ftrace: Synchronize the initialization of ftrace_opsgrafted

There's some internal state that ftrace_ops needs to have set, but since
it can be declared outside of the ftrace.c code, it calls
ftrace_ops_init() on the ops in every global function. The issue is that
if two tasks call it on the same ops at the same time it is possible to
have the initialization of one corrupt the initialization of the other
call.

Create a ops_mutex to use to synchronize every initialization of the
ftrace_ops. The mutex is taken within checking the ftrace_ops flag that
states it was initializied but the flag is checked again after the mutex
has been taken. Checking first outside the mutex allows it to shortcut
having to take the mutex. But then the check needs to be done again after
the mute is taken in case of races.

Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home
Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock")
Reported-by: sashiko-bot@kernel.org
Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

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;
+}