From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops 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 --- drivers/crypto/ccp/sp-dev.c | 325 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 325 insertions(+) create mode 100644 drivers/crypto/ccp/sp-dev.c (limited to 'drivers/crypto/ccp/sp-dev.c') diff --git a/drivers/crypto/ccp/sp-dev.c b/drivers/crypto/ccp/sp-dev.c new file mode 100644 index 000000000..f204aa5df --- /dev/null +++ b/drivers/crypto/ccp/sp-dev.c @@ -0,0 +1,325 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * AMD Secure Processor driver + * + * Copyright (C) 2017-2018 Advanced Micro Devices, Inc. + * + * Author: Tom Lendacky + * Author: Gary R Hook + * Author: Brijesh Singh + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "sev-dev.h" +#include "ccp-dev.h" +#include "sp-dev.h" + +MODULE_AUTHOR("Tom Lendacky "); +MODULE_AUTHOR("Gary R Hook "); +MODULE_LICENSE("GPL"); +MODULE_VERSION("1.1.0"); +MODULE_DESCRIPTION("AMD Secure Processor driver"); + +/* List of SPs, SP count, read-write access lock, and access functions + * + * Lock structure: get sp_unit_lock for reading whenever we need to + * examine the SP list. + */ +static DEFINE_RWLOCK(sp_unit_lock); +static LIST_HEAD(sp_units); + +/* Ever-increasing value to produce unique unit numbers */ +static atomic_t sp_ordinal; + +static void sp_add_device(struct sp_device *sp) +{ + unsigned long flags; + + write_lock_irqsave(&sp_unit_lock, flags); + + list_add_tail(&sp->entry, &sp_units); + + write_unlock_irqrestore(&sp_unit_lock, flags); +} + +static void sp_del_device(struct sp_device *sp) +{ + unsigned long flags; + + write_lock_irqsave(&sp_unit_lock, flags); + + list_del(&sp->entry); + + write_unlock_irqrestore(&sp_unit_lock, flags); +} + +static irqreturn_t sp_irq_handler(int irq, void *data) +{ + struct sp_device *sp = data; + + if (sp->ccp_irq_handler) + sp->ccp_irq_handler(irq, sp->ccp_irq_data); + + if (sp->psp_irq_handler) + sp->psp_irq_handler(irq, sp->psp_irq_data); + + return IRQ_HANDLED; +} + +int sp_request_ccp_irq(struct sp_device *sp, irq_handler_t handler, + const char *name, void *data) +{ + int ret; + + if ((sp->psp_irq == sp->ccp_irq) && sp->dev_vdata->psp_vdata) { + /* Need a common routine to manage all interrupts */ + sp->ccp_irq_data = data; + sp->ccp_irq_handler = handler; + + if (!sp->irq_registered) { + ret = request_irq(sp->ccp_irq, sp_irq_handler, 0, + sp->name, sp); + if (ret) + return ret; + + sp->irq_registered = true; + } + } else { + /* Each sub-device can manage it's own interrupt */ + ret = request_irq(sp->ccp_irq, handler, 0, name, data); + if (ret) + return ret; + } + + return 0; +} + +int sp_request_psp_irq(struct sp_device *sp, irq_handler_t handler, + const char *name, void *data) +{ + int ret; + + if ((sp->psp_irq == sp->ccp_irq) && sp->dev_vdata->ccp_vdata) { + /* Need a common routine to manage all interrupts */ + sp->psp_irq_data = data; + sp->psp_irq_handler = handler; + + if (!sp->irq_registered) { + ret = request_irq(sp->psp_irq, sp_irq_handler, 0, + sp->name, sp); + if (ret) + return ret; + + sp->irq_registered = true; + } + } else { + /* Each sub-device can manage it's own interrupt */ + ret = request_irq(sp->psp_irq, handler, 0, name, data); + if (ret) + return ret; + } + + return 0; +} + +void sp_free_ccp_irq(struct sp_device *sp, void *data) +{ + if ((sp->psp_irq == sp->ccp_irq) && sp->dev_vdata->psp_vdata) { + /* Using common routine to manage all interrupts */ + if (!sp->psp_irq_handler) { + /* Nothing else using it, so free it */ + free_irq(sp->ccp_irq, sp); + + sp->irq_registered = false; + } + + sp->ccp_irq_handler = NULL; + sp->ccp_irq_data = NULL; + } else { + /* Each sub-device can manage it's own interrupt */ + free_irq(sp->ccp_irq, data); + } +} + +void sp_free_psp_irq(struct sp_device *sp, void *data) +{ + if ((sp->psp_irq == sp->ccp_irq) && sp->dev_vdata->ccp_vdata) { + /* Using common routine to manage all interrupts */ + if (!sp->ccp_irq_handler) { + /* Nothing else using it, so free it */ + free_irq(sp->psp_irq, sp); + + sp->irq_registered = false; + } + + sp->psp_irq_handler = NULL; + sp->psp_irq_data = NULL; + } else { + /* Each sub-device can manage it's own interrupt */ + free_irq(sp->psp_irq, data); + } +} + +/** + * sp_alloc_struct - allocate and initialize the sp_device struct + * + * @dev: device struct of the SP + */ +struct sp_device *sp_alloc_struct(struct device *dev) +{ + struct sp_device *sp; + + sp = devm_kzalloc(dev, sizeof(*sp), GFP_KERNEL); + if (!sp) + return NULL; + + sp->dev = dev; + sp->ord = atomic_inc_return(&sp_ordinal); + snprintf(sp->name, SP_MAX_NAME_LEN, "sp-%u", sp->ord); + + return sp; +} + +int sp_init(struct sp_device *sp) +{ + sp_add_device(sp); + + if (sp->dev_vdata->ccp_vdata) + ccp_dev_init(sp); + + if (sp->dev_vdata->psp_vdata) + psp_dev_init(sp); + return 0; +} + +void sp_destroy(struct sp_device *sp) +{ + if (sp->dev_vdata->ccp_vdata) + ccp_dev_destroy(sp); + + if (sp->dev_vdata->psp_vdata) + psp_dev_destroy(sp); + + sp_del_device(sp); +} + +int sp_suspend(struct sp_device *sp) +{ + if (sp->dev_vdata->ccp_vdata) { + ccp_dev_suspend(sp); + } + + return 0; +} + +int sp_resume(struct sp_device *sp) +{ + if (sp->dev_vdata->ccp_vdata) { + ccp_dev_resume(sp); + } + + return 0; +} + +int sp_restore(struct sp_device *sp) +{ + if (sp->psp_data) { + int ret = psp_restore(sp); + + if (ret) + return ret; + } + + return sp_resume(sp); +} + +struct sp_device *sp_get_psp_master_device(void) +{ + struct sp_device *i, *ret = NULL; + unsigned long flags; + + write_lock_irqsave(&sp_unit_lock, flags); + if (list_empty(&sp_units)) + goto unlock; + + list_for_each_entry(i, &sp_units, entry) { + if (i->psp_data && i->get_psp_master_device) { + ret = i->get_psp_master_device(); + break; + } + } + +unlock: + write_unlock_irqrestore(&sp_unit_lock, flags); + return ret; +} + +static int __init sp_mod_init(void) +{ +#ifdef CONFIG_X86 + static bool initialized; + int ret; + + if (initialized) + return 0; + + ret = sp_pci_init(); + if (ret) + return ret; + +#ifdef CONFIG_CRYPTO_DEV_SP_PSP + psp_pci_init(); +#endif + + initialized = true; + + return 0; +#endif + +#ifdef CONFIG_ARM64 + int ret; + + ret = sp_platform_init(); + if (ret) + return ret; + + return 0; +#endif + + return -ENODEV; +} + +#if IS_BUILTIN(CONFIG_KVM_AMD) && IS_ENABLED(CONFIG_KVM_AMD_SEV) +int __init sev_module_init(void) +{ + return sp_mod_init(); +} +#endif + +static void __exit sp_mod_exit(void) +{ +#ifdef CONFIG_X86 + +#ifdef CONFIG_CRYPTO_DEV_SP_PSP + psp_pci_exit(); +#endif + + sp_pci_exit(); +#endif + +#ifdef CONFIG_ARM64 + sp_platform_exit(); +#endif +} + +module_init(sp_mod_init); +module_exit(sp_mod_exit); -- cgit v1.3.1