From 93de2a6a4b91b72607136dd656edf03fb399d27f Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Wed, 23 Sep 2026 09:37:21 -0700 Subject: KVM: SEV: Do cache maintenance on the source VM during intra-host migration Manually perform cache maintenance on the source VM during intra-host migration to ensure no stale data is left in CPU caches after the VM is destroyed. Because the source VM is "converted" to a non-SEV VM, KVM's memory reclaim flows won't trigger cache maintenance, e.g. when all guest memory is reclaimed in response to detaching from the mmu_notifier. Note, relying on the destination VM to do cache maintenance isn't an option as KVM doesn't require identical guest memory configurations, i.e. the source VM may have access to memory that the destination VM does not. Enforcing equivalent memory configurations is infeasible, as it would require a *deep* comparison of memslots, e.g. to verify that not only are the memslot identical, but what the memslots point at is also identical. Fixes: b56639318bb2 ("KVM: SEV: Add support for SEV intra host migration") Cc: stable@vger.kernel.org Reported-by: Stefan Teodorescu Signed-off-by: Sean Christopherson Message-ID: <20260923163721.1584779-3-seanjc@google.com> Signed-off-by: Paolo Bonzini --- drivers/usb/phy/phy-generic.c | 348 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 348 insertions(+) create mode 100644 drivers/usb/phy/phy-generic.c (limited to 'drivers/usb/phy/phy-generic.c') diff --git a/drivers/usb/phy/phy-generic.c b/drivers/usb/phy/phy-generic.c new file mode 100644 index 000000000..de26b3023 --- /dev/null +++ b/drivers/usb/phy/phy-generic.c @@ -0,0 +1,348 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * NOP USB transceiver for all USB transceiver which are either built-in + * into USB IP or which are mostly autonomous. + * + * Copyright (C) 2009 Texas Instruments Inc + * Author: Ajay Kumar Gupta + * + * Current status: + * This provides a "nop" transceiver for PHYs which are + * autonomous such as isp1504, isp1707, etc. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "phy-generic.h" + +#define VBUS_IRQ_FLAGS \ + (IRQF_SHARED | IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | \ + IRQF_ONESHOT) + +struct platform_device *usb_phy_generic_register(void) +{ + return platform_device_register_simple("usb_phy_generic", + PLATFORM_DEVID_AUTO, NULL, 0); +} +EXPORT_SYMBOL_GPL(usb_phy_generic_register); + +void usb_phy_generic_unregister(struct platform_device *pdev) +{ + platform_device_unregister(pdev); +} +EXPORT_SYMBOL_GPL(usb_phy_generic_unregister); + +static int nop_set_suspend(struct usb_phy *x, int suspend) +{ + struct usb_phy_generic *nop = dev_get_drvdata(x->dev); + int ret = 0; + + if (suspend) { + clk_disable_unprepare(nop->clk); + if (!IS_ERR(nop->vcc) && !device_may_wakeup(x->dev)) + ret = regulator_disable(nop->vcc); + } else { + if (!IS_ERR(nop->vcc) && !device_may_wakeup(x->dev)) + ret = regulator_enable(nop->vcc); + clk_prepare_enable(nop->clk); + } + + return ret; +} + +static void nop_reset(struct usb_phy_generic *nop) +{ + if (!nop->gpiod_reset) + return; + + gpiod_set_value_cansleep(nop->gpiod_reset, 1); + usleep_range(10000, 20000); + gpiod_set_value_cansleep(nop->gpiod_reset, 0); + usleep_range(10000, 30000); +} + +/* interface