Merge tag 'cxl-fixes-7.0-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl

Pull Compute Express Link (CXL) fixes from Dave Jiang:

 - Adjust the startup priority of cxl_pmem to be higher than that of
   cxl_acpi

 - Use proper endpoint validity check upon sanitize

 - Avoid incorrect DVSEC fallback when HDM decoders are enabled

 - Fix CXL_ACPI and CXL_PMEM Kconfig tristate mismatch

 - Fix leakage in __construct_region()

 - Fix use after free of parent_port in cxl_detach_ep()

* tag 'cxl-fixes-7.0-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl:
  cxl: Adjust the startup priority of cxl_pmem to be higher than that of cxl_acpi
  cxl/mbox: Use proper endpoint validity check upon sanitize
  cxl/hdm: Avoid incorrect DVSEC fallback when HDM decoders are enabled
  cxl/acpi: Fix CXL_ACPI and CXL_PMEM Kconfig tristate mismatch
  cxl/region: Fix leakage in __construct_region()
  cxl/port: Fix use after free of parent_port in cxl_detach_ep()

Author: torvalds

drivers/cxl/Kconfig

@@ -59,6 +59,7 @@ config CXL_ACPI
 	tristate "CXL ACPI: Platform Support"
 	depends on ACPI
 	depends on ACPI_NUMA
+	depends on CXL_PMEM || !CXL_PMEM
 	default CXL_BUS
 	select ACPI_TABLE_LIB
 	select ACPI_HMAT

drivers/cxl/core/hdm.c

@@ -94,7 +94,6 @@ static bool should_emulate_decoders(struct cxl_endpoint_dvsec_info *info)
 	struct cxl_hdm *cxlhdm;
 	void __iomem *hdm;
 	u32 ctrl;
-	int i;
 
 	if (!info)
 		return false;
@@ -113,22 +112,16 @@ static bool should_emulate_decoders(struct cxl_endpoint_dvsec_info *info)
 		return false;
 
 	/*
-	 * If any decoders are committed already, there should not be any
-	 * emulated DVSEC decoders.
+	 * If HDM decoders are globally enabled, do not fall back to DVSEC
+	 * range emulation. Zeroed decoder registers after region teardown
+	 * do not imply absence of HDM capability.
+	 *
+	 * Falling back to DVSEC here would treat the decoder as AUTO and
+	 * may incorrectly latch default interleave settings.
 	 */
-	for (i = 0; i < cxlhdm->decoder_count; i++) {
-		ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(i));
-		dev_dbg(&info->port->dev,
-			"decoder%d.%d: committed: %ld base: %#x_%.8x size: %#x_%.8x\n",
-			info->port->id, i,
-			FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMITTED, ctrl),
-			readl(hdm + CXL_HDM_DECODER0_BASE_HIGH_OFFSET(i)),
-			readl(hdm + CXL_HDM_DECODER0_BASE_LOW_OFFSET(i)),
-			readl(hdm + CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(i)),
-			readl(hdm + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(i)));
-		if (FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMITTED, ctrl))
-			return false;
-	}
+	ctrl = readl(hdm + CXL_HDM_DECODER_CTRL_OFFSET);
+	if (ctrl & CXL_HDM_DECODER_ENABLE)
+		return false;
 
 	return true;
 }

drivers/cxl/core/mbox.c

@@ -1301,7 +1301,7 @@ int cxl_mem_sanitize(struct cxl_memdev *cxlmd, u16 cmd)
 	 * Require an endpoint to be safe otherwise the driver can not
 	 * be sure that the device is unmapped.
 	 */
-	if (endpoint && cxl_num_decoders_committed(endpoint) == 0)
+	if (cxlmd->dev.driver && cxl_num_decoders_committed(endpoint) == 0)
 		return __cxl_mem_sanitize(mds, cmd);
 
 	return -EBUSY;

drivers/cxl/core/port.c

@@ -552,10 +552,13 @@ static void cxl_port_release(struct device *dev)
 	xa_destroy(&port->dports);
 	xa_destroy(&port->regions);
 	ida_free(&cxl_port_ida, port->id);
-	if (is_cxl_root(port))
+
+	if (is_cxl_root(port)) {
 		kfree(to_cxl_root(port));
-	else
+	} else {
+		put_device(dev->parent);
 		kfree(port);
+	}
 }
 
 static ssize_t decoders_committed_show(struct device *dev,
@@ -707,6 +710,7 @@ static struct cxl_port *cxl_port_alloc(struct device *uport_dev,
 		struct cxl_port *iter;
 
 		dev->parent = &parent_port->dev;
+		get_device(dev->parent);
 		port->depth = parent_port->depth + 1;
 		port->parent_dport = parent_dport;
 

drivers/cxl/core/region.c

@@ -3854,8 +3854,10 @@ static int __construct_region(struct cxl_region *cxlr,
 	}
 
 	rc = sysfs_update_group(&cxlr->dev.kobj, &cxl_region_group);
-	if (rc)
+	if (rc) {
+		kfree(res);
 		return rc;
+	}
 
 	rc = insert_resource(cxlrd->res, res);
 	if (rc) {

drivers/cxl/pmem.c

@@ -554,7 +554,7 @@ static __exit void cxl_pmem_exit(void)
 
 MODULE_DESCRIPTION("CXL PMEM: Persistent Memory Support");
 MODULE_LICENSE("GPL v2");
-module_init(cxl_pmem_init);
+subsys_initcall(cxl_pmem_init);
 module_exit(cxl_pmem_exit);
 MODULE_IMPORT_NS("CXL");
 MODULE_ALIAS_CXL(CXL_DEVICE_NVDIMM_BRIDGE);