Gerd Hoffmann <[email protected]> writes:
> Starting with the edk2-stable202508 tag OVMF (and ArmVirt too) have
> optional support for logging to a memory buffer. There is guest side
> support -- for example in linux kernels v6.17+ -- to read that buffer.
> But that might not helpful if your guest stops booting early enough that
> guest tooling can not be used yet. So host side support to read that
> log buffer is a useful thing to have.
>
> This patch implements both qmp and hmp monitor commands to read the
> firmware log.
>
> Signed-off-by: Gerd Hoffmann <[email protected]>
[...]
> diff --git a/tests/qtest/qmp-cmd-test.c b/tests/qtest/qmp-cmd-test.c
> index cf718761861d..ffdb7e979e0f 100644
> --- a/tests/qtest/qmp-cmd-test.c
> +++ b/tests/qtest/qmp-cmd-test.c
> @@ -52,6 +52,8 @@ static int query_error_class(const char *cmd)
> /* Only valid with accel=tcg */
> { "x-query-jit", ERROR_CLASS_GENERIC_ERROR },
> { "xen-event-list", ERROR_CLASS_GENERIC_ERROR },
> + /* requires firmware with memory buffer logging support */
> + { "query-ovmf-log", ERROR_CLASS_GENERIC_ERROR },
> { NULL, -1 }
> };
> int i;
Makes sense.
> diff --git a/hmp-commands-info.hx b/hmp-commands-info.hx
> index 6142f60e7b16..eca0614903d1 100644
> --- a/hmp-commands-info.hx
> +++ b/hmp-commands-info.hx
> @@ -977,3 +977,16 @@ SRST
> ``info cryptodev``
> Show the crypto devices.
> ERST
> +
> + {
> + .name = "ovmf-log",
> + .args_type = "",
> + .params = "",
> + .help = "show the ovmf debug log",
> + .cmd_info_hrt = qmp_query_ovmf_log,
> + },
> +
> +SRST
> + ``info ovmf-log``
> + Show the ovmf debug log.
> +ERST
> diff --git a/hw/uefi/meson.build b/hw/uefi/meson.build
> index 91eb95f89e6d..c8f38dfae247 100644
> --- a/hw/uefi/meson.build
> +++ b/hw/uefi/meson.build
> @@ -1,4 +1,4 @@
> -system_ss.add(files('hardware-info.c'))
> +system_ss.add(files('hardware-info.c', 'ovmf-log.c'))
>
> uefi_vars_ss = ss.source_set()
> if (config_all_devices.has_key('CONFIG_UEFI_VARS'))
> diff --git a/qapi/machine.json b/qapi/machine.json
> index 038eab281c78..329034035029 100644
> --- a/qapi/machine.json
> +++ b/qapi/machine.json
> @@ -1839,6 +1839,16 @@
> 'returns': 'HumanReadableText',
> 'features': [ 'unstable' ]}
>
> +##
> +# @query-ovmf-log:
> +#
> +# Find firmware memory log buffer in guest memory, return content.
> +#
> +# Since: 10.2
> +##
> +{ 'command': 'query-ovmf-log',
> + 'returns': 'HumanReadableText' }
All other commands returning HumanReadableText are unstable. Does this
one need to be stable? If yes, why?
> +
> ##
> # @dump-skeys:
> #
