md_size will have been narrowed if we have >= 4GB worth of pages in a
soft-reserved region.
Signed-off-by: Andrew Bresticker <abrestic@rivosinc.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Only the arch_efi_call_virt() macro that some architectures override
needs to be a macro, given that it is variadic and encapsulates calls
via function pointers that have different prototypes.
The associated setup and teardown code are not special in this regard,
and don't need to be instantiated at each call site. So turn them into
ordinary C functions and move them out of line.
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
The generic EFI stub can be instructed to avoid SetVirtualAddressMap(),
and simply run with the firmware's 1:1 mapping. In this case, it
populates the virtual address fields of the runtime regions in the
memory map with the physical address of each region, so that the mapping
code has to be none the wiser. Only if SetVirtualAddressMap() fails, the
virtual addresses are wiped and the kernel code knows that the regions
cannot be mapped.
However, wiping amounts to setting it to zero, and if a runtime region
happens to live at physical address 0, its valid 1:1 mapped virtual
address could be mistaken for a wiped field, resulting on loss of access
to the EFI services at runtime.
So let's only assume that VA == 0 means 'no runtime services' if the
region in question does not live at PA 0x0.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>