From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Laight Subject: RE: bit fields && data tearing Date: Fri, 5 Sep 2014 12:37:17 +0000 Message-ID: <063D6719AE5E284EB5DD2968C1650D6D17488265@AcuExch.aculab.com> References: <54079B70.4050200@hurleysoftware.com> <1409785893.30640.118.camel@pasglop> <21512.10628.412205.873477@gargle.gargle.HOWL> <20140904090952.GW17454@tucnak.redhat.com> <540859EC.5000407@hurleysoftware.com> <20140904175044.4697aee4@alan.etchedpixels.co.uk> <5408C0AB.6050801@hurleysoftware.com> <20140905001751.GL5001@linux.vnet.ibm.com> <1409883098.5078.14.camel@jarvis.lan> <5409243C.4080704@hurleysoftware.com> <20140905040645.GO5001@linux.vnet.ibm.com> <063D6719AE5E284EB5DD2968C1650D6D17487F66@AcuExch.aculab.com> <5409AD0A.5090305@hurleysoftware.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <5409AD0A.5090305@hurleysoftware.com> Content-Language: en-US Sender: linux-ia64-owner@vger.kernel.org To: 'Peter Hurley' , "'paulmck@linux.vnet.ibm.com'" Cc: Jakub Jelinek , One Thousand Gnomes , "linux-arch@vger.kernel.org" , "linux-ia64@vger.kernel.org" , Mikael Pettersson , Oleg Nesterov , "linux-kernel@vger.kernel.org" , James Bottomley , Tony Luck , Paul Mackerras , "H. Peter Anvin" , "linuxppc-dev@lists.ozlabs.org" , Miroslav Franc , Richard Henderson , "linux-arm@vger.kernel.org" List-Id: linux-arch.vger.kernel.org RnJvbTogUGV0ZXIgSHVybGV5DQo+IFsgK2NjIGxpbnV4LWFybSBdDQo+IA0KPiBIaSBEYXZpZCwN Cj4gDQo+IE9uIDA5LzA1LzIwMTQgMDQ6MzAgQU0sIERhdmlkIExhaWdodCB3cm90ZToNCj4gPiBJ J3ZlIHNlZW4gZ2NjIGdlbmVyYXRlIDMyYml0IGFjY2Vzc2VzIGZvciAxNmJpdCBzdHJ1Y3R1cmUg bWVtYmVycyBvbiBhcm0uDQo+ID4gSXQgZG9lcyB0aGlzIGJlY2F1c2Ugb2YgdGhlIG1vcmUgbGlt aXRlZCByYW5nZSBvZiB0aGUgb2Zmc2V0cyBmb3IgdGhlIDE2Yml0IGFjY2Vzcy4NCj4gPiBPVE9I IEkgZG9uJ3Qga25vdyBpZiBpdCBldmVyIGRpZCB0aGlzIGZvciB3cml0ZXMgLSBzbyBpdCBtYXkg YmUgbW9vdC4NCj4gDQo+IENhbiB5b3UgcmVjYWxsIHRoZSBwYXJ0aWN1bGFycywgbGlrZSB3aGF0 IEFSTSBjb25maWcgb3Igd2hhdCBjb2RlPw0KPiANCj4gSSB0cmllZCBhbiBvdmVybHktc2ltcGxl IHRlc3QgdG8gc2VlIGlmIGdjYyB3b3VsZCBidW1wIHVwIHRvIHRoZSB3b3JkIGxvYWQgZm9yDQo+ IHRoZSAxMi1iaXQgb2Zmc2V0IG1vZGUsIGJ1dCBpdCBzdHVjayB3aXRoIHJlZ2lzdGVyIG9mZnNl dCByYXRoZXIgdGhhbiBpbW1lZGlhdGUNCj4gb2Zmc2V0LiBbSSB1c2VkIHRoZSBjb21waWxlciBv cHRpb25zIGZvciBhbGxtb2Rjb25maWcgYW5kIGEgNC44IGNyb3NzLWNvbXBpbGVyLl0NCj4gDQo+ IE1heWJlIHRoZSB0ZXN0IGRvZXNuJ3QgZ2VuZXJhdGUgZW5vdWdoIHJlZ2lzdGVyIHByZXNzdXJl IG9uIHRoZSBjb21waWxlcj8NCg0KRHVubm8sIEkgd291bGQgaGF2ZSBiZWVuIHVzaW5nIGEgbXVj aCBvbGRlciB2ZXJzaW9uIG9mIHRoZSBjb21waWxlci4NCkl0IGlzIHBvc3NpYmxlIHRoYXQgaXQg ZG9lc24ndCBkbyBpdCBhbnkgbW9yZS4NCkl0IG1pZ2h0IG9ubHkgaGF2ZSBkb25lIGl0IGZvciBs