On Thu, Jun 15, 2023 at 11:51:09PM +0000, Wengang Wang wrote: > > > > On Jun 15, 2023, at 4:33 PM, Dave Chinner <david@xxxxxxxxxxxxx> wrote: > > > > On Thu, Jun 15, 2023 at 11:09:41PM +0000, Wengang Wang wrote: > >> When mounting the problematic metadump with the patches, I see the following reported. > >> > >> For more information about troubleshooting your instance using a console connection, see the documentation: https://docs.cloud.oracle.com/en-us/iaas/Content/Compute/References/serialconsole.htm#four > >> ================================================= > >> [ 67.212496] loop: module loaded > >> [ 67.214732] loop0: detected capacity change from 0 to 629137408 > >> [ 67.247542] XFS (loop0): Deprecated V4 format (crc=0) will not be supported after September 2030. > >> [ 67.249257] XFS (loop0): Mounting V4 Filesystem af755a98-5f62-421d-aa81-2db7bffd2c40 > >> [ 72.241546] XFS (loop0): Starting recovery (logdev: internal) > >> [ 92.218256] XFS (loop0): Internal error ltbno + ltlen > bno at line 1957 of file fs/xfs/libxfs/xfs_alloc.c. Caller xfs_free_ag_extent+0x3f6/0x870 [xfs] > >> [ 92.249802] CPU: 1 PID: 4201 Comm: mount Not tainted 6.4.0-rc6 #8 > > > > What is the test you are running? Please describe how you reproduced > > this failure - a reproducer script would be the best thing here. > > I was mounting a (copy of) V4 metadump from customer. Is the metadump obfuscated? Can I get a copy of it via a private, secure channel? > > Does the test fail on a v5 filesytsem? > > N/A. > > > > >> I think that’s because that the same EFI record was going to be freed again > >> by xfs_extent_free_finish_item() after it already got freed by xfs_efi_item_recover(). How is this happening? Where (and why) are we defering an extent we have successfully freed into a new xefi that we create a new intent for and then defer? Can you post the debug output and analysis that lead you to this observation? I certainly can't see how this can happen from looking at the code > >> I was trying to fix above issue in my previous patch by checking the intent > >> log item’s lsn and avoid running iop_recover() in xlog_recover_process_intents(). > >> > >> Now I am thinking if we can pass a flag, say XFS_EFI_PROCESSED, from > >> xfs_efi_item_recover() after it processed that record to the xfs_efi_log_item > >> memory structure somehow. In xfs_extent_free_finish_item(), we skip to process > >> that xfs_efi_log_item on seeing XFS_EFI_PROCESSED and return OK. By that > >> we can avoid the double free. > > > > I'm not really interested in speculation of the cause or the fix at > > this point. I want to know how the problem is triggered so I can > > work out exactly what caused it, along with why we don't have > > coverage of this specific failure case in fstests already. > > > > I get to know the cause by adding additional debug log along with > my previous patch. Can you please post that debug and analysis, rather than just a stack trace that is completely lacking in context? Nothing can be inferred from a stack trace, and what you are saying is occurring does not match what the code should actually be doing. So I need to actually look at what is happening in detail to work out where this mismatch is coming from.... -Dave. -- Dave Chinner david@xxxxxxxxxxxxx
