diff options
author | Jian J Wang <jian.j.wang@intel.com> | 2017-10-09 21:56:32 +0800 |
---|---|---|
committer | Eric Dong <eric.dong@intel.com> | 2017-10-11 16:39:00 +0800 |
commit | 9189ec20b9e22fe1ec61caefa47a3b3a3cad23a3 (patch) | |
tree | d738689ef454b457b520491957378d600b7cb7a4 /MdeModulePkg/Core/Dxe/Misc | |
parent | f7e077768fe47075130bfa774c88c331d2ad54ff (diff) | |
download | edk2-9189ec20b9e22fe1ec61caefa47a3b3a3cad23a3.tar.gz edk2-9189ec20b9e22fe1ec61caefa47a3b3a3cad23a3.tar.bz2 edk2-9189ec20b9e22fe1ec61caefa47a3b3a3cad23a3.zip |
MdeModulePkg/DxeIpl: Implement NULL pointer detection
NULL pointer detection is done by making use of paging mechanism of CPU.
During page table setup, if enabled, the first 4-K page (0-4095) will be
marked as NOT PRESENT. Any code which unintentionally access memory between
0-4095 will trigger a Page Fault exception which warns users that there's
potential illegal code in BIOS.
This also means that legacy code which has to access memory between 0-4095
should be cautious to temporarily disable this feature before the access
and re-enable it afterwards; or disalbe this feature at all.
Cc: Star Zeng <star.zeng@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Cc: Ayellet Wolman <ayellet.wolman@intel.com>
Suggested-by: Ayellet Wolman <ayellet.wolman@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Diffstat (limited to 'MdeModulePkg/Core/Dxe/Misc')
0 files changed, 0 insertions, 0 deletions