On Mon, Oct 10, 2022 at 10:34 PM Tony Luck <tony.luck@xxxxxxxxx> wrote:
>
> If there is no user space consumer of extlog_mem trace records, then
> Linux properly handles multiple error records in an ELOG block
>
> extlog_print()
> print_extlog_rcd()
> __print_extlog_rcd()
> cper_estatus_print()
> apei_estatus_for_each_section()
>
> But the other code path hard codes looking for a single record to
> output a trace record.
>
> Fix by using the same apei_estatus_for_each_section() iterator
> to step over all records.
>
> Fixes: 2dfb7d51a61d ("trace, RAS: Add eMCA trace event interface")
> Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx>
> ---
>
> Changes since v1: Oops. Cut & pasted the apei_estatus_for_each_section()
> line, but forgot to change the argument from "estatus" to "tmp". Need to
> walk the *copy* that was made, not the original because BIOS is allowed to
> stomp on it as soon as it sees block_status has been cleared.
>
> drivers/acpi/acpi_extlog.c | 33 ++++++++++++++++++++-------------
> 1 file changed, 20 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/acpi/acpi_extlog.c b/drivers/acpi/acpi_extlog.c
> index 72f1fb77abcd..e648158368a7 100644
> --- a/drivers/acpi/acpi_extlog.c
> +++ b/drivers/acpi/acpi_extlog.c
> @@ -12,6 +12,7 @@
> #include <linux/ratelimit.h>
> #include <linux/edac.h>
> #include <linux/ras.h>
> +#include <acpi/ghes.h>
> #include <asm/cpu.h>
> #include <asm/mce.h>
>
> @@ -138,8 +139,8 @@ static int extlog_print(struct notifier_block *nb, unsigned long val,
> int cpu = mce->extcpu;
> struct acpi_hest_generic_status *estatus, *tmp;
> struct acpi_hest_generic_data *gdata;
> - const guid_t *fru_id = &guid_null;
> - char *fru_text = "";
> + const guid_t *fru_id;
> + char *fru_text;
> guid_t *sec_type;
> static u32 err_seq;
>
> @@ -160,17 +161,23 @@ static int extlog_print(struct notifier_block *nb, unsigned long val,
>
> /* log event via trace */
> err_seq++;
> - gdata = (struct acpi_hest_generic_data *)(tmp + 1);
> - if (gdata->validation_bits & CPER_SEC_VALID_FRU_ID)
> - fru_id = (guid_t *)gdata->fru_id;
> - if (gdata->validation_bits & CPER_SEC_VALID_FRU_TEXT)
> - fru_text = gdata->fru_text;
> - sec_type = (guid_t *)gdata->section_type;
> - if (guid_equal(sec_type, &CPER_SEC_PLATFORM_MEM)) {
> - struct cper_sec_mem_err *mem = (void *)(gdata + 1);
> - if (gdata->error_data_length >= sizeof(*mem))
> - trace_extlog_mem_event(mem, err_seq, fru_id, fru_text,
> - (u8)gdata->error_severity);
> + apei_estatus_for_each_section(tmp, gdata) {
> + if (gdata->validation_bits & CPER_SEC_VALID_FRU_ID)
> + fru_id = (guid_t *)gdata->fru_id;
> + else
> + fru_id = &guid_null;
> + if (gdata->validation_bits & CPER_SEC_VALID_FRU_TEXT)
> + fru_text = gdata->fru_text;
> + else
> + fru_text = "";
> + sec_type = (guid_t *)gdata->section_type;
> + if (guid_equal(sec_type, &CPER_SEC_PLATFORM_MEM)) {
> + struct cper_sec_mem_err *mem = (void *)(gdata + 1);
> +
> + if (gdata->error_data_length >= sizeof(*mem))
> + trace_extlog_mem_event(mem, err_seq, fru_id, fru_text,
> + (u8)gdata->error_severity);
> + }
> }
>
> out:
> --
Applied as 6.1-rc material, thanks!
