Re: [PATCH 0/3] selftests/mm: add memory failure selftests

[Miaohe Lin <linmiaohe@huawei.com>]

On 2026/1/13 22:05, Philip Li wrote:
> On Mon, Jan 12, 2026 at 08:38:58PM +0100, David Hildenbrand (Red Hat) wrote:
>> On 1/12/26 13:44, Miaohe Lin wrote:
>>> On 2026/1/12 19:33, Miaohe Lin wrote:
> 
> ...
> 
>>>>>>> # # # Starting 6 tests from 2 test cases.
>>>>>>> # # #  RUN           memory_failure.madv_hard.anon ...
>>>>>>> # # #            OK  memory_failure.madv_hard.anon
>>>>>>> # not ok 71 memory-failure # exit=1
>>>>>>>
>>>>>>>
>>>>>>> Can the test maybe not deal with running in certain environments (config options etc)?
>>>>>>
>>>>>> To run the test, I think there should be:
>>>>>>     1.CONFIG_MEMORY_FAILURE and CONFIG_HWPOISON_INJECT should be enabled.
> 
> in 0day env, the configs are below
> 
> CONFIG_MEMORY_FAILURE=y
> CONFIG_HWPOISON_INJECT=m
> 
>>>>>>     2.Root privilege is required.
> 
> yes, use root to run
> 
>>>>>>     3.For dirty/clean pagecache testcases, the test file "./clean-page-cache-test-file" and
>>>>>>       "./dirty-page-cache-test-file" are assumed to be created on non-memory file systems
>>>>>>       such as xfs, ext4, etc.
> 
> this is a problem in 0day, the test is running in tmpfs. Let me further check
> to correct this.
> 
>>>>>>
>>>>>> Does your test environment break any of the above rules?
>>>>>
>>>>> It is 0day environment, so very likely yes. I suspect 1).
>>>
>>> Hi David,
>>>
>>> After taking a more close look, I think CONFIG_MEMORY_FAILURE and CONFIG_HWPOISON_INJECT should have been
>>> enabled in 0day environment or testcase memory_failure.madv_hard.anon should fail. memory_failure.madv_hard.anon
>>> will inject memory failure and expects seeing a SIGBUG signal.
>>
>> Good point.
>>
>>>
>>>>>
>>>>>> Am I expected to add some code to
>>>>>> guard against this?
>>>>>
>>>>> Yes, at least some.
>>>>>
>>>>> Checking for root privileges is not required. The tests are commonly run from non-memory file systems, but, in theory, could be run from nfs etc.
>>>>>
>>>>> If you require special file systems, take a look at gup_longterm.o where we test for some fileystsem types.
>>>
>>> And I think the cause of failures of testcases memory_failure.madv_hard.clean_pagecache and memory_failure.madv_hard.dirty_pagecache
>>> is they running on memory filesystems. The error pages are kept in page cache in that case while memory_failure.madv_hard.clean_pagecache
>>> expects to see the error page truncated.
>>
>> Maybe they are run on shmem? Good question. (@Phil?)
> 
> yes, it runs on tmpfs, let me further check to resolve it.

Thanks both. This information is really helpful. I will add some codes to handle this.

Thanks.
.