BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=1191
Before commit e21e355e2c, jmp _SmiHandler
is commented. And below code, ASM_PFX(CpuSmmDebugEntry) is moved into rax,
then call it. But, this code doesn't work in XCODE5 tool chain. Because XCODE5
doesn't generated the absolute address in the EFI image. So, rax stores the
relative address. Once this logic is moved to another place, it will not work.
; jmp _SmiHandler ; instruction is not needed
...
mov rax, ASM_PFX(CpuSmmDebugEntry)
call rax
Commit e21e355e2c is to support XCODE5.
One tricky way is selected to fix it. Although SmiEntry logic is copied to
another place and run, but here jmp _SmiHandler is enabled to jmp the original
code place, then call ASM_PFX(CpuSmmDebugEntry) with the relative address.
mov rax, strict qword 0 ; mov rax, _SmiHandler
_SmiHandlerAbsAddr:
jmp rax
...
call ASM_PFX(CpuSmmDebugEntry)
Now, BZ 1191 raises the issue that SmiHandler should run in the copied address,
can't run in the common address. So, jmp _SmiHandler is required to be removed,
the code is kept to run in copied address. And, the relative address is
requried to be fixed up to the absolute address. The necessary changes should
not affect the behavior of platforms that already consume PiSmmCpuDxeSmm.
OVMF SMM boot to shell with VS2017, GCC5 and XCODE5 tool chain has been verified.
...
mov rax, strict qword 0 ; call ASM_PFX(CpuSmmDebugEntry)
CpuSmmDebugEntryAbsAddr:
call rax
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Liming Gao <liming.gao@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
a364928195