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/gpio/gpio-syscon.c | 272 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 272 insertions(+) create mode 100644 drivers/gpio/gpio-syscon.c (limited to 'drivers/gpio/gpio-syscon.c') diff --git a/drivers/gpio/gpio-syscon.c b/drivers/gpio/gpio-syscon.c new file mode 100644 index 000000000..40064d4cf --- /dev/null +++ b/drivers/gpio/gpio-syscon.c @@ -0,0 +1,272 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * SYSCON GPIO driver + * + * Copyright (C) 2014 Alexander Shiyan + */ + +#include +#include +#include +#include +#include +#include +#include + +#define GPIO_SYSCON_FEAT_IN BIT(0) +#define GPIO_SYSCON_FEAT_OUT BIT(1) +#define GPIO_SYSCON_FEAT_DIR BIT(2) + +/* SYSCON driver is designed to use 32-bit wide registers */ +#define SYSCON_REG_SIZE (4) +#define SYSCON_REG_BITS (SYSCON_REG_SIZE * 8) + +/** + * struct syscon_gpio_data - Configuration for the device. + * @flags: Set of GPIO_SYSCON_FEAT_ flags: + * GPIO_SYSCON_FEAT_IN: GPIOs supports input, + * GPIO_SYSCON_FEAT_OUT: GPIOs supports output, + * GPIO_SYSCON_FEAT_DIR: GPIOs supports switch direction. + * @bit_count: Number of bits used as GPIOs. + * @dat_bit_offset: Offset (in bits) to the first GPIO bit. + * @dir_bit_offset: Optional offset (in bits) to the first bit to switch + * GPIO direction (Used with GPIO_SYSCON_FEAT_DIR flag). + * @set: HW specific callback to assigns output value + * for signal "offset" + */ + +struct syscon_gpio_data { + unsigned int flags; + unsigned int bit_count; + unsigned int dat_bit_offset; + unsigned int dir_bit_offset; + int (*set)(struct gpio_chip *chip, unsigned int offset, + int value); +}; + +struct syscon_gpio_priv { + struct gpio_chip chip; + struct regmap *syscon; + const struct syscon_gpio_data *data; + u32 dreg_offset; + u32 dir_reg_offset; +}; + +static int syscon_gpio_get(struct gpio_chip *chip, unsigned offset) +{ + struct syscon_gpio_priv *priv = gpiochip_get_data(chip); + unsigned int val, offs; + int ret; + + offs = priv->dreg_offset + priv->data->dat_bit_offset + offset; + + ret = regmap_read(priv->syscon, + (offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE, &val); + if (ret) + return ret; + + return !!(val & BIT(offs % SYSCON_REG_BITS)); +} + +static int syscon_gpio_set(struct gpio_chip *chip, unsigned int offset, int val) +{ + struct syscon_gpio_priv *priv = gpiochip_get_data(chip); + unsigned int offs; + + offs = priv->dreg_offset + priv->data->dat_bit_offset + offset; + + return regmap_update_bits(priv->syscon, + (offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE, + BIT(offs % SYSCON_REG_BITS), + val ? BIT(offs % SYSCON_REG_BITS) : 0); +} + +static int syscon_gpio_dir_in(struct gpio_chip *chip, unsigned offset) +{ + struct syscon_gpio_priv *priv = gpiochip_get_data(chip); + + if (priv->data->flags & GPIO_SYSCON_FEAT_DIR) { + unsigned int offs; + + offs = priv->dir_reg_offset + + priv->data->dir_bit_offset + offset; + + regmap_update_bits(priv->syscon, + (offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE, + BIT(offs % SYSCON_REG_BITS), 0); + } + + return 0; +} + +static int syscon_gpio_dir_out(struct gpio_chip *chip, unsigned offset, int val) +{ + struct syscon_gpio_priv *priv = gpiochip_get_data(chip); + + if (priv->data->flags & GPIO_SYSCON_FEAT_DIR) { + unsigned int offs; + + offs = priv->dir_reg_offset + + priv->data->dir_bit_offset + offset; + + regmap_update_bits(priv->syscon, + (offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE, + BIT(offs % SYSCON_REG_BITS), + BIT(offs % SYSCON_REG_BITS)); + } + + return chip->set(chip, offset, val); +} + +static const struct syscon_gpio_data clps711x_mctrl_gpio = { + /* ARM CLPS711X SYSFLG1 Bits 8-10 */ + .flags = GPIO_SYSCON_FEAT_IN, + .bit_count = 3, + .dat_bit_offset = 0x40 * 8 + 8, +}; + +static