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/net/phy/lxt.c | 358 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 358 insertions(+) create mode 100644 drivers/net/phy/lxt.c (limited to 'drivers/net/phy/lxt.c') diff --git a/drivers/net/phy/lxt.c b/drivers/net/phy/lxt.c new file mode 100644 index 000000000..5251a61c8 --- /dev/null +++ b/drivers/net/phy/lxt.c @@ -0,0 +1,358 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * drivers/net/phy/lxt.c + * + * Driver for Intel LXT PHYs + * + * Author: Andy Fleming + * + * Copyright (c) 2004 Freescale Semiconductor, Inc. + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +/* The Level one LXT970 is used by many boards */ + +#define MII_LXT970_IER 17 /* Interrupt Enable Register */ + +#define MII_LXT970_IER_IEN 0x0002 + +#define MII_LXT970_ISR 18 /* Interrupt Status Register */ + +#define MII_LXT970_IRS_MINT BIT(15) + +#define MII_LXT970_CONFIG 19 /* Configuration Register */ + +/* ------------------------------------------------------------------------- */ +/* The Level one LXT971 is used on some of my custom boards */ + +/* register definitions for the 971 */ +#define MII_LXT971_IER 18 /* Interrupt Enable Register */ +#define MII_LXT971_IER_IEN 0x00f2 + +#define MII_LXT971_ISR 19 /* Interrupt Status Register */ +#define MII_LXT971_ISR_MASK 0x00f0 + +/* register definitions for the 973 */ +#define MII_LXT973_PCR 16 /* Port Configuration Register */ +#define PCR_FIBER_SELECT 1 + +MODULE_DESCRIPTION("Intel LXT PHY driver"); +MODULE_AUTHOR("Andy Fleming"); +MODULE_LICENSE("GPL"); + +static int lxt970_ack_interrupt(struct phy_device *phydev) +{ + int err; + + err = phy_read(phydev, MII_BMSR); + + if (err < 0) + return err; + + err = phy_read(phydev, MII_LXT970_ISR); + + if (err < 0) + return err; + + return 0; +} + +static int lxt970_config_intr(struct phy_device *phydev) +{ + int err; + + if (phydev->interrupts == PHY_INTERRUPT_ENABLED) { + err = lxt970_ack_interrupt(phydev); + if (err) + return err; + + err = phy_write(phydev, MII_LXT970_IER, MII_LXT970_IER_IEN); + } else { + err = phy_write(phydev, MII_LXT970_IER, 0); + if (err) + return err; + + err = lxt970_ack_interrupt(phydev); + } + + return err; +} + +static irqreturn_t lxt970_handle_interrupt(struct phy_device *phydev) +{ + int irq_status; + + /* The interrupt status register is cleared by reading BMSR + * followed by MII_LXT970_ISR + */ + irq_status = phy_read(phydev, MII_BMSR); + if (irq_status < 0) { + phy_error(phydev); + return IRQ_NONE; + } + + irq_status = phy_read(phydev, MII_LXT970_ISR); + if (irq_status < 0) { + phy_error(phydev); + return IRQ_NONE; + } + + if (!(irq_status & MII_LXT970_IRS_MINT)) + return IRQ_NONE; + + phy_trigger_machine(phydev); + + return IRQ_HANDLED; +} + +static int lxt970_config_init(struct phy_device *phydev) +{ + return phy_write(phydev, MII_LXT970_CONFIG, 0); +} + + +static int lxt971_ack_interrupt(struct phy_device *phydev) +{ + int err = phy_read(phydev, MII_LXT971_ISR); + + if (err < 0) + return err; + + return 0; +} + +static int lxt971_config_intr(struct phy_device *phydev) +{ + int err; + + if (phydev->interrupts == PHY_INTERRUPT_ENABLED) { + err = lxt971_ack_interrupt(phydev); + if (err) + return err; + + err = phy_write(phydev, MII_LXT971_IER, MII_LXT971_IER_IEN); + } else { + err = phy_write(phydev, MII_LXT971_IER, 0); + if (err) + return err; + + err = lxt971_ack_interrupt(phydev); + } + + return err; +} + +static irqreturn_t lxt971_handle_interrupt(struct phy_device *phydev) +{ + int irq_status; + + irq_status = phy_read(phydev, MII_LXT971_ISR); + if (irq_status < 0) { + phy_error(phydev); + return IRQ_NONE; + } + + if (!