Resurrecting this old thread because I'm still seeing these errors. On Thu, Mar 16, 2017 at 6:54 PM, Qu Wenruo <quwen...@cn.fujitsu.com> wrote: > > > At 03/17/2017 07:22 AM, Chris Murphy wrote: >> >> With kernel 4.10.3, and btrfs-progs 4.10, I'm still seeing the >> following errors only with --mode=lowmem with a single device volume. >> >> >> ERROR: data extent[16913485824 7577600] backref lost >> (hundreds of lines of the same thing) >> >> btrfs-image (no errors reported during capture) 518MiB >> https://drive.google.com/open?id=0B7NttHfq6wAJd3ZXM3AxS0dVQlU > > > Thanks a lot for the image. > > Turns out to be that, lowmem mode only checks EXTENT_DATA_REF key, and > doesn't check SHARED_DATA_REF_KEY, this leads to the error message. > > Fix will be sent out soon.
I'm using btrfs-progs 4.13.3 and still see these errors. Do you need an updated sanitized image, or newer version or patchset to test? This example error is happening on a single device volume with DUP metadata, and also ends in a crash:. ERROR: data extent[16913485824 7577600] backref lost ... backref.c:466: __add_missing_keys: Assertion `ref->root_id` failed, value 0 ... Complete output, with filtered btrfs-debug-tree info for extent address 16913485824 https://drive.google.com/open?id=1WgHdIz7zu_bO6evUBkG4wPxpJfwaFCxv ------ This example error is happening on a two device raid1 data and raid1 metadata volume: ERROR: extent[366498091008, 134217728] referencer count mismatch (root: 827, owner: 73782, offset: 134217728) wanted: 4, have: 26 Complete output, with filtered btrfs-debug-tree info for extent address 366498091008. https://drive.google.com/open?id=1LUMtLIc1LcXhYN3twFcxTyFuJ6ScMlyQ Both examples have multiple extents reported in the error but I've only included debug tree info for the first extent listed by lowmem check. So it's an incomplete report. I can provide sanitized btrfs-image on request, or test with patches. -- Chris Murphy -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
