[Qemu-devel] [PATCH 0/6] [uq/master] More KVM upstream cleanups, fixes, enhancements

[Qemu-devel] [PATCH 0/6] [uq/master] More KVM upstream cleanups, fixes, enhancements

[Jan Kiszka]

Nothing critical, see patches for details.

Jan Kiszka (6):
  kvm: Fix coding style violations
  kvm: Drop return value of kvm_cpu_exec
  kvm: x86: Align kvm_arch_put_registers code with comment
  kvm: Stop on all fatal exit reasons
  kvm: Improve reporting of fatal errors
  kvm: x86: Prepare kvm_get_mp_state for in-kernel irqchip

 kvm-all.c           |  171 ++++++++++++++++++++++++++++-----------------------
 kvm-stub.c          |    4 +-
 kvm.h               |    2 +-
 target-i386/cpu.h   |    2 +
 target-i386/cpuid.c |    5 +-
 target-i386/kvm.c   |   46 +++++++++++++-
 target-ppc/kvm.c    |    4 +
 7 files changed, 148 insertions(+), 86 deletions(-)

[Qemu-devel] [PATCH 1/6] kvm: Fix coding style violations

[Jan Kiszka]

From: Jan Kiszka <jan.kiszka@siemens.com>

No functional changes.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---
 kvm-all.c |  137 ++++++++++++++++++++++++++++++++++--------------------------
 1 files changed, 78 insertions(+), 59 deletions(-)

diff --git a/kvm-all.c b/kvm-all.c
index 35fc73c..3bb5722 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -82,10 +82,12 @@ static KVMSlot *kvm_alloc_slot(KVMState *s)
 
     for (i = 0; i < ARRAY_SIZE(s->slots); i++) {
         /* KVM private memory slots */
-        if (i >= 8 && i < 12)
+        if (i >= 8 && i < 12) {
             continue;
-        if (s->slots[i].memory_size == 0)
+        }
+        if (s->slots[i].memory_size == 0) {
             return &s->slots[i];
+        }
     }
 
     fprintf(stderr, "%s: no free slot available\n", __func__);
@@ -220,9 +222,10 @@ int kvm_init_vcpu(CPUState *env)
     }
 
 #ifdef KVM_CAP_COALESCED_MMIO
-    if (s->coalesced_mmio && !s->coalesced_mmio_ring)
-        s->coalesced_mmio_ring = (void *) env->kvm_run +
-		s->coalesced_mmio * PAGE_SIZE;
+    if (s->coalesced_mmio && !s->coalesced_mmio_ring) {
+        s->coalesced_mmio_ring =
+            (void *)env->kvm_run + s->coalesced_mmio * PAGE_SIZE;
+    }
 #endif
 
     ret = kvm_arch_init_vcpu(env);
@@ -269,16 +272,14 @@ static int kvm_dirty_pages_log_change(target_phys_addr_t phys_addr,
 
 int kvm_log_start(target_phys_addr_t phys_addr, ram_addr_t size)
 {
-        return kvm_dirty_pages_log_change(phys_addr, size,
-                                          KVM_MEM_LOG_DIRTY_PAGES,
-                                          KVM_MEM_LOG_DIRTY_PAGES);
+    return kvm_dirty_pages_log_change(phys_addr, size, KVM_MEM_LOG_DIRTY_PAGES,
+                                      KVM_MEM_LOG_DIRTY_PAGES);
 }
 
 int kvm_log_stop(target_phys_addr_t phys_addr, ram_addr_t size)
 {
-        return kvm_dirty_pages_log_change(phys_addr, size,
-                                          0,
-                                          KVM_MEM_LOG_DIRTY_PAGES);
+    return kvm_dirty_pages_log_change(phys_addr, size, 0,
+                                      KVM_MEM_LOG_DIRTY_PAGES);
 }
 
 static int kvm_set_migration_log(int enable)
@@ -441,9 +442,8 @@ int kvm_check_extension(KVMState *s, unsigned int extension)
     return ret;
 }
 
