b888c57a05
BZ#1116: https://bugzilla.tianocore.org/show_bug.cgi?id=1116 The usage of following PCDs described in MdeModulePkg.dec don't match the implementation exactly. This patch updates related description in both .dec and .uni files to avoid confusion in platform configuration. PcdSetNxForStack PcdImageProtectionPolicy PcdDxeNxMemoryProtectionPolicy The main change is at the statement on how to handle the FALSE or 0 setting value in those PCDs. Current statement says the implementation should unset or disable related features but in fact the related code just do nothing (leave it to AS-IS). That means the result might be disabled, or might be not. It depends on other features or platform policy. For example, if one don't want to enforce NX onto stack memory, he/she needs to set PcdSetNxForStack to FALSE as well as to clear BIT4 of PcdDxeNxMemoryProtectionPolicy. Cc: Star Zeng <star.zeng@intel.com> Cc: Laszlo Ersek <lersek@redhat.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Ruiyu Ni <ruiyu.ni@intel.com> Cc: Jiewen Yao <jiewen.yao@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: Laszlo Ersek <lersek@redhat.com>