On 16.05.14 16:27, Alexey Kardashevskiy wrote:
On 05/17/2014 12:18 AM, Alexander Graf wrote:
On 15.05.14 13:28, Alexey Kardashevskiy wrote:
The host kernel implements a KVM_REG_PPC_ARCH_COMPAT register which
this uses to enable a compatibility mode if any chosen.
Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru>
---
hw/ppc/spapr.c | 6 ++++++
hw/ppc/spapr_hcall.c | 4 ++++
target-ppc/kvm.c | 5 +++++
target-ppc/kvm_ppc.h | 6 ++++++
4 files changed, 21 insertions(+)
diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index a0882a1..f89be10 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -1376,6 +1376,12 @@ static void ppc_spapr_init(QEMUMachineInitArgs *args)
/* Tell KVM that we're in PAPR mode */
if (kvm_enabled()) {
kvmppc_set_papr(cpu);
+
+ if (cpu->max_compat &&
+ kvmppc_set_compat(cpu, cpu->max_compat) < 0) {
+ fprintf(stderr, "Unable to set compatibility mode\n");
+ exit(1);
Why is KVM special here?
Sorry, I am not following you here. There is no SPR for that which guest
kernel could change, this is a register from "kvm set/get one reg" interface.
So semantically, what is ppc_set_compat() then? Why would we have to set
the KVM SPR that represents which compat mode we're in here, but not the
TCG version of it?
+ }
}
if (cpu->max_compat) {
diff --git a/hw/ppc/spapr_hcall.c b/hw/ppc/spapr_hcall.c
index cb815c3..2ab21d3 100644
--- a/hw/ppc/spapr_hcall.c
+++ b/hw/ppc/spapr_hcall.c
@@ -834,6 +834,10 @@ static target_ulong
h_client_architecture_support(PowerPCCPU *cpu_,
CPU_FOREACH(cs) {
PowerPCCPU *cpu = POWERPC_CPU(cs);
+ if (kvmppc_set_compat(cpu, cpu_version) < 0) {
+ fprintf(stderr, "Unable to set compatibility mode\n");
+ return H_HARDWARE;
+ }
Just fold this into ppc_set_compat which will run from vcpu context.
TCG version cannot fail and KVM's one can. Adding non-void return value
would give impression that ppc_set_compat may fail while it cannot. Still fold?
Yes, please.
Alex