x86/sev-es: Handle NMI State
When running under SEV-ES, the kernel has to tell the hypervisor when to
open the NMI window again after an NMI was injected. This is done with
an NMI-complete message to the hypervisor.
Add code to the kernel's NMI handler to send this message right at the
beginning of do_nmi(). This always allows nesting NMIs.
[ bp: Mark __sev_es_nmi_complete() noinstr:
vmlinux.o: warning: objtool: exc_nmi()+0x17: call to __sev_es_nmi_complete()
leaves .noinstr.text section
While at it, use __pa_nodebug() for the same reason due to
CONFIG_DEBUG_VIRTUAL=y:
vmlinux.o: warning: objtool: __sev_es_nmi_complete()+0xd9: call to __phys_addr()
leaves .noinstr.text section ]
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200907131613.12703-71-joro@8bytes.org