(irq_status & MII_LXT971_ISR_MASK)) + return IRQ_NONE; + + phy_trigger_machine(phydev); + + return IRQ_HANDLED; +} + +/* + * A2 version of LXT973 chip has an ERRATA: it randomly return the contents + * of the previous even register when you read a odd register regularly + */ + +static int lxt973a2_update_link(struct phy_device *phydev) +{ + int status; + int control; + int retry = 8; /* we try 8 times */ + + /* Do a fake read */ + status = phy_read(phydev, MII_BMSR); + + if (status < 0) + return status; + + control = phy_read(phydev, MII_BMCR); + if (control < 0) + return control; + + do { + /* Read link and autonegotiation status */ + status = phy_read(phydev, MII_BMSR); + } while (status >= 0 && retry-- && status == control); + + if (status < 0) + return status; + + if ((status & BMSR_LSTATUS) == 0) + phydev->link = 0; + else + phydev->link = 1; + + return 0; +} + +static int lxt973a2_read_status(struct phy_device *phydev) +{ + int adv; + int err; + int lpa; + + /* Update the link, but return if there was an error */ + err = lxt973a2_update_link(phydev); + if (err) + return err; + + if (AUTONEG_ENABLE == phydev->autoneg) { + int retry = 1; + + adv = phy_read(phydev, MII_ADVERTISE); + + if (adv < 0) + return adv; + + do { + lpa = phy_read(phydev, MII_LPA); + + if (lpa < 0) + return lpa; + + /* If both registers are equal, it is suspect but not + * impossible, hence a new try + */ + } while (lpa == adv && retry--); + + mii_lpa_to_linkmode_lpa_t(phydev->lp_advertising, lpa); + + lpa &= adv; + + phydev->speed = SPEED_10; + phydev->duplex = DUPLEX_HALF; + phydev->pause = phydev->asym_pause = 0; + + if (lpa & (LPA_100FULL | LPA_100HALF)) { + phydev->speed = SPEED_100; + + if (lpa & LPA_100FULL) + phydev->duplex = DUPLEX_FULL; + } else { + if (lpa & LPA_10FULL) + phydev->duplex = DUPLEX_FULL; + } + + phy_resolve_aneg_pause(phydev); + } else { + err = genphy_read_status_fixed(phydev); + if (err < 0) + return err; + + phydev->pause = phydev->asym_pause = 0; + linkmode_zero(phydev->lp_advertising); + } + + return 0; +} + +static int lxt973_probe(struct phy_device *phydev) +{ + int val = phy_read(phydev, MII_LXT973_PCR); + + if (val & PCR_FIBER_SELECT) { + /* + * If fiber is selected, then the only correct setting + * is 100Mbps, full duplex, and auto negotiation off. + */ + val = phy_read(phydev, MII_BMCR); + val |= (BMCR_SPEED100 | BMCR_FULLDPLX); + val &= ~BMCR_ANENABLE; + phy_write(phydev, MII_BMCR, val); + /* Remember that the port is in fiber mode. */ + phydev->priv = lxt973_probe; + phydev->port = PORT_FIBRE; + } else { + phydev->priv = NULL; + } + return 0; +} + +static int lxt973_config_aneg(struct phy_device *phydev) +{ + /* Do nothing if port is in fiber mode. */ + return phydev->priv ? 0 : genphy_config_aneg(phydev); +} + +static struct phy_driver lxt97x_driver[] = { +{ + .phy_id = 0x78100000, + .name = "LXT970", + .phy_id_mask = 0xfffffff0, + /* PHY_BASIC_FEATURES */ + .config_init = lxt970_config_init, + .config_intr = lxt970_config_intr, + .handle_interrupt = lxt970_handle_interrupt, +}, { + .phy_id = 0x001378e0, + .name = "LXT971", + .phy_id_mask = 0xfffffff0, + /* PHY_BASIC_FEATURES */ + .config_intr = lxt971_config_intr, + .handle_interrupt = lxt971_handle_interrupt, + .suspend = genphy_suspend, + .resume = genphy_resume, +}, { + .phy_id = 0x00137a10, + .name = "LXT973-A2", + .phy_id_mask = 0xffffffff, + /* PHY_BASIC_FEATURES */ + .flags = 0, + .probe = lxt973_probe, + .config_aneg = lxt973_config_aneg, + .read_status = lxt973a2_read_status, + .suspend = genphy_suspend, + .resume = genphy_resume, +}, { + .phy_id = 0x00137a10, + .name = "LXT973", + .phy_id_mask = 0xfffffff0, + /* PHY_BASIC_FEATURES */ + .flags = 0, + .probe = lxt973_probe, + .config_aneg = lxt973_config_aneg, + .suspend = genphy_suspend, + .resume = genphy_resume, +} }; + +module_phy_driver(lxt97x_driver); + +static const struct mdio_device_id __maybe_unused lxt_tbl[] = { + { 0x78100000, 0xfffffff0 }, + { 0x001378e0, 0xfffffff0 }, + { 0x00137a10, 0xfffffff0 }, + { } +}; + +MODULE_DEVICE_TABLE(mdio, lxt_tbl); -- cgit v1.3.1