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/misc/usb3503.c | 460 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 460 insertions(+) create mode 100644 drivers/usb/misc/usb3503.c (limited to 'drivers/usb/misc/usb3503.c') diff --git a/drivers/usb/misc/usb3503.c b/drivers/usb/misc/usb3503.c new file mode 100644 index 000000000..759770a13 --- /dev/null +++ b/drivers/usb/misc/usb3503.c @@ -0,0 +1,460 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Driver for SMSC USB3503 USB 2.0 hub controller driver + * + * Copyright (c) 2012-2013 Dongjin Kim (tobetter@gmail.com) + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define USB3503_VIDL 0x00 +#define USB3503_VIDM 0x01 +#define USB3503_PIDL 0x02 +#define USB3503_PIDM 0x03 +#define USB3503_DIDL 0x04 +#define USB3503_DIDM 0x05 + +#define USB3503_CFG1 0x06 +#define USB3503_SELF_BUS_PWR (1 << 7) + +#define USB3503_CFG2 0x07 +#define USB3503_CFG3 0x08 +#define USB3503_NRD 0x09 + +#define USB3503_PDS 0x0a + +#define USB3503_SP_ILOCK 0xe7 +#define USB3503_SPILOCK_CONNECT (1 << 1) +#define USB3503_SPILOCK_CONFIG (1 << 0) + +#define USB3503_CFGP 0xee +#define USB3503_CLKSUSP (1 << 7) + +#define USB3503_RESET 0xff + +struct usb3503 { + enum usb3503_mode mode; + struct regmap *regmap; + struct device *dev; + struct clk *clk; + u8 port_off_mask; + struct gpio_desc *bypass; + struct gpio_desc *intn; + struct gpio_desc *reset; + struct gpio_desc *connect; + bool secondary_ref_clk; +}; + +static int usb3503_connect(struct usb3503 *hub) +{ + struct device *dev = hub->dev; + int err; + + if (hub->regmap) { + /* SP_ILOCK: set connect_n, config_n for config */ + err = regmap_write(hub->regmap, USB3503_SP_ILOCK, + (USB3503_SPILOCK_CONNECT + | USB3503_SPILOCK_CONFIG)); + if (err < 0) { + dev_err(dev, "SP_ILOCK failed (%d)\n", err); + return err; + } + + /* PDS : Set the ports which are disabled in self-powered mode. */ + if (hub->port_off_mask) { + err = regmap_update_bits(hub->regmap, USB3503_PDS, + hub->port_off_mask, + hub->port_off_mask); + if (err < 0) { + dev_err(dev, "PDS failed (%d)\n", err); + return err; + } + } + + /* CFG1 : Set SELF_BUS_PWR, this enables self-powered operation. */ + err = regmap_update_bits(hub->regmap, USB3503_CFG1, + USB3503_SELF_BUS_PWR, + USB3503_SELF_BUS_PWR); + if (err < 0) { + dev_err(dev, "CFG1 failed (%d)\n", err); + return err; + } + + /* SP_LOCK: clear connect_n, config_n for hub connect */ + err = regmap_update_bits(hub->regmap, USB3503_SP_ILOCK, + (USB3503_SPILOCK_CONNECT + | USB3503_SPILOCK_CONFIG), 0); + if (err < 0) { + dev_err(dev, "SP_ILOCK failed (%d)\n", err); + return err; + } + } + + if (hub->connect) + gpiod_set_value_cansleep(hub->connect, 1); + + hub->mode = USB3503_MODE_HUB; + dev_info(dev, "switched to HUB mode\n"); + + return 0; +} + +static int usb3503_switch_mode(struct usb3503 *hub, enum usb3503_mode mode) +{ + struct device *dev = hub->dev; + int rst, bypass, conn; + + switch (mode) { + case USB3503_MODE_HUB: + conn = 1; + rst = 0; + bypass = 0; + break; + case USB3503_MODE_STANDBY: + conn = 0; + rst = 1; + bypass = 1; + dev_info(dev, "switched to STANDBY mode\n"); + break; + case USB3503_MODE_BYPASS: + conn = 0; + rst = 0; + bypass = 1; + break; + default: + dev_err(dev, "unknown mode is requested\n"); + return -EINVAL; + } + + if (!conn && hub->connect) + gpiod_set_value_cansleep(hub->connect, 0); + + if (hub->reset) + gpiod_set_value_cansleep(hub->reset, rst); + + if (hub->bypass) + gpiod_set_value_cansleep(hub->bypass, bypass); + + if (conn) { + /* Wait T_HUBINIT == 4ms for hub logic to stabilize */ + usleep_range(4000, 10000); + return