diff mbox series

[RFC,7/8] acpi: srat: cxl: Skip zero length CXL fixed memory windows.

Message ID 20240529171236.32002-8-Jonathan.Cameron@huawei.com (mailing list archive)
State New, archived
Headers show
Series arm64/memblock: Handling of CXL Fixed Memory Windows. | expand

Commit Message

Jonathan Cameron May 29, 2024, 5:12 p.m. UTC
One reported platform uses this nonsensical entry to represent
a disable CFWMS. The acpi_cxl driver already correctly errors
out on seeing this, but that leaves an additional confusing node
in /sys/devices/system/nodes/possible plus wastes some space.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
 drivers/acpi/numa/srat.c | 5 +++++
 1 file changed, 5 insertions(+)

Comments

Yuquan Wang Aug. 1, 2024, 7:55 a.m. UTC | #1
On Wed, May 29, 2024 at 06:12:35PM +0100, Jonathan Cameron wrote:
> One reported platform uses this nonsensical entry to represent
> a disable CFWMS. The acpi_cxl driver already correctly errors
> out on seeing this, but that leaves an additional confusing node
> in /sys/devices/system/nodes/possible plus wastes some space.
> 
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> ---
>  drivers/acpi/numa/srat.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/acpi/numa/srat.c b/drivers/acpi/numa/srat.c
> index e3f26e71637a..28c963d5c51f 100644
> --- a/drivers/acpi/numa/srat.c
> +++ b/drivers/acpi/numa/srat.c
> @@ -329,6 +329,11 @@ static int __init acpi_parse_cfmws(union acpi_subtable_headers *header,
>  	int node;
>  
>  	cfmws = (struct acpi_cedt_cfmws *)header;
> +
> +	/* At least one firmware reports disabled entries with size 0 */
> +	if (cfmws->window_size == 0)
> +		return 0;
> +
>  	start = cfmws->base_hpa;
>  	end = cfmws->base_hpa + cfmws->window_size;
>  
> -- 
> 2.39.2
>

Tested-off-by: Yuquan Wang <wangyuquan1236@phytium.com.cn>
diff mbox series

Patch

diff --git a/drivers/acpi/numa/srat.c b/drivers/acpi/numa/srat.c
index e3f26e71637a..28c963d5c51f 100644
--- a/drivers/acpi/numa/srat.c
+++ b/drivers/acpi/numa/srat.c
@@ -329,6 +329,11 @@  static int __init acpi_parse_cfmws(union acpi_subtable_headers *header,
 	int node;
 
 	cfmws = (struct acpi_cedt_cfmws *)header;
+
+	/* At least one firmware reports disabled entries with size 0 */
+	if (cfmws->window_size == 0)
+		return 0;
+
 	start = cfmws->base_hpa;
 	end = cfmws->base_hpa + cfmws->window_size;