ACPICA commit 767ee53354e0c4b7e8e7c57c6dd7bf569f0d52bb
There are issues related to the namespace/interpreter locks, which causes
several ACPI functionalities not specification compliant. The lock issues
were detectec when we were trying to fix the functionalities (please see
Link # [1] for the details).
What's the lock issues? Let's first look into the namespace/interpreter
lock usages inside of the object evaluation and the table loading which are
the key AML interpretion code paths:
Table loading:
acpi_ns_load_table
L(Namespace)
acpi_ns_parse_table
acpi_ns_one_complete_parse(LOAD_PASS1/LOAD_PASS2)
acpi_ds_load1_begion_op
acpi_ds_load1_end_op
acpi_ds_load2_begion_op
acpi_ds_load2_end_op
U(Namespace)
Object evaluation:
acpi_ns_evaluate
L(Interpreter)
acpi_ps_execute_method
acpi_ds_exec_begin_op
acpi_ds_exec_end_op
U(Interpreter)
acpi_ns_load_table
L(Namespace)
U(Namespace)
acpi_ev_initialize_region
L(Namespace)
U(Namespace)
address_space.Setup
address_space.Handler
acpi_os_wait_semaphore
acpi_os_acquire_mutex
acpi_os_sleep
L(Interpreter)
U(Interpreter)
L(Interpreter)
acpi_ex_resolve_node_to_value
U(Interpreter)
acpi_ns_check_return_value
Where:
1. L(Interpreter) means acquire(MTX_INTERPRETER);
2. U(Interpreter) means release(MTX_INTERPRETER);
3. L(Namespace) means acquire(MTX_NAMESPACE);
4. U(Namespace) means release(MTX_NAMESPACE);
We can see that acpi_ns_exec_module_code() (which invokes acpi_ns_evaluate) is
implemented in a deferred way just in order to avoid to reacquire the
namespace lock. This is in fact the root cause of many other ACPICA issues:
1. We now know for sure that the module code should be executed right in
place by the Windows AML interpreter. So in the current design, if
the region initializations/accesses or the table loadings (where the
namespace surely should be locked again) happening during the table
loading period, dead lock could happen because ACPICA never unlocks the
namespace during the AML interpretion.
2. ACPICA interpreter just ensures that all static namespace nodes (named
objects created during the acpi_load_tables()) are created
(acpi_ns_lookup()) with the correct lock held, but doesn't ensure that
the named objects created by the control method are created with the
same correct lock held. It requires the control methods to be executed
in a serial way after "loading a table", that's why ACPICA requires
method auto serialization.
This patch fixes these software design issues by extending interpreter
enter/exit APIs to hold both interpreter/namespace locks to ensure the lock
order correctness, so that we can get these code paths:
Table loading:
acpi_ns_load_table
E(Interpreter)
acpi_ns_parse_table
acpi_ns_one_complete_parse
acpi_ns_execute_table
X(Interpreter)
acpi_ns_load_table
acpi_ev_initialize_region
address_space.Setup
address_space.Handler
acpi_os_wait_semaphore
acpi_os_acquire_mutex
acpi_os_sleep
E(Interpreter)
X(Interpreter)
Object evaluation:
acpi_ns_evaluate
E(Interpreter)
acpi_ps_execute_method
X(Interpreter)
acpi_ns_load_table
acpi_ev_initialize_region
address_space.Setup
address_space.Handler
acpi_os_wait_semaphore
acpi_os_acquire_mutex
acpi_os_sleep
E(Interpreter)
X(Interpreter)
Where:
1. E(Interpreter) means acquire(MTX_INTERPRETER, MTX_NAMESPACE);
2. X(Interpreter) means release(MTX_NAMESPACE, MTX_INTERPRETER);
After this change, we can see:
1. All namespace nodes creations are locked by the namespace lock.
2. All namespace nodes referencing are locked with the same lock.
3. But we also can notice a defact that, all namespace nodes deletions
could be affected by this change. As a consequence,
acpi_ns_delete_namespace_subtree() may delete a static namespace node that
is still referenced by the interpreter (for example, the parser scopes).
Currently, we needn't worry about the last defact because in ACPICA, table
unloading is not fully functioning, its design strictly relies on the fact
that when the namespace deletion happens, either the AML table or the OSPMs
should have been notified and thus either the AML table or the OSPMs
shouldn't reference deletion-related namespace nodes during the namespace
deletion. And this change still works with the above restrictions applied.