usb3503_connect(hub); + } + + return 0; +} + +static const struct regmap_config usb3503_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + + .max_register = USB3503_RESET, +}; + +static int usb3503_probe(struct usb3503 *hub) +{ + struct device *dev = hub->dev; + struct usb3503_platform_data *pdata = dev_get_platdata(dev); + struct device_node *np = dev->of_node; + int err; + bool is_clk_enabled = false; + u32 mode = USB3503_MODE_HUB; + const u32 *property; + enum gpiod_flags flags; + int len; + + if (pdata) { + hub->port_off_mask = pdata->port_off_mask; + hub->mode = pdata->initial_mode; + } else if (np) { + u32 rate = 0; + hub->port_off_mask = 0; + + if (!of_property_read_u32(np, "refclk-frequency", &rate)) { + switch (rate) { + case 38400000: + case 26000000: + case 19200000: + case 12000000: + hub->secondary_ref_clk = 0; + break; + case 24000000: + case 27000000: + case 25000000: + case 50000000: + hub->secondary_ref_clk = 1; + break; + default: + dev_err(dev, + "unsupported reference clock rate (%d)\n", + (int) rate); + return -EINVAL; + } + } + + hub->clk = devm_clk_get_optional(dev, "refclk"); + if (IS_ERR(hub->clk)) { + dev_err(dev, "unable to request refclk (%ld)\n", + PTR_ERR(hub->clk)); + return PTR_ERR(hub->clk); + } + + if (rate != 0) { + err = clk_set_rate(hub->clk, rate); + if (err) { + dev_err(dev, + "unable to set reference clock rate to %d\n", + (int)rate); + return err; + } + } + + err = clk_prepare_enable(hub->clk); + if (err) { + dev_err(dev, "unable to enable reference clock\n"); + return err; + } + + is_clk_enabled = true; + property = of_get_property(np, "disabled-ports", &len); + if (property && (len / sizeof(u32)) > 0) { + int i; + for (i = 0; i < len / sizeof(u32); i++) { + u32 port = be32_to_cpu(property[i]); + if ((1 <= port) && (port <= 3)) + hub->port_off_mask |= (1 << port); + } + } + + of_property_read_u32(np, "initial-mode", &mode); + hub->mode = mode; + } + + if (hub->secondary_ref_clk) + flags = GPIOD_OUT_LOW; + else + flags = GPIOD_OUT_HIGH; + hub->intn = devm_gpiod_get_optional(dev, "intn", flags); + if (IS_ERR(hub->intn)) { + err = PTR_ERR(hub->intn); + goto err_clk; + } + if (hub->intn) + gpiod_set_consumer_name(hub->intn, "usb3503 intn"); + + hub->connect = devm_gpiod_get_optional(dev, "connect", GPIOD_OUT_LOW); + if (IS_ERR(hub->connect)) { + err = PTR_ERR(hub->connect); + goto err_clk; + } + if (hub->connect) + gpiod_set_consumer_name(hub->connect, "usb3503 connect"); + + hub->bypass = devm_gpiod_get_optional(dev, "bypass", GPIOD_OUT_HIGH); + if (IS_ERR(hub->bypass)) { + err = PTR_ERR(hub->bypass); + goto err_clk; + } + if (hub->bypass) + gpiod_set_consumer_name(hub->bypass, "usb3503 bypass"); + + hub->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH); + if (IS_ERR(hub->reset)) { + err = PTR_ERR(hub->reset); + goto err_clk; + } + if (hub->reset) { + /* Datasheet defines a hardware reset to be at least 100us */ + usleep_range(100, 10000); + gpiod_set_consumer_name(hub->reset, "usb3503 reset"); + } + + if (hub->port_off_mask && !hub->regmap) + dev_err(dev, "Ports disabled with no control interface\n"); + + usb3503_switch_mode(hub, hub->mode); + + dev_info(dev, "%s: probed in %s mode\n", __func__, + (hub->mode == USB3503_MODE_HUB) ? "hub" : "standby"); + + return 0; + +err_clk: + if (is_clk_enabled) + clk_disable_unprepare(hub->clk); + return err; +} + +static int usb3503_i2c_probe(struct i2c_client *i2c) +{ + struct usb3503 *hub; + int err; + + hub = devm_kzalloc(&i2c->dev, sizeof(struct usb3503), GFP_KERNEL); + if (!hub) + return -ENOMEM; + + i2c_set_clientdata(i2c, hub); + hub->regmap = devm_regmap_init_i2c(i2c, &usb3503_regmap_config); + if (IS_ERR(hub->regmap)) { + err = PTR_ERR(hub->regmap); + dev_err(&i2c->dev, "Failed to initialise regmap: %d\n", err); + return err; + } + hub->dev = &i2c->dev; + + return usb3503_probe(hub); +} + +static void usb3503_i2c_remove(struct i2c_client *i2c) +{ + struct usb3503 *hub; + + hub = i2c_get_clientdata(i2c); + clk_disable_unprepare(hub->clk); +} + +static int usb3503_platform_probe(struct platform_device *pdev) +{ + struct usb3503 *hub; + + hub = devm_kzalloc(&pdev->dev, sizeof(struct usb3503), GFP_KERNEL); + if (!hub) + return -ENOMEM; + hub->dev = &pdev->dev; + platform_set_drvdata(pdev, hub); + + return usb3503_probe(hub); +} + +static void usb3503_platform_remove(struct platform_device *pdev) +{ + struct usb3503 *hub; + + hub = platform_get_drvdata(pdev); + clk_disable_unprepare(hub->clk); +} + +static int __maybe_unused usb3503_suspend(struct usb3503 *hub) +{ + usb3503_switch_mode(hub, USB3503_MODE_STANDBY); + clk_disable_unprepare(hub->clk); + + return 0; +} + +static int __maybe_unused usb3503_resume(struct usb3503 *hub) +{ + clk_prepare_enable(hub->clk); + usb3503_switch_mode(hub, hub->mode); + + return 0; +} + +static int __maybe_unused usb3503_i2c_suspend(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + + return usb3503_suspend(i2c_get_clientdata(client)); +} + +static int __maybe_unused usb3503_i2c_resume(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + + return usb3503_resume(i2c_get_clientdata(client)); +} + +static int __maybe_unused usb3503_platform_suspend(struct device *dev) +{ + return usb3503_suspend(dev_get_drvdata(dev)); +} + +static int __maybe_unused usb3503_platform_resume(struct device *dev) +{ + return usb3503_resume(dev_get_drvdata(dev)); +} + +static SIMPLE_DEV_PM_OPS(usb3503_i2c_pm_ops, usb3503_i2c_suspend, + usb3503_i2c_resume); + +static SIMPLE_DEV_PM_OPS(usb3503_platform_pm_ops, usb3503_platform_suspend, + usb3503_platform_resume); + +static const struct i2c_device_id usb3503_id[] = { + { .name = USB3503_I2C_NAME }, + { } +}; +MODULE_DEVICE_TABLE(i2c, usb3503_id); + +#ifdef CONFIG_OF +static const struct of_device_id usb3503_of_match[] = { + { .compatible = "smsc,usb3503", }, + { .compatible = "smsc,usb3503a", }, + { .compatible = "smsc,usb3803", }, + {}, +}; +MODULE_DEVICE_TABLE(of, usb3503_of_match); +#endif + +static struct i2c_driver usb3503_i2c_driver = { + .driver = { + .name = USB3503_I2C_NAME, + .pm = pm_ptr(&usb3503_i2c_pm_ops), + .of_match_table = of_match_ptr(usb3503_of_match), + }, + .probe = usb3503_i2c_probe, + .remove = usb3503_i2c_remove, + .id_table = usb3503_id, +}; + +static struct platform_driver usb3503_platform_driver = { + .driver = { + .name = USB3503_I2C_NAME, + .of_match_table = of_match_ptr(usb3503_of_match), + .pm = pm_ptr(&usb3503_platform_pm_ops), + }, + .probe = usb3503_platform_probe, + .remove = usb3503_platform_remove, +}; + +static int __init usb3503_init(void) +{ + int err; + + err = i2c_add_driver(&usb3503_i2c_driver); + if (err) { + pr_err("usb3503: Failed to register I2C driver: %d\n", err); + return err; + } + + err = platform_driver_register(&usb3503_platform_driver); + if (err) { + pr_err("usb3503: Failed to register platform driver: %d\n", + err); + i2c_del_driver(&usb3503_i2c_driver); + return err; + } + + return 0; +} +module_init(usb3503_init); + +static void __exit usb3503_exit(void) +{ + platform_driver_unregister(&usb3503_platform_driver); + i2c_del_driver(&usb3503_i2c_driver); +} +module_exit(usb3503_exit); + +MODULE_AUTHOR("Dongjin Kim "); +MODULE_DESCRIPTION("USB3503 USB HUB driver"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1