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

2 files changed, 78 insertions, 0 deletions

diff --git a/include/uapi/misc/uacce/hisi_qm.h b/include/uapi/misc/uacce/hisi_qm.h
new file mode 100644
index 000000000..10504b48e
--- /dev/null
+++ b/include/uapi/misc/uacce/hisi_qm.h
@@ -0,0 +1,40 @@
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+#ifndef _UAPI_HISI_QM_H
+#define _UAPI_HISI_QM_H
+
+#include <linux/types.h>
+
+/**
+ * struct hisi_qp_ctx - User data for hisi qp.
+ * @id: qp_index return to user space
+ * @qc_type: Accelerator algorithm type
+ */
+struct hisi_qp_ctx {
+	__u16 id;
+	__u16 qc_type;
+};
+
+/**
+ * struct hisi_qp_info - User data for hisi qp.
+ * @sqe_size: Submission queue element size
+ * @sq_depth: The number of sqe
+ * @cq_depth: The number of cqe
+ * @reserved: Reserved data
+ */
+struct hisi_qp_info {
+	__u32 sqe_size;
+	__u16 sq_depth;
+	__u16 cq_depth;
+	__u64 reserved;
+};
+
+#define HISI_QM_API_VER_BASE "hisi_qm_v1"
+#define HISI_QM_API_VER2_BASE "hisi_qm_v2"
+#define HISI_QM_API_VER3_BASE "hisi_qm_v3"
+#define HISI_QM_API_VER5_BASE "hisi_qm_v5"
+
+/* UACCE_CMD_QM_SET_QP_CTX: Set qp algorithm type */
+#define UACCE_CMD_QM_SET_QP_CTX	_IOWR('H', 10, struct hisi_qp_ctx)
+/* UACCE_CMD_QM_SET_QP_INFO: Set qp depth and BD size */
+#define UACCE_CMD_QM_SET_QP_INFO _IOWR('H', 11, struct hisi_qp_info)
+#endif
diff --git a/include/uapi/misc/uacce/uacce.h b/include/uapi/misc/uacce/uacce.h
new file mode 100644
index 000000000..cc7185678
--- /dev/null
+++ b/include/uapi/misc/uacce/uacce.h
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+#ifndef _UAPIUUACCE_H
+#define _UAPIUUACCE_H
+
+#include <linux/types.h>
+#include <linux/ioctl.h>
+
+/*
+ * UACCE_CMD_START_Q: Start queue
+ */
+#define UACCE_CMD_START_Q	_IO('W', 0)
+
+/*
+ * UACCE_CMD_PUT_Q:
+ * User actively stop queue and free queue resource immediately
+ * Optimization method since close fd may delay
+ */
+#define UACCE_CMD_PUT_Q		_IO('W', 1)
+
+/*
+ * UACCE Device flags:
+ * UACCE_DEV_SVA: Shared Virtual Addresses
+ *		  Support PASID
+ *		  Support device page faults (PCI PRI or SMMU Stall)
+ */
+#define UACCE_DEV_SVA		BIT(0)
+
+/**
+ * enum uacce_qfrt: queue file region type
+ * @UACCE_QFRT_MMIO: device mmio region
+ * @UACCE_QFRT_DUS: device user share region
+ */
+enum uacce_qfrt {
+	UACCE_QFRT_MMIO = 0,
+	UACCE_QFRT_DUS = 1,
+};
+
+#endif