[LTP] [PATCH] min_kver: Add kernel version requestions

[yangx.jy@fujitsu.com]

On 2021/3/30 16:18, zhaogongyi wrote:
> Hi Yang,
>
> I have seen the function definition in lapi/preadv2.h or lapi/pwritev2.h, but it seems not enough.
Hi Zhongyi,

It is enough to indicate that preadv2() and pwritev2() are supported on 
your enviroment.

> I run the testcases preadv201 and pwritev201 on my qemu, kernel version 4.4, arch is armeb, and report as follows:
>
> # ./preadv201
> tst_test.c:1294: TINFO: Timeout per run is 0h 05m 00s
> preadv201.c:91: TPASS: preadv2() read 64 bytes with content 'a' expectedly
> preadv201.c:91: TPASS: preadv2() read 64 bytes with content 'a' expectedly
> preadv201.c:91: TPASS: preadv2() read 32 bytes with content 'b' expectedly
> preadv201.c:64: TFAIL: preadv2() failed: EINVAL (22)
> preadv201.c:64: TFAIL: preadv2() failed: EINVAL (22)
> preadv201.c:64: TFAIL: preadv2() failed: EINVAL (22)
>
> Summary:
> passed   3
> failed   3
> broken   0
> skipped  0
> warnings 0
>
>
> # ./pwritev201
> tst_test.c:1294: TINFO: Timeout per run is 0h 05m 00s
> pwritev201.c:96: TPASS: pwritev2() wrote 64 bytes successfully with content 'a' expectedly
> pwritev201.c:96: TPASS: pwritev2() wrote 64 bytes successfully with content 'a' expectedly
> pwritev201.c:96: TPASS: pwritev2() wrote 64 bytes successfully with content 'a' expectedly
> pwritev201.c:62: TFAIL: pwritev2() failed: EINVAL (22)
> pwritev201.c:62: TFAIL: pwritev2() failed: EINVAL (22)
> pwritev201.c:62: TFAIL: pwritev2() failed: EINVAL (22)
>
> Summary:
> passed   3
> failed   3
> broken   0
> skipped  0
> warnings 0
>

It seems that preadv2() and pwritev2() cannot accept the offset argument 
which is set to -1.
You should find why preadv2() and pwritev2() cannot accept the offset == -1.
1) If LTP introduces the issue, you should send a patch to fix it(not 
add kernel version check).
2) If kernel introduces the issue, you should keep the test becasue it 
exposes the kernel bug as expected.
      Of course, you can also try to find which kernel commit fixes the 
issue if you want.

> See man 2, we known preadv2() and pwritev2() first appeared in Linux 4.6, so I think we need to check kernel version in testcases.

1) It is wrong to work around the issue about preadv2()/pwritev2() by 
kernel version check.
2) As Xu metioned on your patch(syscalls/shmctl04: Add kernel version 
requestions), kernel version check is not the best way to indicate if 
preadv2()/pwritev2() is supported.

Best Regards,
Xiao Yang
> Thanks!
>
> Best Regards,
> Gongyi
>
>
>> Hi Zhongyi,
>>
>> Do you get any issue here?
>>
>> It is unncessary to add version check because LTP has check the support of
>> preadv2/pwritev2:
>> 1) Call preadv2/pwritev2 directly if glibc provides it.
>> 2) Call syscall(__NR_preadv2/__NR_pwritev2) if glibc doesn't provides
>> preadv2/pwritev.
>> 3) Report TCONF if kernel doesn't support __NR_preadv2/__NR_pwritev2.
>>
>> Please reference "include/lapi/preadv2.h"
>>
>> Best Regards,
>> Xiao Yang
>> On 2021/3/30 15:44, Zhao Gongyi wrote:
>>> We need add kernel version requestions sinc preadv2() and pwritev2()
>>> first appeared in Linux 4.6.
>>>
>>> For those:
>>> 	testcases/kernel/syscalls/preadv2/preadv201.c
>>> 	testcases/kernel/syscalls/pwritev2/pwritev201.c
>>>
>>> Signed-off-by: Zhao Gongyi<zhaogongyi@huawei.com>
>>> ---
>>>    testcases/kernel/syscalls/preadv2/preadv201.c   | 1 +
>>>    testcases/kernel/syscalls/pwritev2/pwritev201.c | 1 +
>>>    2 files changed, 2 insertions(+)
>>>
>>> diff --git a/testcases/kernel/syscalls/preadv2/preadv201.c
>>> b/testcases/kernel/syscalls/preadv2/preadv201.c
>>> index 91e2b9889..e8220f94c 100644
>>> --- a/testcases/kernel/syscalls/preadv2/preadv201.c
>>> +++ b/testcases/kernel/syscalls/preadv2/preadv201.c
>>> @@ -111,6 +111,7 @@ static void cleanup(void)
>>>    }
>>>
>>>    static struct tst_test test = {
>>> +	.min_kver = "4.6",
>>>    	.tcnt = ARRAY_SIZE(tcases),
>>>    	.setup = setup,
>>>    	.cleanup = cleanup,
>>> diff --git a/testcases/kernel/syscalls/pwritev2/pwritev201.c
>>> b/testcases/kernel/syscalls/pwritev2/pwritev201.c
>>> index eba45b7d3..a8273e59d 100644
>>> --- a/testcases/kernel/syscalls/pwritev2/pwritev201.c
>>> +++ b/testcases/kernel/syscalls/pwritev2/pwritev201.c
>>> @@ -111,6 +111,7 @@ static void cleanup(void)
>>>    }
>>>
>>>    static struct tst_test test = {
>>> +	.min_kver = "4.6",
>>>    	.tcnt = ARRAY_SIZE(tcases),
>>>    	.setup = setup,
>>>    	.cleanup = cleanup,
>>> --
>>> 2.17.1
>>>
>>>
> .
>