On Mon, Jul 14, 2025 at 04:53:49PM +0100, John Garry wrote: > I see. I figure that something like a FS_XFLAG could be used for that. But > we should still protect bdev fops users as well. I'm not sure a XFLAG is all that useful. It's not really a per-file persistent thing. It's more of a mount option, or better persistent mount-option attr like we did for autofsck. > > JFYI, I have done a good bit of HW and SW-based atomic powerfail testing > with fio on a Linux dev board, so there is a decent method available for > users to verify their HW atomics. But then testing power failures is not > always practical. Crashing the kernel only tests AWUN, and AWUPF (for > NVMe). Yes. There's some ways to emulate power fail for file system level power fail testing using dm-log-writes and similar, but that doesn't help at all with testing the power fail behavior of the device which we rely on here.
