S3RestoreConfig2() can optionally stack-switch to the SMM S3 Resume Entry
Point and ask it to transfer to S3ResumeExecuteBootScript().
Similarly, S3ResumeExecuteBootScript() stack-switches explicitly to the
boot script executor, and asks it to transfer to S3ResumeBootOs().
Currently the stack pointers specified for the SMM S3 Resume Entry Point
and the boot script executor to use for returning are derived from
addresses of the first local variables in S3RestoreConfig2() and
S3ResumeExecuteBootScript(), respectively.
Since (theoretically) the stack grows down as local variables are defined
and functions are called, the idea is presumably to allow the respective
callee to overwrite the caller's local variables. (The callees in
question can never return normally, only by explicit stack switching.)
Taking the address of "Status" is less portable than optimal however.
Compilers are free to juggle local variables at build time as they
please, including order and alignment on the stack. For example, when the
code is built for 64-bit PEI with gcc-4.8.2, the address of "Status"
trips up the alignment assertion in SwitchStack().
Let's align the address of "Status" down to CPU_STACK_ALIGNMENT
explicitly. If a compiler ensures such alignment and places "Status" at
the highest address automatically, then this change has no effect.
Otherwise, we'll prepare ReturnStackPointer values that (a) are correctly
aligned, (b) preserve the same amount or more (but never less) from the
caller's local variables than before, which should be safe.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed by: Jiewen Yao <Jiewen.Yao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@14977 6f19259b-4bc3-4df7-8a09-765794883524
SMM S3 resume may change memory cache type for flash memory range and thus RestoreS3PageTables() in which loops are executed to create page table would have negative performance impact on S3 resume. Move the call to RestoreS3PageTables() earlier before SMM S3 resume can avoid this issue.
Signed-off-by: Sun Rui <rui.sun@intel.com>
Reviewed-by: Yao Jiewen <jiewen.yao@intel.com>
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13231 6f19259b-4bc3-4df7-8a09-765794883524
2. Updated BootScriptSaveOnS3SaveStateThunk restore IA32 IDT table before transferring to protected mode.
It could support exception handler in 32-bit Framework Boot Script code.
Signed-off-by: vanjeff
Reviewed-by: jyao1
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13099 6f19259b-4bc3-4df7-8a09-765794883524
Laszlo Ersek
Liming Gao
li-elvin
vanjeff
lzeng14
jyao1
rsun3
jljusten