KVM: PPC: Use PACA backed shadow vcpu

We're being horribly racy right now. All the entry and exit code hijacks
random fields from the PACA that could easily be used by different code in
case we get interrupted, for example by a #MC or even page fault.

After discussing this with Ben, we figured it's best to reserve some more
space in the PACA and just shove off some vcpu state to there.

That way we can drastically improve the readability of the code, make it
less racy and less complex.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 30 insertions, 3 deletions

diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index a6c2b63227b3..1501e77c980c 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -194,6 +194,32 @@ int main(void)
         DEFINE(PACA_KVM_IN_GUEST, offsetof(struct paca_struct, kvm_in_guest));
         DEFINE(PACA_KVM_SLB, offsetof(struct paca_struct, kvm_slb));
         DEFINE(PACA_KVM_SLB_MAX, offsetof(struct paca_struct, kvm_slb_max));
+        DEFINE(PACA_KVM_CR, offsetof(struct paca_struct, shadow_vcpu.cr));
+        DEFINE(PACA_KVM_XER, offsetof(struct paca_struct, shadow_vcpu.xer));
+        DEFINE(PACA_KVM_R0, offsetof(struct paca_struct, shadow_vcpu.gpr[0]));
+        DEFINE(PACA_KVM_R1, offsetof(struct paca_struct, shadow_vcpu.gpr[1]));
+        DEFINE(PACA_KVM_R2, offsetof(struct paca_struct, shadow_vcpu.gpr[2]));
+        DEFINE(PACA_KVM_R3, offsetof(struct paca_struct, shadow_vcpu.gpr[3]));
+        DEFINE(PACA_KVM_R4, offsetof(struct paca_struct, shadow_vcpu.gpr[4]));
+        DEFINE(PACA_KVM_R5, offsetof(struct paca_struct, shadow_vcpu.gpr[5]));
+        DEFINE(PACA_KVM_R6, offsetof(struct paca_struct, shadow_vcpu.gpr[6]));
+        DEFINE(PACA_KVM_R7, offsetof(struct paca_struct, shadow_vcpu.gpr[7]));
+        DEFINE(PACA_KVM_R8, offsetof(struct paca_struct, shadow_vcpu.gpr[8]));
+        DEFINE(PACA_KVM_R9, offsetof(struct paca_struct, shadow_vcpu.gpr[9]));
+        DEFINE(PACA_KVM_R10, offsetof(struct paca_struct, shadow_vcpu.gpr[10]));
+        DEFINE(PACA_KVM_R11, offsetof(struct paca_struct, shadow_vcpu.gpr[11]));
+        DEFINE(PACA_KVM_R12, offsetof(struct paca_struct, shadow_vcpu.gpr[12]));
+        DEFINE(PACA_KVM_R13, offsetof(struct paca_struct, shadow_vcpu.gpr[13]));
+        DEFINE(PACA_KVM_HOST_R1, offsetof(struct paca_struct, shadow_vcpu.host_r1));
+        DEFINE(PACA_KVM_HOST_R2, offsetof(struct paca_struct, shadow_vcpu.host_r2));
+        DEFINE(PACA_KVM_VMHANDLER, offsetof(struct paca_struct,
+                                            shadow_vcpu.vmhandler));
+        DEFINE(PACA_KVM_RMHANDLER, offsetof(struct paca_struct,
+                                            shadow_vcpu.rmhandler));
+        DEFINE(PACA_KVM_SCRATCH0, offsetof(struct paca_struct,
+                                           shadow_vcpu.scratch0));
+        DEFINE(PACA_KVM_SCRATCH1, offsetof(struct paca_struct,
+                                           shadow_vcpu.scratch1));
 #endif
 #endif /* CONFIG_PPC64 */
 
@@ -389,8 +415,6 @@ int main(void)
         DEFINE(VCPU_HOST_PID, offsetof(struct kvm_vcpu, arch.host_pid));
         DEFINE(VCPU_GPRS, offsetof(struct kvm_vcpu, arch.gpr));
         DEFINE(VCPU_LR, offsetof(struct kvm_vcpu, arch.lr));
-        DEFINE(VCPU_CR, offsetof(struct kvm_vcpu, arch.cr));
-        DEFINE(VCPU_XER, offsetof(struct kvm_vcpu, arch.xer));
         DEFINE(VCPU_CTR, offsetof(struct kvm_vcpu, arch.ctr));
         DEFINE(VCPU_PC, offsetof(struct kvm_vcpu, arch.pc));
         DEFINE(VCPU_MSR, offsetof(struct kvm_vcpu, arch.msr));
@@ -415,7 +439,10 @@ int main(void)
         DEFINE(VCPU_TRAMPOLINE_ENTER, offsetof(struct kvm_vcpu, arch.trampoline_enter));
         DEFINE(VCPU_HIGHMEM_HANDLER, offsetof(struct kvm_vcpu, arch.highmem_handler));
         DEFINE(VCPU_HFLAGS, offsetof(struct kvm_vcpu, arch.hflags));
-#endif
+#else
+        DEFINE(VCPU_CR, offsetof(struct kvm_vcpu, arch.cr));
+        DEFINE(VCPU_XER, offsetof(struct kvm_vcpu, arch.xer));
+#endif /* CONFIG_PPC64 */
 #endif
 #ifdef CONFIG_44x
         DEFINE(PGD_T_LOG2, PGD_T_LOG2);