-static void kvm_set_phys_mem(target_phys_addr_t start_addr,
-			     ram_addr_t size,
-			     ram_addr_t phys_offset)
+static void kvm_set_phys_mem(target_phys_addr_t start_addr, ram_addr_t size,
+                             ram_addr_t phys_offset)
 {
     KVMState *s = kvm_state;
     ram_addr_t flags = phys_offset & ~TARGET_PAGE_MASK;
@@ -550,13 +550,13 @@ static void kvm_set_phys_mem(target_phys_addr_t start_addr,
     }
 
     /* in case the KVM bug workaround already "consumed" the new slot */
-    if (!size)
+    if (!size) {
         return;
-
+    }
     /* KVM does not need to know about this memory */
-    if (flags >= IO_MEM_UNASSIGNED)
+    if (flags >= IO_MEM_UNASSIGNED) {
         return;
-
+    }
     mem = kvm_alloc_slot(s);
     mem->memory_size = size;
     mem->start_addr = start_addr;
@@ -572,30 +572,29 @@ static void kvm_set_phys_mem(target_phys_addr_t start_addr,
 }
 
 static void kvm_client_set_memory(struct CPUPhysMemoryClient *client,
-				  target_phys_addr_t start_addr,
-				  ram_addr_t size,
-				  ram_addr_t phys_offset)
+                                  target_phys_addr_t start_addr,
+                                  ram_addr_t size, ram_addr_t phys_offset)
 {
-	kvm_set_phys_mem(start_addr, size, phys_offset);
+    kvm_set_phys_mem(start_addr, size, phys_offset);
 }
 
 static int kvm_client_sync_dirty_bitmap(struct CPUPhysMemoryClient *client,
-					target_phys_addr_t start_addr,
-					target_phys_addr_t end_addr)
+                                        target_phys_addr_t start_addr,
+                                        target_phys_addr_t end_addr)
 {
-	return kvm_physical_sync_dirty_bitmap(start_addr, end_addr);
+    return kvm_physical_sync_dirty_bitmap(start_addr, end_addr);
 }
 
 static int kvm_client_migration_log(struct CPUPhysMemoryClient *client,
-				    int enable)
+                                    int enable)
 {
-	return kvm_set_migration_log(enable);
+    return kvm_set_migration_log(enable);
 }
 
 static CPUPhysMemoryClient kvm_cpu_phys_memory_client = {
-	.set_memory = kvm_client_set_memory,
-	.sync_dirty_bitmap = kvm_client_sync_dirty_bitmap,
-	.migration_log = kvm_client_migration_log,
+    .set_memory = kvm_client_set_memory,
+    .sync_dirty_bitmap = kvm_client_sync_dirty_bitmap,
+    .migration_log = kvm_client_migration_log,
 };
 
 int kvm_init(int smp_cpus)
@@ -612,9 +611,9 @@ int kvm_init(int smp_cpus)
 #ifdef KVM_CAP_SET_GUEST_DEBUG
     QTAILQ_INIT(&s->kvm_sw_breakpoints);
 #endif
-    for (i = 0; i < ARRAY_SIZE(s->slots); i++)
+    for (i = 0; i < ARRAY_SIZE(s->slots); i++) {
         s->slots[i].slot = i;
-
+    }
     s->vmfd = -1;
     s->fd = qemu_open("/dev/kvm", O_RDWR);
     if (s->fd == -1) {
@@ -625,8 +624,9 @@ int kvm_init(int smp_cpus)
 
     ret = kvm_ioctl(s, KVM_GET_API_VERSION, 0);
     if (ret < KVM_API_VERSION) {
-        if (ret > 0)
+        if (ret > 0) {
             ret = -EINVAL;
+        }
         fprintf(stderr, "kvm version too old\n");
         goto err;
     }
@@ -711,8 +711,9 @@ int kvm_init(int smp_cpus)
 #endif
 
     ret = kvm_arch_init(s, smp_cpus);
-    if (ret < 0)
+    if (ret < 0) {
         goto err;
+    }
 
     kvm_state = s;
     cpu_register_phys_memory_client(&kvm_cpu_phys_memory_client);
@@ -721,10 +722,12 @@ int kvm_init(int smp_cpus)
 
 err:
     if (s) {
-        if (s->vmfd != -1)
+        if (s->vmfd != -1) {
             close(s->vmfd);
-        if (s->fd != -1)
+        }
+        if (s->fd != -1) {
             close(s->fd);
+        }
     }
     qemu_free(s);
 
