2026-09-12 –, D.0.07
You don't like concurrency and you liked it better when only one kernel could be running at a time on one CPU. You got comfortable using mutexes and condition variables to make things go one at a time. But your packets keep getting stuck, and the hair raises on the back of your head as you begin to suspect you'll have to think about memory ordering in a device driver that got ported sloppily from Linux. What now?
This talk will discuss the bus_dma(9) model of memory ordering, obscure issues in paravirtualization, incoherent mappings on different architectures, and tools that a hacker can use to formally verify their memory ordering -- along with limitations of those tools.
Taylor ‘Riastradh’ Campbell has been a NetBSD developer since 2011,
working on various areas including cryptography, device drivers, and
multiprocessor safety, and is a member of the NetBSD core team and The
NetBSD Foundation board.