path: root/arch/x86/platform/efi/efi_32.c
diff options
authorBorislav Petkov <bp@suse.de>2013-10-31 17:25:08 +0100
committerMatt Fleming <matt.fleming@intel.com>2013-11-02 11:09:36 +0000
commitd2f7cbe7b26a74dbbbf8f325b2a6fd01bc34032c (patch)
tree69d2c1f92120fa532c77cf8634418b7622d55692 /arch/x86/platform/efi/efi_32.c
parent82f0712ca0f947170e785300b5c39d9c25e2f6ff (diff)
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 <bp@suse.de> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Diffstat (limited to 'arch/x86/platform/efi/efi_32.c')
1 files changed, 8 insertions, 1 deletions
diff --git a/arch/x86/platform/efi/efi_32.c b/arch/x86/platform/efi/efi_32.c
index 40e446941dd7..e94557cf5487 100644
--- a/arch/x86/platform/efi/efi_32.c
+++ b/arch/x86/platform/efi/efi_32.c
@@ -37,9 +37,16 @@
* claim EFI runtime service handler exclusively and to duplicate a memory in
* low memory space say 0 - 3G.
static unsigned long efi_rt_eflags;
+void efi_sync_low_kernel_mappings(void) {}
+void efi_setup_page_tables(void) {}
+void __init efi_map_region(efi_memory_desc_t *md)
+ old_map_region(md);
void efi_call_phys_prelog(void)
struct desc_ptr gdt_descr;

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