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author | Tom Lendacky <thomas.lendacky@amd.com> | 2021-01-07 12:48:14 -0600 |
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committer | mergify[bot] <37929162+mergify[bot]@users.noreply.github.com> | 2021-01-07 19:34:39 +0000 |
commit | bd0c1c8e225b1274fc7e3f154811af40619e3f04 (patch) | |
tree | a83cc103896ecc1d115f7b0be845b1452e5c16a6 /OvmfPkg | |
parent | 7cb96c47a94ea310b151c36380ea8266d21aa12a (diff) | |
download | edk2-bd0c1c8e225b1274fc7e3f154811af40619e3f04.zip edk2-bd0c1c8e225b1274fc7e3f154811af40619e3f04.tar.gz edk2-bd0c1c8e225b1274fc7e3f154811af40619e3f04.tar.bz2 |
OvmfPkg/ResetVector: Perform a simple SEV-ES sanity check
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3108
If a hypervisor incorrectly reports through CPUID that SEV-ES is not
active, ensure that a #VC exception was not taken. If it is found that
a #VC was taken, then the code enters a HLT loop.
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <afa2030b95b852313b13982df82d472187e59b92.1610045305.git.thomas.lendacky@amd.com>
Diffstat (limited to 'OvmfPkg')
-rw-r--r-- | OvmfPkg/ResetVector/Ia32/PageTables64.asm | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/OvmfPkg/ResetVector/Ia32/PageTables64.asm b/OvmfPkg/ResetVector/Ia32/PageTables64.asm index ccc95ad..a1771df 100644 --- a/OvmfPkg/ResetVector/Ia32/PageTables64.asm +++ b/OvmfPkg/ResetVector/Ia32/PageTables64.asm @@ -154,6 +154,22 @@ SevEncBitLowHlt: jmp SevEncBitLowHlt
NoSev:
+ ;
+ ; Perform an SEV-ES sanity check by seeing if a #VC exception occurred.
+ ;
+ cmp byte[SEV_ES_WORK_AREA], 0
+ jz NoSevPass
+
+ ;
+ ; A #VC was received, yet CPUID indicates no SEV-ES support, something
+ ; isn't right.
+ ;
+NoSevEsVcHlt:
+ cli
+ hlt
+ jmp NoSevEsVcHlt
+
+NoSevPass:
xor eax, eax
SevExit:
|