On 16-09-18 21:39, Richard Weinberger wrote:
Koen,
Am Samstag, 15. September 2018, 09:13:09 CEST schrieb Richard Weinberger:
Koen,
Am Dienstag, 11. September 2018, 16:26:34 CEST schrieb Koen Vandeputte:
On 2018-09-11 15:46, Koen Vandeputte wrote:
Hi Richard,
...
I'm only seeing these issues on UBIFS enabled volumes.
It seems it's related to one of your 5 commits, but I'm still in the
process of bisecting to find the actual culprit.
As soon as I've found it, I'll let you know, but maybe you already
have an idea here?
Reverting ("ubifs: xattr: Don't operate on deleted inodes") fixes the
weird issues.
Thanks for finding that bad commit!
I fear by fixing one bug I've uncovered another one.
So, I guess you are using overlayfs?
Which overlayfs features are you using?
I guess I've figured myself.
overlayfs is using temp files (O_TMPFILE), and a recent overlayfs
feature uses xattrs to indicate directory redirects.
So it can happen that a temp file, which has link count 0, gains
xattrs.
UBIFS models xattrs like regular files in directories. Since you cannot
add new files to a unlinked directory, UBIFS kind of enforced that for
xattrs too.
I say "kind of" because technically it works but can trigger an assertion
in UBIFS's journal code.
Recently I saw this assertion but failed to conclude that xattr operations on
unlinked files are perfectly fine and "fixed" the assert.
The right solution is reverting "ubifs: xattr: Don't operate on deleted inodes"
and removing the false positive asserts from UBIFS' journal code.
Sadly xfstests does not test for that, I'll prepare a new test case.
Maybe other file systems got this wrong too.
Thanks,
//richard
Hi Richard,
Apologies for the late reply.
It was a busy weekend with the kids ..
I'm very pleased to read you already have a good idea of what is going
on here.
Can I conclude you will provide a patch upstream to revert this specific
commit?
Please keep me in CC in case you do, so I can backport it properly into
OpenWrt on the next kernel bump. (until it is present in a future stable)
Once again, I highly appreciate you fast response in trying to get this
fixed.
Thank you Richard,
Koen
Reported-by: Koen Vandeputte <koen.vandeputte@xxxxxxxxxxxx>
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