x86/amd_node: Fix PCI device reference counting in amd_smn_init()grafted

The local "root" pointer is a temporary variable used during the device
search. Therefore, refcount related to the search iterators should be cleaned
up after the search is complete.

Use the __free() cleanup macro to ensure the refcount is decremented when the
temporary pointer goes out of scope.

Additionally, increment the refcount when caching a root pointer. This ensures
the in-use refcount is separate from the temporary search refcounting.

Finally, drop the redundant "root = NULL" before the second search loop. The
pci_get_class() iterator always decrements the refcount of its "from"
argument, so the first loop can only fall through with "root" already NULL.

Fixes: 0a4b61d9c2e4 ("x86/amd_node: Fix AMD root device caching")
Closes: https://sashiko.dev/#/patchset/20260806160159.230453-1-jason.andryuk%40amd.com
Reported-by: Sashiko <sashiko-bot@kernel.org>
Assisted-by: LLM
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Cc: <stable@kernel.org>
Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com

1 files changed, 96 insertions, 0 deletions

diff --git a/drivers/md/dm-vdo/status-codes.c b/drivers/md/dm-vdo/status-codes.c
new file mode 100644
index 000000000..9df5e4d7f
--- /dev/null
+++ b/drivers/md/dm-vdo/status-codes.c
@@ -0,0 +1,96 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2023 Red Hat
+ */
+
+#include "status-codes.h"
+
+#include "errors.h"
+#include "logger.h"
+#include "permassert.h"
+#include "thread-utils.h"
+
+const struct error_info vdo_status_list[] = {
+	{ "VDO_NOT_IMPLEMENTED", "Not implemented" },
+	{ "VDO_OUT_OF_RANGE", "Out of range" },
+	{ "VDO_REF_COUNT_INVALID", "Reference count would become invalid" },
+	{ "VDO_NO_SPACE", "Out of space" },
+	{ "VDO_BAD_CONFIGURATION", "Bad configuration option" },
+	{ "VDO_COMPONENT_BUSY", "Prior operation still in progress" },
+	{ "VDO_BAD_PAGE", "Corrupt or incorrect page" },
+	{ "VDO_UNSUPPORTED_VERSION", "Unsupported component version" },
+	{ "VDO_INCORRECT_COMPONENT", "Component id mismatch in decoder" },
+	{ "VDO_PARAMETER_MISMATCH", "Parameters have conflicting values" },
+	{ "VDO_UNKNOWN_PARTITION", "No partition exists with a given id" },
+	{ "VDO_PARTITION_EXISTS", "A partition already exists with a given id" },
+	{ "VDO_INCREMENT_TOO_SMALL", "Physical block growth of too few blocks" },
+	{ "VDO_CHECKSUM_MISMATCH", "Incorrect checksum" },
+	{ "VDO_LOCK_ERROR", "A lock is held incorrectly" },
+	{ "VDO_READ_ONLY", "The device is in read-only mode" },
+	{ "VDO_SHUTTING_DOWN", "The device is shutting down" },
+	{ "VDO_CORRUPT_JOURNAL", "Recovery journal corrupted" },
+	{ "VDO_TOO_MANY_SLABS", "Exceeds maximum number of slabs supported" },
+	{ "VDO_INVALID_FRAGMENT", "Compressed block fragment is invalid" },
+	{ "VDO_RETRY_AFTER_REBUILD", "Retry operation after rebuilding finishes" },
+	{ "VDO_BAD_MAPPING", "Invalid page mapping" },
+	{ "VDO_BIO_CREATION_FAILED", "Bio creation failed" },
+	{ "VDO_BAD_MAGIC", "Bad magic number" },
+	{ "VDO_BAD_NONCE", "Bad nonce" },
+	{ "VDO_JOURNAL_OVERFLOW", "Journal sequence number overflow" },
+	{ "VDO_INVALID_ADMIN_STATE", "Invalid operation for current state" },
+};
+
+/**
+ * vdo_register_status_codes() - Register the VDO status codes.
+ * Return: A success or error code.
+ */
+int vdo_register_status_codes(void)
+{
+	int result;
+
+	BUILD_BUG_ON((VDO_STATUS_CODE_LAST - VDO_STATUS_CODE_BASE) !=
+		     ARRAY_SIZE(vdo_status_list));
+
+	result = uds_register_error_block("VDO Status", VDO_STATUS_CODE_BASE,
+					  VDO_STATUS_CODE_BLOCK_END, vdo_status_list,
+					  sizeof(vdo_status_list));
+	return (result == UDS_SUCCESS) ? VDO_SUCCESS : result;
+}
+
+/**
+ * vdo_status_to_errno() - Given an error code, return a value we can return to the OS.
+ * @error: The error code to convert.
+ *
+ * The input error code may be a system-generated value (such as -EIO), an errno macro used in our
+ * code (such as EIO), or a UDS or VDO status code; the result must be something the rest of the OS
+ * can consume (negative errno values such as -EIO, in the case of the kernel).
+ *
+ * Return: A system error code value.
+ */
+int vdo_status_to_errno(int error)
+{
+	char error_name[VDO_MAX_ERROR_NAME_SIZE];
+	char error_message[VDO_MAX_ERROR_MESSAGE_SIZE];
+
+	/* 0 is success, negative a system error code */
+	if (likely(error <= 0))
+		return error;
+	if (error < 1024)
+		return -error;
+
+	/* VDO or UDS error */
+	switch (error) {
+	case VDO_BAD_CONFIGURATION:
+		return -EINVAL;
+	case VDO_NO_SPACE:
+		return -ENOSPC;
+	case VDO_READ_ONLY:
+		return -EIO;
+	default:
+		vdo_log_info("%s: mapping internal status code %d (%s: %s) to EIO",
+			     __func__, error,
+			     uds_string_error_name(error, error_name, sizeof(error_name)),
+			     uds_string_error(error, error_message, sizeof(error_message)));
+		return -EIO;
+	}
+}