Verification for disco. I went and installed 5.0.0-40-generic from -proposed to a disco box:
$ uname -rv 5.0.0-40-generic #44-Ubuntu SMP Wed Jan 15 02:03:45 UTC 2020 I do not have access to a multi tier cifs mount, so I will try and connect to a known one with a bad username / password to ensure that the server forwarding and caching works as expected, since that occurs before authentication. I enabled tracing with: # modprobe cifs # echo 'module cifs +p' > /sys/kernel/debug/dynamic_debug/control # echo 'file fs/cifs/* +p' > /sys/kernel/debug/dynamic_debug/control # echo 7 > /proc/fs/cifs/cifsFYI To mount a cifs share, you need cifs-utils: $ sudo apt install cifs-utils >From there I accessed the multi tier cifs server: $ sudo mount -v -t cifs //<domain>/<toplevel>/<country>/<sharename> -o defaults,user=aaa /mnt/share Checking dmesg we get: Status code returned 0xc0000257 STATUS_PATH_NOT_COVERED fs/cifs/smb2maperror.c: Mapping SMB2 status code 0xc0000257 to POSIX err -66 fs/cifs/connect.c: build_unc_path_to_root: full_path=\\<Regional DFS Server>\Root\Country\<Share> fs/cifs/connect.c: build_unc_path_to_root: full_path=\\<Regional DFS Server>\Root\Country\<Share> fs/cifs/dfs_cache.c: do_dfs_cache_find: search path: \<Regional DFS Server>\Root\Country\<Share> fs/cifs/dfs_cache.c: do_dfs_cache_find: cache miss fs/cifs/dfs_cache.c: do_dfs_cache_find: DFS referral request for \<Actual DFS Server>\Root\Country\<Share> fs/cifs/smb2ops.c: smb2_get_dfs_refer path <\<Actual DFS Server>\Root\Country\<Share>> fs/cifs/misc.c: num_referrals: 1 dfs flags: 0x2 ... fs/cifs/dns_resolve.c: dns_resolve_server_name_to_ip: resolved: <Actual File Server> to <IPV4 Address> fs/cifs/connect.c: Username: aaa This is in line with what is expected, since it resolves the next tier file server instead of failing and going back up the tree. I had also previously supplied the customer with a test build based on the previous bionic hwe kernel, 5.0.0-37-generic #40~18.04.1, with the commit applied, and all was tested and working. With my verification of disco kernel from -proposed the customer's prior test kernel, I am happy to mark this as verified. Next, I just need this patch to land in eoan, and then into a bionic HWE kernel to get this fixed for the customer. ** Tags removed: verification-needed-disco ** Tags added: verification-done-disco -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1854887 Title: cifs: DFS Caching feature causing problems traversing multi-tier DFS setups To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1854887/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
