On Sun, Apr 18, 2021 at 12:19:25PM -0400, Theodore Ts'o wrote: > The statement, "ext* and xfs have supported all variants of swap files > since their introduction, so swapon should not fail," is not quite > completely true. In particular, swapon does not work if the DAX is > active on a swapfile, and that would be true if the file system is > mounted with -o dax. > > So if swapon fails, check to see if the swapfile has the > STATX_ATTR_DAX attribute set, and if so, issue a _notrun instead of a > _fail. Isn't the fact that swapon doesn't work on DAX files a back? The swap I/O path couldn't care less if the file is marked as DAX or not.
