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charset="iso-8859-1" Content-ID: <9B589E8022892A4FBFD8897D5CD8C2B1@namprd15.prod.outlook.com> Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-CrossTenant-Network-Message-Id: 2fb6a2d3-28bb-41ce-b7ff-08d6d33445f1 X-MS-Exchange-CrossTenant-originalarrivaltime: 07 May 2019 21:37:58.7565 (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-Transport-CrossTenantHeadersStamped: BYAPR15MB3461 X-OriginatorOrg: fb.com X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-05-07_12:,, signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1905070134 X-FB-Internal: deliver Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 07, 2019 at 04:04:22PM -0400, Qian Cai wrote: > LTP ptrace01 test case triggers a warning below. Looks at ptrace_stop() c= alls > cgroup_enter_frozen() there in the cgroup v2 freezer. >=20 > [ 8373.336330] WARNING: CPU: 56 PID: 67026 at kernel/cgroup/cgroup.c:6008 > cgroup_exit+0x2a9/0x2f0 > [ 8373.345001] Modules linked in: brd ext4 crc16 mbcache jbd2 overlay loo= p > nls_iso8859_1 nls_cp437 vfat fat kvm_amd kvm ses enclosure dax_pmem irqby= pass > dax_pmem_core efivars ip_tables x_tables xfs sd_mod smartpqi scsi_transpo= rt_sas > tg3 mlx5_core libphy firmware_class dm_mirror dm_region_hash dm_log dm_mo= d > efivarfs [last unloaded: dummy_del_mod] > [ 8373.375561] CPU: 56 PID: 67026 Comm: ptrace01 Tainted: > G=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0O=A0=A0=A0=A0=A0=A05.1.0-next-20190507+= #25 > [ 8373.384579] Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen= 10, > BIOS A40 01/25/2019 > [ 8373.393164] RIP: 0010:cgroup_exit+0x2a9/0x2f0 > [ 8373.397556] Code: 0d ff ff ff 4c 89 f7 e8 75 4b 1b 00 4c 8b ab 20 0f 0= 0 00 49 > 8d 7d 50 e8 65 4b 1b 00 49 8b 7d 50 e8 4c 56 00 00 e9 db fe ff ff <0f> 0b= e9 3a > fe ff ff 48 01 f1 0f 82 3b ff ff ff 48 c7 c7 40 83 5b > [ 8373.416443] RSP: 0018:ffff888bdc9ef9b8 EFLAGS: 00010002 > [ 8373.421709] RAX: 0000000000000000 RBX: ffff888e5cfcc040 RCX: ffffffffa= b3a8e7d > [ 8373.428897] RDX: 1ffff111cb9f9875 RSI: dffffc0000000000 RDI: ffff888e5= cfcc3a8 > [ 8373.436080] RBP: ffff888bdc9efa50 R08: ffffed117b93df25 R09: ffffed117= b93df24 > [ 8373.443266] R10: ffffed117b93df24 R11: 0000000000000003 R12: ffff888bd= c9efa28 > [ 8373.450451] R13: ffff888f4c2346c8 R14: ffff888e5cfccf60 R15: ffff888e5= cfccf68 > [ 8373.457637] FS:=A0=A000007ff1e2e3d5c0(0000) GS:ffff88902f800000(0000) > knlGS:0000000000000000 > [ 8373.465781] CS:=A0=A00010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 8373.471569] CR2: 00007ff1e286fe8a CR3: 000000092c412000 CR4: 000000000= 01406a0 > [ 8373.478750] Call Trace: > [ 8373.481219]=A0=A0? cgroup_post_fork+0x350/0x350 > [ 8373.485435]=A0=A0? fpu__drop+0x5e/0x230 > [ 8373.488951]=A0=A0? exit_thread+0x10c/0x160 > [ 8373.492736]=A0=A0do_exit+0x5cb/0x1740 > [ 8373.496083]=A0=A0? check_chain_key+0x142/0x200 > [ 8373.500210]=A0=A0? mm_update_next_owner+0x360/0x360 > [ 8373.504775]=A0=A0? map_id_up+0x14c/0x1f0 > [ 8373.508380]=A0=A0? check_chain_key+0x142/0x200 > [ 8373.512512]=A0=A0? get_signal+0x5f1/0xde0 > [ 8373.516206]=A0=A0? lock_downgrade+0x300/0x300 > [ 8373.520246]=A0=A0? lock_downgrade+0x300/0x300 > [ 8373.524287]=A0=A0do_group_exit+0x78/0x160 > [ 8373.527978]=A0=A0get_signal+0x1e8/0xde0 > [ 8373.531498]=A0=A0do_signal+0x9c/0x9d0 > [ 8373.534841]=A0=A0? check_chain_key+0x142/0x200 > [ 8373.538970]=A0=A0? setup_sigcontext+0x280/0x280 > [ 8373.543185]=A0=A0? lock_downgrade+0x300/0x300 > [ 8373.547228]=A0=A0? kill_pid_info+0x2e/0xd0 > [ 8373.551006]=A0=A0? kill_pid_info+0xa4/0xd0 > [ 8373.554788]=A0=A0? __x64_sys_kill+0x262/0x350 > [ 8373.558830]=A0=A0exit_to_usermode_loop+0x9d/0xc0 > [ 8373.563131]=A0=A0do_syscall_64+0x470/0x5d8 > [ 8373.566910]=A0=A0? syscall_return_slowpath+0xf0/0xf0 > [ 8373.571565]=A0=A0? __do_page_fault+0x44d/0x5b0 > [ 8373.575698]=A0=A0entry_SYSCALL_64_after_hwframe+0x44/0xa9 > [ 8373.580789] RIP: 0033:0x7ff1e2893c3b > [ 8373.584402] Code: Bad RIP value. > [ 8373.587653] RSP: 002b:00007ffd8e5efe78 EFLAGS: 00000206 ORIG_RAX: > 000000000000003e > [ 8373.595276] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007ff1e= 2893c3b > [ 8373.602461] RDX: 0000000000000000 RSI: 000000000000000c RDI: 000000000= 00105d2 > [ 8373.609642] RBP: 0000000000000000 R08: 00000000ffffffff R09: 00007ff1e= 2e3d5c0 > [ 8373.616824] R10: fffffffffffff768 R11: 0000000000000206 R12: 00007ffd8= e5efe98 > [ 8373.624005] R13: 00007ffd8e5f00c0 R14: 0000000000000000 R15: 000000000= 0000000 > [ 8373.631190] ---[ end trace a7169f3366f1d100 ]--- Hello, Qian! Thank you for the report! Can you, please, try if the following patch fixes the problem? Thank you! Roman -- diff --git a/kernel/signal.c b/kernel/signal.c index 16b72f4f14df..bf2f268f1386 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2484,9 +2484,6 @@ bool get_signal(struct ksignal *ksig) sigdelset(¤t->pending.signal, SIGKILL); recalc_sigpending(); current->jobctl &=3D ~JOBCTL_TRAP_FREEZE; - spin_unlock_irq(&sighand->siglock); - if (unlikely(cgroup_task_frozen(current))) - cgroup_leave_frozen(true); goto fatal; } =20 @@ -2608,8 +2605,10 @@ bool get_signal(struct ksignal *ksig) continue; } =20 - spin_unlock_irq(&sighand->siglock); fatal: + spin_unlock_irq(&sighand->siglock); + if (unlikely(cgroup_task_frozen(current))) + cgroup_leave_frozen(true); =20 /* * Anything else is fatal, maybe with a core dump.