Re: [PATCH v8 12/12] tests/vm: Add workaround to consume console

[Philippe Mathieu-Daudé]

On 5/29/20 10:34 PM, Robert Foley wrote:
> This adds support to basevm.py so that we always
> drain the console chars.  This makes use of
> support added in an earlier commit that allows
> QEMUMachine to use the ConsoleSocket.
> 
> This is a workaround we found was needed since
> there is a known issue where QEMU will hang waiting
> for console characters to be consumed.
> 
> We also added the option of logging the console to a file.
> LOG_CONSOLE=1 will now log the output to a file.
> 
> Signed-off-by: Robert Foley <robert.foley@linaro.org>
> Reviewed-by: Peter Puhov <peter.puhov@linaro.org>
> Acked-by: Alex Bennée <alex.bennee@linaro.org>
> ---
>  tests/vm/Makefile.include |  4 ++++
>  tests/vm/basevm.py        | 17 +++++++++++++++--
>  2 files changed, 19 insertions(+), 2 deletions(-)
> 
> diff --git a/tests/vm/Makefile.include b/tests/vm/Makefile.include
> index 8cccfaf95d..ad35c6e7a1 100644
> --- a/tests/vm/Makefile.include
> +++ b/tests/vm/Makefile.include
> @@ -49,6 +49,7 @@ endif
>       @echo '    EXTRA_CONFIGURE_OPTS="..."'
>       @echo "    J=[0..9]*                     - Override the -jN parameter 
> for make commands"
>       @echo "    DEBUG=1                       - Enable verbose output on 
> host and interactive debugging"
> +     @echo "    LOG_CONSOLE=1                 - Log console to file in: 
> ~/.cache/qemu-vm "
>       @echo "    V=1                           - Enable verbose ouput on host 
> and guest commands"
>       @echo "    QEMU_LOCAL=1                 - Use QEMU binary local to this 
> build."
>       @echo "    QEMU=/path/to/qemu            - Change path to QEMU binary"
> @@ -75,6 +76,7 @@ $(IMAGES_DIR)/%.img:        $(SRC_PATH)/tests/vm/% \
>               $(if $(GENISOIMAGE),--genisoimage $(GENISOIMAGE)) \
>               $(if $(QEMU_LOCAL),--build-path $(BUILD_DIR)) \
>               $(if $(EFI_AARCH64),--efi-aarch64 $(EFI_AARCH64)) \
> +             $(if $(LOG_CONSOLE),--log-console) \
>               --image "$@" \
>               --force \
>               --build-image $@, \
> @@ -91,6 +93,7 @@ vm-build-%: $(IMAGES_DIR)/%.img
>               $(if $(V),--verbose) \
>               $(if $(QEMU_LOCAL),--build-path $(BUILD_DIR)) \
>               $(if $(EFI_AARCH64),--efi-aarch64 $(EFI_AARCH64)) \
> +             $(if $(LOG_CONSOLE),--log-console) \
>               --image "$<" \
>               $(if $(BUILD_TARGET),--build-target $(BUILD_TARGET)) \
>               --snapshot \
> @@ -114,6 +117,7 @@ vm-boot-ssh-%: $(IMAGES_DIR)/%.img
>               $(if $(V)$(DEBUG), --debug) \
>               $(if $(QEMU_LOCAL),--build-path $(BUILD_DIR)) \
>               $(if $(EFI_AARCH64),--efi-aarch64 $(EFI_AARCH64)) \
> +             $(if $(LOG_CONSOLE),--log-console) \
>               --image "$<" \
>               --interactive \
>               false, \
> diff --git a/tests/vm/basevm.py b/tests/vm/basevm.py
> index b9d828423b..64dbe64326 100644
> --- a/tests/vm/basevm.py
> +++ b/tests/vm/basevm.py
> @@ -117,6 +117,11 @@ class BaseVM(object):
>               "w").write(self._config['ssh_pub_key'])
>  
>          self.debug = args.debug
> +        self._console_log_path = None
> +        if args.log_console:
> +                self._console_log_path = \
> +                         os.path.join(os.path.expanduser("~/.cache/qemu-vm"),
> +                                      "{}.install.log".format(self.name))
>          self._stderr = sys.stderr
>          self._devnull = open(os.devnull, "w")
>          if self.debug:
> @@ -271,7 +276,9 @@ class BaseVM(object):
>          args += self._data_args + extra_args + self._config['extra_args']
>          logging.debug("QEMU args: %s", " ".join(args))
>          qemu_path = get_qemu_path(self.arch, self._build_path)
> -        guest = QEMUMachine(binary=qemu_path, args=args)
> +        guest = QEMUMachine(binary=qemu_path, args=args,
> +                            console_log=self._console_log_path,
> +                            drain_console=True)

Are you sure you need to set drain_console here? Isn't it implied by
self._console_log_path?

>          guest.set_machine(self._config['machine'])
>          guest.set_console()
>          try:
> @@ -285,6 +292,8 @@ class BaseVM(object):
>              raise
>          atexit.register(self.shutdown)
>          self._guest = guest
> +        # Init console so we can start consuming the chars.
> +        self.console_init()
>          usernet_info = guest.qmp("human-monitor-command",
>                                   command_line="info usernet")
>          self.ssh_port = None
> @@ -296,7 +305,9 @@ class BaseVM(object):
>              raise Exception("Cannot find ssh port from 'info usernet':\n%s" 
> % \
>                              usernet_info)
>  
> -    def console_init(self, timeout = 120):
> +    def console_init(self, timeout = None):
> +        if timeout == None:
> +            timeout = self.socket_timeout
>          vm = self._guest
>          vm.console_socket.settimeout(timeout)
>          self.console_raw_path = os.path.join(vm._temp_dir,
> @@ -578,6 +589,8 @@ def parse_args(vmcls):
>      parser.add_option("--efi-aarch64",
>                        default="/usr/share/qemu-efi-aarch64/QEMU_EFI.fd",
>                        help="Path to efi image for aarch64 VMs.")
> +    parser.add_option("--log-console", action="store_true",
> +                      help="Log console to file.")
>      parser.disable_interspersed_args()
>      return parser.parse_args()
>  
>