Re: [PATCH v2 08/13] acpi/ghes: Cleanup the code which gets ghes ged state

[Igor Mammedov <imammedo@redhat.com>]

On Wed, 29 Jan 2025 09:04:14 +0100
Mauro Carvalho Chehab <mchehab+huawei@kernel.org> wrote:

> Move the check logic into a common function and simplify the
> code which checks if GHES is enabled and was properly setup.
> 
> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

with nits fixed:
Reviewed-by:  Igor Mammedov <imammedo@redhat.com>

> ---
>  hw/acpi/ghes-stub.c    |  7 ++++---
>  hw/acpi/ghes.c         | 43 ++++++++++++------------------------------
>  include/hw/acpi/ghes.h | 15 ++++++++-------
>  target/arm/kvm.c       |  8 ++++++--
>  4 files changed, 30 insertions(+), 43 deletions(-)
> 
> diff --git a/hw/acpi/ghes-stub.c b/hw/acpi/ghes-stub.c
> index 7cec1812dad9..40f660c246fe 100644
> --- a/hw/acpi/ghes-stub.c
> +++ b/hw/acpi/ghes-stub.c
> @@ -11,12 +11,13 @@
>  #include "qemu/osdep.h"
>  #include "hw/acpi/ghes.h"
>  
> -int acpi_ghes_memory_errors(uint16_t source_id, uint64_t physical_address)
> +int acpi_ghes_memory_errors(AcpiGhesState *ags, uint16_t source_id,
> +                            uint64_t physical_address)
>  {
>      return -1;
>  }
>  
> -bool acpi_ghes_present(void)
> +AcpiGhesState *acpi_ghes_get_state(void)
>  {
> -    return false;
> +    return NULL;
>  }
> diff --git a/hw/acpi/ghes.c b/hw/acpi/ghes.c
> index 38ff95273706..849abfa12187 100644
> --- a/hw/acpi/ghes.c
> +++ b/hw/acpi/ghes.c
> @@ -407,18 +407,12 @@ void acpi_ghes_add_fw_cfg(AcpiGhesState *ags, FWCfgState *s,
>          fw_cfg_add_file_callback(s, ACPI_HEST_ADDR_FW_CFG_FILE, NULL, NULL,
>              NULL, &(ags->hest_addr_le), sizeof(ags->hest_addr_le), false);
>      }
> -
> -    ags->present = true;
>  }
>  
>  static void get_hw_error_offsets(uint64_t ghes_addr,
>                                   uint64_t *cper_addr,
>                                   uint64_t *read_ack_register_addr)
>  {
> -    if (!ghes_addr) {
> -        return;
> -    }
> -
>      /*
>       * non-HEST version supports only one source, so no need to change
>       * the start offset based on the source ID. Also, we can't validate
> @@ -447,9 +441,6 @@ static void get_ghes_source_offsets(uint16_t source_id,
>      uint64_t err_source_entry, error_block_addr;
>      uint32_t num_sources, i;
>  
> -    if (!hest_entry_addr) {
> -        return;
> -    }
>  
>      cpu_physical_memory_read(hest_entry_addr, &num_sources,
>                               sizeof(num_sources));
> @@ -515,27 +506,17 @@ static void get_ghes_source_offsets(uint16_t source_id,
>  NotifierList acpi_generic_error_notifiers =
>      NOTIFIER_LIST_INITIALIZER(error_device_notifiers);
>  
> -void ghes_record_cper_errors(const void *cper, size_t len,
> +void ghes_record_cper_errors(AcpiGhesState *ags, const void *cper, size_t len,
>                               uint16_t source_id, Error **errp)
>  {
>      uint64_t cper_addr = 0, read_ack_register_addr = 0, read_ack_register;
> -    AcpiGedState *acpi_ged_state;
> -    AcpiGhesState *ags;
>  
>      if (len > ACPI_GHES_MAX_RAW_DATA_LENGTH) {
>          error_setg(errp, "GHES CPER record is too big: %zd", len);
>          return;
>      }
>  
> -    acpi_ged_state = ACPI_GED(object_resolve_path_type("", TYPE_ACPI_GED,
> -                                                       NULL));
> -    if (!acpi_ged_state) {
> -        error_setg(errp, "Can't find ACPI_GED object");
> -        return;
> -    }
> -    ags = &acpi_ged_state->ghes_state;
> -
> -    if (!ags->hest_addr_le) {
> +    if (!ags->use_hest_addr) {
>          get_hw_error_offsets(le64_to_cpu(ags->hw_error_le),
>                               &cper_addr, &read_ack_register_addr);
>      } else {
> @@ -543,11 +524,6 @@ void ghes_record_cper_errors(const void *cper, size_t len,
>                                  &cper_addr, &read_ack_register_addr, errp);
>      }
>  
> -    if (!cper_addr) {
> -        error_setg(errp, "can not find Generic Error Status Block");
> -        return;
> -    }
> -
>      cpu_physical_memory_read(read_ack_register_addr,
>                               &read_ack_register, sizeof(read_ack_register));
>  
> @@ -573,7 +549,8 @@ void ghes_record_cper_errors(const void *cper, size_t len,
>      notifier_list_notify(&acpi_generic_error_notifiers, NULL);
>  }
>  
> -int acpi_ghes_memory_errors(uint16_t source_id, uint64_t physical_address)
> +int acpi_ghes_memory_errors(AcpiGhesState *ags, uint16_t source_id,
> +                            uint64_t physical_address)
>  {
>      /* Memory Error Section Type */
>      const uint8_t guid[] =
> @@ -599,7 +576,7 @@ int acpi_ghes_memory_errors(uint16_t source_id, uint64_t physical_address)
>      acpi_ghes_build_append_mem_cper(block, physical_address);
>  
>      /* Report the error */
> -    ghes_record_cper_errors(block->data, block->len, source_id, &errp);
> +    ghes_record_cper_errors(ags, block->data, block->len, source_id, &errp);
>  
>      g_array_free(block, true);
>  
> @@ -611,7 +588,7 @@ int acpi_ghes_memory_errors(uint16_t source_id, uint64_t physical_address)
>      return 0;
>  }
>  
> -bool acpi_ghes_present(void)
> +AcpiGhesState *acpi_ghes_get_state(void)
>  {
>      AcpiGedState *acpi_ged_state;
>      AcpiGhesState *ags;
> @@ -620,8 +597,12 @@ bool acpi_ghes_present(void)
>                                                         NULL));
>  
>      if (!acpi_ged_state) {
> -        return false;
> +        return NULL;
>      }
>      ags = &acpi_ged_state->ghes_state;
> -    return ags->present;
> +
> +    if (!ags->hw_error_le && !ags->hest_addr_le) {

