Hi all, It is a curiosity question rather a bug/issue report.
Linux DMA subsystem wants streaming DMA buffers to be synchronized before accessing them. This is achieved by calling dma_sync_* family of functions. And, I see that these functions are used in kernel clients (e.g. xprtrdma, and iSER). This is all fine. During memory memory registration, userspace buffers also go through same API calls (dma_map_sg_attrs(...)). What I am confused about why no such synchronization primitives are required in userspace before accessing an RDMA data buffer just after when an incoming write/recv (DMA on it) is finished? Who guarantees data freshness? Thanks, -- Animesh -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
