On Tue, Dec 14, 2021 at 2:33 AM Eric DeVolder <[email protected]> wrote:
>
> Ani, an inline response below.
> Thanks!
> eric
>
> On 12/10/21 08:09, Ani Sinha wrote:
> > On Thu, Dec 9, 2021 at 11:24 PM Eric DeVolder <[email protected]>
> > wrote:
> >>
> >> Ani, inline responses below. eric
> >>
> >> On 12/9/21 00:29, Ani Sinha wrote:
> >>> On Fri, Dec 3, 2021 at 12:39 AM Eric DeVolder <[email protected]>
> >>> wrote:
> >>>>
> >>>> This implements a PCI device for ACPI ERST. This implements the
> >>>> non-NVRAM "mode" of operation for ERST as it is supported by
> >>>> Linux and Windows.
> >>>
> >>> Few more comments on this patch ...
> >>>
> >>>>
> >>>> Signed-off-by: Eric DeVolder <[email protected]>
> >>>> ---
> >>>> hw/acpi/Kconfig | 6 +
> >>>> hw/acpi/erst.c | 836
> >>>> +++++++++++++++++++++++++++++++++++++++++++++++++++
> >>>> hw/acpi/meson.build | 1 +
> >>>> hw/acpi/trace-events | 15 +
> >>>> 4 files changed, 858 insertions(+)
> >>>> create mode 100644 hw/acpi/erst.c
> >>>>
> >>>> diff --git a/hw/acpi/Kconfig b/hw/acpi/Kconfig
> >>>> index 622b0b5..19caebd 100644
> >>>> --- a/hw/acpi/Kconfig
> >>>> +++ b/hw/acpi/Kconfig
> >>>> @@ -10,6 +10,7 @@ config ACPI_X86
> >>>> select ACPI_HMAT
> >>>> select ACPI_PIIX4
> >>>> select ACPI_PCIHP
> >>>> + select ACPI_ERST
> >>>>
> >>>> config ACPI_X86_ICH
> >>>> bool
> >>>> @@ -60,3 +61,8 @@ config ACPI_HW_REDUCED
> >>>> select ACPI
> >>>> select ACPI_MEMORY_HOTPLUG
> >>>> select ACPI_NVDIMM
> >>>> +
> >>>> +config ACPI_ERST
> >>>> + bool
> >>>> + default y
> >>>> + depends on ACPI && PCI
> >>>> diff --git a/hw/acpi/erst.c b/hw/acpi/erst.c
> >>>> new file mode 100644
> >>>> index 0000000..4304f55
> >>>> --- /dev/null
> >>>> +++ b/hw/acpi/erst.c
> >>>> @@ -0,0 +1,836 @@
> >>>> +/*
> >>>> + * ACPI Error Record Serialization Table, ERST, Implementation
> >>>> + *
> >>>> + * ACPI ERST introduced in ACPI 4.0, June 16, 2009.
> >>>> + * ACPI Platform Error Interfaces : Error Serialization
> >>>> + *
> >>>> + * Copyright (c) 2021 Oracle and/or its affiliates.
> >>>> + *
> >>>> + * SPDX-License-Identifier: GPL-2.0-or-later
> >>>> + */
> >>>> +
> >>>> +#include <sys/types.h>
> >>>> +#include <sys/stat.h>
> >>>> +#include <unistd.h>
> >>>> +
> >>>> +#include "qemu/osdep.h"
> >>>> +#include "qapi/error.h"
> >>>> +#include "hw/qdev-core.h"
> >>>> +#include "exec/memory.h"
> >>>> +#include "qom/object.h"
> >>>> +#include "hw/pci/pci.h"
> >>>> +#include "qom/object_interfaces.h"
> >>>> +#include "qemu/error-report.h"
> >>>> +#include "migration/vmstate.h"
> >>>> +#include "hw/qdev-properties.h"
> >>>> +#include "hw/acpi/acpi.h"
> >>>> +#include "hw/acpi/acpi-defs.h"
> >>>> +#include "hw/acpi/aml-build.h"
> >>>> +#include "hw/acpi/bios-linker-loader.h"
> >>>> +#include "exec/address-spaces.h"
> >>>> +#include "sysemu/hostmem.h"
> >>>> +#include "hw/acpi/erst.h"
> >>>> +#include "trace.h"
> >>>> +
> >>>> +/* ACPI 4.0: Table 17-16 Serialization Actions */
> >>>> +#define ACTION_BEGIN_WRITE_OPERATION 0x0
> >>>> +#define ACTION_BEGIN_READ_OPERATION 0x1
> >>>> +#define ACTION_BEGIN_CLEAR_OPERATION 0x2
> >>>> +#define ACTION_END_OPERATION 0x3
> >>>> +#define ACTION_SET_RECORD_OFFSET 0x4
> >>>> +#define ACTION_EXECUTE_OPERATION 0x5
> >>>> +#define ACTION_CHECK_BUSY_STATUS 0x6
> >>>> +#define ACTION_GET_COMMAND_STATUS 0x7
> >>>> +#define ACTION_GET_RECORD_IDENTIFIER 0x8
> >>>> +#define ACTION_SET_RECORD_IDENTIFIER 0x9
> >>>> +#define ACTION_GET_RECORD_COUNT 0xA
> >>>> +#define ACTION_BEGIN_DUMMY_WRITE_OPERATION 0xB
> >>>> +#define ACTION_RESERVED 0xC
> >>>> +#define ACTION_GET_ERROR_LOG_ADDRESS_RANGE 0xD
> >>>> +#define ACTION_GET_ERROR_LOG_ADDRESS_LENGTH 0xE
> >>>> +#define ACTION_GET_ERROR_LOG_ADDRESS_RANGE_ATTRIBUTES 0xF
> >>>> +#define ACTION_GET_EXECUTE_OPERATION_TIMINGS 0x10
> >>>> +
> >>>> +/* ACPI 4.0: Table 17-17 Command Status Definitions */
> >>>> +#define STATUS_SUCCESS 0x00
> >>>> +#define STATUS_NOT_ENOUGH_SPACE 0x01
> >>>> +#define STATUS_HARDWARE_NOT_AVAILABLE 0x02
> >>>> +#define STATUS_FAILED 0x03
> >>>> +#define STATUS_RECORD_STORE_EMPTY 0x04
> >>>> +#define STATUS_RECORD_NOT_FOUND 0x05
> >>>> +
> >>>> +
> >>>> +/* UEFI 2.1: Appendix N Common Platform Error Record */
> >>>> +#define UEFI_CPER_RECORD_MIN_SIZE 128U
> >>>> +#define UEFI_CPER_RECORD_LENGTH_OFFSET 20U
> >>>> +#define UEFI_CPER_RECORD_ID_OFFSET 96U
> >>>> +#define IS_UEFI_CPER_RECORD(ptr) \
> >>>> + (((ptr)[0] == 'C') && \
> >>>> + ((ptr)[1] == 'P') && \
> >>>> + ((ptr)[2] == 'E') && \
> >>>> + ((ptr)[3] == 'R'))
> >>>> +
> >>>> +/*
> >>>> + * NOTE that when accessing CPER fields within a record, memcpy()
> >>>> + * is utilized to avoid a possible misaligned access on the host.
