Commit Graph

2 Commits

Author SHA1 Message Date
Gerd Hoffmann 645988d9b3 OvmfPkg: add PcdEntryPointOverrideDefaultValue
UefiDriverEntryPointFwCfgOverrideLib will use
PcdEntryPointOverrideDefaultValue to decide what to do in case the
fw_cfg file specified via PcdEntryPointOverrideFwCfgVarName is not
present.  Default is "yes".

This allows to disable drivers by default and only enable them when
requested via fw_cfg.

Also log a message with the config option applied and whenever the
default value or a fw_cfg option was used.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2024-12-06 20:45:29 +00:00
Ard Biesheuvel 477b5b7d55 OvmfPkg: Introduce alternate UefiDriverEntrypoint to inhibit driver load
Add a new library that can be incorporated into any driver built from
source, and which permits loading of the driver to be inhibited based on
the value of a QEMU fw_cfg boolean variable. This will be used in a
subsequent patch to allow dispatch of the IPv4 and IPv6 network protocol
driver to be controlled from the QEMU command line.

This approach is based on the notion that all UEFI and DXE drivers share
a single UefiDriverEntryPoint implementation, which we can easily swap
out at build time with one that will abort execution based on the value
of some QEMU fw_cfg variable.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
2022-09-10 08:23:27 +00:00