On Thu, Oct 22, 2015 at 11:08:18PM +0200, Jan Kara wrote: > Ugh2: Now I realized that DAX mmap isn't safe wrt fs freezing even for > filesystems since there's nothing which writeprotects pages that are > writeably mapped. In normal path, page writeback does this but that doesn't > happen for DAX. I remember we once talked about this but it got lost. > We need something like walk all filesystem inodes during fs freeze and > writeprotect all pages that are mapped. But that's going to be slow...
fsync() has the same problem - we have no record of the pages that need to be committed and then write protected when fsync() is called after write()... Cheers, Dave. -- Dave Chinner da...@fromorbit.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
