summaryrefslogtreecommitdiffstats
path: root/drivers/firmware/efi/memattr.c
AgeCommit message (Collapse)Author
2017-02-01x86/efi: Add support for EFI_MEMORY_ATTRIBUTES_TABLESai Praneeth
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 <sai.praneeth.prakhya@intel.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Lee, Chun-Yi <jlee@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: Ricardo Neri <ricardo.neri@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1485868902-20401-6-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-01efi: Introduce the EFI_MEM_ATTR bit and set it from the memory attributes tableSai Praneeth
UEFI v2.6 introduces a configuration table called EFI_MEMORY_ATTRIBUTES_TABLE which provides additional information about EFI runtime regions. Currently this table describes memory protections that may be applied to the EFI Runtime code and data regions by the kernel. Allocate a EFI_XXX bit to keep track of whether this feature is published by firmware or not. Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Lee, Chun-Yi <jlee@suse.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: Ricardo Neri <ricardo.neri@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1485868902-20401-5-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-28efi: Implement generic support for the Memory Attributes tableArd Biesheuvel
This implements shared support for discovering the presence of the Memory Attributes table, and for parsing and validating its contents. The table is validated against the construction rules in the UEFI spec. Since this is a new table, it makes sense to complain if we encounter a table that does not follow those rules. The parsing and validation routine takes a callback that can be specified per architecture, that gets passed each unique validated region, with the virtual address retrieved from the ordinary memory map. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> [ Trim pr_*() strings to 80 cols and use EFI consistently. ] Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-14-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>