> >>>> + */
> >>>> +
> >>>> +/*
> >>>> + * This implementation is an ACTION (cmd) and VALUE (data)
> >>>> + * interface consisting of just two 64-bit registers.
> >>>> + */
> >>>> +#define ERST_REG_SIZE (16UL)
> >>>> +#define ERST_ACTION_OFFSET (0UL) /* action (cmd) */
> >>>> +#define ERST_VALUE_OFFSET (8UL) /* argument/value (data) */
> >>>> +
> >>>> +/*
> >>>> + * ERST_RECORD_SIZE is the buffer size for exchanging ERST
> >>>> + * record contents. Thus, it defines the maximum record size.
> >>>> + * As this is mapped through a PCI BAR, it must be a power of
> >>>> + * two and larger than UEFI_CPER_RECORD_MIN_SIZE.
> >>>> + * The backing storage is divided into fixed size "slots",
> >>>> + * each ERST_RECORD_SIZE in length, and each "slot"
> >>>> + * storing a single record. No attempt at optimizing storage
> >>>> + * through compression, compaction, etc is attempted.
> >>>> + * NOTE that slot 0 is reserved for the backing storage header.
> >>>> + * Depending upon the size of the backing storage, additional
> >>>> + * slots will be part of the slot 0 header in order to account
> >>>> + * for a record_id for each available remaining slot.
> >>>> + */
> >>>> +/* 8KiB records, not too small, not too big */
> >>>> +#define ERST_RECORD_SIZE (8192UL)
> >>>> +
> >>>> +#define ACPI_ERST_MEMDEV_PROP "memdev"
> >>>> +#define ACPI_ERST_RECORD_SIZE_PROP "record_size"
> >>>> +
> >>>> +/*
> >>>> + * From the ACPI ERST spec sections:
> >>>> + * A record id of all 0s is used to indicate 'unspecified' record id.
> >>>> + * A record id of all 1s is used to indicate empty or end.
> >>>> + */
> >>>> +#define ERST_UNSPECIFIED_RECORD_ID (0UL)
> >>>> +#define ERST_EMPTY_END_RECORD_ID (~0UL)
> >>>> +#define ERST_EXECUTE_OPERATION_MAGIC 0x9CUL
> >>>> +#define ERST_IS_VALID_RECORD_ID(rid) \
> >>>> + ((rid != ERST_UNSPECIFIED_RECORD_ID) && \
> >>>> + (rid != ERST_EMPTY_END_RECORD_ID))
> >>>> +#define ERST_STORE_MAGIC 0x524F545354535245UL /* ERSTSTOR */
> >>>> +
> >>>
> >>> you might want to add a comment something like
> >>> /* please see erst.rst documentation for the details on this header
> >>> structure */
> >> done!
> >>
> >>>
> >>>> +typedef struct {
> >>>> + uint64_t magic;
> >>>> + uint32_t record_size;
> >>>> + uint32_t storage_offset; /* offset to record storage beyond header
> >>>> */
> >>>> + uint16_t version;
> >>>> + uint16_t reserved;
> >>>> + uint32_t record_count;
> >>>> + uint64_t map[]; /* contains record_ids, and position indicates
> >>>> index */
> >>>> +} __attribute__((packed)) ERSTStorageHeader;
> >>>> +
> >>>> +/*
> >>>> + * Object cast macro
> >>>> + */
> >>>> +#define ACPIERST(obj) \
> >>>> + OBJECT_CHECK(ERSTDeviceState, (obj), TYPE_ACPI_ERST)
> >>>> +
> >>>> +/*
> >>>> + * Main ERST device state structure
> >>>> + */
> >>>> +typedef struct {
> >>>> + PCIDevice parent_obj;
> >>>> +
> >>>> + /* Backend storage */
> >>>> + HostMemoryBackend *hostmem;
> >>>> + MemoryRegion *hostmem_mr;
> >>>> + uint32_t storage_size;
> >>>> + uint32_t default_record_size;
> >>>> +
> >>>> + /* Programming registers */
> >>>> + MemoryRegion iomem_mr;
> >>>> +
> >>>> + /* Exchange buffer */
> >>>> + MemoryRegion exchange_mr;
> >>>> +
> >>>> + /* Interface state */
> >>>> + uint8_t operation;
> >>>> + uint8_t busy_status;
> >>>> + uint8_t command_status;
> >>>> + uint32_t record_offset;
> >>>> + uint64_t reg_action;
> >>>> + uint64_t reg_value;
> >>>> + uint64_t record_identifier;
> >>>> + ERSTStorageHeader *header;
> >>>> + unsigned first_record_index;
> >>>> + unsigned last_record_index;
> >>>> + unsigned next_record_index;
> >>>> +
> >>>> +} ERSTDeviceState;
> >>>> +
> >>>> +/*******************************************************************/
> >>>> +/*******************************************************************/
> >>>> +
> >>>> +static uint8_t *get_nvram_ptr_by_index(ERSTDeviceState *s, unsigned
> >>>> index)
> >>>> +{
> >>>> + uint8_t *rc = NULL;
> >>>> + off_t offset = (index * le32_to_cpu(s->header->record_size));
> >>>> +
> >>>> + g_assert(offset < s->storage_size);
> >>>> +
> >>>> + rc = memory_region_get_ram_ptr(s->hostmem_mr);
> >>>> + rc += offset;
> >>>> +
> >>>> + return rc;
> >>>> +}
> >>>> +
> >>>> +static void make_erst_storage_header(ERSTDeviceState *s)
> >>>> +{
> >>>> + ERSTStorageHeader *header = s->header;
> >>>> + unsigned mapsz, headersz;
> >>>> +
> >>>> + header->magic = cpu_to_le64(ERST_STORE_MAGIC);
> >>>> + header->record_size = cpu_to_le32(s->default_record_size);
> >>>> + header->version = cpu_to_le16(0x0100);
> >>>> + header->reserved = cpu_to_le16(0x0000);
> >>>> +
> >>>> + /* Compute mapsize */
> >>>> + mapsz = s->storage_size / s->default_record_size;
> >>>> + mapsz *= sizeof(uint64_t);
> >>>> + /* Compute header+map size */
> >>>> + headersz = sizeof(ERSTStorageHeader) + mapsz;
> >>>> + /* Round up to nearest integer multiple of ERST_RECORD_SIZE */
> >>>> + headersz = QEMU_ALIGN_UP(headersz, s->default_record_size);
> >>>> + header->storage_offset = cpu_to_le32(headersz);
> >>>> +
> >>>> + /*
> >>>> + * The HostMemoryBackend initializes contents to zero,
> >>>> + * so all record_ids stashed in the map are zero'd.
