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

[sashiko-bot@kernel.org]

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.

> +	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