@@ -788,8 +791,9 @@ static void kvm_handle_internal_error(CPUState *env, struct kvm_run *run)
     cpu_dump_state(env, stderr, fprintf, 0);
     if (run->internal.suberror == KVM_INTERNAL_ERROR_EMULATION) {
         fprintf(stderr, "emulation failure\n");
-        if (!kvm_arch_stop_on_emulation_error(env))
-		return;
+        if (!kvm_arch_stop_on_emulation_error(env)) {
+            return;
+        }
     }
     /* FIXME: Should trigger a qmp message to let management know
      * something went wrong.
@@ -829,8 +833,9 @@ static void do_kvm_cpu_synchronize_state(void *_env)
 
 void kvm_cpu_synchronize_state(CPUState *env)
 {
-    if (!env->kvm_vcpu_dirty)
+    if (!env->kvm_vcpu_dirty) {
         run_on_cpu(env, do_kvm_cpu_synchronize_state, env);
+    }
 }
 
 void kvm_cpu_synchronize_post_reset(CPUState *env)
@@ -970,9 +975,9 @@ int kvm_ioctl(KVMState *s, int type, ...)
     va_end(ap);
 
     ret = ioctl(s->fd, type, arg);
-    if (ret == -1)
+    if (ret == -1) {
         ret = -errno;
-
+    }
     return ret;
 }
 
@@ -987,9 +992,9 @@ int kvm_vm_ioctl(KVMState *s, int type, ...)
     va_end(ap);
 
     ret = ioctl(s->vmfd, type, arg);
-    if (ret == -1)
+    if (ret == -1) {
         ret = -errno;
-
+    }
     return ret;
 }
 
@@ -1004,9 +1009,9 @@ int kvm_vcpu_ioctl(CPUState *env, int type, ...)
     va_end(ap);
 
     ret = ioctl(env->kvm_fd, type, arg);
-    if (ret == -1)
+    if (ret == -1) {
         ret = -errno;
-
+    }
     return ret;
 }
 
@@ -1067,8 +1072,9 @@ struct kvm_sw_breakpoint *kvm_find_sw_breakpoint(CPUState *env,
     struct kvm_sw_breakpoint *bp;
 
     QTAILQ_FOREACH(bp, &env->kvm_state->kvm_sw_breakpoints, entry) {
-        if (bp->pc == pc)
+        if (bp->pc == pc) {
             return bp;
+        }
     }
     return NULL;
 }
@@ -1123,8 +1129,9 @@ int kvm_insert_breakpoint(CPUState *current_env, target_ulong addr,
         }
 
         bp = qemu_malloc(sizeof(struct kvm_sw_breakpoint));
-        if (!bp)
+        if (!bp) {
             return -ENOMEM;
+        }
 
         bp->pc = addr;
         bp->use_count = 1;
@@ -1138,14 +1145,16 @@ int kvm_insert_breakpoint(CPUState *current_env, target_ulong addr,
                           bp, entry);
     } else {
         err = kvm_arch_insert_hw_breakpoint(addr, len, type);
-        if (err)
+        if (err) {
             return err;
+        }
     }
 
     for (env = first_cpu; env != NULL; env = env->next_cpu) {
         err = kvm_update_guest_debug(env, 0);
-        if (err)
+        if (err) {
             return err;
+        }
     }
     return 0;
 }
@@ -1159,8 +1168,9 @@ int kvm_remove_breakpoint(CPUState *current_env, target_ulong addr,
 
     if (type == GDB_BREAKPOINT_SW) {
         bp = kvm_find_sw_breakpoint(current_env, addr);
-        if (!bp)
+        if (!bp) {
             return -ENOENT;
+        }
 
         if (bp->use_count > 1) {
             bp->use_count--;
@@ -1168,21 +1178,24 @@ int kvm_remove_breakpoint(CPUState *current_env, target_ulong addr,
         }
 
         err = kvm_arch_remove_sw_breakpoint(current_env, bp);
-        if (err)
+        if (err) {
             return err;
+        }
 
