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, 257 insertions, 0 deletions

diff --git a/drivers/ata/libata-trace.c b/drivers/ata/libata-trace.c
new file mode 100644
index 000000000..9b5363fd0
--- /dev/null
+++ b/drivers/ata/libata-trace.c
@@ -0,0 +1,257 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * libata-trace.c - trace functions for libata
+ *
+ * Copyright 2015 Hannes Reinecke
+ * Copyright 2015 SUSE Linux GmbH
+ */
+
+#include <linux/kernel.h>
+#include <linux/trace_seq.h>
+#include <trace/events/libata.h>
+
+const char *
+libata_trace_parse_status(struct trace_seq *p, unsigned char status)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+
+	trace_seq_printf(p, "{ ");
+	if (status & ATA_BUSY)
+		trace_seq_printf(p, "BUSY ");
+	if (status & ATA_DRDY)
+		trace_seq_printf(p, "DRDY ");
+	if (status & ATA_DF)
+		trace_seq_printf(p, "DF ");
+	if (status & ATA_DSC)
+		trace_seq_printf(p, "DSC ");
+	if (status & ATA_DRQ)
+		trace_seq_printf(p, "DRQ ");
+	if (status & ATA_CORR)
+		trace_seq_printf(p, "CORR ");
+	if (status & ATA_SENSE)
+		trace_seq_printf(p, "SENSE ");
+	if (status & ATA_ERR)
+		trace_seq_printf(p, "ERR ");
+	trace_seq_putc(p, '}');
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+const char *
+libata_trace_parse_host_stat(struct trace_seq *p, unsigned char host_stat)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+
+	trace_seq_printf(p, "{ ");
+	if (host_stat & ATA_DMA_INTR)
+		trace_seq_printf(p, "INTR ");
+	if (host_stat & ATA_DMA_ERR)
+		trace_seq_printf(p, "ERR ");
+	if (host_stat & ATA_DMA_ACTIVE)
+		trace_seq_printf(p, "ACTIVE ");
+	trace_seq_putc(p, '}');
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+const char *
+libata_trace_parse_eh_action(struct trace_seq *p, unsigned int eh_action)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+
+	trace_seq_printf(p, "%x", eh_action);
+	if (eh_action) {
+		trace_seq_printf(p, "{ ");
+		if (eh_action & ATA_EH_REVALIDATE)
+			trace_seq_printf(p, "REVALIDATE ");
+		if (eh_action & (ATA_EH_SOFTRESET | ATA_EH_HARDRESET))
+			trace_seq_printf(p, "RESET ");
+		else if (eh_action & ATA_EH_SOFTRESET)
+			trace_seq_printf(p, "SOFTRESET ");
+		else if (eh_action & ATA_EH_HARDRESET)
+			trace_seq_printf(p, "HARDRESET ");
+		if (eh_action & ATA_EH_ENABLE_LINK)
+			trace_seq_printf(p, "ENABLE_LINK ");
+		if (eh_action & ATA_EH_PARK)
+			trace_seq_printf(p, "PARK ");
+		trace_seq_putc(p, '}');
+	}
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+const char *
+libata_trace_parse_eh_err_mask(struct trace_seq *p, unsigned int eh_err_mask)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+
+	trace_seq_printf(p, "%x", eh_err_mask);
+	if (eh_err_mask) {
+		trace_seq_printf(p, "{ ");
+		if (eh_err_mask & AC_ERR_DEV)
+			trace_seq_printf(p, "DEV ");
+		if (eh_err_mask & AC_ERR_HSM)
+			trace_seq_printf(p, "HSM ");
+		if (eh_err_mask & AC_ERR_TIMEOUT)
+			trace_seq_printf(p, "TIMEOUT ");
+		if (eh_err_mask & AC_ERR_MEDIA)
+			trace_seq_printf(p, "MEDIA ");
+		if (eh_err_mask & AC_ERR_ATA_BUS)
+			trace_seq_printf(p, "ATA_BUS ");
+		if (eh_err_mask & AC_ERR_HOST_BUS)
+			trace_seq_printf(p, "HOST_BUS ");
+		if (eh_err_mask & AC_ERR_SYSTEM)
+			trace_seq_printf(p, "SYSTEM ");
+		if (eh_err_mask & AC_ERR_INVALID)
+			trace_seq_printf(p, "INVALID ");
+		if (eh_err_mask & AC_ERR_OTHER)
+			trace_seq_printf(p, "OTHER ");
+		if (eh_err_mask & AC_ERR_NODEV_HINT)
+			trace_seq_printf(p, "NODEV_HINT ");
+		if (eh_err_mask & AC_ERR_NCQ)
+			trace_seq_printf(p, "NCQ ");
+		trace_seq_putc(p, '}');
+	}
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+const char *