to regulator framework */ +static int nop_set_vbus(struct usb_otg *otg, bool enable) +{ + int ret = 0; + struct usb_phy_generic *nop = dev_get_drvdata(otg->usb_phy->dev); + + if (!nop->vbus_draw) + return 0; + + if (enable && !nop->vbus_draw_enabled) { + ret = regulator_enable(nop->vbus_draw); + if (ret) + nop->vbus_draw_enabled = false; + else + nop->vbus_draw_enabled = true; + + } else if (!enable && nop->vbus_draw_enabled) { + ret = regulator_disable(nop->vbus_draw); + nop->vbus_draw_enabled = false; + } + return ret; +} + + +static irqreturn_t nop_gpio_vbus_thread(int irq, void *data) +{ + struct usb_phy_generic *nop = data; + struct usb_otg *otg = nop->phy.otg; + int vbus, status; + + vbus = gpiod_get_value(nop->gpiod_vbus); + if ((vbus ^ nop->vbus) == 0) + return IRQ_HANDLED; + nop->vbus = vbus; + + if (vbus) { + status = USB_EVENT_VBUS; + otg->state = OTG_STATE_B_PERIPHERAL; + nop->phy.last_event = status; + + atomic_notifier_call_chain(&nop->phy.notifier, status, + otg->gadget); + } else { + status = USB_EVENT_NONE; + otg->state = OTG_STATE_B_IDLE; + nop->phy.last_event = status; + + atomic_notifier_call_chain(&nop->phy.notifier, status, + otg->gadget); + } + return IRQ_HANDLED; +} + +int usb_gen_phy_init(struct usb_phy *phy) +{ + struct usb_phy_generic *nop = dev_get_drvdata(phy->dev); + int ret; + + if (!IS_ERR(nop->vcc)) { + if (regulator_enable(nop->vcc)) + dev_err(phy->dev, "Failed to enable power\n"); + } + + ret = clk_prepare_enable(nop->clk); + if (ret) + return ret; + + nop_reset(nop); + + return 0; +} +EXPORT_SYMBOL_GPL(usb_gen_phy_init); + +void usb_gen_phy_shutdown(struct usb_phy *phy) +{ + struct usb_phy_generic *nop = dev_get_drvdata(phy->dev); + + gpiod_set_value_cansleep(nop->gpiod_reset, 1); + + clk_disable_unprepare(nop->clk); + + if (!IS_ERR(nop->vcc)) { + if (regulator_disable(nop->vcc)) + dev_err(phy->dev, "Failed to disable power\n"); + } +} +EXPORT_SYMBOL_GPL(usb_gen_phy_shutdown); + +static int nop_set_peripheral(struct usb_otg *otg, struct usb_gadget *gadget) +{ + if (!otg) + return -ENODEV; + + if (!gadget) { + otg->gadget = NULL; + return -ENODEV; + } + + otg->gadget = gadget; + if (otg->state == OTG_STATE_B_PERIPHERAL) + atomic_notifier_call_chain(&otg->usb_phy->notifier, + USB_EVENT_VBUS, otg->gadget); + else + otg->state = OTG_STATE_B_IDLE; + return 0; +} + +static int nop_set_host(struct usb_otg *otg, struct usb_bus *host) +{ + if (!otg) + return -ENODEV; + + if (!host) { + otg->host = NULL; + return -ENODEV; + } + + otg->host = host; + return 0; +} + +int usb_phy_gen_create_phy(struct device *dev, struct usb_phy_generic *nop) +{ + enum usb_phy_type type = USB_PHY_TYPE_USB2; + int err = 0; + u32 clk_rate = 0; + + device_property_read_u32(dev, "clock-frequency", &clk_rate); + nop->gpiod_reset = devm_gpiod_get_optional(dev, "reset", + GPIOD_ASIS); + err = PTR_ERR_OR_ZERO(nop->gpiod_reset); + if (!err) { + nop->gpiod_vbus = devm_gpiod_get_optional(dev, + "vbus-detect", + GPIOD_ASIS); + err = PTR_ERR_OR_ZERO(nop->gpiod_vbus); + } + + if (err) + return dev_err_probe(dev, err, + "Error requesting RESET or VBUS GPIO\n"); + if (nop->gpiod_reset) + gpiod_direction_output(nop->gpiod_reset, 1); + + nop->phy.otg = devm_kzalloc(dev, sizeof(*nop->phy.otg), + GFP_KERNEL); + if (!nop->phy.otg) + return -ENOMEM; + + nop->clk = devm_clk_get_optional(dev, "main_clk"); + if (IS_ERR(nop->clk)) + return dev_err_probe(dev, PTR_ERR(nop->clk), + "Can't get phy clock\n"); + + if (clk_rate) { + err = clk_set_rate(nop->clk, clk_rate); + if (err) + return dev_err_probe(dev, err, + "Error setting clock rate\n"); + } + + nop->vcc = devm_regulator_get_optional(dev, "vcc"); + if (IS_ERR(nop->vcc) && PTR_ERR(nop->vcc) != -ENODEV) + return dev_err_probe(dev, PTR_ERR(nop->vcc), + "could not get vcc regulator\n"); + + nop->vbus_draw = devm_regulator_get_exclusive(dev, "vbus"); + if (PTR_ERR(nop->vbus_draw) == -ENODEV) + nop->vbus_draw = NULL; + if (IS_ERR(nop->vbus_draw)) + return dev_err_probe(dev, PTR_ERR(nop->vbus_draw), + "could not get vbus regulator\n"); + + nop->dev = dev; + nop->phy.dev = nop->dev; + nop->phy.label = "nop-xceiv"; + nop->phy.set_suspend = nop_set_suspend; + nop->phy.type = type; + + nop->phy.otg->state = OTG_STATE_UNDEFINED; + nop->phy.otg->usb_phy = &nop->phy; + nop->phy.otg->set_host = nop_set_host; + nop->phy.otg->set_peripheral = nop_set_peripheral; + nop->phy.otg->set_vbus = nop_set_vbus; + + return 0; +} +EXPORT_SYMBOL_GPL(usb_phy_gen_create_phy); + +static int usb_phy_generic_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct usb_phy_generic *nop; + int err; + + nop = devm_kzalloc(dev, sizeof(*nop), GFP_KERNEL); + if (!nop) + return -ENOMEM; + + err = usb_phy_gen_create_phy(dev, nop); + if (err) + return err; + + if (nop->gpiod_vbus) { + err = devm_request_threaded_irq(dev, + gpiod_to_irq(nop->gpiod_vbus), + NULL, nop_gpio_vbus_thread, + VBUS_IRQ_FLAGS, "vbus_detect", + nop); + if (err) + return dev_err_probe(dev, err, "can't request irq %i\n", + gpiod_to_irq(nop->gpiod_vbus)); + + nop->phy.otg->state = gpiod_get_value(nop->gpiod_vbus) ? + OTG_STATE_B_PERIPHERAL : OTG_STATE_B_IDLE; + } + + nop->phy.init = usb_gen_phy_init; + nop->phy.shutdown = usb_gen_phy_shutdown; + + err = usb_add_phy_dev(&nop->phy); + if (err) + return dev_err_probe(dev, err, "can't register transceiver\n"); + + platform_set_drvdata(pdev, nop); + + device_set_wakeup_capable(dev, + device_property_read_bool(dev, "wakeup-source")); + + return 0; +} + +static void usb_phy_generic_remove(struct platform_device *pdev) +{ + struct usb_phy_generic *nop = platform_get_drvdata(pdev); + + usb_remove_phy(&nop->phy); + + if (nop->vbus_draw && nop->vbus_draw_enabled) + regulator_disable(nop->vbus_draw); +} + +static const struct of_device_id nop_xceiv_dt_ids[] = { + { .compatible = "usb-nop-xceiv" }, + { } +}; + +MODULE_DEVICE_TABLE(of, nop_xceiv_dt_ids); + +static struct platform_driver usb_phy_generic_driver = { + .probe = usb_phy_generic_probe, + .remove = usb_phy_generic_remove, + .driver = { + .name = "usb_phy_generic", + .of_match_table = nop_xceiv_dt_ids, + }, +}; + +static int __init usb_phy_generic_init(void) +{ + return platform_driver_register(&usb_phy_generic_driver); +} +subsys_initcall(usb_phy_generic_init); + +static void __exit usb_phy_generic_exit(void) +{ + platform_driver_unregister(&usb_phy_generic_driver); +} +module_exit(usb_phy_generic_exit); + +MODULE_ALIAS("platform:usb_phy_generic"); +MODULE_AUTHOR("Texas Instruments Inc"); +MODULE_DESCRIPTION("NOP USB Transceiver driver"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1