Re: Filesystem corruption in current 9.99.92 (posix1eacl & log enabled FFSv2)

[Chuck Silvers <chuq%chuq.com@localhost>]

On Wed, Dec 29, 2021 at 08:01:53PM +0100, Matthias Petermann wrote:
> Hello,
> 
> On 27.12.21 06:20, Matthias Petermann wrote:
> > I did not try to move the file around as you recommended because I would
> > like to ask if there is anything I can do at this point to gather more
> > diagnostic data to help understand the root cause?
> 
> in the meantime I migrated all files to a freshly created filesystem using
> the patched kernel and so "solved" the problem for now.
> 
> The broken filesystem still exists, but I am now running out of space on the
> host (the filesystems are in sparse allocated VNDs). I would have to delete
> the broken filesystem in a timely manner, but would still like to run
> diagnostic steps on the root cause first, if any. Unfortunately, the
> filesystem is very large and remote, and I don't know how to reasonably
> isolate the affected portion to save space for further analysis. Are there
> any other reasonable steps I could do asap?

let me write something to allow you to extract the contents of the corrupted
extattr block, so that I can reproduce your exact situation on a test machine.
once we have a copy of the corrupted block then you can reclaim the existing
fs image.  hopefully I'll have that later today.

 
> One more question I would have about the patch. It helped very well to avoid
> the freeze when working in such a corrupted filesystem. In this case, the
> filesystem behaves as you described - no ACL is applied or issued on the
> affected directory. When I try to set a new ACL on the affected directory,
> it seems to have no effect, but no error message appears. Would it make
> sense to include the patch with appropriate error logging in the official
> sources, so that when the problem occurs for which we do not know the cause
> at the moment, we will at least get some output (instead of the current
> behavior - the infinite loop)?

yea, the final patch will include printing a message on the console, and
also include some way to restore the ability to set ACLs on the file
without needing to recreate the file (let alone recreating the whole fs).
that will take a little longer though.

-Chuck