From: Emanuele Giuseppe Esposito <eespo...@redhat.com> All the callbacks below are always running in the main loop.
The callbacks are the following: - start/stop_ioeventfd: these are the callbacks where blk_set_aio_context(iothread) is done, so they are called in the main loop. - save and load: called during migration, when VM is stopped from the main loop. - reset: before calling this callback, stop_ioeventfd is invoked, so it can only run in the main loop. - set_status: going through all the callers we can see it is called from a MemoryRegionOps callback, which always run in a vcpu thread and hold the BQL. - realize: iothread is not even created yet. Signed-off-by: Emanuele Giuseppe Esposito <eespo...@redhat.com> Reviewed-by: Stefan Hajnoczi <stefa...@redhat.com> Acked-by: Michael S. Tsirkin <m...@redhat.com> Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com> Message-Id: <20220609143727.1151816-5-eespo...@redhat.com> --- hw/block/virtio-blk.c | 2 ++ hw/virtio/virtio-bus.c | 5 +++++ hw/virtio/virtio-pci.c | 2 ++ hw/virtio/virtio.c | 8 ++++++++ 4 files changed, 17 insertions(+) diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index 96d00103a4..96bc11d2fe 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -1005,6 +1005,8 @@ static void virtio_blk_set_status(VirtIODevice *vdev, uint8_t status) { VirtIOBlock *s = VIRTIO_BLK(vdev); + GLOBAL_STATE_CODE(); + if (!(status & (VIRTIO_CONFIG_S_DRIVER | VIRTIO_CONFIG_S_DRIVER_OK))) { assert(!s->dataplane_started); } diff --git a/hw/virtio/virtio-bus.c b/hw/virtio/virtio-bus.c index 896feb37a1..74cdf4bd27 100644 --- a/hw/virtio/virtio-bus.c +++ b/hw/virtio/virtio-bus.c @@ -23,6 +23,7 @@ */ #include "qemu/osdep.h" +#include "qemu/main-loop.h" #include "qemu/error-report.h" #include "qemu/module.h" #include "qapi/error.h" @@ -224,6 +225,8 @@ int virtio_bus_start_ioeventfd(VirtioBusState *bus) VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev); int r; + GLOBAL_STATE_CODE(); + if (!k->ioeventfd_assign || !k->ioeventfd_enabled(proxy)) { return -ENOSYS; } @@ -248,6 +251,8 @@ void virtio_bus_stop_ioeventfd(VirtioBusState *bus) VirtIODevice *vdev; VirtioDeviceClass *vdc; + GLOBAL_STATE_CODE(); + if (!bus->ioeventfd_started) { return; } diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c index a1c9dfa7bb..4f9a94f61b 100644 --- a/hw/virtio/virtio-pci.c +++ b/hw/virtio/virtio-pci.c @@ -313,6 +313,8 @@ static void virtio_ioport_write(void *opaque, uint32_t addr, uint32_t val) uint16_t vector; hwaddr pa; + GLOBAL_STATE_CODE(); + switch (addr) { case VIRTIO_PCI_GUEST_FEATURES: /* Guest does not negotiate properly? We have to assume nothing. */ diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 9683b2e158..468e8f5ad0 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -2422,6 +2422,8 @@ int virtio_set_status(VirtIODevice *vdev, uint8_t val) VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); trace_virtio_set_status(vdev, val); + GLOBAL_STATE_CODE(); + if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) { if (!(vdev->status & VIRTIO_CONFIG_S_FEATURES_OK) && val & VIRTIO_CONFIG_S_FEATURES_OK) { @@ -2515,6 +2517,8 @@ void virtio_reset(void *opaque) VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); int i; + GLOBAL_STATE_CODE(); + virtio_set_status(vdev, 0); if (current_cpu) { /* Guest initiated reset */ @@ -3357,6 +3361,8 @@ int virtio_save(VirtIODevice *vdev, QEMUFile *f) uint32_t guest_features_lo = (vdev->guest_features & 0xffffffff); int i; + GLOBAL_STATE_CODE(); + if (k->save_config) { k->save_config(qbus->parent, f); } @@ -3508,6 +3514,8 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id) VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev); + GLOBAL_STATE_CODE(); + /* * We poison the endianness to ensure it does not get used before * subsections have been loaded. -- 2.38.1