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-ezkey.c | 79 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 79 insertions(+) create mode 100644 drivers/hid/hid-ezkey.c (limited to 'drivers/hid/hid-ezkey.c') diff --git a/drivers/hid/hid-ezkey.c b/drivers/hid/hid-ezkey.c new file mode 100644 index 000000000..0e28bc0b8 --- /dev/null +++ b/drivers/hid/hid-ezkey.c @@ -0,0 +1,79 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * HID driver for some ezkey "special" devices + * + * Copyright (c) 1999 Andreas Gal + * Copyright (c) 2000-2005 Vojtech Pavlik + * Copyright (c) 2005 Michael Haboustak for Concept2, Inc + * Copyright (c) 2006-2007 Jiri Kosina + * Copyright (c) 2008 Jiri Slaby + */ + +/* + */ + +#include +#include +#include +#include + +#include "hid-ids.h" + +#define ez_map_rel(c) hid_map_usage(hi, usage, bit, max, EV_REL, (c)) +#define ez_map_key(c) hid_map_usage(hi, usage, bit, max, EV_KEY, (c)) + +static int ez_input_mapping(struct hid_device *hdev, struct hid_input *hi, + struct hid_field *field, struct hid_usage *usage, + unsigned long **bit, int *max) +{ + if ((usage->hid & HID_USAGE_PAGE) != HID_UP_CONSUMER) + return 0; + + switch (usage->hid & HID_USAGE) { + case 0x230: ez_map_key(BTN_MOUSE); break; + case 0x231: ez_map_rel(REL_WHEEL); break; + /* + * this keyboard has a scrollwheel implemented in + * totally broken way. We map this usage temporarily + * to HWHEEL and handle it in the event quirk handler + */ + case 0x232: ez_map_rel(REL_HWHEEL); break; + default: + return 0; + } + return 1; +} + +static int ez_event(struct hid_device *hdev, struct hid_field *field, + struct hid_usage *usage, __s32 value) +{ + if (!(hdev->claimed & HID_CLAIMED_INPUT) || !field->hidinput || + !usage->type) + return 0; + + /* handle the temporary quirky mapping to HWHEEL */ + if (usage->type == EV_REL && usage->code == REL_HWHEEL) { + struct input_dev *input = field->hidinput->input; + input_event(input, usage->type, REL_WHEEL, -value); + return 1; + } + + return 0; +} + +static const struct hid_device_id ez_devices[] = { + { HID_USB_DEVICE(USB_VENDOR_ID_EZKEY, USB_DEVICE_ID_BTC_8193) }, + { } +}; +MODULE_DEVICE_TABLE(hid, ez_devices); + +static struct hid_driver ez_driver = { + .name = "ezkey", + .id_table = ez_devices, + .input_mapping = ez_input_mapping, + .event = ez_event, +}; +module_hid_driver(ez_driver); + +MODULE_DESCRIPTION("HID driver for some ezkey \"special\" devices"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1