Re: [ndctl PATCH v2] test/cxl-dax-hmem.sh: validate dax_hmem vs CXL collisions

[Dave Jiang <dave.jiang@intel.com>]

On 4/3/26 7:51 PM, Alison Schofield wrote:
> From: Dan Williams <dan.j.williams@intel.com>
> 
> Use the new "cxl_test.hmem_test" and "cxl_test.fail_autoassemble"
> module options to implement a new cxl-dax-hmem.sh test. The test
> checks dax_hmem takeover of Soft Reserve ranges that collide with
> autoassembled CXL regions. It depends on the cxl_mock_mem driver
> to launch multiple async probes before the dax_hmem driver attaches.
> 
> [as: do_skip on missing params, explicit param usage, robust unload,
> check_dmesg, misc style]
> 
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
> Tested-by: Alison Schofield <alison.schofield@intel.com>

Reviewed-by: Dave Jiang <dave.jiang@intel.com>

> ---
> 
> Changes in v2:
> - Add delay (cxl-list) between modprobe and dax lookup
>   In testing sometimes a daxctl right after modprobe fails to find
>   the devices.
> 
>  test/cxl-dax-hmem.sh | 68 ++++++++++++++++++++++++++++++++++++++++++++
>  test/meson.build     |  2 ++
>  2 files changed, 70 insertions(+)
>  create mode 100755 test/cxl-dax-hmem.sh
> 
> diff --git a/test/cxl-dax-hmem.sh b/test/cxl-dax-hmem.sh
> new file mode 100755
> index 000000000000..6f4ed5076870
> --- /dev/null
> +++ b/test/cxl-dax-hmem.sh
> @@ -0,0 +1,68 @@
> +#!/bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (C) 2026 Intel Corporation
> +
> +. $(dirname $0)/common
> +
> +rc=77
> +
> +set -ex
> +
> +trap 'err $LINENO' ERR
> +
> +check_prereq "jq"
> +
> +modinfo cxl_test | grep -q '^parm:.*hmem_test' || \
> +	do_skip "cxl_test hmem_test module param not available"
> +
> +modinfo cxl_test | grep -q '^parm:.*fail_autoassemble' || \
> +	do_skip "cxl_test fail_autoassemble module param not available"
> +
> +rc=1
> +
> +unload()
> +{
> +	modprobe -r dax_cxl 2>/dev/null || true
> +	modprobe -r dax_hmem 2>/dev/null || true
> +	modprobe -r cxl_mock_mem 2>/dev/null || true
> +	modprobe -r cxl_test 2>/dev/null || true
> +}
> +
> +find_dax_cxl()
> +{
> +	$DAXCTL list -R | jq -r \
> +		'.[] | select(.path | contains("cxl_acpi.0")) | .path'
> +}
> +
> +find_dax_hmem()
> +{
> +	$DAXCTL list -R | jq -r \
> +		'.[] | select(.path | contains("hmem_platform.1")) | .path'
> +}
> +
> +unload
> +
> +# Verify CXL autoassembly claims the Soft Reserve range before dax_hmem
> +modprobe cxl_mock_mem
> +modprobe cxl_test hmem_test=1
> +$CXL list
> +
> +dax=$(find_dax_cxl)
> +[[ -z "$dax" ]] && err $LINENO
> +dax=$(find_dax_hmem)
> +[[ -n "$dax" ]] && err $LINENO
> +
> +unload
> +
> +# Verify dax_hmem claims the Soft Reserve range when CXL autoassembly fails
> +modprobe cxl_mock_mem
> +modprobe cxl_test hmem_test=1 fail_autoassemble=1
> +$CXL list
> +
> +dax=$(find_dax_cxl)
> +[[ -n "$dax" ]] && err $LINENO
> +dax=$(find_dax_hmem)
> +[[ -z "$dax" ]] && err $LINENO
> +
> +unload
> +check_dmesg "$LINENO"
> diff --git a/test/meson.build b/test/meson.build
> index 593edf552b36..4260a3fa4448 100644
> --- a/test/meson.build
> +++ b/test/meson.build
> @@ -169,6 +169,7 @@ cxl_destroy_region = find_program('cxl-destroy-region.sh')
>  cxl_qos_class = find_program('cxl-qos-class.sh')
>  cxl_translate = find_program('cxl-translate.sh')
>  cxl_elc = find_program('cxl-elc.sh')
> +cxl_dax_hmem = find_program('cxl-dax-hmem.sh')
>  
>  tests = [
>    [ 'libndctl',               libndctl,		  'ndctl' ],
> @@ -203,6 +204,7 @@ tests = [
>    [ 'cxl-qos-class.sh',       cxl_qos_class,      'cxl'   ],
>    [ 'cxl-translate.sh',       cxl_translate,      'cxl'   ],
>    [ 'cxl-elc.sh',             cxl_elc,            'cxl'   ],
> +  [ 'cxl-dax-hmem.sh',        cxl_dax_hmem,       'cxl'   ],
>  ]
>  
>  if get_option('destructive').enabled()