Merge tag 'cxl-fixes-6.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl

Pull cxl fixes from Ira Weiny:
 "The bulk of these fixes center around an initialization order bug
  reported by Gregory Price and some additional fall out from the
  debugging effort.

  In summary, cxl_acpi and cxl_mem race and previously worked because of
  a bus_rescan_devices() while testing without modules built in.

  Unfortunately with modules built in the rescan would fail due to the
  cxl_port driver being registered late via the build order. Furthermore
  it was found bus_rescan_devices() did not guarantee a probe barrier
  which CXL was expecting. Additional fixes to cxl-test and decoder
  allocation came along as they were found in this debugging effort.

  The other fixes are pretty minor but one affects trace point data seen
  by user space.

  Summary:

   - Fix crashes when running with cxl-test code

   - Fix Trace DRAM Event Record field decodes

   - Fix module/built in initialization order errors

   - Fix use after free on decoder shutdowns

   - Fix out of order decoder allocations

   - Improve cxl-test to better reflect real world systems"

* tag 'cxl-fixes-6.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl:
  cxl/test: Improve init-order fidelity relative to real-world systems
  cxl/port: Prevent out-of-order decoder allocation
  cxl/port: Fix use-after-free, permit out-of-order decoder shutdown
  cxl/acpi: Ensure ports ready at cxl_acpi_probe() return
  cxl/port: Fix cxl_bus_rescan() vs bus_rescan_devices()
  cxl/port: Fix CXL port initialization order when the subsystem is built-in
  cxl/events: Fix Trace DRAM Event Record
  cxl/core: Return error when cxl_endpoint_gather_bandwidth() handles a non-PCI device

2 files changed, 109 insertions, 92 deletions

diff --git a/tools/testing/cxl/test/cxl.c b/tools/testing/cxl/test/cxl.c
index 90d5afd52dd0..050725afa45d 100644
--- a/tools/testing/cxl/test/cxl.c
+++ b/tools/testing/cxl/test/cxl.c
@@ -693,26 +693,22 @@ static int mock_decoder_commit(struct cxl_decoder *cxld)
 	return 0;
 }
 
-static int mock_decoder_reset(struct cxl_decoder *cxld)
+static void mock_decoder_reset(struct cxl_decoder *cxld)
 {
 	struct cxl_port *port = to_cxl_port(cxld->dev.parent);
 	int id = cxld->id;
 
 	if ((cxld->flags & CXL_DECODER_F_ENABLE) == 0)
-		return 0;
+		return;
 
 	dev_dbg(&port->dev, "%s reset\n", dev_name(&cxld->dev));
-	if (port->commit_end != id) {
+	if (port->commit_end == id)
+		cxl_port_commit_reap(cxld);
+	else
 		dev_dbg(&port->dev,
 			"%s: out of order reset, expected decoder%d.%d\n",
 			dev_name(&cxld->dev), port->id, port->commit_end);
-		return -EBUSY;
-	}
-
-	port->commit_end--;
 	cxld->flags &= ~CXL_DECODER_F_ENABLE;
-
-	return 0;
 }
 
 static void default_mock_decoder(struct cxl_decoder *cxld)
@@ -1062,7 +1058,7 @@ static void mock_companion(struct acpi_device *adev, struct device *dev)
 #define SZ_64G (SZ_32G * 2)
 #endif
 
-static __init int cxl_rch_init(void)
+static __init int cxl_rch_topo_init(void)
 {
 	int rc, i;
 
@@ -1090,30 +1086,8 @@ static __init int cxl_rch_init(void)
 			goto err_bridge;
 	}
 
-	for (i = 0; i < ARRAY_SIZE(cxl_rcd); i++) {
-		int idx = NR_MEM_MULTI + NR_MEM_SINGLE + i;
-		struct platform_device *rch = cxl_rch[i];
-		struct platform_device *pdev;
-
-		pdev = platform_device_alloc("cxl_rcd", idx);
-		if (!pdev)
-			goto err_mem;
-		pdev->dev.parent = &rch->dev;
-		set_dev_node(&pdev->dev, i % 2);
-
-		rc = platform_device_add(pdev);
-		if (rc) {
-			platform_device_put(pdev);
-			goto err_mem;
-		}
-		cxl_rcd[i] = pdev;
-	}
-
 	return 0;
 
-err_mem:
-	for (i = ARRAY_SIZE(cxl_rcd) - 1; i >= 0; i--)
-		platform_device_unregister(cxl_rcd[i]);
 err_bridge:
 	for (i = ARRAY_SIZE(cxl_rch) - 1; i >= 0; i--) {
 		struct platform_device *pdev = cxl_rch[i];
@@ -1127,12 +1101,10 @@ err_bridge:
 	return rc;
 }
 
