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/media/rc/ir-sharp-decoder.c | 244 ++++++++++++++++++++++++++++++++++++ 1 file changed, 244 insertions(+) create mode 100644 drivers/media/rc/ir-sharp-decoder.c (limited to 'drivers/media/rc/ir-sharp-decoder.c') diff --git a/drivers/media/rc/ir-sharp-decoder.c b/drivers/media/rc/ir-sharp-decoder.c new file mode 100644 index 000000000..3311099cb --- /dev/null +++ b/drivers/media/rc/ir-sharp-decoder.c @@ -0,0 +1,244 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* ir-sharp-decoder.c - handle Sharp IR Pulse/Space protocol + * + * Copyright (C) 2013-2014 Imagination Technologies Ltd. + * + * Based on NEC decoder: + * Copyright (C) 2010 by Mauro Carvalho Chehab + */ + +#include +#include +#include "rc-core-priv.h" + +#define SHARP_NBITS 15 +#define SHARP_UNIT 40 /* us */ +#define SHARP_BIT_PULSE (8 * SHARP_UNIT) /* 320us */ +#define SHARP_BIT_0_PERIOD (25 * SHARP_UNIT) /* 1ms (680us space) */ +#define SHARP_BIT_1_PERIOD (50 * SHARP_UNIT) /* 2ms (1680us space) */ +#define SHARP_BIT_0_SPACE (17 * SHARP_UNIT) /* 680us space */ +#define SHARP_BIT_1_SPACE (42 * SHARP_UNIT) /* 1680us space */ +#define SHARP_ECHO_SPACE (1000 * SHARP_UNIT) /* 40 ms */ +#define SHARP_TRAILER_SPACE (125 * SHARP_UNIT) /* 5 ms (even longer) */ + +enum sharp_state { + STATE_INACTIVE, + STATE_BIT_PULSE, + STATE_BIT_SPACE, + STATE_TRAILER_PULSE, + STATE_ECHO_SPACE, + STATE_TRAILER_SPACE, +}; + +/** + * ir_sharp_decode() - Decode one Sharp pulse or space + * @dev: the struct rc_dev descriptor of the device + * @ev: the struct ir_raw_event descriptor of the pulse/space + * + * This function returns -EINVAL if the pulse violates the state machine + */ +static int ir_sharp_decode(struct rc_dev *dev, struct ir_raw_event ev) +{ + struct sharp_dec *data = &dev->raw->sharp; + u32 msg, echo, address, command, scancode; + + if (!is_timing_event(ev)) { + if (ev.overflow) + data->state = STATE_INACTIVE; + return 0; + } + + dev_dbg(&dev->dev, "Sharp decode started at state %d (%uus %s)\n", + data->state, ev.duration, TO_STR(ev.pulse)); + + switch (data->state) { + + case STATE_INACTIVE: + if (!ev.pulse) + break; + + if (!eq_margin(ev.duration, SHARP_BIT_PULSE, + SHARP_BIT_PULSE / 2)) + break; + + data->count = 0; + data->pulse_len = ev.duration; + data->state = STATE_BIT_SPACE; + return 0; + + case STATE_BIT_PULSE: + if (!ev.pulse) + break; + + if (!eq_margin(ev.duration, SHARP_BIT_PULSE, + SHARP_BIT_PULSE / 2)) + break; + + data->pulse_len = ev.duration; + data->state = STATE_BIT_SPACE; + return 0; + + case STATE_BIT_SPACE: + if (ev.pulse) + break; + + data->bits <<= 1; + if (eq_margin(data->pulse_len + ev.duration, SHARP_BIT_1_PERIOD, + SHARP_BIT_PULSE * 2)) + data->bits |= 1; + else if (!eq_margin(data->pulse_len + ev.duration, + SHARP_BIT_0_PERIOD, SHARP_BIT_PULSE * 2)) + break; + data->count++; + + if (data->count == SHARP_NBITS || + data->count == SHARP_NBITS * 2) + data->state = STATE_TRAILER_PULSE; + else + data->state = STATE_BIT_PULSE; + + return 0; + + case STATE_TRAILER_PULSE: + if (!ev.pulse) + break; + + if (!eq_margin(ev.duration, SHARP_BIT_PULSE, + SHARP_BIT_PULSE / 2)) + break; + + if (data->count == SHARP_NBITS) { + /* exp,chk bits should be 1,0 */ + if ((data->bits & 0x3) != 