         QTAILQ_REMOVE(&current_env->kvm_state->kvm_sw_breakpoints, bp, entry);
         qemu_free(bp);
     } else {
         err = kvm_arch_remove_hw_breakpoint(addr, len, type);
-        if (err)
+        if (err) {
             return err;
+        }
     }
 
     for (env = first_cpu; env != NULL; env = env->next_cpu) {
         err = kvm_update_guest_debug(env, 0);
-        if (err)
+        if (err) {
             return err;
+        }
     }
     return 0;
 }
@@ -1197,15 +1210,17 @@ void kvm_remove_all_breakpoints(CPUState *current_env)
         if (kvm_arch_remove_sw_breakpoint(current_env, bp) != 0) {
             /* Try harder to find a CPU that currently sees the breakpoint. */
             for (env = first_cpu; env != NULL; env = env->next_cpu) {
-                if (kvm_arch_remove_sw_breakpoint(env, bp) == 0)
+                if (kvm_arch_remove_sw_breakpoint(env, bp) == 0) {
                     break;
+                }
             }
         }
     }
     kvm_arch_remove_all_hw_breakpoints();
 
-    for (env = first_cpu; env != NULL; env = env->next_cpu)
+    for (env = first_cpu; env != NULL; env = env->next_cpu) {
         kvm_update_guest_debug(env, 0);
+    }
 }
 
 #else /* !KVM_CAP_SET_GUEST_DEBUG */
@@ -1237,8 +1252,9 @@ int kvm_set_signal_mask(CPUState *env, const sigset_t *sigset)
     struct kvm_signal_mask *sigmask;
     int r;
 
-    if (!sigset)
+    if (!sigset) {
         return kvm_vcpu_ioctl(env, KVM_SET_SIGNAL_MASK, NULL);
+    }
 
     sigmask = qemu_malloc(sizeof(*sigmask) + sizeof(*sigset));
 
@@ -1293,13 +1309,16 @@ int kvm_set_ioeventfd_pio_word(int fd, uint16_t addr, uint16_t val, bool assign)
         .fd = fd,
     };
     int r;
-    if (!kvm_enabled())
+    if (!kvm_enabled()) {
         return -ENOSYS;
-    if (!assign)
+    }
+    if (!assign) {
         kick.flags |= KVM_IOEVENTFD_FLAG_DEASSIGN;
+    }
     r = kvm_vm_ioctl(kvm_state, KVM_IOEVENTFD, &kick);
-    if (r < 0)
+    if (r < 0) {
         return r;
+    }
     return 0;
 #else
     return -ENOSYS;
-- 
1.7.1

[Qemu-devel] [PATCH 2/6] kvm: Drop return value of kvm_cpu_exec

[Jan Kiszka]

From: Jan Kiszka <jan.kiszka@siemens.com>

It is not used, it is not needed, so let's remove it.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---
 kvm-all.c  |    6 ++----
 kvm-stub.c |    4 ++--
 kvm.h      |    2 +-
 3 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/kvm-all.c b/kvm-all.c
index 3bb5722..858c252 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -850,7 +850,7 @@ void kvm_cpu_synchronize_post_init(CPUState *env)
     env->kvm_vcpu_dirty = 0;
 }
 
-int kvm_cpu_exec(CPUState *env)
+void kvm_cpu_exec(CPUState *env)
 {
     struct kvm_run *run = env->kvm_run;
     int ret;
@@ -943,7 +943,7 @@ int kvm_cpu_exec(CPUState *env)
 #ifdef KVM_CAP_SET_GUEST_DEBUG
             if (kvm_arch_debug(&run->debug.arch)) {
                 env->exception_index = EXCP_DEBUG;
-                return 0;
+                return;
             }
             /* re-enter, this exception was guest-internal */
             ret = 1;
@@ -960,8 +960,6 @@ int kvm_cpu_exec(CPUState *env)
         env->exit_request = 0;
         env->exception_index = EXCP_INTERRUPT;
     }
-
-    return ret;
 }
 
 int kvm_ioctl(KVMState *s, int type, ...)
diff --git a/kvm-stub.c b/kvm-stub.c
index 5384a4b..352c6a6 100644
--- a/kvm-stub.c
+++ b/kvm-stub.c
@@ -79,9 +79,9 @@ void kvm_cpu_synchronize_post_init(CPUState *env)
 {
 }
 
