On Thu, May 04, 2023 at 05:55:56PM +0200, Jan Kara wrote: > For bdev address_space that's easy but what Ilya also mentioned is a > problem when 'stable_write' flag gets toggled on the device and in that > case having to propagate the flag update to all the address_space > structures is a nightmare... We have a number of flags which don't take effect when modified on a block device with a mounted filesystem on it. For example, modifying the readahead settings do not change existing files, only new ones. Since this flag is only modifiable for debugging purposes, I think I'm OK with it not affecting already-mounted filesystems. It feels like a decision that reasonable people could disagree on, though.