> >>>> + * As well the record_count is zero. Properly initialized.
> >>>> + */
> >>>> +}
> >>>> +
> >>>> +static void check_erst_backend_storage(ERSTDeviceState *s, Error **errp)
> >>>> +{
> >>>> + ERSTStorageHeader *header;
> >>>> + uint32_t record_size;
> >>>> +
> >>>> + header = memory_region_get_ram_ptr(s->hostmem_mr);
> >>>> + s->header = header;
> >>>> +
> >>>> + /* Ensure pointer to header is 64-bit aligned */
> >>>> + g_assert(QEMU_PTR_IS_ALIGNED(header, sizeof(uint64_t)));
> >>>> +
> >>>> + /*
> >>>> + * Check if header is uninitialized; HostMemoryBackend inits to 0
> >>>> + */
> >>>> + if (le64_to_cpu(header->magic) == 0UL) {
> >>>> + make_erst_storage_header(s);
> >>>> + }
> >>>> +
> >>>> + /* Validity check record_size */
> >>>> + record_size = le32_to_cpu(header->record_size);
> >>>> + if (!(
> >>>> + (record_size) && /* non zero */
> >>>> + (record_size >= UEFI_CPER_RECORD_MIN_SIZE) &&
> >>>> + (((record_size - 1) & record_size) == 0) && /* is power of 2 */
> >>>> + (record_size >= 4096) /* PAGE_SIZE */
> >>>> + )) {
> >>>> + error_setg(errp, "ERST record_size %u is invalid", record_size);
> >>>> + }
> >>>> +
> >>>> + /* Validity check header */
> >>>> + if (!(
> >>>> + (le64_to_cpu(header->magic) == ERST_STORE_MAGIC) &&
> >>>> + ((le32_to_cpu(header->storage_offset) % record_size) == 0) &&
> >>>> + (le16_to_cpu(header->version) == 0x0100) &&
> >>>> + (le16_to_cpu(header->reserved) == 0)
> >>>> + )) {
> >>>> + error_setg(errp, "ERST backend storage header is invalid");
> >>>> + }
> >>>> +
> >>>> + /* Check storage_size against record_size */
> >>>> + if (((s->storage_size % record_size) != 0) ||
> >>>> + (record_size > s->storage_size)) {
> >>>> + error_setg(errp, "ACPI ERST requires storage size be multiple
> >>>> of "
> >>>> + "record size (%uKiB)", record_size);
> >>>> + }
> >>>> +
> >>>> + /* Compute offset of first and last record storage slot */
> >>>> + s->first_record_index = le32_to_cpu(header->storage_offset)
> >>>> + / record_size;
> >>>> + s->last_record_index = (s->storage_size / record_size);
> >>>> +}
> >>>> +
> >>>> +static void update_map_entry(ERSTDeviceState *s, unsigned index,
> >>>> + uint64_t record_id)
> >>>> +{
> >>>> + if (index < s->last_record_index) {
> >>>> + s->header->map[index] = cpu_to_le64(record_id);
> >>>> + }
> >>>> +}
> >>>> +
> >>>> +static unsigned allocate_erst_record(ERSTDeviceState *s)
> >>>> +{
> >>>> + unsigned rc = 0; /* 0 not a valid index */
> >>>> + unsigned index = s->first_record_index;
> >>>> +
> >>>> + for (; index < s->last_record_index; ++index) {
> >>>> + if (le64_to_cpu(s->header->map[index]) ==
> >>>> ERST_UNSPECIFIED_RECORD_ID) {
> >>>> + rc = index;
> >>>> + break;
> >>>> + }
> >>>> + }
> >>>> +
> >>>> + return rc;
> >>>> +}
> >>>> +
> >>>> +static unsigned lookup_erst_record(ERSTDeviceState *s,
> >>>> + uint64_t record_identifier)
> >>>> +{
> >>>> + unsigned rc = 0; /* 0 not a valid index */
> >>>> +
> >>>> + /* Find the record_identifier in the map */
> >>>> + if (record_identifier != ERST_UNSPECIFIED_RECORD_ID) {
> >>>> + /*
> >>>> + * Count number of valid records encountered, and
> >>>> + * short-circuit the loop if identifier not found
> >>>> + */
> >>>> + uint32_t record_count = le32_to_cpu(s->header->record_count);
> >>>> + unsigned count = 0;
> >>>> + unsigned index;
> >>>> + for (index = s->first_record_index; index <
> >>>> s->last_record_index &&
> >>>> + count < record_count; ++index) {
> >>>> + if (le64_to_cpu(s->header->map[index]) ==
> >>>> record_identifier) {
> >>>> + rc = index;
> >>>> + break;
> >>>> + }
> >>>> + if (le64_to_cpu(s->header->map[index]) !=
> >>>> + ERST_UNSPECIFIED_RECORD_ID) {
> >>>> + ++count;
> >>>> + }
> >>>> + }
> >>>> + }
> >>>> +
> >>>> + return rc;
> >>>> +}
> >>>> +
> >>>> +/*
> >>>> + * ACPI 4.0: 17.4.1.1 Serialization Actions, also see
> >>>> + * ACPI 4.0: 17.4.2.2 Operations - Reading 6.c and 2.c
> >>>> + */
> >>>> +static unsigned get_next_record_identifier(ERSTDeviceState *s,
> >>>> + uint64_t *record_identifier, bool first)
> >>>> +{
> >>>> + unsigned found = 0;
> >>>> + unsigned index;
> >>>> +
> >>>> + /* For operations needing to return 'first' record identifer */
> >>>> + if (first) {
> >>>> + /* Reset initial index to beginning */
