A-Team_Digital_Solutions/android_kernel_motorola_sm6375
Watch
2
0
Fork
You've already forked android_kernel_motorola_sm6375
 0
mirror of https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git synced 2026-10-28 10:41:38 -04:00
Code Issues Projects Releases Packages Wiki Activity

x86/efi: Add support for EFI_MEMORY_ATTRIBUTES_TABLE

Browse source 
UEFI v2.6 introduces EFI_MEMORY_ATTRIBUTES_TABLE which describes memory
protections that may be applied to the EFI Runtime code and data regions by
the kernel. This enables the kernel to map these regions more strictly thereby
increasing security.

Presently, the only valid bits for the attribute field of a memory descriptor
are EFI_MEMORY_RO and EFI_MEMORY_XP, hence use these bits to update the
mappings in efi_pgd.

The UEFI specification recommends to use this feature instead of
EFI_PROPERTIES_TABLE and hence while updating EFI mappings we first
check for EFI_MEMORY_ATTRIBUTES_TABLE and if it's present we update
the mappings according to this table and hence disregarding
EFI_PROPERTIES_TABLE even if it's published by the firmware. We consider
EFI_PROPERTIES_TABLE only when EFI_MEMORY_ATTRIBUTES_TABLE is absent.

Signed-off-by: Sai Praneeth Prakhya <[email protected]>
Signed-off-by: Matt Fleming <[email protected]>
Signed-off-by: Ard Biesheuvel <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Fenghua Yu <[email protected]>
Cc: Lee, Chun-Yi <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ravi Shankar <[email protected]>
Cc: Ricardo Neri <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
This commit is contained in:
Sai Praneeth 2017-01-31 13:21:37 +00:00 • committed by Ingo Molnar
commit 18141e89a7
2 changed files with 58 additions and 11 deletions
Download patch file Download diff file Expand all files Collapse all files

5
drivers/firmware/efi/memattr.c
View file

@ -175,8 +175,11 @@ int __init efi_memattr_apply_permissions(struct mm_struct *mm,
md.phys_addr + size - 1,
efi_md_typeattr_format(buf, sizeof(buf), &md));
if (valid)
if (valid) {
ret = fn(mm, &md);
if (ret)
pr_err("Error updating mappings, skipping subsequent md's\n");
}
}
memunmap(tbl);
return ret;