int rockchip_gpio_set(struct gpio_chip *chip, unsigned int offset, + int val) +{ + struct syscon_gpio_priv *priv = gpiochip_get_data(chip); + unsigned int offs; + u8 bit; + u32 data; + int ret; + + offs = priv->dreg_offset + priv->data->dat_bit_offset + offset; + bit = offs % SYSCON_REG_BITS; + data = (val ? BIT(bit) : 0) | BIT(bit + 16); + ret = regmap_write(priv->syscon, + (offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE, + data); + if (ret < 0) + dev_err(chip->parent, "gpio write failed ret(%d)\n", ret); + + return ret; +} + +static const struct syscon_gpio_data rockchip_rk3328_gpio_mute = { + /* RK3328 GPIO_MUTE is an output only pin at GRF_SOC_CON10[1] */ + .flags = GPIO_SYSCON_FEAT_OUT, + .bit_count = 1, + .dat_bit_offset = 0x0428 * 8 + 1, + .set = rockchip_gpio_set, +}; + +#define KEYSTONE_LOCK_BIT BIT(0) + +static int keystone_gpio_set(struct gpio_chip *chip, unsigned int offset, + int val) +{ + struct syscon_gpio_priv *priv = gpiochip_get_data(chip); + unsigned int offs; + int ret; + + offs = priv->dreg_offset + priv->data->dat_bit_offset + offset; + + if (!val) + return 0; + + ret = regmap_update_bits( + priv->syscon, + (offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE, + BIT(offs % SYSCON_REG_BITS) | KEYSTONE_LOCK_BIT, + BIT(offs % SYSCON_REG_BITS) | KEYSTONE_LOCK_BIT); + if (ret < 0) + dev_err(chip->parent, "gpio write failed ret(%d)\n", ret); + + return ret; +} + +static const struct syscon_gpio_data keystone_dsp_gpio = { + /* ARM Keystone 2 */ + .flags = GPIO_SYSCON_FEAT_OUT, + .bit_count = 28, + .dat_bit_offset = 4, + .set = keystone_gpio_set, +}; + +static const struct of_device_id syscon_gpio_ids[] = { + { + .compatible = "cirrus,ep7209-mctrl-gpio", + .data = &clps711x_mctrl_gpio, + }, + { + .compatible = "ti,keystone-dsp-gpio", + .data = &keystone_dsp_gpio, + }, + { + .compatible = "rockchip,rk3328-grf-gpio", + .data = &rockchip_rk3328_gpio_mute, + }, + { } +}; +MODULE_DEVICE_TABLE(of, syscon_gpio_ids); + +static int syscon_gpio_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct syscon_gpio_priv *priv; + struct device_node *np = dev->of_node; + int ret; + bool use_parent_regmap = false; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->data = of_device_get_match_data(dev); + + priv->syscon = syscon_regmap_lookup_by_phandle(np, "gpio,syscon-dev"); + if (IS_ERR(priv->syscon) && np->parent) { + priv->syscon = syscon_node_to_regmap(np->parent); + use_parent_regmap = true; + } + if (IS_ERR(priv->syscon)) + return PTR_ERR(priv->syscon); + + if (!use_parent_regmap) { + ret = of_property_read_u32_index(np, "gpio,syscon-dev", 1, + &priv->dreg_offset); + if (ret) + dev_err(dev, "can't read the data register offset!\n"); + + priv->dreg_offset <<= 3; + + ret = of_property_read_u32_index(np, "gpio,syscon-dev", 2, + &priv->dir_reg_offset); + if (ret) + dev_dbg(dev, "can't read the dir register offset!\n"); + + priv->dir_reg_offset <<= 3; + } + + priv->chip.parent = dev; + priv->chip.owner = THIS_MODULE; + priv->chip.label = dev_name(dev); + priv->chip.base = -1; + priv->chip.ngpio = priv->data->bit_count; + priv->chip.get = syscon_gpio_get; + if (priv->data->flags & GPIO_SYSCON_FEAT_IN) + priv->chip.direction_input = syscon_gpio_dir_in; + if (priv->data->flags & GPIO_SYSCON_FEAT_OUT) { + priv->chip.set = priv->data->set ? : syscon_gpio_set; + priv->chip.direction_output = syscon_gpio_dir_out; + } + + return devm_gpiochip_add_data(&pdev->dev, &priv->chip, priv); +} + +static struct platform_driver syscon_gpio_driver = { + .driver = { + .name = "gpio-syscon", + .of_match_table = syscon_gpio_ids, + }, + .probe = syscon_gpio_probe, +}; +module_platform_driver(syscon_gpio_driver); + +MODULE_AUTHOR("Alexander Shiyan "); +MODULE_DESCRIPTION("SYSCON GPIO driver"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1