> >>>> + s->next_record_index = s->first_record_index;
> >>>> + }
> >>>> + index = s->next_record_index;
> >>>> +
> >>>> + *record_identifier = ERST_EMPTY_END_RECORD_ID;
> >>>> +
> >>>> + if (le32_to_cpu(s->header->record_count)) {
> >>>> + for (; index < s->last_record_index; ++index) {
> >>>> + if (le64_to_cpu(s->header->map[index]) !=
> >>>> + ERST_UNSPECIFIED_RECORD_ID) {
> >>>> + /* where to start next time */
> >>>> + s->next_record_index = index + 1;
> >>>> + *record_identifier =
> >>>> le64_to_cpu(s->header->map[index]);
> >>>> + found = 1;
> >>>> + break;
> >>>> + }
> >>>> + }
> >>>> + }
> >>>> + if (!found) {
> >>>> + /* at end (ie scan complete), reset */
> >>>> + s->next_record_index = s->first_record_index;
> >>>> + }
> >>>> +
> >>>> + return STATUS_SUCCESS;
> >>>> +}
> >>>> +
> >>>> +/* ACPI 4.0: 17.4.2.3 Operations - Clearing */
> >>>> +static unsigned clear_erst_record(ERSTDeviceState *s)
> >>>> +{
> >>>> + unsigned rc = STATUS_RECORD_NOT_FOUND;
> >>>> + unsigned index;
> >>>> +
> >>>> + /* Check for valid record identifier */
> >>>> + if (!ERST_IS_VALID_RECORD_ID(s->record_identifier)) {
> >>>> + return STATUS_FAILED;
> >>>> + }
> >>>> +
> >>>> + index = lookup_erst_record(s, s->record_identifier);
> >>>> + if (index) {
> >>>> + /* No need to wipe record, just invalidate its map entry */
> >>>> + uint32_t record_count;
> >>>> + update_map_entry(s, index, ERST_UNSPECIFIED_RECORD_ID);
> >>>> + record_count = le32_to_cpu(s->header->record_count);
> >>>> + record_count -= 1;
> >>>> + s->header->record_count = cpu_to_le32(record_count);
> >>>> + rc = STATUS_SUCCESS;
> >>>> + }
> >>>> +
> >>>> + return rc;
> >>>> +}
> >>>> +
> >>>> +/* ACPI 4.0: 17.4.2.2 Operations - Reading */
> >>>> +static unsigned read_erst_record(ERSTDeviceState *s)
> >>>> +{
> >>>> + unsigned rc = STATUS_RECORD_NOT_FOUND;
> >>>> + unsigned exchange_length;
> >>>> + unsigned index;
> >>>> +
> >>>> + /* Check if backend storage is empty */
> >>>> + if (le32_to_cpu(s->header->record_count) == 0) {
> >>>> + return STATUS_RECORD_STORE_EMPTY;
> >>>> + }
> >>>> +
> >>>> + exchange_length = memory_region_size(&s->exchange_mr);
> >>>> +
> >>>> + /* Check for record identifier of all 0s */
> >>>> + if (s->record_identifier == ERST_UNSPECIFIED_RECORD_ID) {
> >>>> + /* Set to 'first' record in storage */
> >>>> + get_next_record_identifier(s, &s->record_identifier, true);
> >>>> + /* record_identifier is now a valid id, or all 1s */
> >>>> + }
> >>>> +
> >>>> + /* Check for record identifier of all 1s */
> >>>> + if (s->record_identifier == ERST_EMPTY_END_RECORD_ID) {
> >>>> + return STATUS_FAILED;
> >>>> + }
> >>>> +
> >>>> + /* Validate record_offset */
> >>>> + if (s->record_offset > (exchange_length -
> >>>> UEFI_CPER_RECORD_MIN_SIZE)) {
> >>>> + return STATUS_FAILED;
> >>>> + }
> >>>> +
> >>>> + index = lookup_erst_record(s, s->record_identifier);
> >>>> + if (index) {
> >>>> + uint8_t *nvram;
> >>>> + uint8_t *exchange;
> >>>> + uint32_t record_length;
> >>>> +
> >>>> + /* Obtain pointer to the exchange buffer */
> >>>> + exchange = memory_region_get_ram_ptr(&s->exchange_mr);
> >>>> + exchange += s->record_offset;
> >>>> + /* Obtain pointer to slot in storage */
> >>>> + nvram = get_nvram_ptr_by_index(s, index);
> >>>> + /* Validate CPER record_length */
> >>>> + memcpy((uint8_t *)&record_length,
> >>>> + &nvram[UEFI_CPER_RECORD_LENGTH_OFFSET],
> >>>> + sizeof(uint32_t));
> >>>> + record_length = le32_to_cpu(record_length);
> >>>> + if (record_length < UEFI_CPER_RECORD_MIN_SIZE) {
> >>>> + rc = STATUS_FAILED;
> >>>> + }
> >>>> + if ((s->record_offset + record_length) > exchange_length) {
> >>>> + rc = STATUS_FAILED;
> >>>> + }
> >>>> + /* If all is ok, copy the record to the exchange buffer */
> >>>> + if (rc != STATUS_FAILED) {
> >>>> + memcpy(exchange, nvram, record_length);
> >>>> + rc = STATUS_SUCCESS;
> >>>> + }
> >>>> + } else {
> >>>
> >>> I wonder if it is wise to return the next record id if the record is
> >>> not found. Should we simply return STATUS_FAILED here as well?
> >>
> >> Actually, this is per the spec. ACPI Spec 4.0 17.4.2.2 (or ACPI Spec 6.3
> >> 18.5.2.2) "Reading", see
> >> "The steps performed by the platform ...", section 2.c, calls for locating
> >> the 'first' identifier.
