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/video/fbdev/i810/Makefile | 18 + drivers/video/fbdev/i810/i810-i2c.c | 175 +++ drivers/video/fbdev/i810/i810.h | 298 +++++ drivers/video/fbdev/i810/i810_accel.c | 456 +++++++ drivers/video/fbdev/i810/i810_dvt.c | 313 +++++ drivers/video/fbdev/i810/i810_gtf.c | 276 ++++ drivers/video/fbdev/i810/i810_main.c | 2234 +++++++++++++++++++++++++++++++++ drivers/video/fbdev/i810/i810_main.h | 69 + drivers/video/fbdev/i810/i810_regs.h | 275 ++++ 9 files changed, 4114 insertions(+) create mode 100644 drivers/video/fbdev/i810/Makefile create mode 100644 drivers/video/fbdev/i810/i810-i2c.c create mode 100644 drivers/video/fbdev/i810/i810.h create mode 100644 drivers/video/fbdev/i810/i810_accel.c create mode 100644 drivers/video/fbdev/i810/i810_dvt.c create mode 100644 drivers/video/fbdev/i810/i810_gtf.c create mode 100644 drivers/video/fbdev/i810/i810_main.c create mode 100644 drivers/video/fbdev/i810/i810_main.h create mode 100644 drivers/video/fbdev/i810/i810_regs.h (limited to 'drivers/video/fbdev/i810') diff --git a/drivers/video/fbdev/i810/Makefile b/drivers/video/fbdev/i810/Makefile new file mode 100644 index 000000000..3e466510f --- /dev/null +++ b/drivers/video/fbdev/i810/Makefile @@ -0,0 +1,18 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for the Intel 810/815 framebuffer driver +# + +obj-$(CONFIG_FB_I810) += i810fb.o + +i810fb-objs := i810_main.o i810_accel.o + +ifdef CONFIG_FB_I810_GTF +i810fb-objs += i810_gtf.o +else +i810fb-objs += i810_dvt.o +endif + +ifdef CONFIG_FB_I810_I2C +i810fb-objs += i810-i2c.o +endif diff --git a/drivers/video/fbdev/i810/i810-i2c.c b/drivers/video/fbdev/i810/i810-i2c.c new file mode 100644 index 000000000..7db17d0d8 --- /dev/null +++ b/drivers/video/fbdev/i810/i810-i2c.c @@ -0,0 +1,175 @@ + /*-*- linux-c -*- + * linux/drivers/video/i810-i2c.c -- Intel 810/815 I2C support + * + * Copyright (C) 2004 Antonino Daplas + * All Rights Reserved + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of this archive for + * more details. + */ +#include +#include +#include +#include +#include +#include +#include "i810.h" +#include "i810_regs.h" +#include "i810_main.h" +#include "../edid.h" + +/* bit locations in the registers */ +#define SCL_DIR_MASK 0x0001 +#define SCL_DIR 0x0002 +#define SCL_VAL_MASK 0x0004 +#define SCL_VAL_OUT 0x0008 +#define SCL_VAL_IN 0x0010 +#define SDA_DIR_MASK 0x0100 +#define SDA_DIR 0x0200 +#define SDA_VAL_MASK 0x0400 +#define SDA_VAL_OUT 0x0800 +#define SDA_VAL_IN 0x1000 + +#define DEBUG /* define this for verbose EDID parsing output */ + +#ifdef DEBUG +#define DPRINTK(fmt, args...) printk(fmt,## args) +#else +#define DPRINTK(fmt, args...) +#endif + +static void i810i2c_setscl(void *data, int state) +{ + struct i810fb_i2c_chan *chan = data; + struct i810fb_par *par = chan->par; + u8 __iomem *mmio = par->mmio_start_virtual; + + if (state) + i810_writel(mmio, chan->ddc_base, SCL_DIR_MASK | SCL_VAL_MASK); + else + i810_writel(mmio, chan->ddc_base, SCL_DIR | SCL_DIR_MASK | SCL_VAL_MASK); + i810_readl(mmio, chan->ddc_base); /* flush posted write */ +} + +static void i810i2c_setsda(void *data, int state) +{ + struct i810fb_i2c_chan *chan = data; + struct i810fb_par *par = chan->par; + u8 __iomem *mmio = par->mmio_start_virtual; + + if (state) + i810_writel(mmio, chan->ddc_base, SDA_DIR_MASK | SDA_VAL_MASK); + else + i810_writel(mmio, chan->ddc_base, SDA_DIR | SDA_DIR_MASK | SDA_VAL_MASK); + i810_readl(mmio, chan->ddc_base); /* flush posted write */ +} + +static int i810i2c_getscl(void *data) +{ + struct i810fb_i2c_chan *chan = data; + struct i810fb_par *par = chan->par; + u8 __iomem *mmio = par->mmio_start_virtual; + + i810_writel(mmio, chan->ddc_base, SCL_DIR_MASK); + i810_writel(mmio, chan->ddc_base, 0); + return ((i810_readl(mmio, chan->ddc_base) & SCL_VAL_IN) != 0); +} + +static int i810i2c_getsda(void *data) +{ + struct i810fb_i2c_chan *chan = data; + struct i810fb_par *par = chan->par; + u8 __iomem *mmio = par->mmio_start_virtual; + + i810_writel(mmio, chan->ddc_base, SDA_DIR_MASK); + i810_writel(mmio, chan->ddc_base, 0); + return ((i810_readl(mmio, chan->ddc_base) & SDA_VAL_IN) != 0); +} + +static int i810_setup_i2c_bus(struct i810fb_i2c_chan *chan, const char *name) +{ + int rc; + + strcpy(chan->adapter.name, name); + chan->adapter.owner = THIS_MODULE; + chan->adapter.algo_data = &chan->algo; + chan->adapter.dev.parent = &chan->par->dev->dev; + chan->algo.setsda = i810i2c_setsda; + chan->algo.setscl = i810i2c_setscl; + chan->algo.getsda = i810i2c_getsda; + chan->algo.getscl = i810i2c_getscl; + chan->algo.udelay = 10; + chan->algo.timeout = (HZ/2); + chan->algo.data = chan; + + i2c_set_adapdata(&chan->adapter, chan); + + /* Raise SCL and SDA */ + chan->algo.setsda(chan, 1); + chan->algo.setscl(chan, 1); + udelay(20); + + rc = i2c_bit_add_bus(&chan->adapter); + + if (rc == 0) + dev_dbg(&chan->par->dev->dev, "I2C bus %s registered.\n",name); + else { + dev_warn(&chan->par->dev->dev, "Failed to register I2C bus " + "%s.\n", name); + chan->par = NULL; + } + + return rc; +} + +void i810_create_i2c_busses(struct i810fb_par *par) +{ + par->chan[0].par = par; + par->chan[1].par = par; + par->chan[2].par = par; + + par->chan[0].ddc_base = GPIOA; + i810_setup_i2c_bus(&par->chan[0], "I810-DDC"); + par->chan[1].ddc_base = GPIOB; + i810_setup_i2c_bus(&par->chan[1], "I810-I2C"); + par->chan[2].ddc_base = GPIOC; + i810_setup_i2c_bus(&par->chan[2], "I810-GPIOC"); +} + +void i810_delete_i2c_busses(struct i810fb_par *par) +{ + if (par->chan[0].par) + i2c_del_adapter(&par->chan[0].adapter); + par->chan[0].par = NULL; + + if (par->chan[1].par) + i2c_del_adapter(&par->chan[1].adapter); + par->chan[1].par = NULL; + + if (par->chan[2].par) + i2c_del_adapter(&par->chan[2].adapter); + par->chan[2].par = NULL; +} + +int i810_probe_i2c_connector(struct fb_info *info, u8 **out_edid, int conn) +{ + struct i810fb_par *par = info->par; + u8 *edid = NULL; + + DPRINTK("i810-i2c: Probe DDC%i Bus\n", conn+1); + if (conn < par->ddc_num) { + edid = fb_ddc_read(&par->chan[conn].adapter); + } else { + const u8 *e = fb_firmware_edid(info->device); + + if (e != NULL) { + DPRINTK("i810-i2c: Getting EDID from BIOS\n"); + edid = kmemdup(e, EDID_LENGTH, GFP_KERNEL); + } + } + + *out_edid = edid; + + return (edid) ? 0 : 1; +} diff --git a/drivers/video/fbdev/i810/i810.h b/drivers/video/fbdev/i810/i810.h new file mode 100644 index 000000000..7b1c002bf --- /dev/null +++ b/drivers/video/fbdev/i810/i810.h @@ -0,0 +1,298 @@ +/*-*- linux-c -*- + * linux/drivers/video/i810.h -- Intel 810 General Definitions/Declarations + * + * Copyright (C) 2001 Antonino Daplas + * All Rights Reserved + * + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of this archive for + * more details. + */ + +#ifndef __I810_H__ +#define __I810_H__ + +#include +#include +#include +#include +#include +#include