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received-spf: None (protection.outlook.com: fb.com does not designate permitted sender hosts) x-ms-exchange-senderadcheck: 1 x-microsoft-antispam-message-info: Fa5B4rLI0W81dRptYKbZE0arS3eYVCwbz3rYMnC3a1QwYfXbGOzssUG2kApOIB/BWDsKmBfvUXPIjzKhW58MmYC9TMFqBbo+qmaoNL4OoamN9P4Jcy9oeyuZ3uZzYGzBDipbu8FHh8SCLeqZyRcn6H0isuYDv3f1CiTWp7Yf/szStXF3FYYcCOqmXTUgSvjihPAoiBmDo4TPRIwFBGE86vU8bBsix+7v7nXNKzoe4LvsDj+Enf05ikkbgQ4oeIP9p1gevIpGbbLGCbqIPbc9vLmfz7GAGSrR4upoqLAlkisUf15lbMd6xCVSLkhgBLfWCnwjkO1/tiGeBCUJBrA0DQaeDPIxM8YWWE35Vj/ldmsTfZQURHWD6Zx6SiiNEeQ6C0OedEIrnUiUNqYRtPbEnESHzmCGknzATL8XFdt16SU= Content-Type: text/plain; charset="us-ascii" Content-ID: <55A513311A1D57409936E10272BF1017@namprd15.prod.outlook.com> Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-CrossTenant-Network-Message-Id: 22d92ab9-1f23-4e29-7dcb-08d69780c884 X-MS-Exchange-CrossTenant-originalarrivaltime: 20 Feb 2019 22:14:29.0224 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-id: 8ae927fe-1255-47a7-a2af-5f3a069daaa2 X-MS-Exchange-Transport-CrossTenantHeadersStamped: BYAPR15MB2693 X-OriginatorOrg: fb.com X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-02-20_17:,, 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, Feb 20, 2019 at 03:42:02PM +0100, Oleg Nesterov wrote: > On 02/19, Roman Gushchin wrote: > > > > @@ -2065,6 +2066,7 @@ static void ptrace_stop(int exit_code, int why, i= nt clear_code, kernel_siginfo_t > > preempt_disable(); > > read_unlock(&tasklist_lock); > > preempt_enable_no_resched(); > > + cgroup_enter_stopped(); > > freezable_schedule(); > > } else { > > /* > > @@ -2243,6 +2245,7 @@ static bool do_signal_stop(int signr) > > } > > =20 > > /* Now we don't run again until woken by SIGCONT or SIGKILL */ > > + cgroup_enter_stopped(); > > freezable_schedule(); > > return true; >=20 > Please see my reply to 0/7. Answered in that thread. >=20 > > @@ -2280,7 +2286,8 @@ static void do_jobctl_trap(void) > > !(signal->flags & SIGNAL_STOP_STOPPED)) > > signr =3D SIGTRAP; > > WARN_ON_ONCE(!signr); > > - ptrace_do_notify(signr, signr | (PTRACE_EVENT_STOP << 8), > > + ptrace_do_notify(signr, > > + signr | (PTRACE_EVENT_STOP << 8), > > CLD_STOPPED); >=20 > white-space cleanup? Sorry, a bogus change. Please, ignore it. >=20 > > @@ -2363,7 +2419,8 @@ bool get_signal(struct ksignal *ksig) > > * we should notify the parent, prepare_signal(SIGCONT) encodes > > * the CLD_ si_code into SIGNAL_CLD_MASK bits. > > */ > > - if (unlikely(signal->flags & SIGNAL_CLD_MASK)) { > > + if (unlikely(signal->flags & SIGNAL_CLD_MASK) & > > + !(current->jobctl & JOBCTL_TRAP_FREEZE)) { >=20 > Hmm, why? If a process is going from the stopped to the frozen state, it looks like it's better to delay parent's notification up to the moment when it will actually run. Thanks!