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, 89 insertions, 0 deletions

diff --git a/drivers/crypto/ccp/sev-dev.h b/drivers/crypto/ccp/sev-dev.h
new file mode 100644
index 000000000..d5e596606
--- /dev/null
+++ b/drivers/crypto/ccp/sev-dev.h
@@ -0,0 +1,89 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * AMD Platform Security Processor (PSP) interface driver
+ *
+ * Copyright (C) 2017-2019 Advanced Micro Devices, Inc.
+ *
+ * Author: Brijesh Singh <brijesh.singh@amd.com>
+ */
+
+#ifndef __SEV_DEV_H__
+#define __SEV_DEV_H__
+
+#include <linux/device.h>
+#include <linux/spinlock.h>
+#include <linux/mutex.h>
+#include <linux/list.h>
+#include <linux/wait.h>
+#include <linux/dmapool.h>
+#include <linux/hw_random.h>
+#include <linux/bitops.h>
+#include <linux/interrupt.h>
+#include <linux/irqreturn.h>
+#include <linux/dmaengine.h>
+#include <linux/psp-sev.h>
+#include <linux/miscdevice.h>
+#include <linux/capability.h>
+
+#define SEV_CMDRESP_CMD			GENMASK(26, 16)
+#define SEV_CMD_COMPLETE		BIT(1)
+#define SEV_CMDRESP_IOC			BIT(0)
+
+struct sev_misc_dev {
+	struct kref refcount;
+	struct miscdevice misc;
+};
+
+struct sev_tio_status;
+
+struct sev_device {
+	struct device *dev;
+	struct psp_device *psp;
+
+	void __iomem *io_regs;
+
+	struct sev_vdata *vdata;
+
+	unsigned int int_rcvd;
+	wait_queue_head_t int_queue;
+	struct sev_misc_dev *misc;
+
+	u8 api_major;
+	u8 api_minor;
+	u8 build;
+
+	void *cmd_buf;
+	void *cmd_buf_backup;
+	bool cmd_buf_active;
+	bool cmd_buf_backup_active;
+
+	bool snp_initialized;
+
+	struct kobject *sev_kobj;
+	struct kobject *verify_mit;
+
+	struct sev_user_data_status sev_plat_status;
+
+	struct sev_user_data_snp_status snp_plat_status;
+	struct snp_feature_info snp_feat_info_0;
+
+	struct tsm_dev *tsmdev;
+	struct sev_tio_status *tio_status;
+};
+
+int sev_dev_init(struct psp_device *psp);
+void sev_dev_destroy(struct psp_device *psp);
+
+int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret);
+
+void sev_pci_init(void);
+void sev_pci_exit(void);
+
+struct page *snp_alloc_hv_fixed_pages(unsigned int num_2mb_pages);
+void snp_free_hv_fixed_pages(struct page *page);
+
+void sev_tsm_init_locked(struct sev_device *sev, void *tio_status_page);
+void sev_tsm_uninit(struct sev_device *sev);
+int sev_tio_cmd_buffer_len(int cmd);
+
+#endif /* __SEV_DEV_H */