Jiading:
HOB is created in volatile memory (cache or physical memory). And, HOB is
re-created for every boot (normal boot, S3 boot). When the first call
GetVariable, gEfiVariableIndexTableGuid guid hob should not exist. If this guid
hob exits, it should be created by other module. Please check.
Thanks
Liming
发件人: Jiading Zhang <jdzh...@kunluntech.com.cn>
发送时间: 2022年10月10日 16:36
收件人: gaoliming <gaolim...@byosoft.com.cn>; devel@edk2.groups.io
主题: Re: [edk2-devel] 回复: [edk2-devel] 回复: [edk2-devel] [PATCH] MdeModulePkg
VariablePei: Add Variable state check when find variable in IndexTable.
Hi liming:
I checked the code, and found the root cause of the issue.
As the following code in edk2, in my code, after the first time to read
the variable in PEI phase, it cached the variable store info IndexTable into
a Hob in a special non-volatile memory, but after the code running in dxe
phase, the variable was changed. And after a warm reboot, maybe call s3 sleep
is more exactly, when read the variable, it first get the IndexTable from the
Hob but not build the IndexTable again, so it read the deleted variable if
hasn't the condition check. This is really a special case.
GuidHob = GetFirstGuidHob (&gEfiVariableIndexTableGuid);
if (GuidHob != NULL) {
StoreInfo->IndexTable = GET_GUID_HOB_DATA (GuidHob);
} else {
//
// If it's the first time to access variable region in flash, create
a guid hob to record
// VAR_ADDED type variable info.
// Note that as the resource of PEI phase is limited, only store the
limited number of
// VAR_ADDED type variables to reduce access time.
//
StoreInfo->IndexTable = (VARIABLE_INDEX_TABLE *) BuildGuidHob
(&gEfiVariableIndexTableGuid, sizeof (VARIABLE_INDEX_TABLE));
StoreInfo->IndexTable->Length = 0;
StoreInfo->IndexTable->StartPtr = GetStartPointer
(VariableStoreHeader);
StoreInfo->IndexTable->EndPtr = GetEndPointer
(VariableStoreHeader);
StoreInfo->IndexTable->GoneThrough = 0;
}
On Mon, Oct 10, 2022 at 09:39 AM, gaoliming wrote:
Jiading:
Please check why NV variable data is required to be changed in PEI phase.
This will be helpful for this issue.
Thanks
Liming
发件人: Jiading Zhang <jdzh...@kunluntech.com.cn
<mailto:jdzh...@kunluntech.com.cn> >
发送时间: 2022年10月10日 8:35
收件人: gaoliming <gaolim...@byosoft.com.cn <mailto:gaolim...@byosoft.com.cn> >;
devel@edk2.groups.io <mailto:devel@edk2.groups.io>
主题: Re: [edk2-devel] 回复: [edk2-devel] [PATCH] MdeModulePkg VariablePei: Add
Variable state check when find variable in IndexTable.
Hi liming:
Yes, NV Variable Data is not changed in PEI phase in normal case. This issue
was found when we did a special coding, and when found variable in the
IndexTable, it found the variable before the last changed if didn't add the
following condition:
"if ((VariableHeader->State == VAR_ADDED) || (VariableHeader->State ==
(VAR_IN_DELETED_TRANSITION & VAR_ADDED)))"
Maybe our specail coding had some defect，and caused this issue.
On Fri, Sep 30, 2022 at 10:46 AM, gaoliming wrote:
Jiading:
Hob Variable Store Info IndexTable is NULL. So, this logic doesn’t work for
HOB variable store. NV Variable Store Info has IndexTable. When its IndexTable
is initialized, its IndexTable will only record the variable with VAR_ADDED
attribute. Because NV Variable Data is not changed in PEI phase, this check is
not required by NV variable.
Thanks
Liming
发件人: devel@edk2.groups.io <mailto:devel@edk2.groups.io> <devel@edk2.groups.io
<mailto:devel@edk2.groups.io> > 代表 Jiading Zhang
发送时间: 2022年9月28日 11:05
收件人: devel@edk2.groups.io <mailto:devel@edk2.groups.io>
主题: [edk2-devel] [PATCH] MdeModulePkg VariablePei: Add Variable state check
when find variable in IndexTable.
When read a variable in PEI, it will find it first in the HOB, then find in
variable store. When find in variable store, it will check the variable state,
but find in HOB, it doesn't check the state, so if the variable was changed, it
will find the obsolete variable in the HOB.
Signed-off-by: jdzhang <jdzh...@kunluntech.com.cn
<mailto:jdzh...@kunluntech.com.cn> >
---
MdeModulePkg/Universal/Variable/Pei/Variable.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/MdeModulePkg/Universal/Variable/Pei/Variable.c
b/MdeModulePkg/Universal/Variable/Pei/Variable.c
index 26a4c73b45..dffbd8cdb1 100644
--- a/MdeModulePkg/Universal/Variable/Pei/Variable.c
+++ b/MdeModulePkg/Universal/Variable/Pei/Variable.c
@@ -866,11 +866,13 @@ FindVariableEx (
Offset += IndexTable->Index[Index];
MaxIndex = (VARIABLE_HEADER *)((UINT8 *)IndexTable->StartPtr + Offset);
GetVariableHeader (StoreInfo, MaxIndex, &VariableHeader);
- if (CompareWithValidVariable (StoreInfo, MaxIndex, VariableHeader,
VariableName, VendorGuid, PtrTrack) == EFI_SUCCESS) {
- if (VariableHeader->State == (VAR_IN_DELETED_TRANSITION & VAR_ADDED)) {
- InDeletedVariable = PtrTrack->CurrPtr;
- } else {
- return EFI_SUCCESS;
+ if ((VariableHeader->State == VAR_ADDED) || (VariableHeader->State ==
(VAR_IN_DELETED_TRANSITION & VAR_ADDED))) {
+ if (CompareWithValidVariable (StoreInfo, MaxIndex, VariableHeader,
VariableName, VendorGuid, PtrTrack) == EFI_SUCCESS) {
+ if (VariableHeader->State == (VAR_IN_DELETED_TRANSITION &
VAR_ADDED)) {
+ InDeletedVariable = PtrTrack->CurrPtr;
+ } else {
+ return EFI_SUCCESS;
+ }
}
}
}
--
2.20.1.windows.1
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