On 2014/11/12 5:37, Xie, Huawei wrote: > Hi Tetsuya: > There are two major technical issues in my mind for vhost-user implementation. > > 1) memory region map > Vhost-user passes us file fd and offset for each memory region. Unfortunately > the mmap offset is "very" wrong. I discovered this issue long time ago, and > also found > that I couldn't mmap the huge page file even with correct offset(need double > check). > Just now I find that people reported this issue on Nov 3. > [Qemu-devel] [PULL 27/29] vhost-user: fix mmap offset calculation > Anyway, I turned to the same idea used in our DPDK vhost-cuse: only use the > fd for region(0) to map the whole file. > I think we should use this way temporarily to support qemu-2.1 as it has that > bug. >
this bug is not in dpdk's vhost-user just for qemu's vhost-user backend > 2) what message is the indicator for vhost start/release? > Previously for vhost-cuse, it has SET_BACKEND message. > What we should do for vhost-user? > SET_VRING_KICK for start? > What about for release? > Unlike the kernel virtio, the DPDK virtio in guest could be restarted. > > Thoughts? > > -huawei > > -- Regards, Haifeng
