On Thu, Sep 01, 2011 at 04:09:49PM +1000, David Gibson wrote: > The virtio code already has memory barrier wmb() macros in the code. > However they are was defined as no-ops. The comment claims that real > barriers are not necessary because the code does not run concurrent. > However, with kvm and io-thread enabled, this is not true and this qemu > code can indeed run concurrently with the guest kernel. This does not > cause problems on x86 due to it's strongly ordered storage model, but it > causes a race leading to virtio errors on POWER which has a relaxed storage > ordering model.
Why not limit the change to ppc then? -- MST
