2020-09-29 08:22:26

by Aaron Ma

Subject: [PATCH] platform/x86: thinkpad_acpi: re-initialize acpi buffer size when reuse

Evaluating acpi _BCL could be failed, then acpi buffer size will be set
to 0. When reuse this acpi buffer, AE_BUFFER_OVERFLOW will be triggered.

Re-initialize buffer size will make acpi evaluate successfully.

Signed-off-by: Aaron Ma <[email protected]>
---
drivers/platform/x86/thinkpad_acpi.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index 9c4df41687a3..477d63c49c04 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -6829,8 +6829,10 @@ static int __init tpacpi_query_bcl_levels(acpi_handle handle)
list_for_each_entry(child, &device->children, node) {
acpi_status status = acpi_evaluate_object(child->handle, "_BCL",
NULL, &buffer);
- if (ACPI_FAILURE(status))
+ if (ACPI_FAILURE(status)) {
+ buffer.length = ACPI_ALLOCATE_BUFFER;
continue;
+ }

obj = (union acpi_object *)buffer.pointer;
if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
--
2.28.0

2020-09-30 13:57:37

by Andy Shevchenko

Subject: Re: [PATCH] platform/x86: thinkpad_acpi: re-initialize acpi buffer size when reuse

On Tue, Sep 29, 2020 at 11:20 AM Aaron Ma <[email protected]> wrote:
>
> Evaluating acpi _BCL could be failed, then acpi buffer size will be set

'could be failed' -> 'could fail'

> to 0. When reuse this acpi buffer, AE_BUFFER_OVERFLOW will be triggered.
>
> Re-initialize buffer size will make acpi evaluate successfully.

acpi -> ACPI in all cases above.

Fixes tag, please?

> Signed-off-by: Aaron Ma <[email protected]>

Code is okay.

--
With Best Regards,
Andy Shevchenko

2020-10-02 17:11:19

by Aaron Ma

Subject: [PATCH v2] platform/x86: thinkpad_acpi: re-initialize ACPI buffer size when reuse

Evaluating ACPI _BCL could fail, then ACPI buffer size will be set to 0.
When reuse this ACPI buffer, AE_BUFFER_OVERFLOW will be triggered.

Re-initialize buffer size will make ACPI evaluate successfully.

Fixes: 46445b6b896fd ("thinkpad-acpi: fix handle locate for video and query of _BCL")
Signed-off-by: Aaron Ma <[email protected]>
---
drivers/platform/x86/thinkpad_acpi.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index 9c4df41687a3..477d63c49c04 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -6829,8 +6829,10 @@ static int __init tpacpi_query_bcl_levels(acpi_handle handle)
list_for_each_entry(child, &device->children, node) {
acpi_status status = acpi_evaluate_object(child->handle, "_BCL",
NULL, &buffer);
- if (ACPI_FAILURE(status))
+ if (ACPI_FAILURE(status)) {
+ buffer.length = ACPI_ALLOCATE_BUFFER;
continue;
+ }

obj = (union acpi_object *)buffer.pointer;
if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
--
2.28.0