Re: [PATCH V2 1/6] tools/perf: Move powerpc VPA-DTL auxtrace init into a separate file

[Athira Rajeev <atrajeev@linux.ibm.com>]

> On 20 Jul 2026, at 4:45 PM, sashiko-bot@kernel.org wrote:
> 
> Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
> - [Medium] The newly added file `vpa-dtl.c` uses `zalloc()` but fails to include `<linux/zalloc.h>`. On 64-bit platforms like PowerPC, this implicit declaration causes the compiler to assume `zalloc` returns `int`, leading to the truncation of the upper 32 bits of the returned 64-bit pointer.
> --
> 
> --- Patch [1]: [PATCH V2 1/6] tools/perf: Move powerpc VPA-DTL auxtrace init into a separate file ---
> commit 36d571f8cc56fc84bd8c942791167ff968206898
> Author: Athira Rajeev <atrajeev@linux.ibm.com>
> 
> tools/perf: Move powerpc VPA-DTL auxtrace init into a separate file
> 
> This commit extracts the VPA-DTL auxtrace recording initializer into a new
> file, vpa-dtl.c. It reduces auxtrace.c to a thin dispatch layer to prepare
> for HTM recording.
> 
>> diff --git a/tools/perf/arch/powerpc/util/vpa-dtl.c b/tools/perf/arch/powerpc/util/vpa-dtl.c
>> new file mode 100644
>> index 0000000000000..fde388d874775
>> --- /dev/null
>> +++ b/tools/perf/arch/powerpc/util/vpa-dtl.c
>> @@ -0,0 +1,95 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * VPA DTL AUX tracing support
>> + */
>> +
>> +#include <linux/kernel.h>
>> +#include <linux/types.h>
>> +#include <linux/string.h>
>> +#include <errno.h>
>> +#include <stdlib.h>
>> +#include <limits.h>
>> +#include "../../util/cpumap.h"
>> +#include "../../util/evsel.h"
>> +#include "../../util/evlist.h"
>> +#include "../../util/session.h"
>> +#include "../../util/util.h"
>> +#include "../../util/debug.h"
>> +#include "../../util/auxtrace.h"
>> +#include "../../util/powerpc-vpadtl.h"
>> +#include "../../util/record.h"
>> +#include <internal/lib.h> // page_size
> 
> [ ... ]
> 
>> +struct auxtrace_record *vpa_dtl_recording_init(struct evsel *pos, int *err)
>> +{
>> + struct auxtrace_record *aux;
>> +
>> + /*
>> + * To obtain the auxtrace buffer file descriptor, the auxtrace event
>> + * must come first.
>> + */
>> + evlist__to_front(pos->evlist, pos);
>> +
>> + aux = zalloc(sizeof(*aux));
> 
> [Severity: Medium]
> Is the <linux/zalloc.h> include missing from the headers at the top of the
> file?
> 
> Since zalloc is used here without a declaration, the compiler will treat it
> as implicitly declared and returning an int. On 64-bit platforms like PowerPC,
> this truncates the upper 32 bits of the returned pointer, which could result
> in a segmentation fault at runtime.
> 

Sure, will be fixed in V3

Thanks
Athira

>> + if (aux == NULL) {
>> + pr_debug("aux record allocation failed (-ENOMEM)\n");
>> + *err = -ENOMEM;
>> + return NULL;
>> + }
> 
> -- 
> Sashiko AI review · https://sashiko.dev/#/patchset/20260720105218.14277-1-atrajeev@linux.ibm.com?part=1