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/bluetooth/btqcomsmd.c | 234 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 234 insertions(+) create mode 100644 drivers/bluetooth/btqcomsmd.c (limited to 'drivers/bluetooth/btqcomsmd.c') diff --git a/drivers/bluetooth/btqcomsmd.c b/drivers/bluetooth/btqcomsmd.c new file mode 100644 index 000000000..d669ea4eb --- /dev/null +++ b/drivers/bluetooth/btqcomsmd.c @@ -0,0 +1,234 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2016, Linaro Ltd. + * Copyright (c) 2015, Sony Mobile Communications Inc. + */ + +#include +#include +#include +#include + +#include +#include + +#include +#include + +#include "btqca.h" + +struct btqcomsmd { + struct hci_dev *hdev; + + struct rpmsg_endpoint *acl_channel; + struct rpmsg_endpoint *cmd_channel; +}; + +static int btqcomsmd_recv(struct hci_dev *hdev, unsigned int type, + const void *data, size_t count) +{ + struct sk_buff *skb; + + /* Use GFP_ATOMIC as we're in IRQ context */ + skb = bt_skb_alloc(count, GFP_ATOMIC); + if (!skb) { + hdev->stat.err_rx++; + return -ENOMEM; + } + + hci_skb_pkt_type(skb) = type; + skb_put_data(skb, data, count); + + return hci_recv_frame(hdev, skb); +} + +static int btqcomsmd_acl_callback(struct rpmsg_device *rpdev, void *data, + int count, void *priv, u32 addr) +{ + struct btqcomsmd *btq = priv; + + btq->hdev->stat.byte_rx += count; + return btqcomsmd_recv(btq->hdev, HCI_ACLDATA_PKT, data, count); +} + +static int btqcomsmd_cmd_callback(struct rpmsg_device *rpdev, void *data, + int count, void *priv, u32 addr) +{ + struct btqcomsmd *btq = priv; + + btq->hdev->stat.byte_rx += count; + return btqcomsmd_recv(btq->hdev, HCI_EVENT_PKT, data, count); +} + +static int btqcomsmd_send(struct hci_dev *hdev, struct sk_buff *skb) +{ + struct btqcomsmd *btq = hci_get_drvdata(hdev); + int ret; + + switch (hci_skb_pkt_type(skb)) { + case HCI_ACLDATA_PKT: + ret = rpmsg_send(btq->acl_channel, skb->data, skb->len); + if (ret) { + hdev->stat.err_tx++; + break; + } + hdev->stat.acl_tx++; + hdev->stat.byte_tx += skb->len; + break; + case HCI_COMMAND_PKT: + ret = rpmsg_send(btq->cmd_channel, skb->data, skb->len); + if (ret) { + hdev->stat.err_tx++; + break; + } + hdev->stat.cmd_tx++; + hdev->stat.byte_tx += skb->len; + break; + default: + ret = -EILSEQ; + break; + } + + if (!ret) + kfree_skb(skb); + + return ret; +} + +static int btqcomsmd_open(struct hci_dev *hdev) +{ + return 0; +} + +static int btqcomsmd_close(struct hci_dev *hdev) +{ + return 0; +} + +static int btqcomsmd_setup(struct hci_dev *hdev) +{ + struct sk_buff *skb; + + skb = __hci_cmd_sync(hdev, HCI_OP_RESET, 0, NULL, HCI_INIT_TIMEOUT); + if (IS_ERR(skb)) + return PTR_ERR(skb); + kfree_skb(skb); + + /* Devices do not have persistent storage for BD address. Retrieve + * it from the firmware node property. + */ + hci_set_quirk(hdev, HCI_QUIRK_USE_BDADDR_PROPERTY); + + return 0; +} + +static int btqcomsmd_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr) +{ + int ret; + + ret = qca_set_bdaddr_rome(hdev, bdaddr); + if (ret) + return ret; + + /* The firmware stops responding for a while after setting the bdaddr, + * causing timeouts for subsequent commands. Sleep a bit to avoid this. + */ + usleep_range(1000, 10000); + return 0; +} + +static int btqcomsmd_probe(struct platform_device *pdev) +{ + struct btqcomsmd *btq; + struct hci_dev *hdev; + void *wcnss; + int ret; + + btq = devm_kzalloc(&pdev->dev, sizeof(*btq), GFP_KERNEL); + if (!btq) + return -ENOMEM; + + wcnss = dev_get_drvdata(pdev->dev.parent); + + btq->acl_channel = qcom_wcnss_open_channel(wcnss, "APPS_RIVA_BT_ACL", + btqcomsmd_acl_callback, btq); + if (IS_ERR(btq->acl_channel)) + return PTR_ERR(btq->acl_channel); + + btq->cmd_channel = qcom_wcnss_open_channel(wcnss, "APPS_RIVA_BT_CMD", + btqcomsmd_cmd_callback, btq); + if (IS_ERR(btq->cmd_channel)) { + ret = PTR_ERR(btq->cmd_channel); + goto destroy_acl_channel; + } + + hdev = hci_alloc_dev(); + if (!hdev) { + ret = -ENOMEM; + goto destroy_cmd_channel; + } + + hci_set_drvdata(hdev, btq); + btq->hdev = hdev; + SET_HCIDEV_DEV(hdev, &pdev->dev); + + hdev->bus = HCI_SMD; + hdev->open = btqcomsmd_open; + hdev->close = btqcomsmd_close; + hdev->send = btqcomsmd_send; + hdev->setup = btqcomsmd_setup; + hdev->set_bdaddr = btqcomsmd_set_bdaddr; + + ret = hci_register_dev(hdev); + if (ret < 0) + goto hci_free_dev; + + platform_set_drvdata(pdev, btq); + + return 0; + +hci_free_dev: + rpmsg_destroy_ept(btq->cmd_channel); + rpmsg_destroy_ept(btq->acl_channel); + hci_free_dev(hdev); + return ret; +destroy_cmd_channel: + rpmsg_destroy_ept(btq->cmd_channel); +destroy_acl_channel: + rpmsg_destroy_ept(btq->acl_channel); + + return ret; +} + +static void btqcomsmd_remove(struct platform_device *pdev) +{ + struct btqcomsmd *btq = platform_get_drvdata(pdev); + + hci_unregister_dev(btq->hdev); + + rpmsg_destroy_ept(btq->cmd_channel); + rpmsg_destroy_ept(btq->acl_channel); + + hci_free_dev(btq->hdev); +} + +static const struct of_device_id btqcomsmd_of_match[] = { + { .compatible = "qcom,wcnss-bt", }, + { }, +}; +MODULE_DEVICE_TABLE(of, btqcomsmd_of_match); + +static struct platform_driver btqcomsmd_driver = { + .probe = btqcomsmd_probe, + .remove = btqcomsmd_remove, + .driver = { + .name = "btqcomsmd", + .of_match_table = btqcomsmd_of_match, + }, +}; + +module_platform_driver(btqcomsmd_driver); + +MODULE_AUTHOR("Bjorn Andersson "); +MODULE_DESCRIPTION("Qualcomm SMD HCI driver"); +MODULE_LICENSE("GPL v2"); -- cgit v1.3.1