On Thu, May 11, 2017 at 03:56:35PM -0400, Chris Mason wrote: > On 05/11/2017 03:52 PM, Jeff Layton wrote: > > On Thu, 2017-05-11 at 07:13 -0400, Jeff Layton wrote: > > > I finally got my writeback error handling test to work on btrfs (thanks, > > > Chris!), by making the filesystem stripe the data and mirror the > > > metadata across two devices. The test passes now, but on one run, I got > > > the following list corruption warning and then a soft lockup (which is > > > probably fallout from the list corruption). > > > > > > I ran the test several times before and since then without this failure, > > > so I don't have a clear reproducer. The kernel in this instance is > > > basically a v4.11 kernel with my pile of writeback error handling > > > patches on top: > > > > > > > > > https://urldefense.proofpoint.com/v2/url?u=https-3A__git.samba.org_-3Fp-3Djlayton_linux.git-3Ba-3Dshortlog-3Bh-3Drefs_heads_wberr&d=DwICaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=9QPtTAxcitoznaWRKKHoEQ&m=BXXwaUFQNFNaGGFYHEVlvNBwkrXiIoH7K5iOdR_PvxM&s=xE6pIXeQ1rlaxAV8aTYBSiI06pb3WZoiRJW8Vo1L3NQ&e= > > > > > > It may be that they are a contributing factor, but this smells more like > > > a bug down in btrfs. Let me know if you need other info: > > [ btrfs inode logging ] > > > (cc'ing Liu Bo since we were discussing this earlier this week) > > > > I can't reproduce this on stock v4.11, so I think this is a bug in my > > series. > > > > I think this is due to the differences in how errors are being reported > > from filemap_fdatawait_range now causing some transactions to end up > > being freed while they're still on the log_ctxs list. I'm working on > > hunting down the problem now. > > > > Sorry for the noise! > > > > There's a list in the inode logging code that we consistently seem to find > list debugging assertions with. We've fixed up all the known issues, but I > wouldn't be surprised if we've got a goto fail in there. > > I'll take a look ;)
FYI, I've nailed this down, and it turns out to be a bug from btrfs side[1]. [1] https://patchwork.kernel.org/patch/10056535/ "Btrfs: fix list_add corruption and soft lockups in fsync" Thanks, -liubo -- 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