While making this a-step-forward helps us to correct the wrong grammar to
pull many things back to the correct rail. And pulling things back to the
correct rail in return makes it possible for us to support fully
functioning table unloading after doing many cleanups.
While this patch is generated, all namespace locks are examined to ensure
that they can meet either of the following pattens:
1. L(Namespace)
U(Namespace)
2. E(Interpreter)
X(Interpreter)
3. E(Interpreter)
X(Interpreter)
L(Namespace)
U(Namespace)
E(Interpreter)
X(Interpreter)
We ensure this by adding X(Interpreter)/E(Interpreter) or removing
U(Namespace)/L(Namespace) for those currently are executed in the following
order:
E(Interpreter)
L(Namespace)
U(Namespace)
X(Interpreter)
And adding E(Interpreter)/X(Interpreter) for those currently are executed
in the following order:
X(Interpreter)
E(Interpreter)
Originally, the interpreter lock is held for the execution AML opcodes, the
namespace lock is held for the named object creation AML opcodes. Since
they are actually same in MS interpreter (can all be executed during the
table loading), we can combine the 2 locks and tune the locking code better
in this way. Lv Zheng.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=153541 # [1]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=121701 # [1]
Link: https://bugs.acpica.org/show_bug.cgi?id=1323
Link: https://github.com/acpica/acpica/commit/767ee533
Reported-and-tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reported-and-tested-by: Greg White <gwhite@kupulau.com>
Reported-and-tested-by: Dutch Guy <lucht_piloot@gmx.net>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPICA commit 0e24fb67cde08d7df7671d7d7b183490dc79707e
The MLC (Module Level Code) is an ACPICA terminology describing the AML
code out of any control method, its support is an indication of the
interpreter behavior during the table loading.
The original implementation of MLC in ACPICA had several issues:
1. Out of any control method, besides of the object creating opcodes, only
the code blocks wrapped by "If/Else/While" opcodes were supported.
2. The supported MLC code blocks were executed after loading the table
rather than being executed right in place.
============================================================
The demo of this order issue is as follows:
Name (OBJ1, 1)
If (CND1 == 1)
{
Name (OBJ2, 2)
}
Name (OBJ3, 3)
The original MLC support created OBJ2 after OBJ3's creation.
============================================================
Other than these limitations, MLC support in ACPICA looks correct. And
supporting this should be easy/natural for ACPICA, but enabling of this was
blocked by some ACPICA internal and OSPM specific initialization order
issues we've fixed recently. The wrong support started from the following
false bug fixing commit:
Commit: 7f0c826a43
Subject: ACPICA: Add support for module-level executable AML code
Commit: 9a884ab64a
Subject: ACPICA: Add additional module-level code support
...
We can confirm Windows interpreter behavior via reverse engineering means.
It can be proven that not only If/Else/While wrapped code blocks, all
opcodes can be executed at the module level, including operation region
accesses. And it can be proven that the MLC should be executed right in
place, not in such a deferred way executed after loading the table.
And the above facts indeed reflect the spec words around ACPI definition
block tables (DSDT/SSDT/...), the entire table and the Scope object is
defined by the AML specification in BNF style as:
AMLCode := def_block_header term_list
def_scope := scope_op pkg_length name_string term_list
The bodies of the scope opening terms (AMLCode/Scope) are all term_list,
thus the table loading should be no difference than the control method
evaluations as the body of the Method is also defined by the AML
specification as term_list:
def_method := method_op pkg_length name_string method_flags term_list
The only difference is: after evaluating control method, created named
objects may be freed due to no reference, while named objects created by
the table loading should only be freed after unloading the table.
So this patch follows the spec and the de-facto standard behavior, enables
the new grammar (term_list) for the table loading.
By doing so, beyond the fixes to the above issues, we can see additional
differences comparing to the old grammar based table loading:
1. Originally, beyond the scope opening terms (AMLCode/Scope),
If/Else/While wrapped code blocks under the scope creating terms
(Device/power_resource/Processor/thermal_zone) are also supported as
deferred MLC, which violates the spec defined grammar where object_list
is enforced. With MLC support improved as non-deferred, the interpreter
parses such scope creating terms as term_list rather object_list like the
scope opening terms.
After probing the Windows behavior and proving that it also parses these
terms as term_list, we submitted an ECR (Engineering Change Request) to
the ASWG (ACPI Specification Working Group) to clarify this. The ECR is
titled as "ASL Grammar Clarification for Executable AML Opcodes" and has
been accepted by the ASWG. The new grammar will appear in ACPI
specification 6.2.