-int kvm_cpu_exec(CPUState *env)
+void kvm_cpu_exec(CPUState *env)
 {
-    abort ();
+    abort();
 }
 
 int kvm_has_sync_mmu(void)
diff --git a/kvm.h b/kvm.h
index 60a9b42..51ad56f 100644
--- a/kvm.h
+++ b/kvm.h
@@ -46,7 +46,7 @@ int kvm_has_xcrs(void);
 #ifdef NEED_CPU_H
 int kvm_init_vcpu(CPUState *env);
 
-int kvm_cpu_exec(CPUState *env);
+void kvm_cpu_exec(CPUState *env);
 
 #if !defined(CONFIG_USER_ONLY)
 int kvm_log_start(target_phys_addr_t phys_addr, ram_addr_t size);
-- 
1.7.1

[Qemu-devel] [PATCH 3/6] kvm: x86: Align kvm_arch_put_registers code with comment

[Jan Kiszka]

From: Jan Kiszka <jan.kiszka@siemens.com>

The ordering doesn't matter in this case, but better keep it consistent.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---
 target-i386/kvm.c |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index fda07d2..b4c6cd4 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -1388,12 +1388,12 @@ int kvm_arch_put_registers(CPUState *env, int level)
     if (ret < 0) {
         return ret;
     }
-    /* must be last */
-    ret = kvm_guest_debug_workarounds(env);
+    ret = kvm_put_debugregs(env);
     if (ret < 0) {
         return ret;
     }
-    ret = kvm_put_debugregs(env);
+    /* must be last */
+    ret = kvm_guest_debug_workarounds(env);
     if (ret < 0) {
         return ret;
     }
-- 
1.7.1

[Qemu-devel] [PATCH 4/6] kvm: Stop on all fatal exit reasons

[Jan Kiszka]

From: Jan Kiszka <jan.kiszka@siemens.com>

Ensure that we stop the guest whenever we face a fatal or unknown exit
reason. If we stop, we also have to enforce a cpu loop exit.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---
 kvm-all.c         |   15 +++++++++++----
 target-i386/kvm.c |    4 ++++
 target-ppc/kvm.c  |    4 ++++
 3 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/kvm-all.c b/kvm-all.c
index 858c252..1e258d9 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -774,7 +774,7 @@ static int kvm_handle_io(uint16_t port, void *data, int direction, int size,
 }
 
 #ifdef KVM_CAP_INTERNAL_ERROR_DATA
-static void kvm_handle_internal_error(CPUState *env, struct kvm_run *run)
+static int kvm_handle_internal_error(CPUState *env, struct kvm_run *run)
 {
 
     if (kvm_check_extension(kvm_state, KVM_CAP_INTERNAL_ERROR_DATA)) {
@@ -792,13 +792,13 @@ static void kvm_handle_internal_error(CPUState *env, struct kvm_run *run)
     if (run->internal.suberror == KVM_INTERNAL_ERROR_EMULATION) {
         fprintf(stderr, "emulation failure\n");
         if (!kvm_arch_stop_on_emulation_error(env)) {
-            return;
+            return 0;
         }
     }
     /* FIXME: Should trigger a qmp message to let management know
      * something went wrong.
      */
-    vm_stop(0);
+    return -1;
 }
 #endif
 
@@ -926,16 +926,19 @@ void kvm_cpu_exec(CPUState *env)
             break;
         case KVM_EXIT_UNKNOWN:
             DPRINTF("kvm_exit_unknown\n");
+            ret = -1;
             break;
         case KVM_EXIT_FAIL_ENTRY:
             DPRINTF("kvm_exit_fail_entry\n");
+            ret = -1;
             break;
         case KVM_EXIT_EXCEPTION:
             DPRINTF("kvm_exit_exception\n");
+            ret = -1;
             break;
 #ifdef KVM_CAP_INTERNAL_ERROR_DATA
         case KVM_EXIT_INTERNAL_ERROR:
-            kvm_handle_internal_error(env, run);
+            ret = kvm_handle_internal_error(env, run);
             break;
 #endif
         case KVM_EXIT_DEBUG:
@@ -956,6 +959,10 @@ void kvm_cpu_exec(CPUState *env)
         }
     } while (ret > 0);
 