> >
> > yes you are correct on this one.
> >
> >>
> >> I left a reference comment in the code.
> >>
> >>>
> >>>> + /* Set to 'first' record in storage */
> >>>> + get_next_record_identifier(s, &s->record_identifier, true);
> >>>> + }
> >>>> +
> >>>> + return rc;
> >>>> +}
> >>>> +
> >>>> +/* ACPI 4.0: 17.4.2.1 Operations - Writing */
> >>>> +static unsigned write_erst_record(ERSTDeviceState *s)
> >>>> +{
> >>>> + unsigned rc = STATUS_FAILED;
> >>>> + unsigned exchange_length;
> >>>> + unsigned index;
> >>>> + uint64_t record_identifier;
> >>>> + uint32_t record_length;
> >>>> + uint8_t *exchange;
> >>>> + uint8_t *nvram = NULL;
> >>>> + bool record_found = false;
> >>>> +
> >>>> + exchange_length = memory_region_size(&s->exchange_mr);
> >>>> +
> >>>> + /* Validate record_offset */
> >>>> + if (s->record_offset > (exchange_length -
> >>>> UEFI_CPER_RECORD_MIN_SIZE)) {
> >>>> + return STATUS_FAILED;
> >>>> + }
> >>>> +
> >>>> + /* Obtain pointer to record in the exchange buffer */
> >>>> + exchange = memory_region_get_ram_ptr(&s->exchange_mr);
> >>>> + exchange += s->record_offset;
> >>>> +
> >>>> + /* Validate CPER record_length */
> >>>> + memcpy((uint8_t *)&record_length,
> >>>> &exchange[UEFI_CPER_RECORD_LENGTH_OFFSET],
> >>>> + sizeof(uint32_t));
> >>>> + record_length = le32_to_cpu(record_length);
> >>>> + if (record_length < UEFI_CPER_RECORD_MIN_SIZE) {
> >>>> + return STATUS_FAILED;
> >>>> + }
> >>>> + if ((s->record_offset + record_length) > exchange_length) {
> >>>> + return STATUS_FAILED;
> >>>> + }
> >>>> +
> >>>> + /* Extract record identifier */
> >>>> + memcpy((uint8_t *)&record_identifier,
> >>>> &exchange[UEFI_CPER_RECORD_ID_OFFSET],
> >>>> + sizeof(uint64_t));
> >>>> + record_identifier = le64_to_cpu(record_identifier);
> >>>> +
> >>>> + /* Check for valid record identifier */
> >>>> + if (!ERST_IS_VALID_RECORD_ID(record_identifier)) {
> >>>> + return STATUS_FAILED;
> >>>> + }
> >>>> +
> >>>> + index = lookup_erst_record(s, record_identifier);
> >>>> + if (index) {
> >>>> + /* Record found, overwrite existing record */
> >>>> + nvram = get_nvram_ptr_by_index(s, index);
> >>>> + record_found = true;
> >>>> + } else {
> >>>> + /* Record not found, not an overwrite, allocate for write */
> >>>> + index = allocate_erst_record(s);
> >>>> + if (index) {
> >>>> + nvram = get_nvram_ptr_by_index(s, index);
> >>>> + } else {
> >>>> + rc = STATUS_NOT_ENOUGH_SPACE;
> >>>
> >>> /* all slots are occupied */
> >> done!
> >>
> >>>
> >>>> + }
> >>>> + }
> >>>> + if (nvram) {
> >>>> + /* Write the record into the slot */
> >>>> + memcpy(nvram, exchange, record_length);
> >>>> + memset(nvram + record_length, exchange_length - record_length,
> >>>> 0xFF);
> >>>> + /* If a new record, increment the record_count */
> >>>> + if (!record_found) {
> >>>> + uint32_t record_count;
> >>>> + record_count = le32_to_cpu(s->header->record_count);
> >>>> + record_count += 1; /* writing new record */
> >>>> + s->header->record_count = cpu_to_le32(record_count);
> >>>> + }
> >>>> + update_map_entry(s, index, record_identifier);
> >>>> + rc = STATUS_SUCCESS;
> >>>> + }
> >>>> +
> >>>> + return rc;
> >>>> +}
> >>>> +
> >>>> +/*******************************************************************/
> >>>> +
> >>>> +static uint64_t erst_rd_reg64(hwaddr addr,
> >>>> + uint64_t reg, unsigned size)
> >>>> +{
> >>>> + uint64_t rdval;
> >>>> + uint64_t mask;
> >>>> + unsigned shift;
> >>>> +
> >>>> + if (size == sizeof(uint64_t)) {
> >>>> + /* 64b access */
> >>>> + mask = 0xFFFFFFFFFFFFFFFFUL;
> >>>> + shift = 0;
> >>>> + } else {
> >>>> + /* 32b access */
> >>>> + mask = 0x00000000FFFFFFFFUL;
> >>>> + shift = ((addr & 0x4) == 0x4) ? 32 : 0;
> >>>> + }
> >>>> +
> >>>> + rdval = reg;
> >>>> + rdval >>= shift;
> >>>> + rdval &= mask;
> >>>> +
> >>>> + return rdval;
> >>>> +}
> >>>> +
> >>>> +static uint64_t erst_wr_reg64(hwaddr addr,
> >>>> + uint64_t reg, uint64_t val, unsigned size)
> >>>> +{
> >>>> + uint64_t wrval;
> >>>> + uint64_t mask;
> >>>> + unsigned shift;
> >>>> +
> >>>> + if (size == sizeof(uint64_t)) {
> >>>> + /* 64b access */
> >>>> + mask = 0xFFFFFFFFFFFFFFFFUL;
> >>>> + shift = 0;
> >>>> + } else {
> >>>> + /* 32b access */
> >>>> + mask = 0x00000000FFFFFFFFUL;
> >>>> + shift = ((addr & 0x4) == 0x4) ? 32 : 0;
> >>>> + }
> >>>> +
> >>>> + val &= mask;
> >>>> + val <<= shift;
> >>>> + mask <<= shift;
> >>>> + wrval = reg;
> >>>> + wrval &= ~mask;
> >>>> + wrval |= val;
> >>>> +
> >>>> + return wrval;
> >>>> +}
> >>>> +
> >>>> +static void erst_reg_write(void *opaque, hwaddr addr,
> >>>> + uint64_t val, unsigned size)
> >>>> +{
> >>>> + ERSTDeviceState *s = (ERSTDeviceState *)opaque;
> >>>> +
> >>>> + /*
> >>>> + * NOTE: All actions/operations/side effects happen on the WRITE,
> >>>> + * by this implementation's design. The READs simply return the
> >>>> + * reg_value contents.