2. Originally, Buffer/Package/operation_region/create_XXXField/bank_field
arguments are evaluated in a deferred way after loading the table. With
MLC support improved, they are also parsed right in place during the
table loading.
This is also Windows compliant and the only difference is the removal
of the debugging messages implemented before acpi_ds_execute_arguments(),
see Link # [1] for the details. A previous commit should have ensured
that acpi_check_address_range() won't regress.
Note that enabling this feature may cause regressions due to long term
Linux ACPI support on top of the wrong grammar. So this patch also prepares
a global option to be used to roll back to the old grammar during the
period between a regression is reported and the regression is
root-cause-fixed. Lv Zheng.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=112911 # [1]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=117671 # [1]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=153541 # [1]
Link: https://github.com/acpica/acpica/issues/122
Link: https://bugs.acpica.org/show_bug.cgi?id=963
Link: https://github.com/acpica/acpica/commit/0e24fb67
Reported-and-tested-by: Chris Bainbridge <chris.bainbridge@gmail.com>
Reported-by: Ehsan <dashesy@gmail.com>
Reported-and-tested-by: Dutch Guy <lucht_piloot@gmx.net>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There is a lock order issue in acpi_load_tables(). The namespace lock
is held before holding the interpreter lock.
With ACPI_MUTEX_DEBUG enabled in the kernel, this is printed to the
log during boot:
[ 0.885699] ACPI Error: Invalid acquire order: Thread 405884224 owns [ACPI_MTX_Namespace], wants [ACPI_MTX_Interpreter] (20160422/utmutex-263)
[ 0.885881] ACPI Error: Could not acquire AML Interpreter mutex (20160422/exutils-95)
[ 0.893846] ACPI Error: Mutex [0x0] is not acquired, cannot release (20160422/utmutex-326)
[ 0.894019] ACPI Error: Could not release AML Interpreter mutex (20160422/exutils-133)
The issue has been introduced by the following commit:
Commit: 2f38b1b16d
ACPICA Commit: bfe03ffcde8ed56a7eae38ea0b188aeb12f9c52e
Subject: ACPICA: Namespace: Fix a regression that MLC support triggers
dead lock in dynamic table loading
Which fixed a deadlock issue for acpi_ns_load_table() in
acpi_ex_add_table() but didn't take care of the lock order in
acpi_ns_load_table() correctly.
Originally (before the above commit), ACPICA used the
namespace/interpreter locks in the following 2 key code
paths:
1. Table loading:
acpi_ns_load_table
L(Namespace)
acpi_ns_parse_table
acpi_ns_one_complete_parse
U(Namespace)
2. Object evaluation:
acpi_ns_evaluate
L(Interpreter)
acpi_ps_execute_method
U(Interpreter)
acpi_ns_load_table
L(Namespace)
U(Namespace)
acpi_ev_initialize_region
L(Namespace)
U(Namespace)
address_space.setup
L(Namespace)
U(Namespace)
address_space.handler
L(Namespace)
U(Namespace)
acpi_os_wait_semaphore
acpi_os_acquire_mutex
acpi_os_sleep
L(Interpreter)
U(Interpreter)
During runtime, while acpi_ns_evaluate is called, the lock order is
always Interpreter -> Namespace.
In turn, the problematic commit acquires the locks in the following
order:
3. Table loading:
acpi_ns_load_table
L(Namespace)
acpi_ns_parse_table
L(Interpreter)
acpi_ns_one_complete_parse
U(Interpreter)
U(Namespace)
To fix the lock order issue, move the interpreter lock to
acpi_ns_load_table() to ensure the lock order correctness:
4. Table loading:
acpi_ns_load_table
L(Interpreter)
L(Namespace)
acpi_ns_parse_table
acpi_ns_one_complete_parse
U(Namespace)
U(Interpreter)
However, this doesn't fix the current design issues related to the
namespace lock. For example, we can notice that in acpi_ns_evaluate(),
outside of acpi_ns_load_table(), the namespace objects may be created
by the named object creation control methods. And the creation of
the method-owned namespace objects are not locked by the namespace
lock. This patch doesn't try to fix such kind of existing issues.
