KVM: PPC: Book3S: Allow only implemented hcalls to be enabled or disabled

This adds code to check that when the KVM_CAP_PPC_ENABLE_HCALL
capability is used to enable or disable in-kernel handling of an
hcall, that the hcall is actually implemented by the kernel.
If not an EINVAL error is returned.

This also checks the default-enabled list of hcalls and prints a
warning if any hcall there is not actually implemented.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>

diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 5c54d19..6955318 100644 (file)
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -3039,3 +3039,7 @@ not to attempt to handle the hcall, but will always exit to userspace
 to handle it.  Note that it may not make sense to enable some and
 disable others of a group of related hcalls, but KVM does not prevent
 userspace from doing that.
+
+If the hcall number specified is not one that has an in-kernel
+implementation, the KVM_ENABLE_CAP ioctl will fail with an EINVAL
+error.

diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h
index 052ab2a..ceb70aa 100644 (file)
--- a/arch/powerpc/include/asm/kvm_book3s.h
+++ b/arch/powerpc/include/asm/kvm_book3s.h
@@ -146,6 +146,7 @@ extern void kvmppc_mmu_invalidate_pte(struct kvm_vcpu *vcpu, struct hpte_cache *
 extern int kvmppc_mmu_hpte_sysinit(void);
 extern void kvmppc_mmu_hpte_sysexit(void);
 extern int kvmppc_mmu_hv_init(void);
+extern int kvmppc_book3s_hcall_implemented(struct kvm *kvm, unsigned long hc);
 
 extern int kvmppc_ld(struct kvm_vcpu *vcpu, ulong *eaddr, int size, void *ptr, bool data);
 extern int kvmppc_st(struct kvm_vcpu *vcpu, ulong *eaddr, int size, void *ptr, bool data);
@@ -188,6 +189,8 @@ extern u32 kvmppc_alignment_dsisr(struct kvm_vcpu *vcpu, unsigned int inst);
 extern ulong kvmppc_alignment_dar(struct kvm_vcpu *vcpu, unsigned int inst);
 extern int kvmppc_h_pr(struct kvm_vcpu *vcpu, unsigned long cmd);
 extern void kvmppc_pr_init_default_hcalls(struct kvm *kvm);
+extern int kvmppc_hcall_impl_pr(unsigned long cmd);
+extern int kvmppc_hcall_impl_hv_realmode(unsigned long cmd);
 extern void kvmppc_copy_to_svcpu(struct kvmppc_book3s_shadow_vcpu *svcpu,
                                 struct kvm_vcpu *vcpu);
 extern void kvmppc_copy_from_svcpu(struct kvm_vcpu *vcpu,

diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index 9c89cdd..e2fd5a1 100644 (file)
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -228,7 +228,7 @@ struct kvmppc_ops {
        void (*fast_vcpu_kick)(struct kvm_vcpu *vcpu);
        long (*arch_vm_ioctl)(struct file *filp, unsigned int ioctl,
                              unsigned long arg);
-
+       int (*hcall_implemented)(unsigned long hcall);
 };
 
 extern struct kvmppc_ops *kvmppc_hv_ops;

diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
index 90aa5c7..bd75902 100644 (file)
--- a/arch/powerpc/kvm/book3s.c
+++ b/arch/powerpc/kvm/book3s.c
@@ -925,6 +925,11 @@ int kvmppc_core_check_processor_compat(void)
        return 0;
 }
 
+int kvmppc_book3s_hcall_implemented(struct kvm *kvm, unsigned long hcall)
+{
+       return kvm->arch.kvm_ops->hcall_implemented(hcall);
+}
+
 static int kvmppc_book3s_init(void)
 {
        int r;

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index cf445d2..c4377c7 100644 (file)
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -645,6 +645,28 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
        return RESUME_GUEST;
 }
 
+static int kvmppc_hcall_impl_hv(unsigned long cmd)
+{
+       switch (cmd) {
+       case H_CEDE:
+       case H_PROD:
+       case H_CONFER:
+       case H_REGISTER_VPA:
+#ifdef CONFIG_KVM_XICS
+       case H_XIRR:
+       case H_CPPR:
+       case H_EOI:
+       case H_IPI:
+       case H_IPOLL:
+       case H_XIRR_X:
+#endif
+               return 1;
+       }
+
+       /* See if it's in the real-mode table */
+       return kvmppc_hcall_impl_hv_realmode(cmd);
+}
+
 static int kvmppc_handle_exit_hv(struct kvm_run *run, struct kvm_vcpu *vcpu,
                                 struct task_struct *tsk)
 {
@@ -2451,9 +2473,13 @@ static unsigned int default_hcall_list[] = {
 static void init_default_hcalls(void)
 {
        int i;
+       unsigned int hcall;
 
