Bug 5328

Summary:	Access to FieldObject element of Package causes exception
Product:	ACPI	Reporter:	Valery A Podrezov (Valery.A.Podrezov)
Component:	ACPICA-Core	Assignee:	Lin Ming (ming.m.lin)
Status:	CLOSED CODE_FIX
Severity:	normal	CC:	acpi-bugzilla
Priority:	P2
Hardware:	i386
OS:	Linux
Kernel Version:	2.6	Subsystem:
Regression:	---	Bisected commit-id:
Attachments:	ASL code to reproduce bug.

Description Valery A Podrezov 2005-09-29 09:05:06 UTC

Most recent kernel where this bug did not occur:
Distribution:
Hardware Environment:
Software Environment:
Problem Description:

The Linux kernel ACPI interpreter fails the following
AML test when it is compiled into a simulator. So if an
OEM BIOS includes this code, Linux would fail. 

Steps to reproduce:

Run interpreter with the .asl demo code attached below.

Comment 1 Valery A Podrezov 2005-09-29 09:08:53 UTC

Created attachment 6186 [details]
ASL code to reproduce bug.

The attached demo program shows that if the BufferField or FieldUnit
type objects are elements of some Package and we attempt to retrieve
the values of those elements, than exception AE_AML_OPERAND_TYPE occurs.

INTERNAL BUG NUMBER

   118

Comment 2 Lin Ming 2007-08-20 01:24:46 UTC

Maybe it's NOT a bug.

The code of #1 failed in "LNotEqual(Local1, 0x59)", 
Local1 here is of type BufferField, but the Spec 30b says in section 17.5.66,
both arguments of LNotEqual must each evaluate to an integer, a string, or a buffer, 

---------------------------------------------------------------------------
Syntax
LNotEqual (Source1, Source2) => Boolean
Arguments
Source1 and Source2 must each evaluate to an integer, a string, or a buffer. The data type of Source1 dictates the required type of Source2. Source2 is implicitly converted if necessary to match the type of Source1.
---------------------------------------------------------------------------

Comment 3 Robert Moore 2007-10-11 16:14:21 UTC

I think that the BufferField and Field should be resolved to integers at the time the Packages are created, since the ACPI spec says that package elements can be "data objects" (Integers, Strings, Buffers, Packages) or "control method references").

I'll take this since I have that code open right now for a very similar problem.

Bob

Comment 4 Lin Ming 2007-11-07 18:00:02 UTC

This bug still exists at latest ACPICA (v20071019)

Comment 5 Lin Ming 2007-11-07 18:12:10 UTC

Oh, sorry, seems it's not a bug now.
since the BufferField and Field have been resolved to integers at the time the Packages are created.

Bob, shoule we close this bug now?

Comment 6 Lin Ming 2007-11-07 18:25:20 UTC

Close this bug.

In the latest ACPICA (v20071019), the BufferField and Field would be resolved to integers at the time the Packages are created, as per ACPI spec.

Comment 7 Len Brown 2007-12-05 19:36:38 UTC

Lin Ming reports this tests passes in 20071019.

Also, since this fix was cherry picked from ACPICA 20071019
and shipped in linux-2.6.24-rc4 per bug 9429, this bug is now closed.