> On Mar 31, 2015, at 6:25 PM, Yao, Jiewen <jiewen....@intel.com> wrote:
>
> Yes. It seems a bug.
> We should initialize it.
Thanks!
The other thing that looked strange to me was: mS3BootScriptTablePtr and
mS3BootScriptTableSmmPtr of type SCRIPT_TABLE_PRIVATE_DATA.
//
// The boot script private data.
//
typedef struct {
UINT8 *TableBase;
UINT32 TableLength; // Record the actual memory length
UINT16 TableMemoryPageNumber; // Record the page number
Allocated for the table
BOOLEAN AtRuntime; // Record if current state is
after SmmReadyToLock
BOOLEAN InSmm; // Record if this library is in
SMM.
} SCRIPT_TABLE_PRIVATE_DATA;
Given mS3BootScriptTablePtr is a library global there are N copies of them in
the system. So TableLength and TableMemoryPageNumber can get out of sync with
reality. I don’t see the point in tracking the data in N places. Seems like all
the instances of SCRIPT_TABLE_PRIVATE_DATA.TableBase point to
EFI_BOOT_SCRIPT_TABLE_HEADER, so that is the only length that means anything.
It probably generally seems to work as a driver does writes in batches. But if
a driver did a batch of writes, and then did work in an event. Its cached
SCRIPT_TABLE_PRIVATE_DATA would be out of data with regards to TableLength and
TableMemoryPageNumber.
It looks like a bad value in mS3BootScriptTablePtr could end up truncating the
table. It could be that the later code has a larger value and it runs last? So
maybe it is a race, or we are just getting lucky? Or maybe there is some
syncing back from EFI_BOOT_SCRIPT_TABLE_HEADER that I missed in the code.
Thanks,
Andrew Fish
PS I’ve not seen any bad S3 data. I’m writing a debugger script to dump out the
tables, so I was poking around in memory to debug the script and noticed this
issue.
(lldb) p *mS3BootScriptTablePtr
(SCRIPT_TABLE_PRIVATE_DATA) $120 = {
TableBase = 0x000000007afbe000 "?"
TableLength = 0x000003d1
TableMemoryPageNumber = 0x0004
AtRuntime = true
InSmm = false
}
(lldb) p *(EFI_BOOT_SCRIPT_TABLE_HEADER *)0x000000007afbe000
(EFI_BOOT_SCRIPT_TABLE_HEADER) $121 = {
OpCode = 0x00aa
Length = 0x0d
Version = 0xafaf
TableLength = 0x000005c4
Reserved = ([0] = 0xafaf, [1] = 0xafaf)
}
The last instance of mS3BootScriptTablePtr is this one:
(lldb) p *(SCRIPT_TABLE_PRIVATE_DATA *)0x7b3efa90
(SCRIPT_TABLE_PRIVATE_DATA) $122 = {
TableBase = 0x000000007afbe000 "?"
TableLength = 0x000005c1
TableMemoryPageNumber = 0x0004
AtRuntime = true
InSmm = true
}
>
> Thank you
> Yao Jiewen
>
> -----Original Message-----
> From: Andrew Fish [mailto:af...@apple.com]
> Sent: Wednesday, April 01, 2015 6:32 AM
> To: edk2-devel@lists.sourceforge.net
> Subject: [edk2] MdeModulePkg Maintainer: The PiDxeS3BootScriptLib does not
> seem to set EFI_BOOT_SCRIPT_TABLE_HEADER.Version
>
> I don’t see any code in the PiDxeS3BootScriptLib that sets a value to
> EFI_BOOT_SCRIPT_TABLE_HEADER.Version. The data is allocated via
> gBS->AllocatePages, and on the system I looked at the Version was set to
> 0xafaf.
>
> It seems like the driver should initialize this member to a known value?
>
> Thanks,
>
> Andrew Fish
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