On Wed, Jun 27, 2018 at 04:05:29AM -0700, Matthew Wilcox wrote: > On Tue, Jun 19, 2018 at 10:16:38AM -0700, Matthew Wilcox wrote: > > I think I see a bug. No idea if it's the one you're hitting ;-) > > > > I had been intending to not use the 'entry' to decide whether we were > > waiting on a 2MB or 4kB page, but rather the xas. I shelved that idea, > > but not before dropping the DAX_PMD flag being passed from the PMD > > pagefault caller. So if I put that back ... > > Did you get a chance to test this? With this patch it doesn't deadlock, but the test dies with a SIGBUS and we hit a WARN_ON in the DAX code: WARNING: CPU: 5 PID: 1678 at fs/dax.c:226 get_unlocked_entry+0xf7/0x120 I don't have a lot of time this week to debug further. The quickest path to victory is probably for you to get this reproducing in your test setup. Does XFS + DAX + generic/340 pass for you?
