Subject: Re: [PATCH -next] sched: Use struct_size() helper in
 task_numa_group()
To:     Steven Rostedt <rostedt@goodmis.org>
CC:     <mingo@redhat.com>, <peterz@infradead.org>,
        <juri.lelli@redhat.com>, <vincent.guittot@linaro.org>,
        <dietmar.eggemann@arm.com>, <bsegall@google.com>,
        <mgorman@suse.de>, <bristot@redhat.com>, <gustavoars@kernel.org>,
        <linux-kernel@vger.kernel.org>, <linux-hardening@vger.kernel.org>
References: <20220107025212.177040-1-xiujianfeng@huawei.com>
 <20220107093617.56e218dc@gandalf.local.home>
From:   xiujianfeng <xiujianfeng@huawei.com>
Message-ID: <263460ee-c97f-73cf-fcbc-e47eb0e2905f@huawei.com>
Date:   Mon, 10 Jan 2022 09:20:33 +0800
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?? 2022/1/7 22:36, Steven Rostedt д??:
> On Fri, 7 Jan 2022 10:52:12 +0800
> Xiu Jianfeng <xiujianfeng@huawei.com> wrote:
>
>> Make use of struct_size() helper instead of an open-coded calculation.
>> There is no functional change in this patch.
>>
>> Link: https://github.com/KSPP/linux/issues/160
>> Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
>> ---
>>   kernel/sched/fair.c | 7 ++-----
>>   1 file changed, 2 insertions(+), 5 deletions(-)
>>
>> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
>> index 095b0aa378df..265e37be0c92 100644
>> --- a/kernel/sched/fair.c
>> +++ b/kernel/sched/fair.c
>> @@ -2437,11 +2437,8 @@ static void task_numa_group(struct task_struct *p, int cpupid, int flags,
>>   	int i;
>>   
>>   	if (unlikely(!deref_curr_numa_group(p))) {
>> -		unsigned int size = sizeof(struct numa_group) +
>> -				    NR_NUMA_HINT_FAULT_STATS *
>> -				    nr_node_ids * sizeof(unsigned long);
>> -
>> -		grp = kzalloc(size, GFP_KERNEL | __GFP_NOWARN);
>> +		grp = kzalloc(struct_size(grp, faults, NR_NUMA_HINT_FAULT_STATS * nr_node_ids),
>> +			      GFP_KERNEL | __GFP_NOWARN);
> I just replied yesterday. Keep the size variable. The above is too much for
> a kzalloc().

thanks, I may missed your reply mail, I'll modify and resend this patch.

>
> -- Steve
>
>
>
>
>>   		if (!grp)
>>   			return;
>>   
> .