From d2f7cbe7b26a74dbbbf8f325b2a6fd01bc34032c Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Thu, 31 Oct 2013 17:25:08 +0100 Subject: x86/efi: Runtime services virtual mapping We map the EFI regions needed for runtime services non-contiguously, with preserved alignment on virtual addresses starting from -4G down for a total max space of 64G. This way, we provide for stable runtime services addresses across kernels so that a kexec'd kernel can still use them. Thus, they're mapped in a separate pagetable so that we don't pollute the kernel namespace. Add an efi= kernel command line parameter for passing miscellaneous options and chicken bits from the command line. While at it, add a chicken bit called "efi=old_map" which can be used as a fallback to the old runtime services mapping method in case there's some b0rkage with a particular EFI implementation (haha, it is hard to hold up the sarcasm here...). Also, add the UEFI RT VA space to Documentation/x86/x86_64/mm.txt. Signed-off-by: Borislav Petkov Signed-off-by: Matt Fleming --- include/linux/efi.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/efi.h') diff --git a/include/linux/efi.h b/include/linux/efi.h index bc5687d0f315..6c0ca528300c 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -653,6 +653,7 @@ extern int __init efi_setup_pcdp_console(char *); #define EFI_RUNTIME_SERVICES 3 /* Can we use runtime services? */ #define EFI_MEMMAP 4 /* Can we use EFI memory map? */ #define EFI_64BIT 5 /* Is the firmware 64-bit? */ +#define EFI_ARCH_1 6 /* First arch-specific bit */ #ifdef CONFIG_EFI # ifdef CONFIG_X86 -- cgit v1.2.3-59-g8ed1b