> >>>> + */
> >>>> + trace_acpi_erst_reg_write(addr, val, size);
> >>>> +
> >>>> + switch (addr) {
> >>>> + case ERST_VALUE_OFFSET + 0:
> >>>> + case ERST_VALUE_OFFSET + 4:
> >>>> + s->reg_value = erst_wr_reg64(addr, s->reg_value, val, size);
> >>>> + break;
> >>>> + case ERST_ACTION_OFFSET + 0:
> >>>> + /*
> >>>> + * NOTE: all valid values written to this register are of the
> >>>> + * ACTION_* variety. Thus there is no need to make this a 64-bit
> >>>> + * register, 32-bits is appropriate. As such
> >>>> ERST_ACTION_OFFSET+4
> >>>> + * is not needed.
> >>>> + */
> >>>> + switch (val) {
> >>>> + case ACTION_BEGIN_WRITE_OPERATION:
> >>>> + case ACTION_BEGIN_READ_OPERATION:
> >>>> + case ACTION_BEGIN_CLEAR_OPERATION:
> >>>> + case ACTION_BEGIN_DUMMY_WRITE_OPERATION:
> >>>> + case ACTION_END_OPERATION:
> >>>> + s->operation = val;
> >>>> + break;
> >>>> + case ACTION_SET_RECORD_OFFSET:
> >>>> + s->record_offset = s->reg_value;
> >>>> + break;
> >>>> + case ACTION_EXECUTE_OPERATION:
> >>>> + if ((uint8_t)s->reg_value == ERST_EXECUTE_OPERATION_MAGIC) {
> >>>> + s->busy_status = 1;
> >>>> + switch (s->operation) {
> >>>> + case ACTION_BEGIN_WRITE_OPERATION:
> >>>> + s->command_status = write_erst_record(s);
> >>>> + break;
> >>>> + case ACTION_BEGIN_READ_OPERATION:
> >>>> + s->command_status = read_erst_record(s);
> >>>> + break;
> >>>> + case ACTION_BEGIN_CLEAR_OPERATION:
> >>>> + s->command_status = clear_erst_record(s);
> >>>> + break;
> >>>> + case ACTION_BEGIN_DUMMY_WRITE_OPERATION:
> >>>> + s->command_status = STATUS_SUCCESS;
> >>>> + break;
> >>>> + case ACTION_END_OPERATION:
> >>>> + s->command_status = STATUS_SUCCESS;
> >>>> + break;
> >>>> + default:
> >>>> + s->command_status = STATUS_FAILED;
> >>>
> >>> Should this be something like STATUS_NOT_SUPPORTED?
> >> Throughout I've been exclusively using the status codes as defined in the
> >> spec:
> >> Success, Not Enough Space, Hardware Not Available, Failed, Record Store
> >> Empty, Record Not Found.
> >
> > yes sadly the spec does not have an equivalent of EINVAL or ENOTSUPP.
> >
> >>
> >> Failed seems to be an appropriate response.
> >
> > should we simply assert() on these cases for now (unless spec
> > explicitly says otherwise) ?
>
> I've re-examined the spec and it does not address this situation, that I can
> tell
>
> However, an assert() seems like a drastic measure (as I understand it, the
> assert would kill the guest).
>
> In theory we should never encounter this situation, as we have essentially
> provided a closed system
> with the ACPI table perfectly matching the capabilities of the hardware,
> and/or vice versa. I then
> suppose it becomes a matter if something malicious is happening. In that
> case, it better to assert()
> and kill the guest (essentiallyl a denial of service attack?), or just FAIL
> and make this
> "uninteresting" to the attacker?
>
> It seems to me that FAIL provides a better response.
I have reconsidered this and I think instead of crashing the process,
FAIL is indeed the better response.
You can fix this if you are spinning up a new version or I can fix it
once your patch has been pushed.
>
> >
> >>
> >>>
> >>>> + break;
> >>>> + }
> >>>> + s->busy_status = 0;
> >>>> + }
> >>>> + break;
> >>>> + case ACTION_CHECK_BUSY_STATUS:
> >>>> + s->reg_value = s->busy_status;
> >>>> + break;
> >>>> + case ACTION_GET_COMMAND_STATUS:
> >>>> + s->reg_value = s->command_status;
> >>>> + break;
> >>>> + case ACTION_GET_RECORD_IDENTIFIER:
> >>>> + s->command_status = get_next_record_identifier(s,
> >>>> + &s->reg_value, false);
> >>>> + break;
> >>>> + case ACTION_SET_RECORD_IDENTIFIER:
> >>>> + s->record_identifier = s->reg_value;
> >>>> + break;
> >>>> + case ACTION_GET_RECORD_COUNT:
> >>>> + s->reg_value = le32_to_cpu(s->header->record_count);
> >>>> + break;
> >>>> + case ACTION_GET_ERROR_LOG_ADDRESS_RANGE:
> >>>> + s->reg_value = (hwaddr)pci_get_bar_addr(PCI_DEVICE(s), 1);
> >>>> + break;
> >>>> + case ACTION_GET_ERROR_LOG_ADDRESS_LENGTH:
> >>>> + s->reg_value = le32_to_cpu(s->header->record_size);
> >>>> + break;
> >>>> + case ACTION_GET_ERROR_LOG_ADDRESS_RANGE_ATTRIBUTES:
> >>>> + s->reg_value = 0x0; /* intentional, not NVRAM mode */
> >>>> + break;
> >>>> + case ACTION_GET_EXECUTE_OPERATION_TIMINGS:
> >>>> + s->reg_value =
> >>>> + (100ULL << 32) | /* 100us max time */
> >>>> + (10ULL << 0) ; /* 10us min time */
> >>>> + break;
> >>>> + default:
> >>>> + /* Unknown action/command, NOP */
> >>>
> >>> maybe add some tracing here in case guests are going bad mmio writes?
> >> At the top of this function is a trace that produces information on all
> >> writes.
> >
> > OK cool.
