Re: [PATCH v3] hw/uefi: add "info firmware-log" + "query-firmware-log" monitor commands

["Daniel P. Berrangé" <berrange@redhat.com>]

On Mon, Oct 13, 2025 at 09:11:47PM +0200, Philippe Mathieu-Daudé wrote:
> On 10/10/25 09:10, Gerd Hoffmann wrote:
> > 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 <kraxel@redhat.com>
> > ---
> >   include/monitor/hmp.h      |   1 +
> >   hw/uefi/ovmf-log.c         | 265 +++++++++++++++++++++++++++++++++++++
> >   tests/qtest/qmp-cmd-test.c |   2 +
> >   hmp-commands-info.hx       |  14 ++
> >   hw/uefi/meson.build        |   2 +-
> >   qapi/machine.json          |  23 ++++
> >   6 files changed, 306 insertions(+), 1 deletion(-)
> >   create mode 100644 hw/uefi/ovmf-log.c
> 
> At a glance, why not "info ovmf-log" and "query-ovmf-log"?

I would say that conceptually any firmware could expose logs in memory
for QEMU to access. So even if we only have an impl for OVMF today,
it makes sense to leave the door open for impls for other firmware
types.

With regards,
Daniel
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