-static void cxl_rch_exit(void)
+static void cxl_rch_topo_exit(void)
 {
 	int i;
 
-	for (i = ARRAY_SIZE(cxl_rcd) - 1; i >= 0; i--)
-		platform_device_unregister(cxl_rcd[i]);
 	for (i = ARRAY_SIZE(cxl_rch) - 1; i >= 0; i--) {
 		struct platform_device *pdev = cxl_rch[i];
 
@@ -1143,7 +1115,7 @@ static void cxl_rch_exit(void)
 	}
 }
 
-static __init int cxl_single_init(void)
+static __init int cxl_single_topo_init(void)
 {
 	int i, rc;
 
@@ -1228,29 +1200,8 @@ static __init int cxl_single_init(void)
 		cxl_swd_single[i] = pdev;
 	}
 
-	for (i = 0; i < ARRAY_SIZE(cxl_mem_single); i++) {
-		struct platform_device *dport = cxl_swd_single[i];
-		struct platform_device *pdev;
-
-		pdev = platform_device_alloc("cxl_mem", NR_MEM_MULTI + i);
-		if (!pdev)
-			goto err_mem;
-		pdev->dev.parent = &dport->dev;
-		set_dev_node(&pdev->dev, i % 2);
-
-		rc = platform_device_add(pdev);
-		if (rc) {
-			platform_device_put(pdev);
-			goto err_mem;
-		}
-		cxl_mem_single[i] = pdev;
-	}
-
 	return 0;
 
-err_mem:
-	for (i = ARRAY_SIZE(cxl_mem_single) - 1; i >= 0; i--)
-		platform_device_unregister(cxl_mem_single[i]);
 err_dport:
 	for (i = ARRAY_SIZE(cxl_swd_single) - 1; i >= 0; i--)
 		platform_device_unregister(cxl_swd_single[i]);
@@ -1273,12 +1224,10 @@ err_bridge:
 	return rc;
 }
 
-static void cxl_single_exit(void)
+static void cxl_single_topo_exit(void)
 {
 	int i;
 
-	for (i = ARRAY_SIZE(cxl_mem_single) - 1; i >= 0; i--)
-		platform_device_unregister(cxl_mem_single[i]);
 	for (i = ARRAY_SIZE(cxl_swd_single) - 1; i >= 0; i--)
 		platform_device_unregister(cxl_swd_single[i]);
 	for (i = ARRAY_SIZE(cxl_swu_single) - 1; i >= 0; i--)
@@ -1295,6 +1244,91 @@ static void cxl_single_exit(void)
 	}
 }
 
+static void cxl_mem_exit(void)
+{
+	int i;
+
+	for (i = ARRAY_SIZE(cxl_rcd) - 1; i >= 0; i--)
+		platform_device_unregister(cxl_rcd[i]);
+	for (i = ARRAY_SIZE(cxl_mem_single) - 1; i >= 0; i--)
+		platform_device_unregister(cxl_mem_single[i]);
+	for (i = ARRAY_SIZE(cxl_mem) - 1; i >= 0; i--)
+		platform_device_unregister(cxl_mem[i]);
+}
+
+static int cxl_mem_init(void)
+{
+	int i, rc;
+
+	for (i = 0; i < ARRAY_SIZE(cxl_mem); i++) {
+		struct platform_device *dport = cxl_switch_dport[i];
+		struct platform_device *pdev;
+
+		pdev = platform_device_alloc("cxl_mem", i);
+		if (!pdev)
+			goto err_mem;
+		pdev->dev.parent = &dport->dev;
+		set_dev_node(&pdev->dev, i % 2);
+
+		rc = platform_device_add(pdev);
+		if (rc) {
+			platform_device_put(pdev);
+			goto err_mem;
+		}
+		cxl_mem[i] = pdev;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(cxl_mem_single); i++) {
+		struct platform_device *dport = cxl_swd_single[i];
+		struct platform_device *pdev;
+
+		pdev = platform_device_alloc("cxl_mem", NR_MEM_MULTI + i);
+		if (!pdev)
+			goto err_single;
+		pdev->dev.parent = &dport->dev;
+		set_dev_node(&pdev->dev, i % 2);
+
+		rc = platform_device_add(pdev);
+		if (rc) {
+			platform_device_put(pdev);
+			goto err_single;
+		}
+		cxl_mem_single[i] = pdev;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(cxl_rcd); i++) {
+		int idx = NR_MEM_MULTI + NR_MEM_SINGLE + i;
+		struct platform_device *rch = cxl_rch[i];
+		struct platform_device *pdev;
+
+		pdev = platform_device_alloc("cxl_rcd", idx);
+		if (!pdev)
+			goto err_rcd;
+		pdev->dev.parent = &rch->dev;
+		set_dev_node(&pdev->dev, i % 2);
+
+		rc = platform_device_add(pdev);
+		if (rc) {
+			platform_device_put(pdev);
+			goto err_rcd;
+		}
+		cxl_rcd[i] = pdev;
+	}
+
+	return 0;
+
+err_rcd:
+	for (i = ARRAY_SIZE(cxl_rcd) - 1; i >= 0; i--)
+		platform_device_unregister(cxl_rcd[i]);
+err_single:
+	for (i = ARRAY_SIZE(cxl_mem_single) - 1; i >= 0; i--)
+		platform_device_unregister(cxl_mem_single[i]);
+err_mem:
+	for (i = ARRAY_SIZE(cxl_mem) - 1; i >= 0; i--)
+		platform_device_unregister(cxl_mem[i]);
+	return rc;
+}
+
 static __init int cxl_test_init(void)
 {
 	int rc, i;
@@ -1407,29 +1441,11 @@ static __init int cxl_test_init(void)
 		cxl_switch_dport[i] = pdev;
 	}
 
