Re: [PATCH V7 7/9] PCI/sysfs: Add a 10-Bit Tag sysfs file

Dongdong Liu
2021-08-05T08:38:58Z

On 2021/8/5 7:52, Bjorn Helgaas wrote:
> On Wed, Aug 04, 2021 at 09:47:06PM +0800, Dongdong Liu wrote:
>> PCIe spec 5.0 r1.0 section 2.2.6.2 says that if an Endpoint supports
>> sending Requests to other Endpoints (as opposed to host memory), the
>> Endpoint must not send 10-Bit Tag Requests to another given Endpoint
>> unless an implementation-specific mechanism determines that the Endpoint
>> supports 10-Bit Tag Completer capability. Add a 10bit_tag sysfs file,
>> write 0 to disable 10-Bit Tag Requester when the driver does not bind
>> the device if the peer device does not support the 10-Bit Tag Completer.
>> This will make P2P traffic safe. the 10bit_tag file content indicate
>> current 10-Bit Tag Requester Enable status.
>>
>> Signed-off-by: Dongdong Liu <liudongdong3@huawei.com>
>
>> + The file is also writeable, the value only accept by write 0
>> + to disable 10-Bit Tag Requester when the driver does not bind
>> + the deivce. The typical use case is for p2pdma when the peer
>> + device does not support 10-BIT Tag Completer.
>
> s/10-BIT/10-Bit/
Will fix and will check other place.

Thank,
Dongdong
> .
>