[Qemu-devel] [PATCH uq/master v2 2/2] kvm: forward INIT signals coming from the chipset

[Paolo Bonzini]

When an INIT comes in, we can do the entire reset process in userspace.
However, we have to be careful and move APs into KVM_MP_STATE_INIT_RECEIVED,
so that the in-kernel APIC will listen to startup IPIs.

Signed-off-by: Paolo Bonzini <address@hidden>
---
 target-i386/helper.c   |  4 ++++
 target-i386/kvm.c      | 37 ++++++++++++++++++++++++++-----------
 target-i386/kvm_i386.h |  1 +
 3 files changed, 31 insertions(+), 11 deletions(-)

diff --git a/target-i386/helper.c b/target-i386/helper.c
index 9449a0c..bbc5adf 100644
--- a/target-i386/helper.c
+++ b/target-i386/helper.c
@@ -19,6 +19,7 @@
 
 #include "cpu.h"
 #include "sysemu/kvm.h"
+#include "kvm_i386.h"
 #ifndef CONFIG_USER_ONLY
 #include "sysemu/sysemu.h"
 #include "monitor/monitor.h"
@@ -1290,6 +1291,9 @@ void do_cpu_init(X86CPU *cpu)
     cpu_reset(cs);
     cs->interrupt_request = sipi;
     env->pat = pat;
+    if (kvm_enabled()) {
+        kvm_arch_do_init_vcpu(cs);
+    }
     apic_init_reset(env->apic_state);
 }
 
diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index df30fa6..42a4571 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -30,6 +30,8 @@
 #include "qemu/config-file.h"
 #include "hw/pc.h"
 #include "hw/apic.h"
+#include "hw/apic_internal.h"
+#include "hw/apic-msidef.h"
 #include "exec/ioport.h"
 #include "hyperv.h"
 #include "hw/pci/pci.h"
@@ -676,6 +678,17 @@ void kvm_arch_reset_vcpu(CPUState *cs)
     }
 }
 
+void kvm_arch_do_init_vcpu(CPUState *cs)
+{
+    X86CPU *cpu = X86_CPU(cs);
+    CPUX86State *env = &cpu->env;
+
+    /* APs go straight into wait-for-SIPI state after INIT# is asserted.  */
+    if (env->mp_state == KVM_MP_STATE_UNINITIALIZED) {
+        env->mp_state = KVM_MP_STATE_INIT_RECEIVED;
+    }
+}
+
 static int kvm_get_supported_msrs(KVMState *s)
 {
     static int kvm_supported_msrs;
@@ -1773,14 +1786,15 @@ void kvm_arch_pre_run(CPUState *cpu, struct kvm_run 
*run)
         }
     }
 
-    if (!kvm_irqchip_in_kernel()) {
-        /* Force the VCPU out of its inner loop to process any INIT requests
-         * or pending TPR access reports. */
-        if (cpu->interrupt_request &
-            (CPU_INTERRUPT_INIT | CPU_INTERRUPT_TPR)) {
-            cpu->exit_request = 1;
-        }
+    /* Force the VCPU out of its inner loop to process any INIT requests
+     * or (for userspace APIC, but it is cheap to combine the checks here)
+     * pending TPR access reports.
+     */
+    if (cpu->interrupt_request & (CPU_INTERRUPT_INIT | CPU_INTERRUPT_TPR)) {
+        cpu->exit_request = 1;
+    }
 
+    if (!kvm_irqchip_in_kernel()) {
         /* Try to inject an interrupt if the guest can accept it */
         if (run->ready_for_interrupt_injection &&
             (cpu->interrupt_request & CPU_INTERRUPT_HARD) &&
@@ -1860,6 +1874,11 @@ int kvm_arch_process_async_events(CPUState *cs)
         }
     }
 
+    if (cs->interrupt_request & CPU_INTERRUPT_INIT) {
+        kvm_cpu_synchronize_state(env);
+        do_cpu_init(cpu);
+    }
+
     if (kvm_irqchip_in_kernel()) {
         return 0;
     }
@@ -1873,10 +1892,6 @@ int kvm_arch_process_async_events(CPUState *cs)
         (cs->interrupt_request & CPU_INTERRUPT_NMI)) {
         cs->halted = 0;
     }
-    if (cs->interrupt_request & CPU_INTERRUPT_INIT) {
-        kvm_cpu_synchronize_state(env);
-        do_cpu_init(cpu);
-    }
     if (cs->interrupt_request & CPU_INTERRUPT_SIPI) {
         kvm_cpu_synchronize_state(env);
         do_cpu_sipi(cpu);
diff --git a/target-i386/kvm_i386.h b/target-i386/kvm_i386.h
index 3accc2d..ce38ee6 100644
--- a/target-i386/kvm_i386.h
+++ b/target-i386/kvm_i386.h
@@ -15,6 +15,7 @@
 
 bool kvm_allows_irq0_override(void);
 void kvm_arch_reset_vcpu(CPUState *cs);
+void kvm_arch_do_init_vcpu(CPUState *cs);
 
 int kvm_device_pci_assign(KVMState *s, PCIHostDeviceAddress *dev_addr,
                           uint32_t flags, uint32_t *dev_id);
-- 
1.8.1.4