On 2015-07-15 17:29, Chris Murphy wrote: > On Wed, Jul 15, 2015 at 10:15 AM, Hugo Mills wrote: > >> There is at least one superblock on every device, usually two, and >> often three. Each superblock contains the virtual address of the roots >> of the root tree, the chunk tree and the log tree. Those are useless >> without having the chunk tree, so there's also some information about >> the chunk tree appended to the end of each superblock to bootstrap the >> virtual address space lookup. > > So maybe Austin can use btrfs-show-super -a on every device and see if > there's anything different on some of the devices, that shouldn't be > different? There must be something the kernel is tripping over that > the use space tools aren't for some reason. > > > > I actually did do so when this happened most recently (I just didn't think to mention it in the most recent e-mail), and nothing appeared to be different either between devices or within a given device (IIRC, there's 2 sb per device in each of the filesystems in question). I'm going to try and reproduce this in a VM for inspection as all the filesystems I had this issue with now seem to be working fine (with the exception of some errors in the data blocks of one that got caught by scrub).