PEI variable implementation checks only the variable header signature for validity. This does not seem robust if system crash occurred during previous Reclaim() operation. If the crash occurred while FTW was rewriting the variable FV, the signature could be valid even though the rest of the FV isn't valid.
Solution: Add a FaultTolerantWritePei driver to check and provide the FTW last write status, then PEI variable and early phase(before FTW protocol ready) of DXE variable can check the status and determine if all or partial variable data has been backed up in spare block, and then use the backed up data.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@14454 6f19259b-4bc3-4df7-8a09-765794883524
PcdFlashNvStorageFtwWorkingBase and PcdFlashNvStorageFtwSpareBase are
now updated each time an FVB instance is installed. This allows the
PCDs to be set at runtime at any time before the FVB is installed.
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@9312 6f19259b-4bc3-4df7-8a09-765794883524