[PATCH v3] cxl/acpi: Verify CHBS length for CXL2.0
From: Li Zhijian
Date: Wed Apr 09 2025 - 21:07:27 EST
Per CXL Spec r3.1 Table 9-21, both CXL1.1 and CXL2.0 have defined their
own length, verify it to avoid an invalid CHBS.
Additionally, this patch also removes the redundant macro CXL_RCRB_SIZE,
favoring the use of `ACPI_CEDT_CHBS_LENGTH_CXL11`, which offers clearer
semantic meaning.
Reviewed-by: Gregory Price <gourry@xxxxxxxxxx>
Signed-off-by: Li Zhijian <lizhijian@xxxxxxxxxxx>
---
V3:
- say more words in removing CXL_RCRB_SIZE # Alison
- Collected Reviewed-by
V2: don't factor out, just validate # Dan
---
drivers/cxl/acpi.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c
index cb14829bb9be..2e63e50b2c40 100644
--- a/drivers/cxl/acpi.c
+++ b/drivers/cxl/acpi.c
@@ -11,8 +11,6 @@
#include "cxlpci.h"
#include "cxl.h"
-#define CXL_RCRB_SIZE SZ_8K
-
struct cxl_cxims_data {
int nr_maps;
u64 xormaps[] __counted_by(nr_maps);
@@ -478,8 +476,10 @@ static int cxl_get_chbs_iter(union acpi_subtable_headers *header, void *arg,
chbs = (struct acpi_cedt_chbs *) header;
- if (chbs->cxl_version == ACPI_CEDT_CHBS_VERSION_CXL11 &&
- chbs->length != CXL_RCRB_SIZE)
+ if ((chbs->cxl_version == ACPI_CEDT_CHBS_VERSION_CXL11 &&
+ chbs->length != ACPI_CEDT_CHBS_LENGTH_CXL11) ||
+ (chbs->cxl_version == ACPI_CEDT_CHBS_VERSION_CXL20 &&
+ chbs->length != ACPI_CEDT_CHBS_LENGTH_CXL20))
return 0;
if (!chbs->base)
--
2.47.0