BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2198
Add base support to handle #VC exceptions. Update the common exception
handlers to invoke the VmgExitHandleVc () function of the VmgExitLib
library when a #VC is encountered. A non-zero return code will propagate
to the targeted exception handler.
Under SEV-ES, a DR7 read or write intercept generates a #VC exception.
To avoid exception recursion, a #VC exception will not try to read and
push the actual debug registers into the EFI_SYSTEM_CONTEXT_X64 struct
and instead push zeroes. The #VC exception handler does not make use of
the debug registers from the saved context and the exception processing
exit code does not attempt to restore the debug register values.
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2340
Commit 2db0ccc2d7 ("UefiCpuPkg: Update CpuExceptionHandlerLib pass
XCODE5 tool chain") introduced binary patching into the exception handling
support. CPU exception handling is allowed during SEC and this results in
binary patching of flash, which should not be done.
Separate the changes from commit 2db0ccc2d7 into an XCODE5 toolchain
specific file, Xcode5ExceptionHandlerAsm.nasm, and create a new SEC INF
file for the XCODE5 version of CpuExceptionHandlerLib.
Since binary patching is allowed when running outside of flash, switch
the Dxe, Pei and Smm versions of the CpuExceptionHandlerLib over to use
the Xcode5ExceptionHandlerAsm.nasm file to retain current functionality.
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Liming Gao <liming.gao@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <9075570487616c731033a5738f6a444a15d71b74.1588856809.git.thomas.lendacky@amd.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Tom Lendacky