From: Zhangkun <zhangkun4jr@163.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mathias Nyman <mathias.nyman@intel.com>,
linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
Zhang Kun <zhangkun@cdjrlc.com>
Subject: Re: [PATCH] xhci: Remove unused value len from xhci_unmap_temp_buf
Date: Sun, 7 Mar 2021 09:14:26 +0800 [thread overview]
Message-ID: <3ad81fd6-e88e-f55b-fe82-ac7804bc354c@163.com> (raw)
In-Reply-To: <YEOs5w8AYutM27/u@kroah.com>
On 3/7/21 12:25 AM, Greg Kroah-Hartman wrote:
> On Sat, Mar 06, 2021 at 08:06:44PM +0800, zhangkun4jr@163.com wrote:
>> From: Zhang Kun <zhangkun@cdjrlc.com>
>>
>> The value assigned to len by sg_pcopy_from_buffer() never used for
>> anything, so remove it.
>>
>> Signed-off-by: Zhang Kun <zhangkun@cdjrlc.com>
>> ---
>> drivers/usb/host/xhci.c | 3 +--
>> 1 file changed, 1 insertion(+), 2 deletions(-)
>>
>> diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
>> index bd27bd670104..6ebda89d476c 100644
>> --- a/drivers/usb/host/xhci.c
>> +++ b/drivers/usb/host/xhci.c
>> @@ -1335,7 +1335,6 @@ static bool xhci_urb_temp_buffer_required(struct usb_hcd *hcd,
>>
>> static void xhci_unmap_temp_buf(struct usb_hcd *hcd, struct urb *urb)
>> {
>> - unsigned int len;
>> unsigned int buf_len;
>> enum dma_data_direction dir;
>>
>> @@ -1351,7 +1350,7 @@ static void xhci_unmap_temp_buf(struct usb_hcd *hcd, struct urb *urb)
>> dir);
>>
>> if (usb_urb_dir_in(urb))
>> - len = sg_pcopy_from_buffer(urb->sg, urb->num_sgs,
>> + sg_pcopy_from_buffer(urb->sg, urb->num_sgs,
>> urb->transfer_buffer,
>> buf_len,
>> 0);
>
> SHouldn't this be checked instead of ignored?
>
Hi, Greg.
Considering your tips I checked sg_pcopy_from_buffer(). it copys data
from urb->transfer_buffer to urb->sg, and only returns 0 or the
'number of copied bytes', and seems to has no other exception branchs
that need to be checked. So I think it should be ingnored.
It may also be that I missed something, if that's the case, please
correct me.
Thanks,
Zhang
next prev parent reply other threads:[~2021-03-07 1:19 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-06 12:06 [PATCH] xhci: Remove unused value len from xhci_unmap_temp_buf zhangkun4jr
2021-03-06 16:25 ` Greg Kroah-Hartman
2021-03-07 1:14 ` Zhangkun [this message]
2021-03-09 13:22 ` Greg Kroah-Hartman
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