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/firewire/uapi-test.c | 90 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 90 insertions(+) create mode 100644 drivers/firewire/uapi-test.c (limited to 'drivers/firewire/uapi-test.c') diff --git a/drivers/firewire/uapi-test.c b/drivers/firewire/uapi-test.c new file mode 100644 index 000000000..bc3f10a2e --- /dev/null +++ b/drivers/firewire/uapi-test.c @@ -0,0 +1,90 @@ +// SPDX-License-Identifier: GPL-2.0-only +// +// uapi_test.c - An application of Kunit to check layout of structures exposed to user space for +// FireWire subsystem. +// +// Copyright (c) 2023 Takashi Sakamoto + +#include +#include + +// Known issue added at v2.6.27 kernel. +static void structure_layout_event_response(struct kunit *test) +{ +#if defined(CONFIG_X86_32) + // 4 bytes alignment for aggregate type including 8 bytes storage types. + KUNIT_EXPECT_EQ(test, 20, sizeof(struct fw_cdev_event_response)); +#else + // 8 bytes alignment for aggregate type including 8 bytes storage types. + KUNIT_EXPECT_EQ(test, 24, sizeof(struct fw_cdev_event_response)); +#endif + + KUNIT_EXPECT_EQ(test, 0, offsetof(struct fw_cdev_event_response, closure)); + KUNIT_EXPECT_EQ(test, 8, offsetof(struct fw_cdev_event_response, type)); + KUNIT_EXPECT_EQ(test, 12, offsetof(struct fw_cdev_event_response, rcode)); + KUNIT_EXPECT_EQ(test, 16, offsetof(struct fw_cdev_event_response, length)); + KUNIT_EXPECT_EQ(test, 20, offsetof(struct fw_cdev_event_response, data)); +} + +// Added at v6.5. +static void structure_layout_event_request3(struct kunit *test) +{ + KUNIT_EXPECT_EQ(test, 56, sizeof(struct fw_cdev_event_request3)); + + KUNIT_EXPECT_EQ(test, 0, offsetof(struct fw_cdev_event_request3, closure)); + KUNIT_EXPECT_EQ(test, 8, offsetof(struct fw_cdev_event_request3, type)); + KUNIT_EXPECT_EQ(test, 12, offsetof(struct fw_cdev_event_request3, tcode)); + KUNIT_EXPECT_EQ(test, 16, offsetof(struct fw_cdev_event_request3, offset)); + KUNIT_EXPECT_EQ(test, 24, offsetof(struct fw_cdev_event_request3, source_node_id)); + KUNIT_EXPECT_EQ(test, 28, offsetof(struct fw_cdev_event_request3, destination_node_id)); + KUNIT_EXPECT_EQ(test, 32, offsetof(struct fw_cdev_event_request3, card)); + KUNIT_EXPECT_EQ(test, 36, offsetof(struct fw_cdev_event_request3, generation)); + KUNIT_EXPECT_EQ(test, 40, offsetof(struct fw_cdev_event_request3, handle)); + KUNIT_EXPECT_EQ(test, 44, offsetof(struct fw_cdev_event_request3, length)); + KUNIT_EXPECT_EQ(test, 48, offsetof(struct fw_cdev_event_request3, tstamp)); + KUNIT_EXPECT_EQ(test, 56, offsetof(struct fw_cdev_event_request3, data)); +} + +// Added at v6.5. +static void structure_layout_event_response2(struct kunit *test) +{ + KUNIT_EXPECT_EQ(test, 32, sizeof(struct fw_cdev_event_response2)); + + KUNIT_EXPECT_EQ(test, 0, offsetof(struct fw_cdev_event_response2, closure)); + KUNIT_EXPECT_EQ(test, 8, offsetof(struct fw_cdev_event_response2, type)); + KUNIT_EXPECT_EQ(test, 12, offsetof(struct fw_cdev_event_response2, rcode)); + KUNIT_EXPECT_EQ(test, 16, offsetof(struct fw_cdev_event_response2, length)); + KUNIT_EXPECT_EQ(test, 20, offsetof(struct fw_cdev_event_response2, request_tstamp)); + KUNIT_EXPECT_EQ(test, 24, offsetof(struct fw_cdev_event_response2, response_tstamp)); + KUNIT_EXPECT_EQ(test, 32, offsetof(struct fw_cdev_event_response2, data)); +} + +// Added at v6.5. +static void structure_layout_event_phy_packet2(struct kunit *test) +{ + KUNIT_EXPECT_EQ(test, 24, sizeof(struct fw_cdev_event_phy_packet2)); + + KUNIT_EXPECT_EQ(test, 0, offsetof(struct fw_cdev_event_phy_packet2, closure)); + KUNIT_EXPECT_EQ(test, 8, offsetof(struct fw_cdev_event_phy_packet2, type)); + KUNIT_EXPECT_EQ(test, 12, offsetof(struct fw_cdev_event_phy_packet2, rcode)); + KUNIT_EXPECT_EQ(test, 16, offsetof(struct fw_cdev_event_phy_packet2, length)); + KUNIT_EXPECT_EQ(test, 20, offsetof(struct fw_cdev_event_phy_packet2, tstamp)); + KUNIT_EXPECT_EQ(test, 24, offsetof(struct fw_cdev_event_phy_packet2, data)); +} + +static struct kunit_case structure_layout_test_cases[] = { + KUNIT_CASE(structure_layout_event_response), + KUNIT_CASE(structure_layout_event_request3), + KUNIT_CASE(structure_layout_event_response2), + KUNIT_CASE(structure_layout_event_phy_packet2), + {} +}; + +static struct kunit_suite structure_layout_test_suite = { + .name = "firewire-uapi-structure-layout", + .test_cases = structure_layout_test_cases, +}; +kunit_test_suite(structure_layout_test_suite); + +MODULE_DESCRIPTION("FireWire UAPI unit test suite"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1