RE: [PATCH v3 1/5] ACPICA: Namespace: Fix a regression that MLC support triggers dead lock in dynamic table loading

["Zheng, Lv" <lv.zheng@intel.com>]

Hi, Mika

> From: Mika Westerberg [mailto:mika.westerberg@linux.intel.com]
> Subject: Re: [PATCH v3 1/5] ACPICA: Namespace: Fix a regression that MLC
> support triggers dead lock in dynamic table loading
> 
> On Mon, Jun 20, 2016 at 05:07:22PM +0800, Lv Zheng wrote:
> > The new MLC approach invokes MLC 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: 2785ce8d0da1cac9d8f78615e116cf929e9a9123
> >   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
> > wasn't. Reported by Mika Westerberg. Fixed by Lv Zheng.
> >
> > Fixes: 2785ce8d0da1 ("ACPICA: Add per-table execution of module-level
> code")
> > Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
> > Signed-off-by: Lv Zheng <lv.zheng@intel.com>
> > ---
> >  drivers/acpi/acpica/exconfig.c |    2 ++
> >  drivers/acpi/acpica/nsparse.c  |    8 ++++++--
> >  2 files changed, 8 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/acpi/acpica/exconfig.c
> b/drivers/acpi/acpica/exconfig.c
> > index a1d177d..21932d6 100644
> > --- a/drivers/acpi/acpica/exconfig.c
> > +++ b/drivers/acpi/acpica/exconfig.c
> > @@ -108,7 +108,9 @@ acpi_ex_add_table(u32 table_index,
> >
> >  	/* Add the table to the namespace */
> >
> > +	acpi_ex_exit_interpreter();
> >  	status = acpi_ns_load_table(table_index, parent_node);
> > +	acpi_ex_enter_interpreter();
> >  	if (ACPI_FAILURE(status)) {
> >  		acpi_ut_remove_reference(obj_desc);
> >  		*ddb_handle = NULL;
> > diff --git a/drivers/acpi/acpica/nsparse.c b/drivers/acpi/acpica/nsparse.c
> > index f631a47..0d29383 100644
> > --- a/drivers/acpi/acpica/nsparse.c
> > +++ b/drivers/acpi/acpica/nsparse.c
> > @@ -170,6 +170,8 @@ acpi_ns_parse_table(u32 table_index, struct
> acpi_namespace_node *start_node)
> >
> >  	ACPI_FUNCTION_TRACE(ns_parse_table);
> >
> > +	acpi_ex_enter_interpreter();
> 
> I'm getting these:
> 
> drivers/acpi/acpica/nsparse.c: In function ‘acpi_ns_parse_table’:
> drivers/acpi/acpica/nsparse.c:173:2: error: implicit declaration of function
> ‘acpi_ex_enter_interpreter’ [-Werror=implicit-function-declaration]
>   acpi_ex_enter_interpreter();
>   ^
> drivers/acpi/acpica/nsparse.c:210:2: error: implicit declaration of function
> ‘acpi_ex_exit_interpreter’ [-Werror=implicit-function-declaration]
>   acpi_ex_exit_interpreter();
>   ^
> cc1: some warnings being treated as errors
> 
> Do I need to have some other patch applied before this?
[Lv Zheng] 
The acinterp.h inclusion is in PATCH 03.
I'll re-send the series with this corrected.

Thanks and best regards
-Lv