Re: [PATCH] test/cxl-mbox: Regression test for huge CXL_MEM_SEND_COMMAND out.size

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [Medium] User-space ndctl test patch mistakenly submitted to the Linux kernel tree.
- [Medium] Brittle error handling in test script module loading.
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commit d71b88195f1dc438adbcafc668b1cd91cd8a75fe
Author: Richard Cheng <icheng@nvidia.com>

test/cxl-mbox: Regression test for huge CXL_MEM_SEND_COMMAND out.size

This commit introduces a regression test for a CXL mailbox issue where a huge
out.size parameter could trigger a size > INT_MAX kvmalloc() WARN. The test
uses the cxl_test mock memdev and directly issues the CXL_MEM_SEND_COMMAND
ioctl.

Link: https://lore.kernel.org/all/20260624144147.53997-1-icheng@nvidia.com/

> diff --git a/test/cxl-mbox.c b/test/cxl-mbox.c
> new file mode 100644
> index 0000000000000..d81327ba17df4
> --- /dev/null
> +++ b/test/cxl-mbox.c
> @@ -0,0 +1,129 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// Copyright (C) 2026 Nvidia Corporation. All rights reserved.
> +#include <errno.h>
> +#include <fcntl.h>
> +#include <stdio.h>
> +#include <stdint.h>
> +#include <stddef.h>
> +#include <stdlib.h>
> +#include <syslog.h>
> +#include <string.h>
> +#include <unistd.h>
> +#include <sys/ioctl.h>
> +#include <cxl/libcxl.h>

[Severity: Medium]
Is this test actually intended for the ndctl repository rather than the Linux
kernel tree? It looks like it includes <cxl/libcxl.h>, which is an ndctl
user-space library header not present in the Linux kernel tree.

[ ... ]

> diff --git a/test/cxl-mbox.sh b/test/cxl-mbox.sh
> new file mode 100755
> index 0000000000000..67fecf5a3f46f
> --- /dev/null
> +++ b/test/cxl-mbox.sh
> @@ -0,0 +1,48 @@
> +#!/bin/bash -Ex
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (C) 2026 Nvidia Corporation. All rights reserved.
> +
> +. $(dirname "$0")/common

[Severity: Medium]
Does this source a 'common' test framework script from ndctl that does not
exist in the kernel tree?

> +
> +BIN="$TEST_PATH"/cxl-mbox
> +rc=77
> +# 237 is -ENODEV
> +ERR_NODEV=237
> +# TAINT_WARN is bit 9
> +TAINT_WARN=512
> +
> +trap 'err $LINENO' ERR
> +
> +modprobe -r cxl_test 2>/dev/null
> +modprobe cxl_test
> +# cxl_test alone does not autoload the mock memdev module on this box
> +modprobe cxl_mock_mem

[Severity: Medium]
Because this script runs with set -e (from the #!/bin/bash -Ex line), will
these unprotected modprobe commands immediately trigger the ERR trap and
abort the script if the modules are missing, instead of gracefully skipping
the test?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260624145843.55116-1-icheng@nvidia.com?part=1