borg crashes when backing up to gvfs volume about borg HOT 11 CLOSED

On kernel-based cifs volume borg check works fine. On gvfs with strace(1) attached to gvfs-fuse serving /run/user/2137/gvfs borg works fine. Without strace(1) it fails. From my experience this looks like some race condition in gvfs. But it is borg that is able to trigger it and that is interesting.

EDIT: borg check running under strace(1) also does not crash.

EVEN MORE EDIT: Even weirder is that the exception happens on the second attempt to open /run/user/2137/gvfs/smb-share:server=[snip],share=homefolder/steelman/Backup/Mail/lock.roster after asking for the password. The first successful attempt takes place right after startup.

from borg.

Your filesystem doesn't work correctly.

borg does a file "open" and the fs responds with:

OSError: [Errno 95] Operation not supported

from borg.

#7937 also had this issue.

from borg.

Indeed it looks very similar. However, it needs to be noted that:

a) it happens only with borg check and not with borg create
b) I can open() files for writing on this file system (especially inside the borg repository) without any problems.

from borg.

You can try to reproduce this on a local filesystem to see whether it only happens on cifs.

"not supported" as error response to "open()" is weird.

from borg.

Oh, and try without that "gvfs" and just do a normal cifs mount and try with that also.

from borg.

I played with touch(1) and strace(1). The former randomly fails to create files in /run/user/2137/gvfs/smb-share:server=[snip],share=homefolder/steelman/Backup/Mail/ (with EOPNOTSUPP) so it seems there is little chance this isn't a fault of gvfs. I will keep investigating.

EDIT: No, it's not at random. openat(2) sets errno to EOPNOTSUPP when the file to be created exists. The first call succeeds:

openat(AT_FDCWD, "/run/user/2137/gvfs/smb-share:server=[snip],share=homefolder/steelman/Backup/Mail/__test__", O_WRONLY|O_CREAT|O_NOCTTY|O_NONBLOCK, 0666) = 3

consequent fail:

openat(AT_FDCWD, "/run/user/2137/gvfs/smb-share:server=[snip],share=homefolder/steelman/Backup/Mail/__test__", O_WRONLY|O_CREAT|O_NOCTTY|O_NONBLOCK, 0666) = -1 EOPNOTSUPP (Operation not supported)

from borg.

OK, so guess this is a gvfs bug? Or is borg doing something wrong or unusual?

from borg.

It looks like a gvfs bug to me, but this is just like, my opinion. I will find out.

from borg.

Guess this is a gvfs bug.

from borg.

Indeed, I still haven't found out why it occurs but at least borg stopped triggering for me.

from borg.