Hello Kyösti Mälkki, Aaron Durbin, Arthur Heymans, Stefan Reinauer, Paul Menzel, build bot (Jenkins), Raul Rangel, Patrick Georgi, ron minnich, Rudolf Marek, Lee Leahy, David Hendricks, Martin Roth,
I'd like you to reexamine a change. Please visit
https://review.coreboot.org/c/coreboot/+/35681
to look at the new patch set (#7).
Change subject: cpu/x86/smm: Add support for long mode ......................................................................
cpu/x86/smm: Add support for long mode
Enable long mode in SMM handler. x86_32 isn't affected from this change.
As the rsm instruction used to leave SMM doesn't restore MSR registers, drop back to protected mode after running the smi_handler and restore IA32_EFER MSR (which enables long mode support) to previous value.
For now the same page tables as for all other stages are used. If there's enough space in SMM, one could install additional page tables in SMRAM to enable additional features.
Tested on Qemu Q35. Needs tests on real hardware.
Change-Id: I8bba4af4688c723fc079ae905dac95f57ea956f8 Signed-off-by: Patrick Rudolph siro@das-labor.org --- M Documentation/arch/x86/index.md A src/cpu/x86/64bit/exit32.inc M src/cpu/x86/smm/smmhandler.S 3 files changed, 144 insertions(+), 1 deletion(-)
git pull ssh://review.coreboot.org:29418/coreboot refs/changes/81/35681/7