> >
> >>
> >>>
> >>>> + break;
> >>>> + }
> >>>> + break;
> >>>> + default:
> >>>> + /* This should not happen, but if it does, NOP */
> >>>> + break;
> >>>> + }
> >>>> +}
> >>>> +
> >>>> +static uint64_t erst_reg_read(void *opaque, hwaddr addr,
> >>>> + unsigned size)
> >>>> +{
> >>>> + ERSTDeviceState *s = (ERSTDeviceState *)opaque;
> >>>> + uint64_t val = 0;
> >>>> +
> >>>> + switch (addr) {
> >>>> + case ERST_ACTION_OFFSET + 0:
> >>>> + case ERST_ACTION_OFFSET + 4:
> >>>> + val = erst_rd_reg64(addr, s->reg_action, size);
> >>>> + break;
> >>>> + case ERST_VALUE_OFFSET + 0:
> >>>> + case ERST_VALUE_OFFSET + 4:
> >>>> + val = erst_rd_reg64(addr, s->reg_value, size);
> >>>> + break;
> >>>> + default:
> >>>> + break;
> >>>> + }
> >>>> + trace_acpi_erst_reg_read(addr, val, size);
> >>>> + return val;
> >>>> +}
> >>>> +
> >>>> +static const MemoryRegionOps erst_reg_ops = {
> >>>> + .read = erst_reg_read,
> >>>> + .write = erst_reg_write,
> >>>> + .endianness = DEVICE_NATIVE_ENDIAN,
> >>>> +};
> >>>> +
> >>>> +/*******************************************************************/
> >>>> +/*******************************************************************/
> >>>> +static int erst_post_load(void *opaque, int version_id)
> >>>> +{
> >>>> + ERSTDeviceState *s = opaque;
> >>>> +
> >>>> + /* Recompute pointer to header */
> >>>> + s->header = (ERSTStorageHeader *)get_nvram_ptr_by_index(s, 0);
> >>>> + trace_acpi_erst_post_load(s->header,
> >>>> le32_to_cpu(s->header->record_size));
> >>>> +
> >>>> + return 0;
> >>>> +}
> >>>> +
> >>>> +static const VMStateDescription erst_vmstate = {
> >>>> + .name = "acpi-erst",
> >>>> + .version_id = 1,
> >>>> + .minimum_version_id = 1,
> >>>> + .post_load = erst_post_load,
> >>>> + .fields = (VMStateField[]) {
> >>>> + VMSTATE_UINT8(operation, ERSTDeviceState),
> >>>> + VMSTATE_UINT8(busy_status, ERSTDeviceState),
> >>>> + VMSTATE_UINT8(command_status, ERSTDeviceState),
> >>>> + VMSTATE_UINT32(record_offset, ERSTDeviceState),
> >>>> + VMSTATE_UINT64(reg_action, ERSTDeviceState),
> >>>> + VMSTATE_UINT64(reg_value, ERSTDeviceState),
> >>>> + VMSTATE_UINT64(record_identifier, ERSTDeviceState),
> >>>> + VMSTATE_UINT32(next_record_index, ERSTDeviceState),
> >>>> + VMSTATE_END_OF_LIST()
> >>>> + }
> >>>> +};
> >>>> +
> >>>> +static void erst_realizefn(PCIDevice *pci_dev, Error **errp)
> >>>> +{
> >>>> + ERSTDeviceState *s = ACPIERST(pci_dev);
> >>>> +
> >>>> + trace_acpi_erst_realizefn_in();
> >>>> +
> >>>> + if (!s->hostmem) {
> >>>> + error_setg(errp, "'" ACPI_ERST_MEMDEV_PROP "' property is not
> >>>> set");
> >>>> + return;
> >>>> + } else if (host_memory_backend_is_mapped(s->hostmem)) {
> >>>> + error_setg(errp, "can't use already busy memdev: %s",
> >>>> +
> >>>> object_get_canonical_path_component(OBJECT(s->hostmem)));
> >>>> + return;
> >>>> + }
> >>>> +
> >>>> + s->hostmem_mr = host_memory_backend_get_memory(s->hostmem);
> >>>> +
> >>>> + /* HostMemoryBackend size will be multiple of PAGE_SIZE */
> >>>> + s->storage_size = object_property_get_int(OBJECT(s->hostmem),
> >>>> "size", errp);
> >>>> +
> >>>> + /* Initialize backend storage and record_count */
> >>>> + check_erst_backend_storage(s, errp);
> >>>> +
> >>>> + /* BAR 0: Programming registers */
> >>>> + memory_region_init_io(&s->iomem_mr, OBJECT(pci_dev), &erst_reg_ops,
> >>>> s,
> >>>> + TYPE_ACPI_ERST, ERST_REG_SIZE);
> >>>> + pci_register_bar(pci_dev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY,
> >>>> &s->iomem_mr);
> >>>> +
> >>>> + /* BAR 1: Exchange buffer memory */
> >>>> + memory_region_init_ram(&s->exchange_mr, OBJECT(pci_dev),
> >>>> + "erst.exchange",
> >>>> + le32_to_cpu(s->header->record_size), errp);
> >>>> + pci_register_bar(pci_dev, 1, PCI_BASE_ADDRESS_SPACE_MEMORY,
> >>>> + &s->exchange_mr);
> >>>> +
> >>>> + /* Include the backend storage in the migration stream */
> >>>> + vmstate_register_ram_global(s->hostmem_mr);
> >>>> +
> >>>> + trace_acpi_erst_realizefn_out(s->storage_size);
> >>>> +}
> >>>> +
> >>>> +static void erst_reset(DeviceState *dev)
> >>>> +{
> >>>> + ERSTDeviceState *s = ACPIERST(dev);
> >>>> +
> >>>> + trace_acpi_erst_reset_in(le32_to_cpu(s->header->record_count));
> >>>> + s->operation = 0;
> >>>> + s->busy_status = 0;
> >>>> + s->command_status = STATUS_SUCCESS;
> >>>> + s->record_identifier = ERST_UNSPECIFIED_RECORD_ID;
> >>>> + s->record_offset = 0;
