[PATCH v3 5/6] drm/i915/gvt: Assign NULL to the pointer after memory free.

Colin Xu Colin.Xu at intel.com
Thu Apr 25 05:31:40 UTC 2019


On 2019-04-25 11:14, Zhenyu Wang wrote:
> On 2019.04.23 15:04:12 +0300, Aleksei Gimbitskii wrote:
>> The klocwork static code analyzer complains about using pointer after
>> being freed, because further we pass it to the gvt_vgpu_err() function.
>> Assign pointer to be NULL intentionaly, to meet requirements of the code
>> analyzer.
>>
>> This patch fixed the issue #648 reported as error by klocwork.
>>
>> Signed-off-by: Aleksei Gimbitskii <aleksei.gimbitskii at intel.com>
>> Cc: Zhenyu Wang <zhenyuw at linux.intel.com>
>> Cc: Zhi Wang <zhi.a.wang at intel.com>
>> ---
>>   drivers/gpu/drm/i915/gvt/gtt.c | 1 +
>>   1 file changed, 1 insertion(+)
>>
>> diff --git a/drivers/gpu/drm/i915/gvt/gtt.c b/drivers/gpu/drm/i915/gvt/gtt.c
>> index 061499a38f4d..927753a59a1e 100644
>> --- a/drivers/gpu/drm/i915/gvt/gtt.c
>> +++ b/drivers/gpu/drm/i915/gvt/gtt.c
>> @@ -1106,6 +1106,7 @@ static struct intel_vgpu_ppgtt_spt *ppgtt_populate_spt_by_guest_entry(
>>   
>>   err_free_spt:
>>   	ppgtt_free_spt(spt);
>> +	spt = NULL;
>>   err:
>>   	gvt_vgpu_err("fail: shadow page %p guest entry 0x%llx type %d\n",
>>   		     spt, we->val64, we->type);
> I think we can remove this error message which doesn't tell the reason
> to fail at all, but have err message in earlier path where we can
> indicate the reason.

Seem like miss my comment in v2.

I would suggest add different msg before the two "goto err_free_spt",

then in this err_free_stp label you could just return without print the

same msg as err. Otherwise you can't tell the reason from the same err.

>
> _______________________________________________
> intel-gvt-dev mailing list
> intel-gvt-dev at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/intel-gvt-dev

-- 
Best Regards,
Colin Xu



More information about the intel-gvt-dev mailing list