s390: wire up nmi command to raise a RESTART interrupt on S390

There is the 'nmi' command that is used to trigger a guest dump via kdump feature on x86.
s390 uses RESTART interrupt to trigger kdump.
So, this patch provides a mean to use 'nmi' command on s390 to raise RESTART interrupt.

The CPU to receive the RESTART interrupt is the "default" one.

There is an infrastructure to select the "default" CPU using 'cpu' command.
The 'info cpus' command can be used to see which one is the "default".

In order to wire up the RESTART to 'nmi' command we had to:
1. implement the kvm_s390_cpu_restart function by exporting the existing code
2. implement s390_cpu_restart function as kvm-aware wrapper
3. modify the qmp_inject_nmi function to enable (for s390) the scan for
   "default" CPU and call s390_cpu_restart for it;
3. fix some messages.

Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Alexander Graf <agraf@suse.de>

diff --git a/cpus.c b/cpus.c
index b9e5685e160755e110fcab98286e000f7ad7368b..d74cc117b38b947961db8ea5611de09230621d54 100644 (file)
--- a/cpus.c
+++ b/cpus.c
@@ -1401,6 +1401,20 @@ void qmp_inject_nmi(Error **errp)
             apic_deliver_nmi(env->apic_state);
         }
     }
+#elif defined(TARGET_S390X)
+    CPUState *cs;
+    S390CPU *cpu;
+
+    for (cs = first_cpu; cs != NULL; cs = cs->next_cpu) {
+        cpu = S390_CPU(cs);
+        if (cpu->env.cpu_num == monitor_get_cpu_index()) {
+            if (s390_cpu_restart(S390_CPU(cs)) == -1) {
+                error_set(errp, QERR_UNSUPPORTED);
+                return;
+            }
+            break;
+        }
+    }
 #else
     error_set(errp, QERR_UNSUPPORTED);
 #endif

diff --git a/hmp-commands.hx b/hmp-commands.hx
index 8c6b91a9c70ce8ff5ef5421b1e7e7eed7da6665a..628807f68454e0d7ea1bac427de235cedfb517a8 100644 (file)
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -822,7 +822,7 @@ The values that can be specified here depend on the machine type, but are
 the same that can be specified in the @code{-boot} command line option.
 ETEXI
 
-#if defined(TARGET_I386)
+#if defined(TARGET_I386) || defined(TARGET_S390X)
     {
         .name       = "nmi",
         .args_type  = "",
@@ -834,7 +834,7 @@ ETEXI
 STEXI
 @item nmi @var{cpu}
 @findex nmi
-Inject an NMI on the given CPU (x86 only).
+Inject an NMI (x86) or RESTART (s390x) on the given CPU.
 
 ETEXI
 

diff --git a/qmp-commands.hx b/qmp-commands.hx
index cf47e3fe72f183f5dbe843be9f7210e907a62a7e..bb09e72712d90cd3825fa52016beff96fe69c3da 100644 (file)
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -487,7 +487,7 @@ Example:
 <- { "return": {} }
 
 Note: inject-nmi fails when the guest doesn't support injecting.
-      Currently, only x86 guests do.
+      Currently, only x86 (NMI) and s390x (RESTART) guests do.
 
 EQMP
 

diff --git a/target-s390x/cpu.h b/target-s390x/cpu.h
index b866ea189db0f0729a6324d0828aa85876651c77..8be56488061ed66369113d84d1c21d0b361a05f3 100644 (file)
--- a/target-s390x/cpu.h
+++ b/target-s390x/cpu.h
@@ -1069,6 +1069,7 @@ void kvm_s390_enable_css_support(S390CPU *cpu);
 int kvm_s390_get_registers_partial(CPUState *cpu);
 int kvm_s390_assign_subch_ioeventfd(EventNotifier *notifier, uint32_t sch,
                                     int vq, bool assign);
+int kvm_s390_cpu_restart(S390CPU *cpu);
 #else
 static inline void kvm_s390_io_interrupt(S390CPU *cpu,
                                         uint16_t subchannel_id,
@@ -1093,8 +1094,20 @@ static inline int kvm_s390_assign_subch_ioeventfd(EventNotifier *notifier,
 {
     return -ENOSYS;
 }
+static inline int kvm_s390_cpu_restart(S390CPU *cpu)
+{
+    return -ENOSYS;
+}
 #endif
 
+static inline int s390_cpu_restart(S390CPU *cpu)
+{
+    if (kvm_enabled()) {
+        return kvm_s390_cpu_restart(cpu);
+    }
+    return -ENOSYS;
+}
+
 static inline void s390_io_interrupt(S390CPU *cpu,
                                      uint16_t subchannel_id,
                                      uint16_t subchannel_nr,

diff --git a/target-s390x/kvm.c b/target-s390x/kvm.c
index c7fcdfa8827f90fecf1707cc2a52837b625299e2..185c8f5a457cf5bb9297a94007d595346dda97f9 100644 (file)
--- a/target-s390x/kvm.c
+++ b/target-s390x/kvm.c
@@ -612,12 +612,12 @@ static int handle_diag(S390CPU *cpu, struct kvm_run *run, int ipb_code)
     return r;
 }
 
-static int s390_cpu_restart(S390CPU *cpu)
+int kvm_s390_cpu_restart(S390CPU *cpu)
 {
     kvm_s390_interrupt(cpu, KVM_S390_RESTART, 0);
     s390_add_running_cpu(cpu);
     qemu_cpu_kick(CPU(cpu));
-    DPRINTF("DONE: SIGP cpu restart: %p\n", &cpu->env);
+    DPRINTF("DONE: KVM cpu restart: %p\n", &cpu->env);
     return 0;
 }
 
@@ -686,7 +686,7 @@ static int handle_sigp(S390CPU *cpu, struct kvm_run *run, uint8_t ipa1)
 
     switch (order_code) {
         case SIGP_RESTART:
-            r = s390_cpu_restart(target_cpu);
+            r = kvm_s390_cpu_restart(target_cpu);
             break;
         case SIGP_STORE_STATUS_ADDR:
             r = s390_store_status(target_env, parameter);