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/hid/hid-evision.c | 75 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 75 insertions(+) create mode 100644 drivers/hid/hid-evision.c (limited to 'drivers/hid/hid-evision.c') diff --git a/drivers/hid/hid-evision.c b/drivers/hid/hid-evision.c new file mode 100644 index 000000000..3e7f43ab8 --- /dev/null +++ b/drivers/hid/hid-evision.c @@ -0,0 +1,75 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * HID driver for EVision devices + * For now, only ignore bogus consumer reports + * sent after the keyboard has been configured + * + * Copyright (c) 2022 Philippe Valembois + */ + +#include +#include +#include +#include + +#include "hid-ids.h" + +static int evision_input_mapping(struct hid_device *hdev, struct hid_input *hi, + struct hid_field *field, struct hid_usage *usage, + unsigned long **bit, int *max) +{ + /* mapping only applies to USB_DEVICE_ID_EVISION_ICL01 */ + if (hdev->product != USB_DEVICE_ID_EVISION_ICL01) + return 0; + + if ((usage->hid & HID_USAGE_PAGE) != HID_UP_CONSUMER) + return 0; + + /* Ignore key down event */ + if ((usage->hid & HID_USAGE) >> 8 == 0x05) + return -1; + /* Ignore key up event */ + if ((usage->hid & HID_USAGE) >> 8 == 0x06) + return -1; + + switch (usage->hid & HID_USAGE) { + /* Ignore configuration saved event */ + case 0x0401: return -1; + /* Ignore reset event */ + case 0x0402: return -1; + } + return 0; +} + +#define REP_DSC_SIZE 236 +#define USAGE_MAX_INDEX 59 + +static const __u8 *evision_report_fixup(struct hid_device *hdev, __u8 *rdesc, + unsigned int *rsize) +{ + if (hdev->product == USB_DEVICE_ID_EV_TELINK_RECEIVER && + *rsize == REP_DSC_SIZE && rdesc[USAGE_MAX_INDEX] == 0x29 && + rdesc[USAGE_MAX_INDEX + 1] == 3) { + hid_info(hdev, "fixing EVision:TeLink Receiver report descriptor\n"); + rdesc[USAGE_MAX_INDEX + 1] = 5; // change usage max from 3 to 5 + } + return rdesc; +} + +static const struct hid_device_id evision_devices[] = { + { HID_USB_DEVICE(USB_VENDOR_ID_EVISION, USB_DEVICE_ID_EVISION_ICL01) }, + { HID_USB_DEVICE(USB_VENDOR_ID_EVISION, USB_DEVICE_ID_EV_TELINK_RECEIVER) }, + { } +}; +MODULE_DEVICE_TABLE(hid, evision_devices); + +static struct hid_driver evision_driver = { + .name = "evision", + .id_table = evision_devices, + .input_mapping = evision_input_mapping, + .report_fixup = evision_report_fixup, +}; +module_hid_driver(evision_driver); + +MODULE_DESCRIPTION("HID driver for EVision devices"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1