CVE-2021-47228 x86/ioremap: Map EFI-reserved memory as encrypted for SEV

In the Linux kernel, the following vulnerability has been resolved: x86/ioremap: Map EFI-reserved memory as encrypted for SEV Some drivers require memory that is marked as EFI boot services data. In order for this memory to not be re-used by the kernel after ExitBootServices, efimemreserve is use...

CVE-2021-47228

CVE-2021-47228 affects the Linux kernel x86/ioremap code. The issue arises when EFI boot services memory is preserved with efi_mem_reserve() and marked EFI_MEMORY_RUNTIME; under SEV, such memory must be mapped encrypted, otherwise the kernel may crash during boot. The public docs indicate a fix t...