+    if (ret < 0) {
+        vm_stop(0);
+        env->exit_request = 1;
+    }
     if (env->exit_request) {
         env->exit_request = 0;
         env->exception_index = EXCP_INTERRUPT;
diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index b4c6cd4..ca4eb7a 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -1534,6 +1534,10 @@ int kvm_arch_handle_exit(CPUState *env, struct kvm_run *run)
         DPRINTF("handle_hlt\n");
         ret = kvm_handle_halt(env);
         break;
+    default:
+        fprintf(stderr, "KVM: unknown exit reason %d\n", run->exit_reason);
+        ret = -1;
+        break;
     }
 
     return ret;
diff --git a/target-ppc/kvm.c b/target-ppc/kvm.c
index 5caa07c..849b404 100644
--- a/target-ppc/kvm.c
+++ b/target-ppc/kvm.c
@@ -307,6 +307,10 @@ int kvm_arch_handle_exit(CPUState *env, struct kvm_run *run)
         dprintf("handle halt\n");
         ret = kvmppc_handle_halt(env);
         break;
+    default:
+        fprintf(stderr, "KVM: unknown exit reason %d\n", run->exit_reason);
+        ret = -1;
+        break;
     }
 
     return ret;
-- 
1.7.1

[Qemu-devel] [PATCH 5/6] kvm: Improve reporting of fatal errors

[Jan Kiszka]

From: Jan Kiszka <jan.kiszka@siemens.com>

Report KVM_EXIT_UNKNOWN, KVM_EXIT_FAIL_ENTRY, and KVM_EXIT_EXCEPTION
with more details to stderr. The latter two are so far x86-only, so move
them into the arch-specific handler. Integrate the Intel real mode
warning on KVM_EXIT_FAIL_ENTRY that qemu-kvm carries, but actually
restrict it to Intel CPUs.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---
 kvm-all.c           |   19 ++++++-------------
 target-i386/cpu.h   |    2 ++
 target-i386/cpuid.c |    5 ++---
 target-i386/kvm.c   |   33 +++++++++++++++++++++++++++++++++
 4 files changed, 43 insertions(+), 16 deletions(-)

diff --git a/kvm-all.c b/kvm-all.c
index 1e258d9..237c762 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -776,17 +776,17 @@ static int kvm_handle_io(uint16_t port, void *data, int direction, int size,
 #ifdef KVM_CAP_INTERNAL_ERROR_DATA
 static int kvm_handle_internal_error(CPUState *env, struct kvm_run *run)
 {
-
+    fprintf(stderr, "KVM internal error.");
     if (kvm_check_extension(kvm_state, KVM_CAP_INTERNAL_ERROR_DATA)) {
         int i;
 
-        fprintf(stderr, "KVM internal error. Suberror: %d\n",
-                run->internal.suberror);
-
+        fprintf(stderr, " Suberror: %d\n", run->internal.suberror);
         for (i = 0; i < run->internal.ndata; ++i) {
             fprintf(stderr, "extra data[%d]: %"PRIx64"\n",
                     i, (uint64_t)run->internal.data[i]);
         }
+    } else {
+        fprintf(stderr, "\n");
     }
     cpu_dump_state(env, stderr, fprintf, 0);
     if (run->internal.suberror == KVM_INTERNAL_ERROR_EMULATION) {
@@ -925,15 +925,8 @@ void kvm_cpu_exec(CPUState *env)
             ret = 1;
             break;
         case KVM_EXIT_UNKNOWN:
-            DPRINTF("kvm_exit_unknown\n");
-            ret = -1;
-            break;
-        case KVM_EXIT_FAIL_ENTRY:
-            DPRINTF("kvm_exit_fail_entry\n");
-            ret = -1;
-            break;
-        case KVM_EXIT_EXCEPTION:
-            DPRINTF("kvm_exit_exception\n");
+            fprintf(stderr, "KVM: unknown exit, hardware reason %" PRIx64 "\n",
+                    (uint64_t)run->hw.hardware_exit_reason);
             ret = -1;
             break;
 #ifdef KVM_CAP_INTERNAL_ERROR_DATA
diff --git a/target-i386/cpu.h b/target-i386/cpu.h
index dddcd74..a457423 100644
--- a/target-i386/cpu.h
+++ b/target-i386/cpu.h
@@ -874,6 +874,8 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
                    uint32_t *ecx, uint32_t *edx);
 int cpu_x86_register (CPUX86State *env, const char *cpu_model);
 void cpu_clear_apic_feature(CPUX86State *env);
+void host_cpuid(uint32_t function, uint32_t count,
+                uint32_t *eax, uint32_t *ebx, uint32_t *ecx, uint32_t *edx);
 
