Re: [PATCH v4 03/14] acpi/ghes: Use HEST table offsets when preparing GHES records

Igor Mammedov
2025-02-26T15:16:26Z

On Fri, 21 Feb 2025 15:35:12 +0100
Mauro Carvalho Chehab <mchehab+huawei@kernel.org> wrote:

> There are two pointers that are needed during error injection:
>
> 1. The start address of the CPER block to be stored;
> 2. The address of the ack.
s/ack/read_ack/

>
> It is preferable to calculate them from the HEST table. This allows
> checking the source ID, the size of the table and the type of the
> HEST error block structures.
>
> Yet, keep the old code, as this is needed for migration purposes

+ from older QEMU versions

>
> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> ---
> hw/acpi/ghes.c | 100 +++++++++++++++++++++++++++++++++++++++++
> include/hw/acpi/ghes.h | 2 +-
> 2 files changed, 101 insertions(+), 1 deletion(-)
>
> diff --git a/hw/acpi/ghes.c b/hw/acpi/ghes.c
> index ba37be9e7022..7efea519f766 100644
> --- a/hw/acpi/ghes.c
> +++ b/hw/acpi/ghes.c
> @@ -41,6 +41,12 @@
> /* Address offset in Generic Address Structure(GAS) */
> #define GAS_ADDR_OFFSET 4
>
> +/*
> + * ACPI spec 1.0b
> + * 5.2.3 System Description Table Header
> + */
> +#define ACPI_DESC_HEADER_OFFSET 36
> +
> /*
> * The total size of Generic Error Data Entry
> * ACPI 6.1/6.2: 18.3.2.7.1 Generic Error Data,
> @@ -61,6 +67,30 @@
> */
> #define ACPI_GHES_GESB_SIZE 20
>
> +/*
> + * See the memory layout map at docs/specs/acpi_hest_ghes.rst.
> + */
> +
> +/*
> + * ACPI 6.1: 18.3.2.8 Generic Hardware Error Source version 2
> + * Table 18-344 Generic Hardware Error Source version 2 (GHESv2) Structure
> + */
> +#define HEST_GHES_V2_ENTRY_SIZE 92
> +
> +/*
> + * ACPI 6.1: 18.3.2.7: Generic Hardware Error Source
wrong chapter, read ack can't be in v1 GHES

> + * Table 18-344 Generic Hardware Error Source version 2 (GHESv2) Structure
> + * Read Ack Register
> + */
> +#define GHES_READ_ACK_ADDR_OFF 64
> +
> +/*
> + * ACPI 6.1: 18.3.2.7: Generic Hardware Error Source
> + * Table 18-341 Generic Hardware Error Source Structure
> + * Error Status Address
> + */
> +#define GHES_ERR_STATUS_ADDR_OFF 20
> +
> /*
> * Values for error_severity field
> */
> @@ -412,6 +442,73 @@ static void get_hw_error_offsets(uint64_t ghes_addr,
> *read_ack_register_addr = ghes_addr + sizeof(uint64_t);
> }
>
> +static void get_ghes_source_offsets(uint16_t source_id,
> + uint64_t hest_addr,
> + uint64_t *cper_addr,
> + uint64_t *read_ack_start_addr,
> + Error **errp)
> +{
> + uint64_t hest_err_block_addr, hest_read_ack_addr;
> + uint64_t err_source_entry, error_block_addr;
> + uint32_t num_sources, i;
> +
> + hest_addr += ACPI_DESC_HEADER_OFFSET;
> +
> + cpu_physical_memory_read(hest_addr, &num_sources,
> + sizeof(num_sources));
> + num_sources = le32_to_cpu(num_sources);
> +
> + err_source_entry = hest_addr + sizeof(num_sources);
> +
> + /*
> + * Currently, HEST Error source navigates only for GHESv2 tables
> + */
> + for (i = 0; i < num_sources; i++) {
> + uint64_t addr = err_source_entry;
> + uint16_t type, src_id;
> +
> + cpu_physical_memory_read(addr, &type, sizeof(type));
> + type = le16_to_cpu(type);
> +
> + /* For now, we only know the size of GHESv2 table */
> + if (type != ACPI_GHES_SOURCE_GENERIC_ERROR_V2) {
> + error_setg(errp, "HEST: type %d not supported.", type);
> + return;
> + }
> +
> + /* Compare CPER source address at the GHESv2 structure */
^^^^^ typo?

> + addr += sizeof(type);
> + cpu_physical_memory_read(addr, &src_id, sizeof(src_id));
> + if (le16_to_cpu(src_id) == source_id) {
> + break;
> + }
> +
> + err_source_entry += HEST_GHES_V2_ENTRY_SIZE;
> + }
> + if (i == num_sources) {
> + error_setg(errp, "HEST: Source %d not found.", source_id);
> + return;
> + }
> +
> + /* Navigate though table address pointers */
^^^^^ typo

> + hest_err_block_addr = err_source_entry + GHES_ERR_STATUS_ADDR_OFF +
> + GAS_ADDR_OFFSET;
> +
> + cpu_physical_memory_read(hest_err_block_addr, &error_block_addr,
> + sizeof(error_block_addr));
> + error_block_addr = le64_to_cpu(error_block_addr);
> +
> + cpu_physical_memory_read(error_block_addr, cper_addr,
> + sizeof(*cper_addr));
> + *cper_addr = le64_to_cpu(*cper_addr);
> +
> + hest_read_ack_addr = err_source_entry + GHES_READ_ACK_ADDR_OFF +
> + GAS_ADDR_OFFSET;
> + cpu_physical_memory_read(hest_read_ack_addr, read_ack_start_addr,
> + sizeof(*read_ack_start_addr));
> + *read_ack_start_addr = le64_to_cpu(*read_ack_start_addr);
> +}
> +
> void ghes_record_cper_errors(const void *cper, size_t len,
> uint16_t source_id, Error **errp)
> {
> @@ -437,6 +534,9 @@ void ghes_record_cper_errors(const void *cper, size_t len,
> if (!ags->use_hest_addr) {
> get_hw_error_offsets(le64_to_cpu(ags->hw_error_le),
> &cper_addr, &read_ack_register_addr);
> + } else {
> + get_ghes_source_offsets(source_id, le64_to_cpu(ags->hest_addr_le),
> + &cper_addr, &read_ack_register_addr, errp);
> }
>
> if (!cper_addr) {
> diff --git a/include/hw/acpi/ghes.h b/include/hw/acpi/ghes.h
> index 454e97b5341c..2f06e433ce04 100644
> --- a/include/hw/acpi/ghes.h
> +++ b/include/hw/acpi/ghes.h
> @@ -80,7 +80,7 @@ enum {
> typedef struct AcpiGhesState {
> uint64_t hest_addr_le;
> uint64_t hw_error_le;
> - bool use_hest_addr; /* Currently, always false */
> + bool use_hest_addr; /* True if HEST address is present */
> } AcpiGhesState;
>
> void acpi_build_hest(AcpiGhesState *ags, GArray *table_data,