Hi,
Yangbo Lu wrote:
>> -----Original Message-----
>> From: Richard Cochran [mailto:[email protected]]
>> Sent: Monday, February 22, 2016 4:48 PM
>> To: Yangbo Lu
>> Cc: [email protected]; Claudiu Manoil
>> Subject: Re: [PATCH 3/3] gianfar: fix endianness for hardware timestamp
>>
>> On Mon, Feb 22, 2016 at 02:49:33PM +0800, Yangbo Lu wrote:
>>> @@ -2708,6 +2708,7 @@ static void gfar_clean_tx_ring(struct
>> gfar_priv_tx_q *tx_queue)
>>> struct skb_shared_hwtstamps shhwtstamps;
>>> u64 *ns = (u64 *)(((uintptr_t)skb->data + 0x10) &
>>> ~0x7UL);
>>> + *ns = be64_to_cpu(*ns);
>>>
>>> memset(&shhwtstamps, 0, sizeof(shhwtstamps));
>>> shhwtstamps.hwtstamp = ns_to_ktime(*ns);
>>
>> There is no point in modifying the buffer data in place.
>>
>> Instead, do this:
>>
>> memset(&shhwtstamps, 0, sizeof(shhwtstamps));
>> shhwtstamps.hwtstamp = ns_to_ktime(be64_to_cpu(*ns));
>>
>> or this:
>>
>> u64 ns, *ptr = (u64 *)(((uintptr_t)skb->data + 0x10) &
>> ~0x7UL);
>> ns = be64_to_cpu(*ptr);
>>
>> memset(&shhwtstamps, 0, sizeof(shhwtstamps));
>> shhwtstamps.hwtstamp = ns_to_ktime(ns);
>>
>
> [Lu Yangbo-B47093] I will modify codes according your suggestion.
> Thank you so much!
You may want to use PTR_ALIGN() and be64_to_cpup() here.
--yoshfuji
>
>>> @@ -3037,6 +3038,7 @@ static void gfar_process_frame(struct net_device
>> *ndev, struct sk_buff *skb)
>>> if (priv->hwts_rx_en) {
>>> struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
>>> u64 *ns = (u64 *) skb->data;
>>> + *ns = be64_to_cpu(*ns);
>>>
>>> memset(shhwtstamps, 0, sizeof(*shhwtstamps));
>>> shhwtstamps->hwtstamp = ns_to_ktime(*ns);
>>
>> Same here.
>>
>> Thanks,
>> Richard
--
Hideaki Yoshifuji <[email protected]>
Technical Division, MIRACLE LINUX CORPORATION
