These patches aim to solve two types of DMA-reentrancy issues:
1.) mmio -> dma -> mmio case
To solve this, we track whether the device is engaged in io by
checking/setting a reentrancy-guard within APIs used for MMIO access.
2.) bh -> dma write -> mmio case
This case is trickier, since we dont have a generic way to associate a
bh with the underlying Device/DeviceState. Thus, this version allows a
device to associate a reentrancy-guard with a bh, when creating it.
(Instead of calling qemu_bh_new, you call qemu_bh_new_guarded)
I replaced most of the qemu_bh_new invocations with the guarded analog,
except for the ones where the DeviceState was not trivially accessible
v4-> v5:
- Add corresponding checkpatch checks
- Save/restore reentrancy-flag when entering/exiting BHs
- Improve documentation
- Check object_dynamic_cast return value
v3 -> v4: Instead of changing all of the DMA APIs, instead add an
optional reentrancy guard to the BH API.
v2 -> v3: Bite the bullet and modify the DMA APIs, rather than
attempting to guess DeviceStates in BHs.
Alexander Bulekov (4):
memory: prevent dma-reentracy issues
async: Add an optional reentrancy guard to the BH API
checkpatch: add qemu_bh_new/aio_bh_new checks
hw: replace most qemu_bh_new calls with qemu_bh_new_guarded
docs/devel/multiple-iothreads.txt | 7 +++++++
hw/9pfs/xen-9p-backend.c | 4 +++-
hw/block/dataplane/virtio-blk.c | 3 ++-
hw/block/dataplane/xen-block.c | 5 +++--
hw/block/virtio-blk.c | 5 +++--
hw/char/virtio-serial-bus.c | 3 ++-
hw/display/qxl.c | 9 ++++++---
hw/display/virtio-gpu.c | 6 ++++--
hw/ide/ahci.c | 3 ++-
hw/ide/core.c | 3 ++-
hw/misc/imx_rngc.c | 6 ++++--
hw/misc/macio/mac_dbdma.c | 2 +-
hw/net/virtio-net.c | 3 ++-
hw/nvme/ctrl.c | 6 ++++--
hw/scsi/mptsas.c | 3 ++-
hw/scsi/scsi-bus.c | 3 ++-
hw/scsi/vmw_pvscsi.c | 3 ++-
hw/usb/dev-uas.c | 3 ++-
hw/usb/hcd-dwc2.c | 3 ++-
hw/usb/hcd-ehci.c | 3 ++-
hw/usb/hcd-uhci.c | 2 +-
hw/usb/host-libusb.c | 6 ++++--
hw/usb/redirect.c | 6 ++++--
hw/usb/xen-usb.c | 3 ++-
hw/virtio/virtio-balloon.c | 5 +++--
hw/virtio/virtio-crypto.c | 3 ++-
include/block/aio.h | 18 ++++++++++++++++--
include/hw/qdev-core.h | 7 +++++++
include/qemu/main-loop.h | 7 +++++--
scripts/checkpatch.pl | 8 ++++++++
softmmu/memory.c | 17 +++++++++++++++++
softmmu/trace-events | 1 +
tests/unit/ptimer-test-stubs.c | 3 ++-
util/async.c | 18 +++++++++++++++++-
util/main-loop.c | 5 +++--
util/trace-events | 1 +
36 files changed, 150 insertions(+), 43 deletions(-)
--
2.39.0
