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charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: microsoft.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: BL0PR2101MB1026.namprd21.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 31002af5-1bb2-41d3-dd00-08dbc870daef X-MS-Exchange-CrossTenant-originalarrivaltime: 09 Oct 2023 02:38:43.7517 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 72f988bf-86f1-41af-91ab-2d7cd011db47 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: wNzzkHRxjubf+zKhG4Qby9+JHv3haH720z3GeBrm8roT379VTth50hPmaJHdGOInfOQ9vKC4+m5qG3LM4bcFzg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS7PR21MB3077 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org I retested with the following change as a sanity check:=0A= =0A= - BUG_ON(name->refcnt <=3D 0);=0A= + BUG_ON(atomic_read(&name->refcnt) <=3D 0);=0A= =0A= checkpatch.pl suggests using WARN_ON_ONCE rather than BUG.=0A= =0A= devvm ~ $ ~/linux/scripts/checkpatch.pl --patch ~/io_uring_audit_hang_atomi= c.patch =0A= WARNING: Do not crash the kernel unless it is absolutely unavoidable=0A= --use WARN_ON_ONCE() plus recovery code (if feasible) instead of BUG() or= variants=0A= #28: FILE: fs/namei.c:262:=0A= + BUG_ON(atomic_read(&name->refcnt) <=3D 0);=0A= ...=0A= =0A= refcount_t uses WARN_ON_ONCE.=0A= =0A= I can think of three choices:=0A= =0A= 1. Use atomic_t and remove the BUG line.=0A= 2. Use refcount_t and remove the BUG line. =0A= 3. Use atomic_t and partially implement the warn behavior of refcount_t.=0A= =0A= Choice 1 and 2 seem better than choice 3.=0A= =0A= =0A=