+libata_trace_parse_qc_flags(struct trace_seq *p, unsigned int qc_flags)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+
+	trace_seq_printf(p, "%x", qc_flags);
+	if (qc_flags) {
+		trace_seq_printf(p, "{ ");
+		if (qc_flags & ATA_QCFLAG_ACTIVE)
+			trace_seq_printf(p, "ACTIVE ");
+		if (qc_flags & ATA_QCFLAG_DMAMAP)
+			trace_seq_printf(p, "DMAMAP ");
+		if (qc_flags & ATA_QCFLAG_IO)
+			trace_seq_printf(p, "IO ");
+		if (qc_flags & ATA_QCFLAG_RESULT_TF)
+			trace_seq_printf(p, "RESULT_TF ");
+		if (qc_flags & ATA_QCFLAG_CLEAR_EXCL)
+			trace_seq_printf(p, "CLEAR_EXCL ");
+		if (qc_flags & ATA_QCFLAG_QUIET)
+			trace_seq_printf(p, "QUIET ");
+		if (qc_flags & ATA_QCFLAG_RETRY)
+			trace_seq_printf(p, "RETRY ");
+		if (qc_flags & ATA_QCFLAG_EH)
+			trace_seq_printf(p, "FAILED ");
+		if (qc_flags & ATA_QCFLAG_SENSE_VALID)
+			trace_seq_printf(p, "SENSE_VALID ");
+		if (qc_flags & ATA_QCFLAG_EH_SCHEDULED)
+			trace_seq_printf(p, "EH_SCHEDULED ");
+		trace_seq_putc(p, '}');
+	}
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+const char *
+libata_trace_parse_tf_flags(struct trace_seq *p, unsigned int tf_flags)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+
+	trace_seq_printf(p, "%x", tf_flags);
+	if (tf_flags) {
+		trace_seq_printf(p, "{ ");
+		if (tf_flags & ATA_TFLAG_LBA48)
+			trace_seq_printf(p, "LBA48 ");
+		if (tf_flags & ATA_TFLAG_ISADDR)
+			trace_seq_printf(p, "ISADDR ");
+		if (tf_flags & ATA_TFLAG_DEVICE)
+			trace_seq_printf(p, "DEV ");
+		if (tf_flags & ATA_TFLAG_WRITE)
+			trace_seq_printf(p, "WRITE ");
+		if (tf_flags & ATA_TFLAG_LBA)
+			trace_seq_printf(p, "LBA ");
+		if (tf_flags & ATA_TFLAG_FUA)
+			trace_seq_printf(p, "FUA ");
+		if (tf_flags & ATA_TFLAG_POLLING)
+			trace_seq_printf(p, "POLL ");
+		trace_seq_putc(p, '}');
+	}
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+const char *
+libata_trace_parse_subcmd(struct trace_seq *p, unsigned char cmd,
+			  unsigned char feature, unsigned char hob_nsect)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+
+	switch (cmd) {
+	case ATA_CMD_FPDMA_RECV:
+		switch (hob_nsect & 0x5f) {
+		case ATA_SUBCMD_FPDMA_RECV_RD_LOG_DMA_EXT:
+			trace_seq_printf(p, " READ_LOG_DMA_EXT");
+			break;
+		case ATA_SUBCMD_FPDMA_RECV_ZAC_MGMT_IN:
+			trace_seq_printf(p, " ZAC_MGMT_IN");
+			break;
+		}
+		break;
+	case ATA_CMD_FPDMA_SEND:
+		switch (hob_nsect & 0x5f) {
+		case ATA_SUBCMD_FPDMA_SEND_WR_LOG_DMA_EXT:
+			trace_seq_printf(p, " WRITE_LOG_DMA_EXT");
+			break;
+		case ATA_SUBCMD_FPDMA_SEND_DSM:
+			trace_seq_printf(p, " DATASET_MANAGEMENT");
+			break;
+		}
+		break;
+	case ATA_CMD_NCQ_NON_DATA:
+		switch (feature) {
+		case ATA_SUBCMD_NCQ_NON_DATA_ABORT_QUEUE:
+			trace_seq_printf(p, " ABORT_QUEUE");
+			break;
+		case ATA_SUBCMD_NCQ_NON_DATA_SET_FEATURES:
+			trace_seq_printf(p, " SET_FEATURES");
+			break;
+		case ATA_SUBCMD_NCQ_NON_DATA_ZERO_EXT:
+			trace_seq_printf(p, " ZERO_EXT");
+			break;
+		case ATA_SUBCMD_NCQ_NON_DATA_ZAC_MGMT_OUT:
+			trace_seq_printf(p, " ZAC_MGMT_OUT");
+			break;
+		}
+		break;
+	case ATA_CMD_ZAC_MGMT_IN:
+		switch (feature) {
+		case ATA_SUBCMD_ZAC_MGMT_IN_REPORT_ZONES:
+			trace_seq_printf(p, " REPORT_ZONES");
+			break;
+		}
+		break;
+	case ATA_CMD_ZAC_MGMT_OUT:
+		switch (feature) {
+		case ATA_SUBCMD_ZAC_MGMT_OUT_CLOSE_ZONE:
+			trace_seq_printf(p, " CLOSE_ZONE");
+			break;
+		case ATA_SUBCMD_ZAC_MGMT_OUT_FINISH_ZONE:
+			trace_seq_printf(p, " FINISH_ZONE");
+			break;
+		case ATA_SUBCMD_ZAC_MGMT_OUT_OPEN_ZONE:
+			trace_seq_printf(p, " OPEN_ZONE");
+			break;
+		case ATA_SUBCMD_ZAC_MGMT_OUT_RESET_WRITE_POINTER:
+			trace_seq_printf(p, " RESET_WRITE_POINTER");
+			break;
+		}
+		break;
+	}
+	trace_seq_putc(p, 0);
+
+	return ret;
+}