[Qemu-devel] [PATCHv4 0/3] virtio: fix memory access races

[Michael S. Tsirkin]

This is a follow-up to my previous patch: it turns
out that a single mb() isn't sufficient as network
loss could still be triggered under stress.

Changes from v3:
Make smp_rmb() with a compiler barrier on x86: reported by paolo.

Changes from v2:
Fix up GCC detection: reported by malc.
Fix barriers on PPC: reported by paolo.
Fix typo breaking bisect: reported by paolo.

Changes from v1:
Patch 1 is repost of v1.

The following two patches fix more races found
by code inspection and comparison with vhost
in kernel. After applying these
patches, no more network loss was observed.

Michael S. Tsirkin (3):
  virtio: add missing mb() on notification
  virtio: add missing mb() on enable notification
  virtio: order index/descriptor reads

 hw/virtio.c    |   11 +++++++++++
 qemu-barrier.h |   37 +++++++++++++++++++++++++++++++++----
 2 files changed, 44 insertions(+), 4 deletions(-)

-- 
MST