On Mon 08-10-18 14:32:46, Eric Sandeen wrote: > In response to an earlier xfs patch to change how xfs reacts to > dax incompatibilities, Dave said: > > > I suspect we need to be more harsh are rejecting mounts with -o dax > > on devices DAX isn't supported on. This mount option is going into > > production systems - it's not just for "testing" as the comments all > > claim. i Things will break in production systems if DAX isn't > > enabled and they are expecting it to be enabled. > > and I tend to agree, so proposing this change to hard-fail a dax mount if > the device doesn't support it, instead of silently disabling the > functionality. Proposing for ext2, ext4, and xfs to keep behavior in > sync. Let me include Dan and Ross into the discussion since they were the ones proposing the "silent fallback" behavior (ext4 actually did fail the mount instead not so long ago - see 24f3478d664b "ext4: auto disable dax instead of failing mount" from December). Guys, why did you choose the fallback path instead of a failure? Honza -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR