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/usb/chipidea/ulpi.c | 108 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 108 insertions(+) create mode 100644 drivers/usb/chipidea/ulpi.c (limited to 'drivers/usb/chipidea/ulpi.c') diff --git a/drivers/usb/chipidea/ulpi.c b/drivers/usb/chipidea/ulpi.c new file mode 100644 index 000000000..dfec07e8a --- /dev/null +++ b/drivers/usb/chipidea/ulpi.c @@ -0,0 +1,108 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2016 Linaro Ltd. + */ + +#include +#include +#include + +#include "ci.h" + +#define ULPI_WAKEUP BIT(31) +#define ULPI_RUN BIT(30) +#define ULPI_WRITE BIT(29) +#define ULPI_SYNC_STATE BIT(27) +#define ULPI_ADDR(n) ((n) << 16) +#define ULPI_DATA(n) (n) + +static int ci_ulpi_wait(struct ci_hdrc *ci, u32 mask) +{ + unsigned long usec = 10000; + + while (usec--) { + if (!hw_read(ci, OP_ULPI_VIEWPORT, mask)) + return 0; + + udelay(1); + } + + return -ETIMEDOUT; +} + +static int ci_ulpi_read(struct device *dev, u8 addr) +{ + struct ci_hdrc *ci = dev_get_drvdata(dev); + int ret; + + hw_write(ci, OP_ULPI_VIEWPORT, 0xffffffff, ULPI_WRITE | ULPI_WAKEUP); + ret = ci_ulpi_wait(ci, ULPI_WAKEUP); + if (ret) + return ret; + + hw_write(ci, OP_ULPI_VIEWPORT, 0xffffffff, ULPI_RUN | ULPI_ADDR(addr)); + ret = ci_ulpi_wait(ci, ULPI_RUN); + if (ret) + return ret; + + return hw_read(ci, OP_ULPI_VIEWPORT, GENMASK(15, 8)) >> 8; +} + +static int ci_ulpi_write(struct device *dev, u8 addr, u8 val) +{ + struct ci_hdrc *ci = dev_get_drvdata(dev); + int ret; + + hw_write(ci, OP_ULPI_VIEWPORT, 0xffffffff, ULPI_WRITE | ULPI_WAKEUP); + ret = ci_ulpi_wait(ci, ULPI_WAKEUP); + if (ret) + return ret; + + hw_write(ci, OP_ULPI_VIEWPORT, 0xffffffff, + ULPI_RUN | ULPI_WRITE | ULPI_ADDR(addr) | val); + return ci_ulpi_wait(ci, ULPI_RUN); +} + +int ci_ulpi_init(struct ci_hdrc *ci) +{ + if (ci->platdata->phy_mode != USBPHY_INTERFACE_MODE_ULPI) + return 0; + + /* + * Set PORTSC correctly so we can read/write ULPI registers for + * identification purposes + */ + hw_phymode_configure(ci); + + ci->ulpi_ops.read = ci_ulpi_read; + ci->ulpi_ops.write = ci_ulpi_write; + ci->ulpi = ulpi_register_interface(ci->dev, &ci->ulpi_ops); + if (IS_ERR(ci->ulpi)) + dev_err(ci->dev, "failed to register ULPI interface"); + + return PTR_ERR_OR_ZERO(ci->ulpi); +} + +void ci_ulpi_exit(struct ci_hdrc *ci) +{ + if (ci->ulpi) { + ulpi_unregister_interface(ci->ulpi); + ci->ulpi = NULL; + } +} + +int ci_ulpi_resume(struct ci_hdrc *ci) +{ + int cnt = 100000; + + if (ci->platdata->phy_mode != USBPHY_INTERFACE_MODE_ULPI) + return 0; + + while (cnt-- > 0) { + if (hw_read(ci, OP_ULPI_VIEWPORT, ULPI_SYNC_STATE)) + return 0; + udelay(1); + } + + return -ETIMEDOUT; +} -- cgit v1.3.1