Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote: > > > Expected behavior: > > > Punching holes in a file after splicing pages out of that file into a pipe > > > should not corrupt the spliced-out pages in the pipe buffer. I think this bit is the key. Why would this be the expected behaviour? As you say, splice is allowed to stuff parts of the pagecache into a pipe and these may get transferred, say, to a network card at the end to transmit directly from. It's a form of direct I/O. If someone has the pages mmapped, they can change the data that will be transmitted; if someone does a write(), they can change that data too. The point of splice is to avoid the copy - but it comes with a tradeoff. David
