backtrace()
  tramp-signal-hook-function(file-error ("Timeout reached, see buffer ‘*tramp/ssh server1*’ ..."))
  signal(file-error ("Timeout reached, see buffer ‘*tramp/ssh server1*’ ..."))
  tramp-maybe-open-connection((tramp-file-name "ssh" nil nil "server1" nil "/home/hong" nil))
  tramp-send-command((tramp-file-name "ssh" nil nil "server1" nil "/home/hong" nil) "test 0 2>/dev/null; echo tramp_exit_status $?")
  tramp-send-command-and-check((tramp-file-name "ssh" nil nil "server1" nil "/home/hong" nil) "test 0")
  tramp-get-test-command((tramp-file-name "ssh" nil nil "server1" nil "/home/hong" nil))
  tramp-run-test("-d" "/ssh:server1:/home/hong")
  tramp-sh-handle-file-directory-p("/ssh:server1:/home/hong")
  apply(tramp-sh-handle-file-directory-p "/ssh:server1:/home/hong")
  tramp-sh-file-name-handler(file-directory-p "/ssh:server1:/home/hong")
  apply(tramp-sh-file-name-handler file-directory-p "/ssh:server1:/home/hong")
  tramp-file-name-handler(file-directory-p "/ssh:server1:/home/hong")
  file-directory-p("/ssh:server1:/home/hong")
  dired-noselect("/ssh:server1:/home/hong" nil)
  #f(compiled-function (dirname &optional switches) "\"Edit\" directory DIRNAME--delete, rename, print, etc. some files in it.\nOptional second argument SWITCHES specifies the `ls' options used.\n(Interactively, use a prefix argument to be able to specify SWITCHES.)\n\nIf DIRNAME is a string, Dired displays a list of files in DIRNAME (which\nmay also have shell wildcards appended to select certain files).\n\nIf DIRNAME is a cons, its first element is taken as the directory name\nand the rest as an explicit list of files to make directory entries for.\nIn this case, SWITCHES are applied to each of the files separately, and\ntherefore switches that control the order of the files in the produced\nlisting have no effect.\n\n\\<dired-mode-map>You can flag files for deletion with \\[dired-flag-file-deletion] and then\ndelete them by typing \\[dired-do-flagged-delete].\nType \\[describe-mode] after entering Dired for more info.\n\nIf DIRNAME is already in a Dired buffer, that buffer is used without refresh." (interactive (dired-read-dir-and-switches "")) #<bytecode 0x15902a876df9>)("/ssh:server1:/home/hong" nil)
  ls-lisp--dired(#f(compiled-function (dirname &optional switches) "\"Edit\" directory DIRNAME--delete, rename, print, etc. some files in it.\nOptional second argument SWITCHES specifies the `ls' options used.\n(Interactively, use a prefix argument to be able to specify SWITCHES.)\n\nIf DIRNAME is a string, Dired displays a list of files in DIRNAME (which\nmay also have shell wildcards appended to select certain files).\n\nIf DIRNAME is a cons, its first element is taken as the directory name\nand the rest as an explicit list of files to make directory entries for.\nIn this case, SWITCHES are applied to each of the files separately, and\ntherefore switches that control the order of the files in the produced\nlisting have no effect.\n\n\\<dired-mode-map>You can flag files for deletion with \\[dired-flag-file-deletion] and then\ndelete them by typing \\[dired-do-flagged-delete].\nType \\[describe-mode] after entering Dired for more info.\n\nIf DIRNAME is already in a Dired buffer, that buffer is used without refresh." (interactive (dired-read-dir-and-switches "")) #<bytecode 0x15902a876df9>) "/ssh:server1:/home/hong" nil)
  apply(ls-lisp--dired #f(compiled-function (dirname &optional switches) "\"Edit\" directory DIRNAME--delete, rename, print, etc. some files in it.\nOptional second argument SWITCHES specifies the `ls' options used.\n(Interactively, use a prefix argument to be able to specify SWITCHES.)\n\nIf DIRNAME is a string, Dired displays a list of files in DIRNAME (which\nmay also have shell wildcards appended to select certain files).\n\nIf DIRNAME is a cons, its first element is taken as the directory name\nand the rest as an explicit list of files to make directory entries for.\nIn this case, SWITCHES are applied to each of the files separately, and\ntherefore switches that control the order of the files in the produced\nlisting have no effect.\n\n\\<dired-mode-map>You can flag files for deletion with \\[dired-flag-file-deletion] and then\ndelete them by typing \\[dired-do-flagged-delete].\nType \\[describe-mode] after entering Dired for more info.\n\nIf DIRNAME is already in a Dired buffer, that buffer is used without refresh." (interactive (dired-read-dir-and-switches "")) #<bytecode 0x15902a876df9>) ("/ssh:server1:/home/hong" nil))
  dired("/ssh:server1:/home/hong" nil)
  funcall-interactively(dired "/ssh:server1:/home/hong" nil)
  call-interactively(dired nil nil)
  command-execute(dired)