On 12/22/2022 9:52 AM, shaozhengchao wrote:
>
>
> On 2022/12/22 16:46, Kalle Valo wrote:
>> Sebastian Andrzej Siewior <[email protected]> writes:
>>
>>> On 2022-12-21 18:33:06 [+0000], Kalle Valo wrote:
>>>> Zhengchao Shao <[email protected]> wrote:
>>>>
>>>>> After the DMA buffer is mapped to a physical address, address is
>>>>> stored
>>>>> in pktids in brcmf_msgbuf_alloc_pktid(). Then, pktids is parsed in
>>>>> brcmf_msgbuf_get_pktid()/brcmf_msgbuf_release_array() to obtain
>>>>> physaddr
>>>>> and later unmap the DMA buffer. But when count is always equal to
>>>>> pktids->array_size, physaddr isn't stored in pktids and the DMA buffer
>>>>> will not be unmapped anyway.
>>>>>
>>>>> Fixes: 9a1bb60250d2 ("brcmfmac: Adding msgbuf protocol.")
>>>>> Signed-off-by: Zhengchao Shao <[email protected]>
>>>>
>>>> Can someone review this?
>>>
>>> After looking at the code, that skb is mapped but not inserted into the
>>> ringbuffer in this condition. The function returns with an error and the
>>> caller will free that skb (or add to a list for later). Either way the
>>> skb remains mapped which is wrong. The unmap here is the right thing to
>>> do.
>>>
>>> Reviewed-by: Sebastian Andrzej Siewior <[email protected]>
>>
>> Thanks for the review, very much appreciated.
>>
>
> Thank you very much.
Good catch. Has this path been observed or is this found by inspecting
the code? Just curious.
Regards,
Arend