I see a "STATUS_INVALID_PARAMETER" returned on tree connect from cifs.ko mounts (current 5.12-rc2 equivalent of cifs.ko running on 5.11) to current ksmbd (on 5.12). Here is the relevant dynamic trace entries: mount.cifs-20747 [002] .... 40007.155508: smb3_cmd_enter: sid=0x2 tid=0x0 cmd=3 mid=4 cifsd-20754 [001] .... 40007.156752: smb3_add_credits: conn_id=0xf server=10.0.0.0 {xN_FS_FREh\Nuse_delaؾ\~ current_mid=5 credits=127 credit_change=33 in_flight=0 mount.cifs-20747 [002] .... 40007.156969: smb3_cmd_err: sid=0x2 tid=0x0 cmd=3 mid=4 status=0xc000000d rc=-22 The wireshark trace shows very similar tree connects. The first to IPC$ which succeeds and the second which fails to the test share. Ideas? -- Thanks, Steve