On Mon, Feb 03, 2025 at 08:26:33AM +0000, Matthew Wilcox wrote: > so this is a block layer issue if it's not set. And even if the flag is set direct I/O ignores it. So while passing through such a flag through virtio might be useful we need to eventually sort out the fact that direct I/O doesn't respect it. Locking up any thread touching memory under direct I/O might be quite heavy handed, so this means bounce buffering on page fault. We had plenty of discussion of this before, but I don't think anyone actually looked into implementing it.
