Merge tag 'for-upstream' of https://gitlab.com/bonzini/qemu into stagingHEADmaster

* target/alpha: Fix for record/replay issue
* accel/nitro: New Nitro Enclaves accelerator
* generic + kvm: add support for rebuilding VMs on reset
* audio requirements cleanup
* vmmouse: Fix hypercall clobbers
* rust: use checked_div to make clippy happy
* kvm: Don't clear pending #SMI in kvm_get_vcpu_events
* target/i386/emulate: rework MMU code, many fixes
* target/i386/whpx: replace winhvemulation with target/i386/emulate
* target/i386/whpx: x2apic support
* target/i386/whpx: vapic support
* kvm: support for the "ignore guest PAT" quirk
* target/i386: add ITS_NO bit for the arch-capabilities MSR
* target/i386: add MBEC bit for nested VMX

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* tag 'for-upstream' of https://gitlab.com/bonzini/qemu: (102 commits)
  target/i386: emulate: fix scas
  whpx: i386: expose HV_X64_MSR_APIC_FREQUENCY when kernel-irqchip=off
  whpx: i386: enable PMU
  target/i386: emulate: more 64-bit register handling
  whpx: i386: warn on unsupported MSR access instead of failing silently
  whpx: i386: enable synthetic processor features
  whpx: i386: enable all supported host features
  whpx: i386: move whpx_vcpu_kick_out_of_hlt() invocation to interrupt raise time
  target/i386: introduce ClearwaterForest-v3 to expose ITS_NO
  target/i386: introduce SierraForest-v5 to expose ITS_NO
  target/i386: introduce GraniteRapids-v5 to expose ITS_NO
  target/i386: introduce SapphireRapids-v6 to expose ITS_NO
  target/i386: Add MSR_IA32_ARCH_CAPABILITIES ITS_NO
  target/i386: Add VMX_SECONDARY_EXEC_MODE_BASED_EPT_EXEC
  Reapply "rcu: Unify force quiescent state"
  target/alpha: Reset CPU
  hw: i386: vapic: enable on WHPX with user-mode irqchip
  whpx: x86: kick out of HLT manually when using the kernel-irqchip
  whpx: x86: remove inaccurate comment
  KVM: i386: Default disable ignore guest PAT quirk
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

2 files changed, 68 insertions, 4 deletions

diff --git a/system/physmem.c b/system/physmem.c
index 2fb0c25..e5ff26a 100644
--- a/system/physmem.c
+++ b/system/physmem.c
@@ -2827,6 +2827,34 @@ found:
 }
 
 /*
+ * Creates new guest memfd for the ramblocks and closes the
+ * existing memfd.
+ */
+int ram_block_rebind(Error **errp)
+{
+    RAMBlock *block;
+
+    qemu_mutex_lock_ramlist();
+
+    RAMBLOCK_FOREACH(block) {
+        if (block->flags & RAM_GUEST_MEMFD) {
+            if (block->guest_memfd >= 0) {
+                close(block->guest_memfd);
+            }
+            block->guest_memfd = kvm_create_guest_memfd(block->max_length,
+                                                        0, errp);
+            if (block->guest_memfd < 0) {
+                qemu_mutex_unlock_ramlist();
+                return -1;
+            }
+
+        }
+    }
+    qemu_mutex_unlock_ramlist();
+    return 0;
+}
+
+/*
  * Finds the named RAMBlock
  *
  * name: The name of RAMBlock to find
diff --git a/system/runstate.c b/system/runstate.c
index d091a2b..eca722b 100644
--- a/system/runstate.c
+++ b/system/runstate.c
@@ -42,6 +42,7 @@
 #include "qapi/qapi-commands-run-state.h"
 #include "qapi/qapi-events-run-state.h"
 #include "qemu/accel.h"
+#include "accel/accel-ops.h"
 #include "qemu/error-report.h"
 #include "qemu/job.h"
 #include "qemu/log.h"
@@ -57,6 +58,7 @@
 #include "system/reset.h"
 #include "system/runstate.h"
 #include "system/runstate-action.h"
+#include "system/confidential-guest-support.h"
 #include "system/system.h"
 #include "system/tpm.h"
 #include "trace.h"
@@ -508,6 +510,9 @@ void qemu_system_reset(ShutdownCause reason)
 {
     MachineClass *mc;
     ResetType type;
+    AccelClass *ac = ACCEL_GET_CLASS(current_accel());
+    bool guest_state_rebuilt = false;
+    int ret;
 
     mc = current_machine ? MACHINE_GET_CLASS(current_machine) : NULL;
 
@@ -520,6 +525,29 @@ void qemu_system_reset(ShutdownCause reason)
     default:
         type = RESET_TYPE_COLD;
     }
+
+    if ((reason == SHUTDOWN_CAUSE_GUEST_RESET ||
+         reason == SHUTDOWN_CAUSE_HOST_QMP_SYSTEM_RESET) &&
+        (current_machine->new_accel_vmfd_on_reset || !cpus_are_resettable())) {
+        if (ac->rebuild_guest) {
+            ret = ac->rebuild_guest(current_machine);
+            if (ret < 0) {
+                error_report("unable to rebuild guest: %s(%d)",
+                             strerror(-ret), ret);
+                vm_stop(RUN_STATE_INTERNAL_ERROR);
+            } else {
+                info_report("virtual machine state has been rebuilt with new "
+                            "guest file handle.");
+                guest_state_rebuilt = true;
+            }
+        } else if (!cpus_are_resettable())  {
+            error_report("accelerator does not support reset!");
+        } else {
+            error_report("accelerator does not support rebuilding guest state,"
+                         " proceeding with normal reset!");
+        }
+    }
+
     if (mc && mc->reset) {
         mc->reset(current_machine, type);
     } else {
@@ -542,9 +570,16 @@ void qemu_system_reset(ShutdownCause reason)
      * it does _more_  than cpu_synchronize_all_post_reset().
      */
     if (cpus_are_resettable()) {
-        cpu_synchronize_all_post_reset();
-    } else {
-        assert(runstate_check(RUN_STATE_PRELAUNCH));
+        if (guest_state_rebuilt) {
+            /*
+             * If guest state has been rebuilt, then we
+             * need to sync full cpu state for non confidential guests post
+             * reset.
+             */
+            cpu_synchronize_all_post_init();
+        } else {
+            cpu_synchronize_all_post_reset();
+        }
     }
 
     vm_set_suspended(false);
@@ -697,7 +732,8 @@ void qemu_system_reset_request(ShutdownCause reason)
     if (reboot_action == REBOOT_ACTION_SHUTDOWN &&
         reason != SHUTDOWN_CAUSE_SUBSYSTEM_RESET) {
         shutdown_requested = reason;
-    } else if (!cpus_are_resettable()) {
+    } else if (!cpus_are_resettable() &&
+               !confidential_guest_can_rebuild_state(current_machine->cgs)) {
         error_report("cpus are not resettable, terminating");
         shutdown_requested = reason;
     } else {