Re: [PATCH v2 2/2] powerpc/pseries: Add failure related checks for h_get_mpp and h_get_ppp

[Shrikanth Hegde <sshegde@linux.ibm.com>]

On 8/16/24 01:23, Michal Suchánek wrote:
> On Fri, Apr 12, 2024 at 02:50:47PM +0530, Shrikanth Hegde wrote:
>> Couple of Minor fixes:
>>
>> - hcall return values are long. Fix that for h_get_mpp, h_get_ppp and
>> parse_ppp_data
>>
>> - If hcall fails, values set should be at-least zero. It shouldn't be
>> uninitialized values. Fix that for h_get_mpp and h_get_ppp
>>
>> Signed-off-by: Shrikanth Hegde <sshegde@linux.ibm.com>
>> ---
>>   arch/powerpc/include/asm/hvcall.h        | 2 +-
>>   arch/powerpc/platforms/pseries/lpar.c    | 6 +++---
>>   arch/powerpc/platforms/pseries/lparcfg.c | 6 +++---
>>   3 files changed, 7 insertions(+), 7 deletions(-)
>>
>> diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h
>> index a41e542ba94d..3d642139b900 100644
>> --- a/arch/powerpc/include/asm/hvcall.h
>> +++ b/arch/powerpc/include/asm/hvcall.h
>> @@ -570,7 +570,7 @@ struct hvcall_mpp_data {
>>   	unsigned long backing_mem;
>>   };
>>
>> -int h_get_mpp(struct hvcall_mpp_data *);
>> +long h_get_mpp(struct hvcall_mpp_data *mpp_data);
>>
>>   struct hvcall_mpp_x_data {
>>   	unsigned long coalesced_bytes;
>> diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c
>> index 4e9916bb03d7..c1d8bee8f701 100644
>> --- a/arch/powerpc/platforms/pseries/lpar.c
>> +++ b/arch/powerpc/platforms/pseries/lpar.c
>> @@ -1886,10 +1886,10 @@ notrace void __trace_hcall_exit(long opcode, long retval, unsigned long *retbuf)
>>    * h_get_mpp
>>    * H_GET_MPP hcall returns info in 7 parms
>>    */
>> -int h_get_mpp(struct hvcall_mpp_data *mpp_data)
>> +long h_get_mpp(struct hvcall_mpp_data *mpp_data)
>>   {
>> -	int rc;
>> -	unsigned long retbuf[PLPAR_HCALL9_BUFSIZE];
>> +	unsigned long retbuf[PLPAR_HCALL9_BUFSIZE] = {0};
>> +	long rc;
>>
>>   	rc = plpar_hcall9(H_GET_MPP, retbuf);
>>
>> diff --git a/arch/powerpc/platforms/pseries/lparcfg.c b/arch/powerpc/platforms/pseries/lparcfg.c
>> index 5c2a3e802a02..ed2176d8a866 100644
>> --- a/arch/powerpc/platforms/pseries/lparcfg.c
>> +++ b/arch/powerpc/platforms/pseries/lparcfg.c
>> @@ -113,8 +113,8 @@ struct hvcall_ppp_data {
>>    */
>>   static unsigned int h_get_ppp(struct hvcall_ppp_data *ppp_data)
> Hello,
> 
> Shouldn't the      ^^^ return value also be long?
> 
> Thanks
> 

Yes. You are right. missed to notice that. Thanks for pointing it out.

There might be other places where similar pattern maybe there.
Will fix it.

> Michal
>>   {
>> -	unsigned long rc;
>> -	unsigned long retbuf[PLPAR_HCALL9_BUFSIZE];
>> +	unsigned long retbuf[PLPAR_HCALL9_BUFSIZE] = {0};
>> +	long rc;
>>
>>   	rc = plpar_hcall9(H_GET_PPP, retbuf);
>>
>> @@ -197,7 +197,7 @@ static void parse_ppp_data(struct seq_file *m)
>>   	struct hvcall_ppp_data ppp_data;
>>   	struct device_node *root;
>>   	const __be32 *perf_level;
>> -	int rc;
>> +	long rc;
>>
>>   	rc = h_get_ppp(&ppp_data);
>>   	if (rc)
>> --
>> 2.39.3
>>