Re: [PATCH v4 08/12] drm/xe/cper: Emit cper record to trace buf

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] trace: xe_error_cper uses %pU instead of %pUl for guid_t formatting
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commit 2df74abeb761bb9cbc4580031c2be3af5f19e10b
Author: Badal Nilawar <badal.nilawar@intel.com>

drm/xe/cper: Emit cper record to trace buf
    
This commit introduces the xe_error_cper tracepoint to emit assembled CPER
records to the trace buffer. The events carry the device name, platform ID,
FRU ID, severity, and the Intel error section header so tools can pick them up.

> diff --git a/drivers/gpu/drm/xe/xe_trace_cper.h b/drivers/gpu/drm/xe/xe_trace_cper.h
> new file mode 100644
> --- /dev/null
> +++ b/drivers/gpu/drm/xe/xe_trace_cper.h
[ ... ]
> +TRACE_EVENT(xe_error_cper,
> +	TP_PROTO(struct xe_device *xe,
> +	    const guid_t *platform_id, const guid_t *fru_id,
[ ... ]
> +	TP_fast_assign(
> +	    __assign_str(dev);
> +	    __entry->sev = severity;
> +	    memcpy(__entry->platform_id, platform_id, UUID_SIZE);
> +	    memcpy(__entry->fru_id, fru_id, UUID_SIZE);
> +	    memcpy(__entry->ihdr_raw, ihdr, sizeof(struct xe_cper_sec_intel_err_hdr));
> +	    __entry->cper_len = cper_len;
> +	    memcpy(__get_dynamic_array(cper), cper, cper_len);
> +	    ),
> +
> +	TP_printk("dev=%s severity=%d platform_id=%pU fru_id=%pU "
> +		"intel_err_hdr_raw=%s cper_len=%u cper_raw=%s",

[Severity: Low]
Since platform_id and fru_id are guid_t types (which are little-endian per
UEFI/CPER specifications), shouldn't this use the %pUl format specifier
instead of %pU?

The Linux kernel's %pU specifier assumes a big-endian uuid_t layout. Using
it here will cause the first three groups of the UUID to be byte-swapped in
the trace output, which might break correlation with platform specifications
and CPER tooling.

> +		__get_str(dev), __entry->sev,
> +		__entry->platform_id, __entry->fru_id,
> +		__print_hex(__entry->ihdr_raw,
> +		    sizeof(struct xe_cper_sec_intel_err_hdr)),
> +		__entry->cper_len,
> +		__print_hex(__get_dynamic_array(cper),
> +		    __entry->cper_len))
> +);

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261009104602.1075405-14-badal.nilawar@intel.com?part=8