Re: [PATCH v3 57/70] i386/tdx: Wire TDX_REPORT_FATAL_ERROR with GuestPanic facility

Markus Armbruster
2023-12-01T11:11:39Z

Xiaoyao Li <xiaoyao.li@intel.com> writes:

> Integrate TDX's TDX_REPORT_FATAL_ERROR into QEMU GuestPanic facility
>
> Originated-from: Isaku Yamahata <isaku.yamahata@intel.com>
> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
> ---
> Changes from v2:
> - Add docmentation of new type and struct (Daniel)
> - refine the error message handling (Daniel)
> ---
> qapi/run-state.json | 27 ++++++++++++++++++++--
> system/runstate.c | 54 +++++++++++++++++++++++++++++++++++++++++++
> target/i386/kvm/tdx.c | 24 +++++++++++++++++--
> 3 files changed, 101 insertions(+), 4 deletions(-)
>
> diff --git a/qapi/run-state.json b/qapi/run-state.json
> index f216ba54ec4c..e18f62eaef77 100644
> --- a/qapi/run-state.json
> +++ b/qapi/run-state.json
> @@ -496,10 +496,12 @@
> #
> # @s390: s390 guest panic information type (Since: 2.12)
> #
> +# @tdx: tdx guest panic information type (Since: 8.2)
> +#
> # Since: 2.9
> ##
> { 'enum': 'GuestPanicInformationType',
> - 'data': [ 'hyper-v', 's390' ] }
> + 'data': [ 'hyper-v', 's390', 'tdx' ] }
>
> ##
> # @GuestPanicInformation:
> @@ -514,7 +516,8 @@
> 'base': {'type': 'GuestPanicInformationType'},
> 'discriminator': 'type',
> 'data': {'hyper-v': 'GuestPanicInformationHyperV',
> - 's390': 'GuestPanicInformationS390'}}
> + 's390': 'GuestPanicInformationS390',
> + 'tdx' : 'GuestPanicInformationTdx'}}
>
> ##
> # @GuestPanicInformationHyperV:
> @@ -577,6 +580,26 @@
> 'psw-addr': 'uint64',
> 'reason': 'S390CrashReason'}}
>
> +##
> +# @GuestPanicInformationTdx:
> +#
> +# TDX GHCI TDG.VP.VMCALL<ReportFatalError> specific guest panic information

Long line. Suggest

# Guest panic information specific to TDX GHCI
# TDG.VP.VMCALL<ReportFatalError>.

> +#
> +# @error-code: TD-specific error code
> +#
> +# @gpa: 4KB-aligned guest physical address of the page that containing
> +# additional error data

"address of a page" implies the address is page-aligned. 4KB-aligned
feels redundant. What about

# @qpa: guest-physical address of a page that contains additional
# error data.

But in what format is the "additional error data"?

> +#
> +# @message: TD guest provided message string. (It's not so trustable
> +# and cannot be assumed to be well formed because it comes from guest)

guest-provided

For "well-formed" to make sense, we'd need an idea of the form / syntax.

If it's a human-readable error message, we could go with

# @message: Human-readable error message provided by the guest. Not
# to be trusted.

> +#
> +# Since: 8.2
> +##
> +{'struct': 'GuestPanicInformationTdx',
> + 'data': {'error-code': 'uint64',
> + 'gpa': 'uint64',
> + 'message': 'str'}}
> +
> ##
> # @MEMORY_FAILURE:
> # …