On Thu, Mar 01, 2012 at 02:10:07PM -0800, Andrew Morton wrote: > > AFAIU i_mutex lock got added to hugetlbfs_read as per > > http://lkml.indiana.edu/hypermail/linux/kernel/0707.2/3066.html > > to take care of the race between truncate and read. This patch fix > > this by looking at page->mapping under page_lock (find_lock_page()) > > to ensure; the inode didn't get truncated in the range during a > > parallel read. > > > > Ideally we can extend the patch to make sure we don't increase i_size > > in mmap. But that will break userspace, because application will now > > have to use truncate(2) to increase i_size in hugetlbfs. > > Looks OK to me. > > Given that the bug has been there for four years, I'm assuming that > we'll be OK merging this fix into 3.4. Or we could merge it into 3.4 > and tag it for backporting into earlier kernels - it depends on whether > people are hurting from it, which I don't know? My testing hits this every day. It's not a real problem, but it's annoying to see the lockdep spew constantly. We've had a couple Fedora users report it too in regular day-to-day use as opposed to the hostile workloads I use to provoke it. FWIW, I'll probably throw it in the Fedora kernels, so if it ends up in stable, it'll be one less patch to carry. Dave -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>