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/input/misc/e3x0-button.c | 135 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 135 insertions(+) create mode 100644 drivers/input/misc/e3x0-button.c (limited to 'drivers/input/misc/e3x0-button.c') diff --git a/drivers/input/misc/e3x0-button.c b/drivers/input/misc/e3x0-button.c new file mode 100644 index 000000000..5bd527117 --- /dev/null +++ b/drivers/input/misc/e3x0-button.c @@ -0,0 +1,135 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2014, National Instruments Corp. All rights reserved. + * + * Driver for NI Ettus Research USRP E3x0 Button Driver + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +static irqreturn_t e3x0_button_release_handler(int irq, void *data) +{ + struct input_dev *idev = data; + + input_report_key(idev, KEY_POWER, 0); + input_sync(idev); + + return IRQ_HANDLED; +} + +static irqreturn_t e3x0_button_press_handler(int irq, void *data) +{ + struct input_dev *idev = data; + + input_report_key(idev, KEY_POWER, 1); + pm_wakeup_event(idev->dev.parent, 0); + input_sync(idev); + + return IRQ_HANDLED; +} + +static int e3x0_button_suspend(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + + if (device_may_wakeup(dev)) + enable_irq_wake(platform_get_irq_byname(pdev, "press")); + + return 0; +} + +static int e3x0_button_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + + if (device_may_wakeup(dev)) + disable_irq_wake(platform_get_irq_byname(pdev, "press")); + + return 0; +} + +static DEFINE_SIMPLE_DEV_PM_OPS(e3x0_button_pm_ops, + e3x0_button_suspend, e3x0_button_resume); + +static int e3x0_button_probe(struct platform_device *pdev) +{ + struct input_dev *input; + int irq_press, irq_release; + int error; + + irq_press = platform_get_irq_byname(pdev, "press"); + if (irq_press < 0) + return irq_press; + + irq_release = platform_get_irq_byname(pdev, "release"); + if (irq_release < 0) + return irq_release; + + input = devm_input_allocate_device(&pdev->dev); + if (!input) + return -ENOMEM; + + input->name = "NI Ettus Research USRP E3x0 Button Driver"; + input->phys = "e3x0_button/input0"; + input->dev.parent = &pdev->dev; + + input_set_capability(input, EV_KEY, KEY_POWER); + + error = devm_request_irq(&pdev->dev, irq_press, + e3x0_button_press_handler, 0, + "e3x0-button", input); + if (error) { + dev_err(&pdev->dev, "Failed to request 'press' IRQ#%d: %d\n", + irq_press, error); + return error; + } + + error = devm_request_irq(&pdev->dev, irq_release, + e3x0_button_release_handler, 0, + "e3x0-button", input); + if (error) { + dev_err(&pdev->dev, "Failed to request 'release' IRQ#%d: %d\n", + irq_release, error); + return error; + } + + error = input_register_device(input); + if (error) { + dev_err(&pdev->dev, "Can't register input device: %d\n", error); + return error; + } + + device_init_wakeup(&pdev->dev, 1); + return 0; +} + +#ifdef CONFIG_OF +static const struct of_device_id e3x0_button_match[] = { + { .compatible = "ettus,e3x0-button", }, + { } +}; +MODULE_DEVICE_TABLE(of, e3x0_button_match); +#endif + +static struct platform_driver e3x0_button_driver = { + .driver = { + .name = "e3x0-button", + .of_match_table = of_match_ptr(e3x0_button_match), + .pm = pm_sleep_ptr(&e3x0_button_pm_ops), + }, + .probe = e3x0_button_probe, +}; + +module_platform_driver(e3x0_button_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Moritz Fischer "); +MODULE_DESCRIPTION("NI Ettus Research USRP E3x0 Button driver"); +MODULE_ALIAS("platform:e3x0-button"); -- cgit v1.3.1