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McKenney" , Randy Dunlap , "stable@vger.kernel.org" Subject: RE: [PATCH] list: Prevent compiler reloads inside 'safe' list iteration Thread-Topic: [PATCH] list: Prevent compiler reloads inside 'safe' list iteration Thread-Index: AQHV9r1KBrT+D4Vo2U+Op9v/Nv0od6hBsdzwgAAEwQCAAAWYAA== Date: Tue, 10 Mar 2020 12:23:34 +0000 Message-ID: <723d527a4ad349b78bf11d52eba97c0e@AcuMS.aculab.com> References: <20200310092119.14965-1-chris@chris-wilson.co.uk> <2e936d8fd2c445beb08e6dd3ee1f3891@AcuMS.aculab.com> <158384100886.16414.15741589015363013386@build.alporthouse.com> In-Reply-To: <158384100886.16414.15741589015363013386@build.alporthouse.com> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: base64 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org RnJvbTogQ2hyaXMgV2lsc29uDQo+IFNlbnQ6IDEwIE1hcmNoIDIwMjAgMTE6NTANCj4gDQo+IFF1 b3RpbmcgRGF2aWQgTGFpZ2h0ICgyMDIwLTAzLTEwIDExOjM2OjQxKQ0KPiA+IEZyb206IENocmlz IFdpbHNvbg0KPiA+ID4gU2VudDogMTAgTWFyY2ggMjAyMCAwOToyMQ0KPiA+ID4gSW5zdHJ1Y3Qg dGhlIGNvbXBpbGVyIHRvIHJlYWQgdGhlIG5leHQgZWxlbWVudCBpbiB0aGUgbGlzdCBpdGVyYXRp b24NCj4gPiA+IG9uY2UsIGFuZCB0aGF0IGl0IGlzIG5vdCBhbGxvd2VkIHRvIHJlbG9hZCB0aGUg dmFsdWUgZnJvbSB0aGUgc3RhbGUNCj4gPiA+IGVsZW1lbnQgbGF0ZXIuIFRoaXMgaXMgaW1wb3J0 YW50IGFzIGR1cmluZyB0aGUgY291cnNlIG9mIHRoZSBzYWZlDQo+ID4gPiBpdGVyYXRpb24sIHRo ZSBzdGFsZSBlbGVtZW50IG1heSBiZSBwb2lzb25lZCAodW5iZWtub3duc3QgdG8gdGhlDQo+ID4g PiBjb21waWxlcikuDQo+ID4NCj4gPiBFaD8NCj4gPiBJIHRob3VnaHQgYW55IGZ1bmN0aW9uIGNh bGwgd2lsbCBzdG9wIHRoZSBjb21waWxlciBiZWluZyBhbGxvd2VkDQo+ID4gdG8gcmVsb2FkIHRo ZSB2YWx1ZS4NCj4gPiBUaGUgJ3NhZmUnIGxvb3AgaXRlcmF0b3JzIGFyZSBvbmx5ICdzYWZlJyBh Z2FpbnN0IGNhbGxlZA0KPiA+IGNvZGUgcmVtb3ZpbmcgdGhlIGN1cnJlbnQgaXRlbSBmcm9tIHRo ZSBsaXN0Lg0KPiA+DQo+ID4gPiBUaGlzIGhlbHBzIHByZXZlbnQga2NzYW4gd2FybmluZ3Mgb3Zl ciAndW5zYWZlJyBjb25kdWN0IGluIHJlbGVhc2luZyB0aGUNCj4gPiA+IGxpc3QgZWxlbWVudHMg ZHVyaW5nIGxpc3RfZm9yX2VhY2hfZW50cnlfc2FmZSgpIGFuZCBmcmllbmRzLg0KPiA+DQo+ID4g U291bmRzIGxpa2Uga2NzYW4gaXMgYnVnZ3kgPz8/Pw0KPiANCj4gVGhlIHdhcm5pbmcga2NzYW4g