When EDK2 OVMF is built with debug, messages are printed to
IO port 0x402. Those messages are not shown in the normal
Qemu emulated serial port. Enabling this option will print
debug messages on the emulated serial port, potentially
mixing messages with UEFI serial console output.
See OVMF README:
https://github.com/tianocore/edk2/blob/master/OvmfPkg/README
This option has been useful to debug problems such as [1], in which the
emulator was hanging at startup without any log. Enabling this option
show the debug message on the console, before hanging:
...
PlatformCpuCountBugCheck: Present=0 Possible=1
PlatformCpuCountBugCheck: Broken CPU hotplug register block found. Update QEMU to version 8+, or
PlatformCpuCountBugCheck: to a stable release with commit dab30fbef389 backported. Refer to
PlatformCpuCountBugCheck: <https://bugzilla.tianocore.org/show_bug.cgi?id=4250>.
...
[1] http://lists.busybox.net/pipermail/buildroot/2023-July/670807.html
Signed-off-by: Julien Olivain <ju.o@free.fr>
Tested-by: Romain Naour <romain.naour@gmail.com>
Reviewed-by: Romain Naour <romain.naour@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
8e9c8e624f