From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eu-smtp-delivery-151.mimecast.com (eu-smtp-delivery-151.mimecast.com [185.58.85.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0047BC1 for ; Fri, 1 Dec 2023 10:30:22 -0800 (PST) Received: from AcuMS.aculab.com (156.67.243.121 [156.67.243.121]) by relay.mimecast.com with ESMTP with both STARTTLS and AUTH (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id uk-mta-64-l9Pbyyc5NbCVu4Mqkqv9Yg-1; Fri, 01 Dec 2023 18:30:13 +0000 X-MC-Unique: l9Pbyyc5NbCVu4Mqkqv9Yg-1 Received: from AcuMS.Aculab.com (10.202.163.4) by AcuMS.aculab.com (10.202.163.4) with Microsoft SMTP Server (TLS) id 15.0.1497.48; Fri, 1 Dec 2023 18:30:05 +0000 Received: from AcuMS.Aculab.com ([::1]) by AcuMS.aculab.com ([::1]) with mapi id 15.00.1497.048; Fri, 1 Dec 2023 18:30:05 +0000 From: David Laight To: 'Jann Horn' , Jens Axboe , "Pavel Begunkov" , io-uring CC: kernel list , Peter Zijlstra , Ingo Molnar , Will Deacon , Waiman Long Subject: RE: io_uring: incorrect assumption about mutex behavior on unlock? Thread-Topic: io_uring: incorrect assumption about mutex behavior on unlock? Thread-Index: AQHaJHVMNn8At2QRcESH/qhfYed73LCUvC/Q Date: Fri, 1 Dec 2023 18:30:05 +0000 Message-ID: <811a97651e144b83a35fd7eb713aeeae@AcuMS.aculab.com> References: In-Reply-To: Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: base64 RnJvbTogSmFubiBIb3JuDQo+IFNlbnQ6IDAxIERlY2VtYmVyIDIwMjMgMTY6NDENCj4gDQo+IG11 dGV4X3VubG9jaygpIGhhcyBhIGRpZmZlcmVudCBBUEkgY29udHJhY3QgY29tcGFyZWQgdG8gc3Bp bl91bmxvY2soKS4NCj4gc3Bpbl91bmxvY2soKSBjYW4gYmUgdXNlZCB0byByZWxlYXNlIG93bmVy c2hpcCBvZiBhbiBvYmplY3QsIHNvIHRoYXQNCj4gYXMgc29vbiBhcyB0aGUgc3BpbmxvY2sgaXMg dW5sb2NrZWQsIGFub3RoZXIgdGFzayBpcyBhbGxvd2VkIHRvIGZyZWUNCj4gdGhlIG9iamVjdCBj b250YWluaW5nIHRoZSBzcGlubG9jay4NCj4gbXV0ZXhfdW5sb2NrKCkgZG9lcyBub3Qgc3VwcG9y dCB0aGlzIGtpbmQgb2YgdXNhZ2U6IFRoZSBjYWxsZXIgb2YNCj4gbXV0ZXhfdW5sb2NrKCkgbXVz dCBlbnN1cmUgdGhhdCB0aGUgbXV0ZXggc3RheXMgYWxpdmUgdW50aWwNCj4gbXV0ZXhfdW5sb2Nr KCkgaGFzIHJldHVybmVkLg0KDQpUaGUgcHJvYmxlbSBzZXF1ZW5jZSBtaWdodCBiZToNCglUaHJl YWQgQQkJVGhyZWFkIEINCgltdXRleF9sb2NrKCkNCgkJCQljb2RlIHRvIHN0b3AgbXV0ZXggYmVp bmcgcmVxdWVzdGVkDQoJCQkJLi4uDQoJCQkJbXV0ZXhfbG9jaygpIC0gc2xlZXBzDQoJbXV0ZXhf dW5sb2NrKCkuLi4NCgkJV2FpdGVycyB3b2tlbi4uLg0KCQlpc3IgYW5kL29yIHByZS1lbXB0ZWQN CgkJCQktIHdha2VzIHVwDQoJCQkJbXV0ZXhfdW5sb2NrKCkNCgkJCQlmcmVlKCkNCgkJLi4uIG1v cmUga2VybmVsIGNvZGUgYWNjZXNzIHRoZSBtdXRleA0KCQlCT09PTQ0KDQpXaGF0IGhhcHBlbnMg aW4gYSBQUkVFTVBUX1JUIGtlcm5lbCB3aGVyZSBtb3N0IG9mIHRoZSBzcGluX3VubG9jaygpDQpn ZXQgcmVwbGFjZWQgYnkgbXV0ZXhfdW5sb2NrKCkuDQpTZWVtcyBsaWtlIHRoZXkgY2FuIHBvdGVu dGlhbGx5IGFjY2VzcyBhIGZyZWVkIG11dGV4Pw0KDQoJRGF2aWQNCg0KLQ0KUmVnaXN0ZXJlZCBB ZGRyZXNzIExha2VzaWRlLCBCcmFtbGV5IFJvYWQsIE1vdW50IEZhcm0sIE1pbHRvbiBLZXluZXMs IE1LMSAxUFQsIFVLDQpSZWdpc3RyYXRpb24gTm86IDEzOTczODYgKFdhbGVzKQ0K