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received-spf: None (protection.outlook.com: fb.com does not designate permitted sender hosts) x-microsoft-antispam-message-info: e/aGxsZsz94uVxzlu5zlElh+1heXZkWChUKnLzyhq47frnD7PCTMr82h3bqZOzYNJv8HwbN/IF2+LmTZ2AH0erZR9w10253D6Xy6aaOQUCl1QYjQiP+rzrfkyAAbHZM2ruZqpGEV44PdRfUZGOR7bW0peEWcX7kE0yUNPcH4i778AmwZNhBmItGlGAKZ897th6jnxcl6TqdFmSM/PYTIXEptnpBsKSajD1Ny+Z0/lCI0N61mIbqNbtbZB7BEYq0y26krD0Lh5ycuFFQaqbkaRTfcoDd2b2+hNFz5DFQRhhOlaPu/I6ncCV/HGJnjsTUutlXnsujkVOQbWe4OVVftSfVO+cQinhZecabzhZ3V8XE= spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM Content-Type: text/plain; charset="us-ascii" Content-ID: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-CrossTenant-Network-Message-Id: 56ec8af7-8648-443b-4471-08d64a581650 X-MS-Exchange-CrossTenant-originalarrivaltime: 14 Nov 2018 17:39:11.5774 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 8ae927fe-1255-47a7-a2af-5f3a069daaa2 X-MS-Exchange-Transport-CrossTenantHeadersStamped: BY2PR15MB0389 X-OriginatorOrg: fb.com X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-11-14_14:,, signatures=0 X-Proofpoint-Spam-Reason: safe X-FB-Internal: Safe Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 14, 2018 at 06:36:11PM +0100, Oleg Nesterov wrote: > On 11/14, Roman Gushchin wrote: > > > > > No, this is very wrong. Just suppose the caller is killed right befor= e > > > clear_thread_flag(TIF_SIGPENDING). > > > > So, I had TASK_KILLABLE before, but had some issues with ptrace/gdb. > > I'll revisit this option. >=20 > Yes, ptrace_signal_wake_up() won't wake a TASK_KILLABLE tracee up... >=20 > BTW. Could you explain in the changelog how should a frozen task interact > with ptrace? 0/6 says "ptrace works" but that is all. It is not clear to = me > what do we actually want wrt ptrace... Sure, will add. Basically, I want some minimal functionality to work properly. E.g. attach to a frozen task, get some info, detach.