Z2F2ZSBtYWRlIHNlbnNlIChhIHN0cmFuZ2UgY2FzZSB3aGVyZSB0aGUgZW1wdHlpbmcgdGhlDQo+ IGxpc3QgZnJvbSBpbnNpZGUgdGhlIHNhZmUgaXRlcmF0b3Igd291bGQgYWxsb3cgdGhhdCBsaXN0 IHRvIGJlIHRha2VuDQo+IHVuZGVyIGEgZ2xvYmFsIG11dGV4IGFuZCBoYXZlIG9uZSBleHRyYSBy ZXF1ZXN0IGFkZGVkIHRvIGl0LiBUaGUNCj4gbGlzdF9mb3JfZWFjaF9lbnRyeV9zYWZlKCkgc2hv dWxkIGJlIG9rIGluIHRoaXMgc2NlbmFyaW8sIHNvIGxvbmcgYXMgdGhlDQo+IG5leHQgZWxlbWVu dCBpcyByZWFkIGJlZm9yZSB0aGlzIGVsZW1lbnQgaXMgZHJvcHBlZCwgYW5kIHRoZSBjb21waWxl ciBpcw0KPiBpbnN0cnVjdGVkIG5vdCB0byByZWxvYWQgdGhlIGVsZW1lbnQuDQoNCk5vcm1hbGx5 IHRoZSBsb29wIGl0ZXJhdGlvbiBjb2RlIGhhcyB0byBob2xkIHRoZSBtdXRleC4NCkkgZ3Vlc3Mg aXQgY2FuIGJlIHJlbGVhc2VkIGluc2lkZSB0aGUgbG9vcCBwcm92aWRlZCBubyBvdGhlcg0KY29k ZSBjYW4gZXZlciBkZWxldGUgZW50cmllcy4NCg0KPiBrY3NhbiBpcyBhIGxpdHRsZSBtb3JlIGlu c2lzdGVudCBvbiBoYXZpbmcgdGhhdCBhbm5vdGF0aW9uIDopDQo+IA0KPiBJbiB0aGlzIGluc3Rh bmNlIEkgd291bGQgc2F5IGl0IHdhcyBhIGZhbHNlIHBvc2l0aXZlIGZyb20ga2NzYW4sIGJ1dCBJ DQo+IGNhbiBzZWUgd2h5IGl0IHdvdWxkIGNvbXBsYWluIGFuZCBzdXNwZWN0IHRoYXQgZ2l2ZW4g YSBzdWZmaWNpZW50bHkNCj4gYWdncmVzc2l2ZSBjb21waWxlciwgd2UgbWF5IGJlIGNhdWdodCBv dXQgYnkgYSBsYXRlIHJlbG9hZCBvZiB0aGUgbmV4dA0KPiBlbGVtZW50Lg0KDQpJZiB5b3UgaGF2 ZToNCglmb3IgKDsgcDsgcCA9IG5leHQpIHsNCgkJbmV4dCA9IHAtPm5leHQ7DQoJCWV4dGVybmFs X2Z1bmN0aW9uX2NhbGwodm9pZCk7DQoJfQ0KdGhlIGNvbXBpbGVyIG11c3QgYXNzdW1lIHRoYXQg dGhlIGZ1bmN0aW9uIGNhbGwNCmNhbiBjaGFuZ2UgJ3AtPm5leHQnIGFuZCByZWFkIGl0IGJlZm9y ZSB0aGUgY2FsbC4NCg0KSXMgdGhpcyBhIGxpc3Qgd2l0aCBzdHJhbmdlIGxvY2tpbmcgcnVsZXM/ DQpUaGUgb25seSBkZWxldGVzIGFyZSBmcm9tIHdpdGhpbiB0aGUgbG9vcC4NCkFkZHMgYW5kIGRl bGV0ZXMgYXJlIGxvY2tlZC4NClRoZSBsaXN0IHRyYXZlcnNhbCBpc24ndCBsb2NrZWQuDQoNCkkg c3VzcGVjdCBrY3NhbiBibGVhdHMgYmVjYXVzZSBpdCBkb2Vzbid0IGFzc3VtZSB0aGUgY29tcGls ZXINCndpbGwgdXNlIGEgc2luZ2xlIGluc3RydWN0aW9uL21lbW9yeSBvcGVyYXRpb24gdG8gcmVh ZCBwLT5uZXh0Lg0KVGhhdCBpcyBqdXN0IHN0dXBpZC4NCg0KCURhdmlkDQoNCg0KDQoJCQ0KDQot DQpSZWdpc3RlcmVkIEFkZHJlc3MgTGFrZXNpZGUsIEJyYW1sZXkgUm9hZCwgTW91bnQgRmFybSwg TWlsdG9uIEtleW5lcywgTUsxIDFQVCwgVUsNClJlZ2lzdHJhdGlvbiBObzogMTM5NzM4NiAoV2Fs ZXMpDQo=