> >>>> + s->next_record_index = s->first_record_index;
> >>>> + /* NOTE: first/last_record_index are computed only once */
> >>>> + trace_acpi_erst_reset_out(le32_to_cpu(s->header->record_count));
> >>>> +}
> >>>> +
> >>>> +static Property erst_properties[] = {
> >>>> + DEFINE_PROP_LINK(ACPI_ERST_MEMDEV_PROP, ERSTDeviceState, hostmem,
> >>>> + TYPE_MEMORY_BACKEND, HostMemoryBackend *),
> >>>> + DEFINE_PROP_UINT32(ACPI_ERST_RECORD_SIZE_PROP, ERSTDeviceState,
> >>>> + default_record_size, ERST_RECORD_SIZE),
> >>>> + DEFINE_PROP_END_OF_LIST(),
> >>>> +};
> >>>> +
> >>>> +static void erst_class_init(ObjectClass *klass, void *data)
> >>>> +{
> >>>> + DeviceClass *dc = DEVICE_CLASS(klass);
> >>>> + PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
> >>>> +
> >>>> + trace_acpi_erst_class_init_in();
> >>>> + k->realize = erst_realizefn;
> >>>> + k->vendor_id = PCI_VENDOR_ID_REDHAT;
> >>>> + k->device_id = PCI_DEVICE_ID_REDHAT_ACPI_ERST;
> >>>> + k->revision = 0x00;
> >>>> + k->class_id = PCI_CLASS_OTHERS;
> >>>> + dc->reset = erst_reset;
> >>>> + dc->vmsd = &erst_vmstate;
> >>>> + dc->user_creatable = true;
> >>>> + dc->hotpluggable = false;
> >>>> + device_class_set_props(dc, erst_properties);
> >>>> + dc->desc = "ACPI Error Record Serialization Table (ERST) device";
> >>>> + set_bit(DEVICE_CATEGORY_MISC, dc->categories);
> >>>> + trace_acpi_erst_class_init_out();
> >>>> +}
> >>>> +
> >>>> +static const TypeInfo erst_type_info = {
> >>>> + .name = TYPE_ACPI_ERST,
> >>>> + .parent = TYPE_PCI_DEVICE,
> >>>> + .class_init = erst_class_init,
> >>>> + .instance_size = sizeof(ERSTDeviceState),
> >>>> + .interfaces = (InterfaceInfo[]) {
> >>>> + { INTERFACE_CONVENTIONAL_PCI_DEVICE },
> >>>> + { }
> >>>> + }
> >>>> +};
> >>>> +
> >>>> +static void erst_register_types(void)
> >>>> +{
> >>>> + type_register_static(&erst_type_info);
> >>>> +}
> >>>> +
> >>>> +type_init(erst_register_types)
> >>>> diff --git a/hw/acpi/meson.build b/hw/acpi/meson.build
> >>>> index adf6347..f5b2298 100644
> >>>> --- a/hw/acpi/meson.build
> >>>> +++ b/hw/acpi/meson.build
> >>>> @@ -22,6 +22,7 @@ acpi_ss.add(when: 'CONFIG_ACPI_PCIHP', if_true:
> >>>> files('pcihp.c'))
> >>>> acpi_ss.add(when: 'CONFIG_ACPI_PCIHP', if_false:
> >>>> files('acpi-pci-hotplug-stub.c'))
> >>>> acpi_ss.add(when: 'CONFIG_ACPI_VIOT', if_true: files('viot.c'))
> >>>> acpi_ss.add(when: 'CONFIG_ACPI_X86_ICH', if_true: files('ich9.c',
> >>>> 'tco.c'))
> >>>> +acpi_ss.add(when: 'CONFIG_ACPI_ERST', if_true: files('erst.c'))
> >>>> acpi_ss.add(when: 'CONFIG_IPMI', if_true: files('ipmi.c'), if_false:
> >>>> files('ipmi-stub.c'))
> >>>> acpi_ss.add(when: 'CONFIG_PC', if_false: files('acpi-x86-stub.c'))
> >>>> acpi_ss.add(when: 'CONFIG_TPM', if_true: files('tpm.c'))
> >>>> diff --git a/hw/acpi/trace-events b/hw/acpi/trace-events
> >>>> index 974d770..2250126 100644
> >>>> --- a/hw/acpi/trace-events
> >>>> +++ b/hw/acpi/trace-events
> >>>> @@ -55,3 +55,18 @@ piix4_gpe_writeb(uint64_t addr, unsigned width,
> >>>> uint64_t val) "addr: 0x%" PRIx64
> >>>> # tco.c
> >>>> tco_timer_reload(int ticks, int msec) "ticks=%d (%d ms)"
> >>>> tco_timer_expired(int timeouts_no, bool strap, bool no_reboot)
> >>>> "timeouts_no=%d no_reboot=%d/%d"
> >>>> +
> >>>> +# erst.c
> >>>> +acpi_erst_reg_write(uint64_t addr, uint64_t val, unsigned size) "addr:
> >>>> 0x%04" PRIx64 " <== 0x%016" PRIx64 " (size: %u)"
> >>>> +acpi_erst_reg_read(uint64_t addr, uint64_t val, unsigned size) " addr:
> >>>> 0x%04" PRIx64 " ==> 0x%016" PRIx64 " (size: %u)"
> >>>> +acpi_erst_mem_write(uint64_t addr, uint64_t val, unsigned size) "addr:
> >>>> 0x%06" PRIx64 " <== 0x%016" PRIx64 " (size: %u)"
> >>>> +acpi_erst_mem_read(uint64_t addr, uint64_t val, unsigned size) " addr:
> >>>> 0x%06" PRIx64 " ==> 0x%016" PRIx64 " (size: %u)"
> >>>> +acpi_erst_pci_bar_0(uint64_t addr) "BAR0: 0x%016" PRIx64
> >>>> +acpi_erst_pci_bar_1(uint64_t addr) "BAR1: 0x%016" PRIx64
> >>>> +acpi_erst_realizefn_in(void)
> >>>> +acpi_erst_realizefn_out(unsigned size) "total nvram size %u bytes"
> >>>> +acpi_erst_reset_in(unsigned record_count) "record_count %u"
> >>>> +acpi_erst_reset_out(unsigned record_count) "record_count %u"
> >>>> +acpi_erst_post_load(void *header, unsigned slot_size) "header: 0x%p
> >>>> slot_size %u"
> >>>> +acpi_erst_class_init_in(void)
> >>>> +acpi_erst_class_init_out(void)
> >>>> --
> >>>> 1.8.3.1
> >>>>
