KVM: SEV: Do cache maintenance on the source VM during intra-host migrationgrafted

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 <fane@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20260923163721.1584779-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 304 insertions, 0 deletions

diff --git a/sound/hda/codecs/senarytech.c b/sound/hda/codecs/senarytech.c
new file mode 100644
index 000000000..3ee8bc0ea
--- /dev/null
+++ b/sound/hda/codecs/senarytech.c
@@ -0,0 +1,304 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * HD audio codec driver for Senary HDA audio codec
+ *
+ * Initially based on conexant.c
+ */
+
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <sound/core.h>
+#include <sound/jack.h>
+
+#include <sound/hda_codec.h>
+#include "hda_local.h"
+#include "hda_auto_parser.h"
+#include "hda_beep.h"
+#include "hda_jack.h"
+#include "generic.h"
+
+struct senary_spec {
+	struct hda_gen_spec gen;
+
+	/* extra EAPD pins */
+	unsigned int num_eapds;
+	hda_nid_t eapds[4];
+	bool dynamic_eapd;
+	hda_nid_t mute_led_eapd;
+
+	unsigned int parse_flags; /* flag for snd_hda_parse_pin_defcfg() */
+
+	int mute_led_polarity;
+	unsigned int gpio_led;
+	unsigned int gpio_mute_led_mask;
+	unsigned int gpio_mic_led_mask;
+};
+
+enum {
+	SENARY_FIXUP_PINCFG_DEFAULT,
+};
+
+static const struct hda_pintbl senary_pincfg_default[] = {
+	{ 0x16, 0x02211020 }, /* Headphone */
+	{ 0x17, 0x40f001f0 }, /* Not used */
+	{ 0x18, 0x05a1904d }, /* Mic */
+	{ 0x19, 0x02a1104e }, /* Headset Mic */
+	{ 0x1a, 0x01819030 }, /* Line-in */
+	{ 0x1d, 0x01014010 }, /* Line-out */
+	{}
+};
+
+static const struct hda_fixup senary_fixups[] = {
+	[SENARY_FIXUP_PINCFG_DEFAULT] = {
+		.type = HDA_FIXUP_PINS,
+		.v.pins = senary_pincfg_default,
+	},
+};
+
+/* Quirk table for specific machines can be added here */
+static const struct hda_quirk sn6186_fixups[] = {
+	{}
+};
+
+#ifdef CONFIG_SND_HDA_INPUT_BEEP
+/* additional beep mixers; private_value will be overwritten */
+static const struct snd_kcontrol_new senary_beep_mixer[] = {
+	HDA_CODEC_VOLUME_MONO("Beep Playback Volume", 0, 1, 0, HDA_OUTPUT),
+	HDA_CODEC_MUTE_BEEP_MONO("Beep Playback Switch", 0, 1, 0, HDA_OUTPUT),
+};
+
+static int set_beep_amp(struct senary_spec *spec, hda_nid_t nid,
+			int idx, int dir)
+{
+	struct snd_kcontrol_new *knew;
+	unsigned int beep_amp = HDA_COMPOSE_AMP_VAL(nid, 1, idx, dir);
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(senary_beep_mixer); i++) {
+		knew = snd_hda_gen_add_kctl(&spec->gen, NULL,
+					    &senary_beep_mixer[i]);
+		if (!knew)
+			return -ENOMEM;
+		knew->private_value = beep_amp;
+	}
+
+	spec->gen.beep_nid = nid;
+	return 0;
+}
+
+static int senary_auto_parse_beep(struct hda_codec *codec)
+{
+	struct senary_spec *spec = codec->spec;
+	hda_nid_t nid;
+
+	for_each_hda_codec_node(nid, codec)
+		if ((get_wcaps_type(get_wcaps(codec, nid)) == AC_WID_BEEP) &&
+			(get_wcaps(codec, nid) & (AC_WCAP_OUT_AMP | AC_WCAP_AMP_OVRD)))
+			return set_beep_amp(spec, nid, 0, HDA_OUTPUT);
+	return 0;
+}
+#else
+#define senary_auto_parse_beep(codec)	0
+#endif
+
+/* parse EAPDs */
+static void senary_auto_parse_eapd(struct hda_codec *codec)
+{
+	struct senary_spec *spec = codec->spec;
+	hda_nid_t nid;
+
+	for_each_hda_codec_node(nid, codec) {
+		if (get_wcaps_type(get_wcaps(codec, nid)) != AC_WID_PIN)
+			continue;
+		if (!(snd_hda_query_pin_caps(codec, nid) & AC_PINCAP_EAPD))
+			continue;
+		spec->eapds[spec->num_eapds++] = nid;
+		if (spec->num_eapds >= ARRAY_SIZE(spec->eapds))
+			break;
+	}
+}
+
+/* Hardware specific initialization verbs */
+static void senary_init_verb(struct hda_codec *codec)
+{
+	/* Vendor specific init sequence */
+	snd_hda_codec_write(codec, 0x1b, 0x0, 0x05a, 0xaa);
+	snd_hda_codec_write(codec, 0x1b, 0x0, 0x059, 0x48);
+	snd_hda_codec_write(codec, 0x1b, 0x0, 0x01b, 0x00);
+	snd_hda_codec_write(codec, 0x1b, 0x0, 0x01c, 0x00);
+
+	/* Override pin caps for headset mic */
+	snd_hda_override_pin_caps(codec, 0x19, 0x2124);
+}
+
+static void senary_auto_turn_eapd(struct hda_codec *codec, int num_pins,
+			      const hda_nid_t *pins, bool on)
+{
+	int i;
+
+	for (i = 0; i < num_pins; i++) {
+		snd_hda_codec_write(codec, pins[i], 0,