Fixes: 2f38b1b16d (ACPICA: Namespace: Fix a regression that MLC support triggers dead lock in dynamic table loading)
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The new module-level code (MLC) approach invokes MLC on the per-table
basis, but the dynamic loading support of this is incorrect because
of the lock order:
acpi_ns_evaluate
acpi_ex_enter_intperter
acpi_ns_load_table (triggered by Load opcode)
acpi_ns_exec_module_code_list
acpi_ex_enter_intperter
The regression is introduced by the following commit:
Commit: 2785ce8d0d
ACPICA Commit: 071eff738c59eda1792ac24b3b688b61691d7e7c
Subject: ACPICA: Add per-table execution of module-level code
This patch fixes this regression by unlocking the interpreter lock
before invoking MLC. However, the unlocking is done to the
acpi_ns_load_table(), in which the interpreter lock should be locked
by acpi_ns_parse_table() but it wasn't.
Fixes: 2785ce8d0d (ACPICA: Add per-table execution of module-level code)
Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Cc: 4.5+ <stable@vger.kernel.org> # 4.5+
[ rjw : Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
All tool/utility signons.
Dual-license module header.
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPICA commit dfa394471f6c01b2ee9433dbc143ec70cb9bca72
Mostly indentation inconsistencies across the code. Split
some long lines, etc.
Link: https://github.com/acpica/acpica/commit/dfa39447
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPICA commit afb52611dbe7403551f93504d3798534f5c343f4
This patch cleans up the code of assigning the AML address to the
union acpi_operand_object.
The idea behind this cleanup is:
The AML address of the union acpi_operand_object should always be determined at
the point where the object is encountered. It should be started from the
first byte of the object. For example, the opcode of the object, the name
string of the user_term object, or the first byte of the packaged object
(where a pkg_length is prefixed). So it's not cleaner to have it assigned
here and there in the entire ACPICA source tree.
There are some special cases for the internal opcodes, before cleaning up
the internal opcodes, we should also determine the rules for the AML
addresses of the internal opcodes:
1. INT_NAMEPATH_OP: the address of the first byte for the name_string.
2. INT_METHODCALL_OP: the address of the first byte for the name_string.
3. INT_BYTELIST_OP: the address of the first byte for the byte_data list.
4. INT_EVAL_SUBTREE_OP: the address of the first byte for the
Region/Package/Buffer/bank_field/Field arguments.
5. INT_NAMEDFIELD_OP: the address to the name_seg.
6. INT_RESERVEDFIELD_OP: the address to the 0x00 prefix.
7. INT_ACCESSFIELD_OP: the address to the 0x01 prefix.
8. INT_CONNECTION_OP: the address to the 0x02 prefix.
9: INT_EXTACCESSFIELD_OP: the address to the 0x03 prefix.
10.INT_RETURN_VALUE_OP: the address of the replaced operand.
11.computational_data: the address to the
Byte/Word/Dword/Qword/string_prefix.
Before cleaning up the internal root scope of the aml_walk, turning it into
the term_list, we need to remember the aml_start address as the "Aml"
attribute for the union acpi_operand_object created by acpi_ps_create_scope_op().
Finally, we can delete some redundant AML address assignment in psloop.c.
Link: https://github.com/acpica/acpica/commit/afb52611
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch reduces divergences in parser/namespace components so that the
follow-up linuxized ACPICA upstream commits can be directly merged.
Including the fix to an indent issue reported and fixed by Zhouyi Zhou.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Zhouyi Zhou <yizhouzhou@ict.ac.cn>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPICA commit 27415c82fcecf467446f66d1007a0691cc5f3709
This patch adds OSDT (Override System Definition Table) support.
When OSDT is loaded, conflict namespace objects will be overridden
by the AML interpreter. Bob Moore, Lv Zheng.
Link: https://github.com/acpica/acpica/commit/27415c82
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPICA commit 8990e73ab2aa15d6a0068b860ab54feff25bee36
Link: https://github.com/acpica/acpica/commit/8990e73a
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Update ACPICA copyrights to 2014. Includes all source headers and
signons for the various tools.
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
It is reported by kernel build test systems that all ACPICA source
files in the kernel tree have incorrect label indentation. This
patch changes default indent option used in the release process to
fix this bug. Lv Zheng.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Includes all source headers and signons for the various tools.
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This makes all comments consistent.
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Update all copyrights to 2012.
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
With only a few exceptions, ACPICA does not use signed integers.
Therefore, %d is incorrect.
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Add 2010 copyright to all module headers and signons, including
the Linux header. This affects virtually every file in the ACPICA
core subsystem, iASL compiler, and all utilities.
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Split long lines, update comments.
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
