PiSmmCpuDxeSmm consumes SmmAttributesTable and setup page table:
1) Code region is marked as read-only and Data region is non-executable,
if the PE image is 4K aligned.
2) Important data structure is set to RO, such as GDT/IDT.
3) SmmSaveState is set to non-executable,
and SmmEntrypoint is set to read-only.
4) If static page is supported, page table is read-only.
We use page table to protect other components, and itself.
If we use dynamic paging, we can still provide *partial* protection.
And hope page table is not modified by other components.
The XD enabling code is moved to SmiEntry to let NX take effect.
Cc: Jeff Fan <jeff.fan@intel.com>
Cc: Feng Tian <feng.tian@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jiewen Yao <jiewen.yao@intel.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jeff Fan <jeff.fan@intel.com>
Reviewed-by: Michael D Kinney <michael.d.kinney@intel.com>
So that we can use write-protection for code later.
It is REPOST.
It includes suggestion from Michael Kinney <michael.d.kinney@intel.com>:
- "For IA32 assembly, can we combine into a single OR instruction that
sets both page enable and WP?"
- "For X64, does it make sense to use single OR instruction instead of 2
BTS instructions as well?"
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: "Yao, Jiewen" <jiewen.yao@intel.com>
Suggested-by: Michael Kinney <michael.d.kinney@intel.com>
Reviewed-by: Michael Kinney <michael.d.kinney@intel.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Cc: "Fan, Jeff" <jeff.fan@intel.com>
Cc: "Kinney, Michael D" <michael.d.kinney@intel.com>
Cc: "Laszlo Ersek" <lersek@redhat.com>
Cc: "Paolo Bonzini" <pbonzini@redhat.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@19068 6f19259b-4bc3-4df7-8a09-765794883524
Always set RW+P bit for page table by default.
So that we can use write-protection for code later.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: "Yao, Jiewen" <jiewen.yao@intel.com>
Reviewed-by: "Kinney, Michael D" <michael.d.kinney@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18960 6f19259b-4bc3-4df7-8a09-765794883524
SmmDebug feature is implemented in ASM, which is not easy to maintain.
So we move it to C function.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: "Yao, Jiewen" <jiewen.yao@intel.com>
Reviewed-by: "Kinney, Michael D" <michael.d.kinney@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18946 6f19259b-4bc3-4df7-8a09-765794883524
Add module that initializes a CPU for the SMM environment and
installs the first level SMI handler. This module along with the
SMM IPL and SMM Core provide the services required for
DXE_SMM_DRIVERS to register hardware and software SMI handlers.
CPU specific features are abstracted through the SmmCpuFeaturesLib
Platform specific features are abstracted through the
SmmCpuPlatformHookLib
Several PCDs are added to enable/disable features and configure
settings for the PiSmmCpuDxeSmm module
[jeff.fan@intel.com: Fix code style issues reported by ECC]
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Michael Kinney <michael.d.kinney@intel.com>
Reviewed-by: Jeff Fan <jeff.fan@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18646 6f19259b-4bc3-4df7-8a09-765794883524