+				    AC_VERB_SET_EAPD_BTLENABLE,
+				    on ? 0x02 : 0);
+	}
+}
+
+/* turn on/off EAPD according to Master switch */
+static void senary_auto_vmaster_hook(void *private_data, int enabled)
+{
+	struct hda_codec *codec = private_data;
+	struct senary_spec *spec = codec->spec;
+
+	senary_auto_turn_eapd(codec, spec->num_eapds, spec->eapds, enabled);
+}
+
+static void senary_init_gpio_led(struct hda_codec *codec)
+{
+	struct senary_spec *spec = codec->spec;
+	unsigned int mask = spec->gpio_mute_led_mask | spec->gpio_mic_led_mask;
+
+	if (mask)
+		snd_hda_codec_set_gpio(codec, mask, mask, spec->gpio_led, 0);
+}
+
+static int senary_init(struct hda_codec *codec)
+{
+	struct senary_spec *spec = codec->spec;
+
+	snd_hda_gen_init(codec);
+	senary_init_gpio_led(codec);
+	senary_init_verb(codec);
+	if (!spec->dynamic_eapd)
+		senary_auto_turn_eapd(codec, spec->num_eapds, spec->eapds, true);
+	snd_hda_apply_fixup(codec, HDA_FIXUP_ACT_INIT);
+
+	return 0;
+}
+
+static void senary_shutdown(struct hda_codec *codec)
+{
+	struct senary_spec *spec = codec->spec;
+
+	/* Turn the problematic codec into D3 to avoid spurious noises
+	 * from the internal speaker during (and after) reboot
+	 */
+	senary_auto_turn_eapd(codec, spec->num_eapds, spec->eapds, false);
+}
+
+static void senary_remove(struct hda_codec *codec)
+{
+	senary_shutdown(codec);
+	snd_hda_gen_remove(codec);
+}
+
+static int senary_suspend(struct hda_codec *codec)
+{
+	senary_shutdown(codec);
+	return 0;
+}
+
+static int senary_probe(struct hda_codec *codec, const struct hda_device_id *id)
+{
+	struct senary_spec *spec;
+	int err;
+
+	codec_info(codec, "%s: BIOS auto-probing.\n", codec->core.chip_name);
+
+	spec = kzalloc_obj(*spec);
+	if (!spec)
+		return -ENOMEM;
+	snd_hda_gen_spec_init(&spec->gen);
+	codec->spec = spec;
+
+	senary_auto_parse_eapd(codec);
+	spec->gen.own_eapd_ctl = 1;
+
+	/* Setup fixups based on codec vendor ID */
+	switch (codec->core.vendor_id) {
+	case 0x1fa86186:
+		codec->pin_amp_workaround = 1;
+		spec->gen.mixer_nid = 0x15;
+		snd_hda_pick_fixup(codec, NULL, sn6186_fixups, senary_fixups);
+
+		/* If no specific quirk found, apply the default pin configuration */
+		if (codec->fixup_id == HDA_FIXUP_ID_NOT_SET)
+			codec->fixup_id = SENARY_FIXUP_PINCFG_DEFAULT;
+		break;
+	default:
+		snd_hda_pick_fixup(codec, NULL, sn6186_fixups, senary_fixups);
+		break;
+	}
+
+	snd_hda_apply_fixup(codec, HDA_FIXUP_ACT_PRE_PROBE);
+
+	/* Run hardware init verbs once during probe */
+	senary_init_verb(codec);
+
+	if (!spec->gen.vmaster_mute.hook)
+		spec->gen.vmaster_mute.hook = senary_auto_vmaster_hook;
+
+	err = snd_hda_parse_pin_defcfg(codec, &spec->gen.autocfg, NULL,
+				       spec->parse_flags);
+	if (err < 0)
+		goto error;
+
+	err = senary_auto_parse_beep(codec);
+	if (err < 0)
+		goto error;
+
+	err = snd_hda_gen_parse_auto_config(codec, &spec->gen.autocfg);
+	if (err < 0)
+		goto error;
+
+	/* Some laptops with Senary chips show stalls in S3 resume,
+	 * which falls into the single-cmd mode.
+	 * Better to make reset, then.
+	 */
+	if (!codec->bus->core.sync_write) {
+		codec_info(codec,
+			   "Enable sync_write for stable communication\n");
+		codec->bus->core.sync_write = 1;
+		codec->bus->allow_bus_reset = 1;
+	}
+
+	snd_hda_apply_fixup(codec, HDA_FIXUP_ACT_PROBE);
+
+	return 0;
+
+ error:
+	senary_remove(codec);
+	return err;
+}
+
+static const struct hda_codec_ops senary_codec_ops = {
+	.probe = senary_probe,
+	.remove = senary_remove,
+	.build_controls = snd_hda_gen_build_controls,
+	.build_pcms = snd_hda_gen_build_pcms,
+	.init = senary_init,
+	.unsol_event = snd_hda_jack_unsol_event,
+	.suspend = senary_suspend,
+	.check_power_status = snd_hda_gen_check_power_status,
+	.stream_pm = snd_hda_gen_stream_pm,
+};
+
+/*
+ */
+
+static const struct hda_device_id snd_hda_id_senary[] = {
+	HDA_CODEC_ID(0x1fa86186, "SN6186"),
+	{} /* terminator */
+};
+MODULE_DEVICE_TABLE(hdaudio, snd_hda_id_senary);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Senarytech HD-audio codec");
+
+static struct hda_codec_driver senary_driver = {
+	.id = snd_hda_id_senary,
+	.ops = &senary_codec_ops,
+};
+
+module_hda_codec_driver(senary_driver);