0x2 && + /* DENON variant, both chk bits 0 */ + (data->bits & 0x3) != 0x0) + break; + data->state = STATE_ECHO_SPACE; + } else { + data->state = STATE_TRAILER_SPACE; + } + return 0; + + case STATE_ECHO_SPACE: + if (ev.pulse) + break; + + if (!eq_margin(ev.duration, SHARP_ECHO_SPACE, + SHARP_ECHO_SPACE / 4)) + break; + + data->state = STATE_BIT_PULSE; + + return 0; + + case STATE_TRAILER_SPACE: + if (ev.pulse) + break; + + if (!geq_margin(ev.duration, SHARP_TRAILER_SPACE, + SHARP_BIT_PULSE / 2)) + break; + + /* Validate - command, ext, chk should be inverted in 2nd */ + msg = (data->bits >> 15) & 0x7fff; + echo = data->bits & 0x7fff; + if ((msg ^ echo) != 0x3ff) { + dev_dbg(&dev->dev, + "Sharp checksum error: received 0x%04x, 0x%04x\n", + msg, echo); + break; + } + + address = bitrev8((msg >> 7) & 0xf8); + command = bitrev8((msg >> 2) & 0xff); + + scancode = address << 8 | command; + dev_dbg(&dev->dev, "Sharp scancode 0x%04x\n", scancode); + + rc_keydown(dev, RC_PROTO_SHARP, scancode, 0); + data->state = STATE_INACTIVE; + return 0; + } + + dev_dbg(&dev->dev, "Sharp decode failed at count %d state %d (%uus %s)\n", + data->count, data->state, ev.duration, TO_STR(ev.pulse)); + data->state = STATE_INACTIVE; + return -EINVAL; +} + +static const struct ir_raw_timings_pd ir_sharp_timings = { + .header_pulse = 0, + .header_space = 0, + .bit_pulse = SHARP_BIT_PULSE, + .bit_space[0] = SHARP_BIT_0_SPACE, + .bit_space[1] = SHARP_BIT_1_SPACE, + .trailer_pulse = SHARP_BIT_PULSE, + .trailer_space = SHARP_ECHO_SPACE, + .msb_first = 1, +}; + +/** + * ir_sharp_encode() - Encode a scancode as a stream of raw events + * + * @protocol: protocol to encode + * @scancode: scancode to encode + * @events: array of raw ir events to write into + * @max: maximum size of @events + * + * Returns: The number of events written. + * -ENOBUFS if there isn't enough space in the array to fit the + * encoding. In this case all @max events will have been written. + */ +static int ir_sharp_encode(enum rc_proto protocol, u32 scancode, + struct ir_raw_event *events, unsigned int max) +{ + struct ir_raw_event *e = events; + int ret; + u32 raw; + + raw = (((bitrev8(scancode >> 8) >> 3) << 8) & 0x1f00) | + bitrev8(scancode); + ret = ir_raw_gen_pd(&e, max, &ir_sharp_timings, SHARP_NBITS, + (raw << 2) | 2); + if (ret < 0) + return ret; + + max -= ret; + + raw = (((bitrev8(scancode >> 8) >> 3) << 8) & 0x1f00) | + bitrev8(~scancode); + ret = ir_raw_gen_pd(&e, max, &ir_sharp_timings, SHARP_NBITS, + (raw << 2) | 1); + if (ret < 0) + return ret; + + return e - events; +} + +static struct ir_raw_handler sharp_handler = { + .protocols = RC_PROTO_BIT_SHARP, + .decode = ir_sharp_decode, + .encode = ir_sharp_encode, + .carrier = 38000, + .min_timeout = SHARP_ECHO_SPACE + SHARP_ECHO_SPACE / 4, +}; + +static int __init ir_sharp_decode_init(void) +{ + ir_raw_handler_register(&sharp_handler); + + pr_info("IR Sharp protocol handler initialized\n"); + return 0; +} + +static void __exit ir_sharp_decode_exit(void) +{ + ir_raw_handler_unregister(&sharp_handler); +} + +module_init(ir_sharp_decode_init); +module_exit(ir_sharp_decode_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("James Hogan "); +MODULE_DESCRIPTION("Sharp IR protocol decoder"); -- cgit v1.3.1