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| author | Tom Lendacky <thomas.lendacky@amd.com> | 2024-03-08 07:30:56 -0800 |
|---|---|---|
| committer | mergify[bot] <37929162+mergify[bot]@users.noreply.github.com> | 2024-04-17 18:30:03 +0000 |
| commit | f40c1f2a30fc58835cb28efc73c40d52c29363fd (patch) | |
| tree | 589ef3f2855005df358aea29a0cf130d3195422b | |
| parent | 5fe9db0f8220aa10ecb8c15f3188e024982111a7 (diff) | |
| download | edk2-f40c1f2a30fc58835cb28efc73c40d52c29363fd.tar.gz | |
MdePkg: Avoid hardcoded value for number of Page State Change entries
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=4654
The SNP_PAGE_STATE_MAX_ENTRY is based on the number of entries that can
fit in the GHCB shared buffer. As a result, the SNP_PAGE_STATE_CHANGE_INFO
structure maps the full GHCB shared buffer based on the shared buffer size
being 2032 bytes.
Instead of using a hardcoded value for SNP_PAGE_STATE_MAX_ENTRY, use a
build calculated value. Since the SNP_PAGE_STATE_CHANGE_INFO is used as a
mapping, eliminate the hardcoded array size so that the structure can be
used based on any size buffer.
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Zhiguang Liu <zhiguang.liu@intel.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
| -rw-r--r-- | MdePkg/Include/Register/Amd/Ghcb.h | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/MdePkg/Include/Register/Amd/Ghcb.h b/MdePkg/Include/Register/Amd/Ghcb.h index bd7bf986d0..ae1486b526 100644 --- a/MdePkg/Include/Register/Amd/Ghcb.h +++ b/MdePkg/Include/Register/Amd/Ghcb.h @@ -197,13 +197,14 @@ typedef struct { UINT32 Reserved;
} SNP_PAGE_STATE_HEADER;
-#define SNP_PAGE_STATE_MAX_ENTRY 253
-
typedef struct {
SNP_PAGE_STATE_HEADER Header;
- SNP_PAGE_STATE_ENTRY Entry[SNP_PAGE_STATE_MAX_ENTRY];
+ SNP_PAGE_STATE_ENTRY Entry[];
} SNP_PAGE_STATE_CHANGE_INFO;
+#define SNP_PAGE_STATE_MAX_ENTRY \
+ ((sizeof (((GHCB *)0)->SharedBuffer) - sizeof (SNP_PAGE_STATE_HEADER)) / sizeof (SNP_PAGE_STATE_ENTRY))
+
//
// Get APIC IDs
//
|