should we add a warning here?
(consider case where firmware hasn't managed to update pointers for some reason)

> +        return NULL;
> +    }
> +    return ags;
>  }
> diff --git a/include/hw/acpi/ghes.h b/include/hw/acpi/ghes.h
> index 80a0c3fcfaca..e1b66141d01c 100644
> --- a/include/hw/acpi/ghes.h
> +++ b/include/hw/acpi/ghes.h
> @@ -63,7 +63,6 @@ enum AcpiGhesNotifyType {
>  typedef struct AcpiGhesState {
>      uint64_t hest_addr_le;
>      uint64_t hw_error_le;
> -    bool present; /* True if GHES is present at all on this board */
>      bool use_hest_addr; /* True if HEST address is present */
>  } AcpiGhesState;
>  
> @@ -87,15 +86,17 @@ void acpi_build_hest(AcpiGhesState *ags, GArray *table_data,
>                       const char *oem_id, const char *oem_table_id);
>  void acpi_ghes_add_fw_cfg(AcpiGhesState *vms, FWCfgState *s,
>                            GArray *hardware_errors);
> -int acpi_ghes_memory_errors(uint16_t source_id, uint64_t error_physical_addr);
> -void ghes_record_cper_errors(const void *cper, size_t len,
> +int acpi_ghes_memory_errors(AcpiGhesState *ags, uint16_t source_id,
> +                            uint64_t error_physical_addr);
> +void ghes_record_cper_errors(AcpiGhesState *ags, const void *cper, size_t len,
>                               uint16_t source_id, Error **errp);
>  
>  /**
> - * acpi_ghes_present: Report whether ACPI GHES table is present
> + * acpi_ghes_get_state: Get a pointer for ACPI ghes state
>   *
> - * Returns: true if the system has an ACPI GHES table and it is
> - * safe to call acpi_ghes_memory_errors() to record a memory error.
> + * Returns: a pointer to ghes state if the system has an ACPI GHES table,
> + * it is enabled and it is safe to call acpi_ghes_memory_errors() to record
> + * a memory error. Returns false, otherwise.
>   */
> -bool acpi_ghes_present(void);
> +AcpiGhesState *acpi_ghes_get_state(void);
>  #endif
> diff --git a/target/arm/kvm.c b/target/arm/kvm.c
> index da30bdbb2349..544ff174784d 100644
> --- a/target/arm/kvm.c
> +++ b/target/arm/kvm.c
> @@ -2366,10 +2366,13 @@ void kvm_arch_on_sigbus_vcpu(CPUState *c, int code, void *addr)
>  {
>      ram_addr_t ram_addr;
>      hwaddr paddr;
> +    AcpiGhesState *ags;
>  
>      assert(code == BUS_MCEERR_AR || code == BUS_MCEERR_AO);
>  
> -    if (acpi_ghes_present() && addr) {
> +    ags = acpi_ghes_get_state();

> +
I'd drop this newline

> +    if (ags && addr) {
>          ram_addr = qemu_ram_addr_from_host(addr);
>          if (ram_addr != RAM_ADDR_INVALID &&
>              kvm_physical_memory_addr_from_host(c->kvm_state, addr, &paddr)) {
> @@ -2387,7 +2390,8 @@ void kvm_arch_on_sigbus_vcpu(CPUState *c, int code, void *addr)
>               */
>              if (code == BUS_MCEERR_AR) {
>                  kvm_cpu_synchronize_state(c);
> -                if (!acpi_ghes_memory_errors(ACPI_HEST_SRC_ID_SEA, paddr)) {
> +                if (!acpi_ghes_memory_errors(ags, ACPI_HEST_SRC_ID_SEA,
> +                                             paddr)) {
>                      kvm_inject_arm_sea(c);
>                  } else {
>                      error_report("failed to record the error");