On Fri, Jul 20, 2012 at 03:24:03AM +0200, Emmanuel Dreyfus wrote: > Hi > > I suspect I have another possible race between putpages and read. > > If page cache is used, VOP_PUTPAGES for PUFFS calls Fire-And-Forget > write operations. That means the kernel sends the write request and does > not wait for the reply. The kernel therefore has no way to know when > the operation completed.
If, nonetheless, the user processs returns inconsistent data for a subsequent read, that is a bug. In the user process, I would say. The user process *must* preserve ordering of reads and writes to the same underlying resource.
