later versions we import the fields into teporary variables, which we then ignore. In migration backwards, we populate the temporary fields from the runtime fields, but mask out the bits which were added after qemu-2.6, allowing the VMSTATE_EQUAL in qemu-2.6 to accept the stream. Signed-off-by: David Gibson Reviewed-by: Dr. David Alan Gilbert Reviewed-by: Thomas Huth Reviewed-by: Greg Kurz (cherry picked from commit 16a2497bd44cac1856e259654fd304079bd1dcdc) Signed-off-by: Michael Roth --- target-ppc/cpu.h | 6 ++++++ target-ppc/machine.c | 29 +++++++++++++++++++++++++---- 2 files changed, 31 insertions(+), 4 deletions(-) diff --git a/target-ppc/cpu.h b/target-ppc/cpu.h index 786ab5cdfa..d4d15095dd 100644 --- a/target-ppc/cpu.h +++ b/target-ppc/cpu.h @@ -1164,6 +1164,12 @@ struct PowerPCCPU { int cpu_dt_id; uint32_t max_compat; uint32_t cpu_version; + + /* fields used only during migration for compatibility hacks */ + target_ulong mig_msr_mask; + uint64_t mig_insns_flags; + uint64_t mig_insns_flags2; + uint32_t mig_nb_BATs; }; static inline PowerPCCPU *ppc_env_get_cpu(CPUPPCState *env) diff --git a/target-ppc/machine.c b/target-ppc/machine.c index 4820f22377..56a59e09b1 100644 --- a/target-ppc/machine.c +++ b/target-ppc/machine.c @@ -141,6 +141,21 @@ static void cpu_pre_save(void *opaque) PowerPCCPU *cpu = opaque; CPUPPCState *env = &cpu->env; int i; + uint64_t insns_compat_mask = + PPC_INSNS_BASE | PPC_ISEL | PPC_STRING | PPC_MFTB + | PPC_FLOAT | PPC_FLOAT_FSEL | PPC_FLOAT_FRES + | PPC_FLOAT_FSQRT | PPC_FLOAT_FRSQRTE | PPC_FLOAT_FRSQRTES + | PPC_FLOAT_STFIWX | PPC_FLOAT_EXT + | PPC_CACHE | PPC_CACHE_ICBI | PPC_CACHE_DCBZ + | PPC_MEM_SYNC | PPC_MEM_EIEIO | PPC_MEM_TLBIE | PPC_MEM_TLBSYNC + | PPC_64B | PPC_64BX | PPC_ALTIVEC + | PPC_SEGMENT_64B | PPC_SLBI | PPC_POPCNTB | PPC_POPCNTWD; + uint64_t insns_compat_mask2 = PPC2_VSX | PPC2_VSX207 | PPC2_DFP | PPC2_DBRX + | PPC2_PERM_ISA206 | PPC2_DIVE_ISA206 + | PPC2_ATOMIC_ISA206 | PPC2_FP_CVT_ISA206 + | PPC2_FP_TST_ISA206 | PPC2_BCTAR_ISA207 + | PPC2_LSQ_ISA207 | PPC2_ALTIVEC_207 + | PPC2_ISA205 | PPC2_ISA207S | PPC2_FP_CVT_S64 | PPC2_TM; env->spr[SPR_LR] = env->lr; env->spr[SPR_CTR] = env->ctr; @@ -162,6 +177,12 @@ static void cpu_pre_save(void *opaque) env->spr[SPR_IBAT4U + 2*i] = env->IBAT[0][i+4]; env->spr[SPR_IBAT4U + 2*i + 1] = env->IBAT[1][i+4]; } + + /* Hacks for migration compatibility between 2.6, 2.7 & 2.8 */ + cpu->mig_msr_mask = env->msr_mask; + cpu->mig_insns_flags = env->insns_flags & insns_compat_mask; + cpu->mig_insns_flags2 = env->insns_flags2 & insns_compat_mask2; + cpu->mig_nb_BATs = env->nb_BATs; } static int cpu_post_load(void *opaque, int version_id) @@ -562,10 +583,10 @@ const VMStateDescription vmstate_ppc_cpu = { /* FIXME: access_type? */ /* Sanity checking */ - VMSTATE_UINTTL_EQUAL(env.msr_mask, PowerPCCPU), - VMSTATE_UINT64_EQUAL(env.insns_flags, PowerPCCPU), - VMSTATE_UINT64_EQUAL(env.insns_flags2, PowerPCCPU), - VMSTATE_UINT32_EQUAL(env.nb_BATs, PowerPCCPU), + VMSTATE_UINTTL(mig_msr_mask, PowerPCCPU), + VMSTATE_UINT64(mig_insns_flags, PowerPCCPU), + VMSTATE_UINT64(mig_insns_flags2, PowerPCCPU), + VMSTATE_UINT32(mig_nb_BATs, PowerPCCPU), VMSTATE_END_OF_LIST() }, .subsections = (const VMStateDescription*[]) {