Re: [kvm-unit-tests PATCH 5/9] s390x: topology: Refine stsi header test

[Janosch Frank <frankja@linux.ibm.com>]

On 10/11/23 13:19, Nina Schoetterl-Glausch wrote:
> On Wed, 2023-10-11 at 13:16 +0200, Janosch Frank wrote:
>> On 10/11/23 10:56, Nina Schoetterl-Glausch wrote:
>>> Add checks for length field.
>>> Also minor refactor.
>>>
>>> Signed-off-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
>>> ---
>>>    s390x/topology.c | 15 +++++++++------
>>>    1 file changed, 9 insertions(+), 6 deletions(-)
>>>
>>> diff --git a/s390x/topology.c b/s390x/topology.c
>>> index 5374582f..0ba57986 100644
>>> --- a/s390x/topology.c
>>> +++ b/s390x/topology.c
>>> @@ -187,18 +187,22 @@ static void stsi_check_maxcpus(struct sysinfo_15_1_x *info)
>>>    }
>>>    
>>>    /*
>>> - * stsi_check_mag
>>> + * stsi_check_header
>>>     * @info: Pointer to the stsi information
>>> + * @sel2: stsi selector 2 value
>>>     *
>>>     * MAG field should match the architecture defined containers
>>>     * when MNEST as returned by SCLP matches MNEST of the SYSIB.
>>>     */
>>> -static void stsi_check_mag(struct sysinfo_15_1_x *info)
>>> +static void stsi_check_header(struct sysinfo_15_1_x *info, int sel2)
>>>    {
>>>    	int i;
>>>    
>>> -	report_prefix_push("MAG");
>>> +	report_prefix_push("Header");
>>>    
>>> +	report(IS_ALIGNED(info->length, 8), "Length %d multiple of 8", info->length);
>>
>> STSI 15 works on Words, not DWords, no?
>> So we need to check length against 4, not 8.
> 
> The header is 16 bytes.
> Topology list entries are 8 or 16, so it must be a multiple of 8 at least.

Fair enough

> 
>>
>>> +	report(info->length < PAGE_SIZE, "Length %d in bounds", info->length);
>>> +	report(sel2 == info->mnest, "Valid mnest");
>>>    	stsi_check_maxcpus(info);
>>>    
>>>    	/*
>>> @@ -326,7 +330,6 @@ static int stsi_get_sysib(struct sysinfo_15_1_x *info, int sel2)
>>>    
>>>    	if (max_nested_lvl >= sel2) {
>>>    		report(!ret, "Valid instruction");
>>> -		report(sel2 == info->mnest, "Valid mnest");
>>>    	} else {
>>>    		report(ret, "Invalid instruction");
>>>    	}
>>> @@ -365,7 +368,7 @@ static void check_sysinfo_15_1_x(struct sysinfo_15_1_x *info, int sel2)
>>>    		goto vertical;
>>>    	}
>>>    
>>> -	stsi_check_mag(info);
>>> +	stsi_check_header(info, sel2);
>>>    	stsi_check_tle_coherency(info);
>>>    
>>>    vertical:
>>> @@ -378,7 +381,7 @@ vertical:
>>>    		goto end;
>>>    	}
>>>    
>>> -	stsi_check_mag(info);
>>> +	stsi_check_header(info, sel2);
>>>    	stsi_check_tle_coherency(info);
>>>    	report_prefix_pop();
>>>    
>>
>