diff mbox series

[03/18] cxl: Add checksum verification to CDAT from CXL

Message ID 167571658747.587790.17252249256706733075.stgit@djiang5-mobl3.local
State New
Headers show
Series cxl: Add support for QTG ID retrieval for CXL subsystem | expand

Commit Message

Dave Jiang Feb. 6, 2023, 8:49 p.m. UTC
A CDAT table is available from a CXL device. The table is read by the
driver and cached in software. With the CXL subsystem needing to parse the
CDAT table, the checksum should be verified. Add checksum verification
after the CDAT table is read from device.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
---
 drivers/cxl/core/pci.c |   11 +++++++++++
 1 file changed, 11 insertions(+)
diff mbox series

Patch

diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
index 57764e9cd19d..a24dac36bedd 100644
--- a/drivers/cxl/core/pci.c
+++ b/drivers/cxl/core/pci.c
@@ -3,6 +3,7 @@ 
 #include <linux/io-64-nonatomic-lo-hi.h>
 #include <linux/device.h>
 #include <linux/delay.h>
+#include <linux/acpi.h>
 #include <linux/pci.h>
 #include <linux/pci-doe.h>
 #include <cxlpci.h>
@@ -592,6 +593,7 @@  void read_cdat_data(struct cxl_port *port)
 	struct device *dev = &port->dev;
 	struct device *uport = port->uport;
 	size_t cdat_length;
+	acpi_status status;
 	int rc;
 
 	cdat_doe = find_cdat_doe(uport);
@@ -620,5 +622,14 @@  void read_cdat_data(struct cxl_port *port)
 		port->cdat.length = 0;
 		dev_err(dev, "CDAT data read error\n");
 	}
+
+	status = acpi_ut_verify_cdat_checksum(port->cdat.table, port->cdat.length);
+	if (status != AE_OK) {
+		/* Don't leave table data allocated on error */
+		devm_kfree(dev, port->cdat.table);
+		port->cdat.table = NULL;
+		port->cdat.length = 0;
+		dev_err(dev, "CDAT data checksum error\n");
+	}
 }
 EXPORT_SYMBOL_NS_GPL(read_cdat_data, CXL);