block/monitor: Fix crash when executing HMP commit

hmp_commit() calls blk_is_available() from a non-coroutine context (and
in the main loop). blk_is_available() is a co_wrapper_mixed_bdrv_rdlock
function, and in the non-coroutine context it calls AIO_WAIT_WHILE(),
which crashes if the aio_context lock is not taken before.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1615
Signed-off-by: Wang Liang <wangliangzz@inspur.com>
Message-Id: <20230424103902.45265-1-wangliangzz@126.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
(cherry picked from commit 8c1e8fb2e7)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

block/monitor/block-hmp-cmds.c

@@ -214,15 +214,17 @@ void hmp_commit(Monitor *mon, const QDict *qdict)
             error_report("Device '%s' not found", device);
             return;
         }
-        if (!blk_is_available(blk)) {
-            error_report("Device '%s' has no medium", device);
-            return;
-        }
 
         bs = bdrv_skip_implicit_filters(blk_bs(blk));
         aio_context = bdrv_get_aio_context(bs);
         aio_context_acquire(aio_context);
 
+        if (!blk_is_available(blk)) {
+            error_report("Device '%s' has no medium", device);
+            aio_context_release(aio_context);
+            return;
+        }
+
         ret = bdrv_commit(bs);
 
         aio_context_release(aio_context);

hw/acpi/pcihp.c

@@ -357,6 +357,16 @@ void acpi_pcihp_device_unplug_request_cb(HotplugHandler *hotplug_dev,
      * acpi_pcihp_eject_slot() when the operation is completed.
      */
     pdev->qdev.pending_deleted_event = true;
+    /* if unplug was requested before OSPM is initialized,
+     * linux kernel will clear GPE0.sts[] bits during boot, which effectively
+     * hides unplug event. And than followup qmp_device_del() calls remain
+     * blocked by above flag permanently.
+     * Unblock qmp_device_del() by setting expire limit, so user can
+     * repeat unplug request later when OSPM has been booted.
+     */
+    pdev->qdev.pending_deleted_expires_ms =
+        qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL); /* 1 msec */
+
     s->acpi_pcihp_pci_status[bsel].down |= (1U << slot);
     acpi_send_event(DEVICE(hotplug_dev), ACPI_PCI_HOTPLUG_STATUS);
 }

hw/s390x/virtio-ccw.c

@@ -237,6 +237,7 @@ static int virtio_ccw_set_vqs(SubchDev *sch, VqInfoBlock *info,
                 return -EINVAL;
             }
             virtio_queue_set_num(vdev, index, num);
+            virtio_init_region_cache(vdev, index);
         } else if (virtio_queue_get_num(vdev, index) > num) {
             /* Fail if we don't have a big enough queue. */
             return -EINVAL;

hw/timer/imx_epit.c

@@ -179,7 +179,7 @@ static void imx_epit_update_compare_timer(IMXEPITState *s)
          * the compare value. Otherwise it may fire at most once in the
          * current round.
          */
-        bool is_oneshot = (limit >= s->cmp);
+        is_oneshot = (limit < s->cmp);
         if (counter >= s->cmp) {
             /* The compare timer fires in the current round. */
             counter -= s->cmp;

hw/virtio/virtio-mmio.c

@@ -354,6 +354,7 @@ static void virtio_mmio_write(void *opaque, hwaddr offset, uint64_t value,
         if (proxy->legacy) {
             virtio_queue_update_rings(vdev, vdev->queue_sel);
         } else {
+            virtio_init_region_cache(vdev, vdev->queue_sel);
             proxy->vqs[vdev->queue_sel].num = value;
         }
         break;

hw/virtio/virtio-pci.c

@@ -1554,6 +1554,7 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr,
         proxy->vqs[vdev->queue_sel].num = val;
         virtio_queue_set_num(vdev, vdev->queue_sel,
                              proxy->vqs[vdev->queue_sel].num);
+        virtio_init_region_cache(vdev, vdev->queue_sel);
         break;
     case VIRTIO_PCI_COMMON_Q_MSIX:
         vector = virtio_queue_vector(vdev, vdev->queue_sel);

hw/virtio/virtio.c

@@ -226,7 +226,7 @@ static void virtio_virtqueue_reset_region_cache(struct VirtQueue *vq)
     }
 }
 
-static void virtio_init_region_cache(VirtIODevice *vdev, int n)
+void virtio_init_region_cache(VirtIODevice *vdev, int n)
 {
     VirtQueue *vq = &vdev->vq[n];
     VRingMemoryRegionCaches *old = vq->vring.caches;

include/hw/virtio/virtio.h

@@ -309,6 +309,7 @@ int virtio_get_num_queues(VirtIODevice *vdev);
 void virtio_queue_set_rings(VirtIODevice *vdev, int n, hwaddr desc,
                             hwaddr avail, hwaddr used);
 void virtio_queue_update_rings(VirtIODevice *vdev, int n);
+void virtio_init_region_cache(VirtIODevice *vdev, int n);
 void virtio_queue_set_align(VirtIODevice *vdev, int n, int align);
 void virtio_queue_notify(VirtIODevice *vdev, int n);
 uint16_t virtio_queue_vector(VirtIODevice *vdev, int n);

target/i386/cpu.c

@@ -5718,8 +5718,8 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
         } else {
             *eax &= env->features[FEAT_SGX_12_1_EAX];
             *ebx &= 0; /* ebx reserve */
-            *ecx &= env->features[FEAT_XSAVE_XSS_LO];
-            *edx &= env->features[FEAT_XSAVE_XSS_HI];
+            *ecx &= env->features[FEAT_XSAVE_XCR0_LO];
+            *edx &= env->features[FEAT_XSAVE_XCR0_HI];
 
             /* FP and SSE are always allowed regardless of XSAVE/XCR0. */
             *ecx |= XSTATE_FP_MASK | XSTATE_SSE_MASK;

ui/vnc.c

@@ -3751,7 +3751,7 @@ static int vnc_display_get_address(const char *addrstr,
 
         addr->type = SOCKET_ADDRESS_TYPE_INET;
         inet = &addr->u.inet;
-        if (addrstr[0] == '[' && addrstr[hostlen - 1] == ']') {
+        if (hostlen && addrstr[0] == '[' && addrstr[hostlen - 1] == ']') {
             inet->host = g_strndup(addrstr + 1, hostlen - 2);
         } else {
             inet->host = g_strndup(addrstr, hostlen);