Subject: Re: [PATCH V2] hyper-v: use GFP_KERNEL for hv_context.hv_numa_map
To: Stephen Hemminger <stephen@networkplumber.org>
Cc: kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com,
        devel@linuxdriverproject.org, linux-kernel@vger.kernel.org
References: <1513587772-8039-1-git-send-email-baijiaju1990@gmail.com>
 <20171218090529.5782a91d@xeon-e3>
From: Jia-Ju Bai <baijiaju1990@gmail.com>
Message-ID: <40ddf089-df5f-e6ae-6ec6-58849e6c9ceb@gmail.com>
Date: Tue, 19 Dec 2017 16:40:35 +0800
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On 2017/12/19 1:05, Stephen Hemminger wrote:
> On Mon, 18 Dec 2017 17:02:52 +0800
> Jia-Ju Bai <baijiaju1990@gmail.com> wrote:
>
>> The kzalloc function is called with GFP_ATOMIC.
>> But according to driver call graph, it is not in atomic context,
>> namely no spinlock is held nor in an interrupt handler.
>>
>> This GFP_ATOMIC is unnecessary, and replace with GFP_KERNEL.
>>
>> Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
>> ---
>>   drivers/hv/hv.c |    2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
>> index 8267439..b0d025a 100644
>> --- a/drivers/hv/hv.c
>> +++ b/drivers/hv/hv.c
>> @@ -150,7 +150,7 @@ int hv_synic_alloc(void)
>>   	int cpu;
>>   
>>   	hv_context.hv_numa_map = kzalloc(sizeof(struct cpumask) * nr_node_ids,
>> -					 GFP_ATOMIC);
>> +					 GFP_KERNEL);
>>   	if (hv_context.hv_numa_map == NULL) {
>>   		pr_err("Unable to allocate NUMA map\n");
>>   		goto err;
> Thanks, for fixing this.
> While you are at it; wouldn't it make sense to use kcalloc here?

I think kcalloc can be used here.


Thanks,
Jia-Ju Bai