Re: ndctl cxl test suite fails in arm64 QEMU

[Itaru Kitayama <itaru.kitayama@linux.dev>]

Hi,

> On Feb 27, 2025, at 4:30, Dave Jiang <dave.jiang@intel.com> wrote:
> 
> 
> 
> On 2/25/25 3:37 PM, Itaru Kitayama wrote:
>> Hi Marc,
>> 
>>> On Feb 26, 2025, at 2:08, Marc Herbert <Marc.Herbert@linux.intel.com> wrote:
>>> 
>>> On 2025-02-24 20:09, Itaru Kitayama wrote:
>>>> 
>>>> Has anyone noticed the ndctl cxl test suite failures I reported below on arm64, QEMU emulation?
>>>> 
>>>> https://github.com/pmem/ndctl/issues/278
>>>> 
>>>> I’m using Jonathan’s latest CXL capable QEMU [1], and the latest CXL kernel [2].
>>>> 
>>> 
>>> 
>>> Hi,
>>> 
>>> Sorry I wanted to spend more time and share a more detailed answer and
>>> of course I got side-tracked.
>>> 
>>> Do you have CONFIG_RANDOMIZE_MEMORY on?
>>> 
>>> If yes then please try this either this:
>>> 
>>> cd kernel
>>> ./scripts/config -d CONFIG_RANDOMIZE_MEMORY
>>> 
>>> ... or this:
>>> 
>>> --- a/run_qemu.sh
>>> +++ b/run_qemu.sh
>>> @@ -681,6 +681,7 @@ build_kernel_cmdline()
>>> "initcall_debug"
>>> "log_buf_len=20M"
>>> "memory_hotplug.memmap_on_memory=force"
>>> + "nokaslr"
>>> )
>>> if [[ $_arg_gdb == "on" ]]; then
>>> kcmd+=(
>> 
>> I chose the kernel configuration change and rebuilt the kernel, modules installed, then finally cxl_test kernel module installed on the emulated system, but I got worth results (occasionally, the kernel OOPS as well):
> 
> There's a known lockdep false positive that can trigger and cause cxl_test to fail. Does the kernel OOPS go away once you disable lockdep?

Instead of disabling lockdep, pulling cxl next this morning, so far made the spurious error go away.

Itaru.

> 
> DJ
> 
>> 
>> Log of Meson test suite run on 2025-02-26T07:32:24.101461
>> 
>> Inherited environment: LANG=C.UTF-8 LS_COLORS='' TERM=xterm-256color PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/snap/bin MAIL=/var/mail/root LOGNAME=root USER=root HOME=/root SHELL=/bin/bash SUDO_COMMAND='/usr/bin/meson test cxl-region-sysfs.sh' SUDO_USER=realm SUDO_UID=1000 SUDO_GID=1000 
>> 
>> ==================================== 1/1 =====================================
>> test:         ndctl:cxl / cxl-region-sysfs.sh
>> start time:   22:32:24
>> duration:     0.71s
>> result:       exit status 1
>> command:      NDCTL=/home/realm/projects/ndctl/build/ndctl/ndctl DAXCTL=/home/realm/projects/ndctl/build/daxctl/daxctl TEST_PATH=/home/realm/projects/ndctl/build/test UBSAN_OPTIONS=halt_on_error=1:abort_on_error=1:print_summary=1:print_stacktrace=1 ASAN_OPTIONS=halt_on_error=1:abort_on_error=1:print_summary=1 MALLOC_PERTURB_=29 MSAN_OPTIONS=halt_on_error=1:abort_on_error=1:print_summary=1:print_stacktrace=1 DATA_PATH=/home/realm/projects/ndctl/test MESON_TEST_ITERATION=1 LD_LIBRARY_PATH=/home/realm/projects/ndctl/build/daxctl/lib:/home/realm/projects/ndctl/build/ndctl/lib:/home/realm/projects/ndctl/build/cxl/lib /bin/bash /home/realm/projects/ndctl/test/cxl-region-sysfs.sh
>> ----------------------------------- stdout -----------------------------------
>> test/cxl-region-sysfs.sh: failed at line 40
>> ----------------------------------- stderr -----------------------------------
>> + trap 'err $LINENO' ERR
>> + check_prereq jq
>> + command -v jq
>> + modprobe -r cxl_test
>> + modprobe cxl_test
>> + rc=1
>> ++ ./cxl/cxl list -b cxl_test -D -d root
>> ++ jq -r '.[] |
>>  select(.pmem_capable == true) |
>>  select(.nr_targets == 2) |
>>  .decoder'
>>  Warning: no matching devices found
>> 
>> + decoder=
>> + readarray -t mem
>> ++ ./cxl/cxl list -M -d
>> ++ jq -r '.[].memdev'
>>  Error: switch `d' requires a value
>> 
>> usage: cxl list [<options>]
>> 
>>    -d, --decoder <decoder device name>
>>                          filter by CXL decoder device name(s) / class
>> + readarray -t endpoint
>> ++ ./cxl/cxl reserve-dpa -t pmem -s 268435456
>> ++ jq -r '.[] | .decoder.decoder'
>> 
>> usage: cxl reserve-dpa <mem0> [<mem1>..<memn>] [<options>]
>> 
>>    -b, --bus <bus name>  Limit operation to the specified bus
>>    -v, --verbose         turn on debug
>>    -S, --serial          use serial numbers to id memdevs
>>    -s, --size <size>     size in bytes (Default: all available capacity)
>>    -d, --decoder <decoder instance id>
>>                          override the automatic decoder selection
>>    -t, --type <type>     'pmem' or 'ram' (volatile) (Default: 'pmem')
>>    -f, --force           Attempt 'expected to fail' operations
>> 
>> ++ cat /sys/bus/cxl/devices//create_pmem_region
>> cat: /sys/bus/cxl/devices//create_pmem_region: No such file or directory
>> + region=
>> ++ err 40
>> +++ basename /home/realm/projects/ndctl/test/cxl-region-sysfs.sh
>> ++ echo test/cxl-region-sysfs.sh: failed at line 40
>> ++ '[' -n '' ']'
>> ++ exit 1
>> ==============================================================================
>> 
>> 
>> Summary of Failures:
>> 
>> 1/1 ndctl:cxl / cxl-region-sysfs.sh FAIL             0.71s   exit status 1
>> 
>> Ok:                 0   
>> Expected Fail:      0   
>> Fail:               1   
>> Unexpected Pass:    0   
>> Skipped:            0   
>> Timeout:            0