-	for (i = 0; i < ARRAY_SIZE(cxl_mem); i++) {
-		struct platform_device *dport = cxl_switch_dport[i];
-		struct platform_device *pdev;
-
-		pdev = platform_device_alloc("cxl_mem", i);
-		if (!pdev)
-			goto err_mem;
-		pdev->dev.parent = &dport->dev;
-		set_dev_node(&pdev->dev, i % 2);
-
-		rc = platform_device_add(pdev);
-		if (rc) {
-			platform_device_put(pdev);
-			goto err_mem;
-		}
-		cxl_mem[i] = pdev;
-	}
-
-	rc = cxl_single_init();
+	rc = cxl_single_topo_init();
 	if (rc)
-		goto err_mem;
+		goto err_dport;
 
-	rc = cxl_rch_init();
+	rc = cxl_rch_topo_init();
 	if (rc)
 		goto err_single;
 
@@ -1442,19 +1458,20 @@ static __init int cxl_test_init(void)
 
 	rc = platform_device_add(cxl_acpi);
 	if (rc)
-		goto err_add;
+		goto err_root;
+
+	rc = cxl_mem_init();
+	if (rc)
+		goto err_root;
 
 	return 0;
 
-err_add:
+err_root:
 	platform_device_put(cxl_acpi);
 err_rch:
-	cxl_rch_exit();
+	cxl_rch_topo_exit();
 err_single:
-	cxl_single_exit();
-err_mem:
-	for (i = ARRAY_SIZE(cxl_mem) - 1; i >= 0; i--)
-		platform_device_unregister(cxl_mem[i]);
+	cxl_single_topo_exit();
 err_dport:
 	for (i = ARRAY_SIZE(cxl_switch_dport) - 1; i >= 0; i--)
 		platform_device_unregister(cxl_switch_dport[i]);
@@ -1486,11 +1503,10 @@ static __exit void cxl_test_exit(void)
 {
 	int i;
 
+	cxl_mem_exit();
 	platform_device_unregister(cxl_acpi);
-	cxl_rch_exit();
-	cxl_single_exit();
-	for (i = ARRAY_SIZE(cxl_mem) - 1; i >= 0; i--)
-		platform_device_unregister(cxl_mem[i]);
+	cxl_rch_topo_exit();
+	cxl_single_topo_exit();
 	for (i = ARRAY_SIZE(cxl_switch_dport) - 1; i >= 0; i--)
 		platform_device_unregister(cxl_switch_dport[i]);
 	for (i = ARRAY_SIZE(cxl_switch_uport) - 1; i >= 0; i--)
diff --git a/tools/testing/cxl/test/mem.c b/tools/testing/cxl/test/mem.c
index ad5c4c18c5c6..71916e0e1546 100644
--- a/tools/testing/cxl/test/mem.c
+++ b/tools/testing/cxl/test/mem.c
@@ -1673,6 +1673,7 @@ static struct platform_driver cxl_mock_mem_driver = {
 		.name = KBUILD_MODNAME,
 		.dev_groups = cxl_mock_mem_groups,
 		.groups = cxl_mock_mem_core_groups,
+		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
 	},
 };