-       for (i = 0; default_hcall_list[i]; ++i)
-               __set_bit(default_hcall_list[i] / 4, default_enabled_hcalls);
+       for (i = 0; default_hcall_list[i]; ++i) {
+               hcall = default_hcall_list[i];
+               WARN_ON(!kvmppc_hcall_impl_hv(hcall));
+               __set_bit(hcall / 4, default_enabled_hcalls);
+       }
 }
 
 static struct kvmppc_ops kvm_ops_hv = {
@@ -2488,6 +2514,7 @@ static struct kvmppc_ops kvm_ops_hv = {
        .emulate_mfspr = kvmppc_core_emulate_mfspr_hv,
        .fast_vcpu_kick = kvmppc_fast_vcpu_kick_hv,
        .arch_vm_ioctl  = kvm_arch_vm_ioctl_hv,
+       .hcall_implemented = kvmppc_hcall_impl_hv,
 };
 
 static int kvmppc_book3s_init_hv(void)

diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c
index 7cde8a6..3b41447 100644 (file)
--- a/arch/powerpc/kvm/book3s_hv_builtin.c
+++ b/arch/powerpc/kvm/book3s_hv_builtin.c
@@ -212,3 +212,16 @@ bool kvm_hv_mode_active(void)
 {
        return atomic_read(&hv_vm_count) != 0;
 }
+
+extern int hcall_real_table[], hcall_real_table_end[];
+
+int kvmppc_hcall_impl_hv_realmode(unsigned long cmd)
+{
+       cmd /= 4;
+       if (cmd < hcall_real_table_end - hcall_real_table &&
+           hcall_real_table[cmd])
+               return 1;
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(kvmppc_hcall_impl_hv_realmode);

diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 33aaade..e66c1e3 100644 (file)
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -2042,6 +2042,7 @@ hcall_real_table:
        .long   0               /* 0x12c */
        .long   0               /* 0x130 */
        .long   DOTSYM(kvmppc_h_set_xdabr) - hcall_real_table
+       .globl  hcall_real_table_end
 hcall_real_table_end:
 
 ignore_hdec:

diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c
index 123ac7d..15fd6c2 100644 (file)
--- a/arch/powerpc/kvm/book3s_pr.c
+++ b/arch/powerpc/kvm/book3s_pr.c
@@ -1670,6 +1670,9 @@ static struct kvmppc_ops kvm_ops_pr = {
        .emulate_mfspr = kvmppc_core_emulate_mfspr_pr,
        .fast_vcpu_kick = kvm_vcpu_kick,
        .arch_vm_ioctl  = kvm_arch_vm_ioctl_pr,
+#ifdef CONFIG_PPC_BOOK3S_64
+       .hcall_implemented = kvmppc_hcall_impl_pr,
+#endif
 };
 
 

diff --git a/arch/powerpc/kvm/book3s_pr_papr.c b/arch/powerpc/kvm/book3s_pr_papr.c
index eacaa6e..6d0143f 100644 (file)
--- a/arch/powerpc/kvm/book3s_pr_papr.c
+++ b/arch/powerpc/kvm/book3s_pr_papr.c
@@ -309,6 +309,27 @@ int kvmppc_h_pr(struct kvm_vcpu *vcpu, unsigned long cmd)
        return EMULATE_FAIL;
 }
 
+int kvmppc_hcall_impl_pr(unsigned long cmd)
+{
+       switch (cmd) {
+       case H_ENTER:
+       case H_REMOVE:
+       case H_PROTECT:
+       case H_BULK_REMOVE:
+       case H_PUT_TCE:
+       case H_CEDE:
+#ifdef CONFIG_KVM_XICS
+       case H_XIRR:
+       case H_CPPR:
+       case H_EOI:
+       case H_IPI:
+       case H_IPOLL:
+       case H_XIRR_X:
+#endif
+               return 1;
+       }
+       return 0;
+}
 
 /*
  * List of hcall numbers to enable by default.
@@ -337,7 +358,11 @@ static unsigned int default_hcall_list[] = {
 void kvmppc_pr_init_default_hcalls(struct kvm *kvm)
 {
        int i;
+       unsigned int hcall;
 
-       for (i = 0; default_hcall_list[i]; ++i)
-               __set_bit(default_hcall_list[i] / 4, kvm->arch.enabled_hcalls);
+       for (i = 0; default_hcall_list[i]; ++i) {
+               hcall = default_hcall_list[i];
+               WARN_ON(!kvmppc_hcall_impl_pr(hcall));
+               __set_bit(hcall / 4, kvm->arch.enabled_hcalls);
+       }
 }

diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 3222a4d..7efc2b7 100644 (file)
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -1119,6 +1119,8 @@ static int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
                if (hcall > MAX_HCALL_OPCODE || (hcall & 3) ||
                    cap->args[1] > 1)
                        break;
+               if (!kvmppc_book3s_hcall_implemented(kvm, hcall))
+                       break;
                if (cap->args[1])
                        set_bit(hcall / 4, kvm->arch.enabled_hcalls);
                else