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charset="us-ascii" Content-ID: <38ED7C80C49D5240B97A11B5C23CA12C@namprd15.prod.outlook.com> Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-CrossTenant-Network-Message-Id: 0ea07a06-7f10-4ced-d742-08d763d87fd6 X-MS-Exchange-CrossTenant-originalarrivaltime: 07 Nov 2019 23:16:20.3207 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 8ae927fe-1255-47a7-a2af-5f3a069daaa2 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: /z/QSD7vaOlLgKqw6IShYseX2Kin5WmqPYQN12fWs1cHitn4YBwWWXL3njm0meX+H0nmTZQEr/rK+pKNDjwM4g== X-MS-Exchange-Transport-CrossTenantHeadersStamped: MWHPR15MB1776 X-OriginatorOrg: fb.com X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.95,18.0.572 definitions=2019-11-07_07:2019-11-07,2019-11-07 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 lowpriorityscore=0 clxscore=1015 malwarescore=0 mlxlogscore=784 suspectscore=0 adultscore=0 mlxscore=0 bulkscore=0 phishscore=0 priorityscore=1501 impostorscore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-1911070214 X-FB-Internal: deliver Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org > On Nov 7, 2019, at 3:09 PM, Alexei Starovoitov wrote: >=20 > On Thu, Nov 07, 2019 at 11:07:21PM +0000, Song Liu wrote: >>=20 >>=20 >>>=20 >>>=20 >>>>> + >>>>> +static int bpf_trampoline_update(struct bpf_prog *prog) >>>>=20 >>>> Seems argument "prog" is not used at all?=20 >>>=20 >>> like one below ? ;) >> e... I was really dumb... sorry.. >>=20 >> Maybe we should just pass the tr in?=20 >=20 > that would be imbalanced. Hmm.. what do you mean by imbalanced? >=20 >>>=20 >>>>> +{ >>>>> + struct bpf_trampoline *tr =3D prog->aux->trampoline; >>>>> + void *old_image =3D tr->image + ((tr->selector + 1) & 1) * PAGE_SIZ= E/2; >>>>> + void *new_image =3D tr->image + (tr->selector & 1) * PAGE_SIZE/2; >>>>> + if (err) >>>>> + goto out; >>>>> + tr->selector++; >>>>=20 >>>> Shall we do selector-- for unlink? >>>=20 >>> It's a bit flip. I think it would be more confusing with -- >>=20 >> Right.. Maybe should use int instead of u64 for selector?=20 >=20 > No, since int can overflow. I guess it is OK to overflow, no?=