 /* helper.c */
 int cpu_x86_handle_mmu_fault(CPUX86State *env, target_ulong addr,
diff --git a/target-i386/cpuid.c b/target-i386/cpuid.c
index 165045e..5382a28 100644
--- a/target-i386/cpuid.c
+++ b/target-i386/cpuid.c
@@ -103,9 +103,8 @@ typedef struct model_features_t {
 int check_cpuid = 0;
 int enforce_cpuid = 0;
 
-static void host_cpuid(uint32_t function, uint32_t count,
-                       uint32_t *eax, uint32_t *ebx,
-                       uint32_t *ecx, uint32_t *edx)
+void host_cpuid(uint32_t function, uint32_t count,
+                uint32_t *eax, uint32_t *ebx, uint32_t *ecx, uint32_t *edx)
 {
 #if defined(CONFIG_KVM)
     uint32_t vec[4];
diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index ca4eb7a..684430f 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -1525,8 +1525,19 @@ static int kvm_handle_halt(CPUState *env)
     return 1;
 }
 
+static bool host_supports_vmx(void)
+{
+    uint32_t ecx, unused;
+
+    host_cpuid(1, 0, &unused, &unused, &ecx, &unused);
+    return ecx & CPUID_EXT_VMX;
+}
+
+#define VMX_INVALID_GUEST_STATE 0x80000021
+
 int kvm_arch_handle_exit(CPUState *env, struct kvm_run *run)
 {
+    uint64_t code;
     int ret = 0;
 
     switch (run->exit_reason) {
@@ -1534,6 +1545,28 @@ int kvm_arch_handle_exit(CPUState *env, struct kvm_run *run)
         DPRINTF("handle_hlt\n");
         ret = kvm_handle_halt(env);
         break;
+    case KVM_EXIT_FAIL_ENTRY:
+        code = run->fail_entry.hardware_entry_failure_reason;
+        fprintf(stderr, "KVM: entry failed, hardware error 0x%" PRIx64 "\n",
+                code);
+        if (host_supports_vmx() && code == VMX_INVALID_GUEST_STATE) {
+            fprintf(stderr,
+                    "\nIf you're runnning a guest on an Intel machine without "
+                        "unrestricted mode\n"
+                    "support, the failure can be most likely due to the guest "
+                        "entering an invalid\n"
+                    "state for Intel VT. For example, the guest maybe running "
+                        "in big real mode\n"
+                    "which is not supported on less recent Intel processors."
+                        "\n\n");
+        }
+        ret = -1;
+        break;
+    case KVM_EXIT_EXCEPTION:
+        fprintf(stderr, "KVM: exception %d exit (error code 0x%x)\n",
+                run->ex.exception, run->ex.error_code);
+        ret = -1;
+        break;
     default:
         fprintf(stderr, "KVM: unknown exit reason %d\n", run->exit_reason);
         ret = -1;
-- 
1.7.1

[Qemu-devel] [PATCH 6/6] kvm: x86: Prepare kvm_get_mp_state for in-kernel irqchip

[Jan Kiszka]

From: Jan Kiszka <jan.kiszka@siemens.com>

This code path will not yet be taken as we still lack in-kernel irqchip
support. But qemu-kvm can already make use of it and drop its own
mp_state access services.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---
 target-i386/kvm.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index 684430f..30aa51c 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -1198,6 +1198,9 @@ static int kvm_get_mp_state(CPUState *env)
         return ret;
     }
     env->mp_state = mp_state.mp_state;
+    if (kvm_irqchip_in_kernel()) {
+        env->halted = (mp_state.mp_state == KVM_MP_STATE_HALTED);
+    }
     return 0;
 }
 
-- 
1.7.1