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author | Tom Lendacky <thomas.lendacky@amd.com> | 2023-07-14 15:28:26 -0500 |
---|---|---|
committer | mergify[bot] <37929162+mergify[bot]@users.noreply.github.com> | 2023-07-14 22:52:58 +0000 |
commit | e674096accc8e57cd0dd84679905e1222423251e (patch) | |
tree | d80b2c4dd81054c5eba0fc6ee64b06736f85039b | |
parent | ff3382a51ca726a90f49623a2b2d2e8ad8459ce2 (diff) | |
download | edk2-e674096accc8e57cd0dd84679905e1222423251e.zip edk2-e674096accc8e57cd0dd84679905e1222423251e.tar.gz edk2-e674096accc8e57cd0dd84679905e1222423251e.tar.bz2 |
OvmfPkg/ResetVector: Fix assembler bit test flag check
Commit 63c50d3ff2854a76432b752af4f2a76f33ff1974 changed the check that is
used to determine if SEV-ES is active. Originally, a CMP instruction with
a supporting JZ instruction was used for the check. It was changed to use
the BT instruction but not JZ instruction. The result of a BT instruction
changes the the carry flag (CF) and not the zero flag (ZF). As a result,
the wrong condition is being checked. Update the JZ to a JNC to properly
detect if SEV-ES is active.
Fixes: 63c50d3ff285 ("OvmfPkg/ResetVector: cache the SEV status MSR...")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
-rw-r--r-- | OvmfPkg/ResetVector/Ia32/Flat32ToFlat64.asm | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/OvmfPkg/ResetVector/Ia32/Flat32ToFlat64.asm b/OvmfPkg/ResetVector/Ia32/Flat32ToFlat64.asm index c5c683e..429a58c 100644 --- a/OvmfPkg/ResetVector/Ia32/Flat32ToFlat64.asm +++ b/OvmfPkg/ResetVector/Ia32/Flat32ToFlat64.asm @@ -44,7 +44,7 @@ Transition32FlatTo64Flat: mov ecx, 1
bt [SEV_ES_WORK_AREA_STATUS_MSR], ecx
- jz EnablePaging
+ jnc EnablePaging
;
; SEV-ES is active, perform a quick sanity check against the reported
|