b2Fkcy4NCg0KVGhlIGNvbXBpbGVyIHVzZWQgdG8gdXNlIG1pc2FsaWduZWQgMzJiaXQgbG9hZHMg Zm9yIHN0cnVjdHVyZQ0KbWVtYmVycyBvbiBsYXJnZSA0bisyIGJ5dGUgYm91bmRhcmllcyBhcyB3 ZWxsLg0KSSdtIHByZXR0eSBzdXJlIGl0IGRvZXNuJ3QgZG8gdGhhdCBlaXRoZXIuDQoNClRoZXJl IGhhdmUgYmVlbiBhIGxvdCBvZiBjb21waWxlciB2ZXJzaW9ucyBzaW5jZSBJIHdhcyBjb21waWxp bmcNCmFueXRoaW5nIGZvciBhcm0uDQoNCglEYXZpZA0KDQo+IFJlZ2FyZHMsDQo+IFBldGVyIEh1 cmxleQ0KPiANCj4gI2RlZmluZSBBUlJBWV9TSVpFKHgpICAoc2l6ZW9mKHgpL3NpemVvZigoeClb MF0pKQ0KPiANCj4gc3RydWN0IHggew0KPiAJbG9uZyB1bnVzZWRbNjRdOw0KPiAJc2hvcnQgYlsx Ml07DQo+IAlpbnQgdW51c2VkMlsxMF07DQo+IAlzaG9ydCBjOw0KPiB9Ow0KPiANCj4gdm9pZCBz dG9yZV9jKHN0cnVjdCB4ICpwLCBzaG9ydCBhW10pIHsNCj4gCWludCBpOw0KPiANCj4gCWZvciAo aSA9IDA7IGkgPCBBUlJBWV9TSVpFKHAtPmIpOyBpKyspDQo+IAkJcC0+YltpXSA9IGFbaV07DQo+ IAlwLT5jID0gMjsNCj4gfQ0KPiANCj4gDQo+IHZvaWQgc3RvcmVfYyhzdHJ1Y3QgeCAqcCwgc2hv cnQgYVtdKSB7DQo+ICAgIDA6CWUxYTBjMDBkIAltb3YJaXAsIHNwDQo+ICAgIDQ6CWUzYTAzMDAw IAltb3YJcjMsICMwDQo+ICAgIDg6CWU5MmRkODAwIAlwdXNoCXtmcCwgaXAsIGxyLCBwY30NCj4g ICAgYzoJZTI0Y2IwMDQgCXN1YglmcCwgaXAsICM0DQo+IAlpbnQgaTsNCj4gDQo+IAlmb3IgKGkg PSAwOyBpIDwgQVJSQVlfU0laRShwLT5iKTsgaSsrKQ0KPiAJCXAtPmJbaV0gPSBhW2ldOw0KPiAg IDEwOgllMTkxYzBiMyAJbGRyaAlpcCwgW3IxLCByM10NCj4gICAxNDoJZTA4MDIwMDMgCWFkZAly MiwgcjAsIHIzDQo+ICAgMTg6CWUyODIyYzAxIAlhZGQJcjIsIHIyLCAjMjU2CTsgMHgxMDANCj4g ICAxYzoJZTI4MzMwMDIgCWFkZAlyMywgcjMsICMyDQo+ICAgMjA6CWUzNTMwMDE4IAljbXAJcjMs ICMyNA0KPiAgIDI0OgllMWMyYzBiMCAJc3RyaAlpcCwgW3IyXQ0KPiAgIDI4OgkxYWZmZmZmOCAJ Ym5lCTEwIDxzdG9yZV9jKzB4MTA+DQo+IAlwLT5jID0gMjsNCj4gICAyYzoJZTNhMDNkMDUgCW1v dglyMywgIzMyMAk7IDB4MTQwDQo+ICAgMzA6CWUzYTAyMDAyIAltb3YJcjIsICMyDQo+ICAgMzQ6 CWUxODAyMGIzIAlzdHJoCXIyLCBbcjAsIHIzXQ0KPiAgIDM4OgllODlkYTgwMCAJbGRtCXNwLCB7 ZnAsIHNwLCBwY30NCg0K From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0.aculab.com ([213.249.233.131]:46010 "HELO mx0.aculab.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1756877AbaIEMie (ORCPT ); Fri, 5 Sep 2014 08:38:34 -0400 Received: from mx0.aculab.com ([127.0.0.1]) by localhost (mx0.aculab.com [127.0.0.1]) (amavisd-new, port 10024) with SMTP id 02340-01 for ; Fri, 5 Sep 2014 13:38:25 +0100 (BST) From: David Laight Subject: RE: bit fields && data tearing Date: Fri, 5 Sep 2014 12:37:17 +0000 Message-ID: <063D6719AE5E284EB5DD2968C1650D6D17488265@AcuExch.aculab.com> References: <54079B70.4050200@hurleysoftware.com> <1409785893.30640.118.camel@pasglop> <21512.10628.412205.873477@gargle.gargle.HOWL> <20140904090952.GW17454@tucnak.redhat.com> <540859EC.5000407@hurleysoftware.com> <20140904175044.4697aee4@alan.etchedpixels.co.uk> <5408C0AB.6050801@hurleysoftware.com> <20140905001751.GL5001@linux.vnet.ibm.com> <1409883098.5078.14.camel@jarvis.lan> <5409243C.4080704@hurleysoftware.com> <20140905040645.GO5001@linux.vnet.ibm.com> <063D6719AE5E284EB5DD2968C1650D6D17487F66@AcuExch.aculab.com> <5409AD0A.5090305@hurleysoftware.com> In-Reply-To: <5409AD0A.5090305@hurleysoftware.com> Content-Language: en-US Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 MIME-Version: 1.0 Sender: linux-arch-owner@vger.kernel.org List-ID: To: 'Peter Hurley' , "'paulmck@linux.vnet.ibm.com'" Cc: Jakub Jelinek , One Thousand Gnomes , "linux-arch@vger.kernel.org" , "linux-ia64@vger.kernel.org" , Mikael Pettersson , Oleg Nesterov , "linux-kernel@vger.kernel.org" , James Bottomley , Tony Luck , Paul Mackerras , "H. Peter Anvin" , "linuxppc-dev@lists.ozlabs.org" , Miroslav Franc , Richard Henderson , "linux-arm@vger.kernel.org" Message-ID: <20140905123717.1BDE-i6Mjj3GYZP7uDmY_bxfPbyk9-Hp5WTMqwvhkyw@z> RnJvbTogUGV0ZXIgSHVybGV5DQo+IFsgK2NjIGxpbnV4LWFybSBdDQo+IA0KPiBIaSBEYXZpZCwN Cj4gDQo+IE9uIDA5LzA1LzIwMTQgMDQ6MzAgQU0sIERhdmlkIExhaWdodCB3cm90ZToNCj4gPiBJ J3ZlIHNlZW4gZ2NjIGdlbmVyYXRlIDMyYml0IGFjY2Vzc2VzIGZvciAxNmJpdCBzdHJ1Y3R1cmUg bWVtYmVycyBvbiBhcm0uDQo+ID4gSXQgZG9lcyB0aGlzIGJlY2F1c2Ugb2YgdGhlIG1vcmUgbGlt aXRlZCByYW5nZSBvZiB0aGUgb2Zmc2V0cyBmb3IgdGhlIDE2Yml0IGFjY2Vzcy4NCj4gPiBPVE9I IEkgZG9uJ3Qga25vdyBpZiBpdCBldmVyIGRpZCB0aGlzIGZvciB3cml0ZXMgLSBzbyBpdCBtYXkg YmUgbW9vdC4NCj4gDQo+IENhbiB5b3UgcmVjYWxsIHRoZSBwYXJ0aWN1bGFycywgbGlrZSB3aGF0 IEFSTSBjb25maWcgb3Igd2hhdCBjb2RlPw0KPiANCj4gSSB0cmllZCBhbiBvdmVybHktc2ltcGxl IHRlc3QgdG8gc2VlIGlmIGdjYyB3b3VsZCBidW1wIHVwIHRvIHRoZSB3b3JkIGxvYWQgZm9yDQo+ IHRoZSAxMi1iaXQgb2Zmc2V0IG1vZGUsIGJ1dCBpdCBzdHVjayB3aXRoIHJlZ2lzdGVyIG9mZnNl dCByYXRoZXIgdGhhbiBpbW1lZGlhdGUNCj4gb2Zmc2V0LiBbSSB1c2VkIHRoZSBjb21waWxlciBv cHRpb25zIGZvciBhbGxtb2Rjb25maWcgYW5kIGEgNC44IGNyb3NzLWNvbXBpbGVyLl0NCj4gDQo+ IE1heWJlIHRoZSB0ZXN0IGRvZXNuJ3QgZ2VuZXJhdGUgZW5vdWdoIHJlZ2lzdGVyIHByZXNzdXJl IG9uIHRoZSBjb21waWxlcj8NCg0KRHVubm8sIEkgd291bGQgaGF2ZSBiZWVuIHVzaW5nIGEgbXVj aCBvbGRlciB2ZXJzaW9uIG9mIHRoZSBjb21waWxlci4NCkl0IGlzIHBvc3NpYmxlIHRoYXQgaXQg ZG9lc24ndCBkbyBpdCBhbnkgbW9yZS4NCkl0IG1pZ2h0IG9ubHkgaGF2ZSBkb25lIGl0IGZvciBs b2Fkcy4NCg0KVGhlIGNvbXBpbGVyIHVzZWQgdG8gdXNlIG1pc2FsaWduZWQgMzJiaXQgbG9hZHMg Zm9yIHN0cnVjdHVyZQ0KbWVtYmVycyBvbiBsYXJnZSA0bisyIGJ5dGUgYm91bmRhcmllcyBhcyB3 ZWxsLg0KSSdtIHByZXR0eSBzdXJlIGl0IGRvZXNuJ3QgZG8gdGhhdCBlaXRoZXIuDQoNClRoZXJl IGhhdmUgYmVlbiBhIGxvdCBvZiBjb21waWxlciB2ZXJzaW9ucyBzaW5jZSBJIHdhcyBjb21waWxp bmcNCmFueXRoaW5nIGZvciBhcm0uDQoNCglEYXZpZA0KDQo+IFJlZ2FyZHMsDQo+IFBldGVyIEh1 cmxleQ0KPiANCj4gI2RlZmluZSBBUlJBWV9TSVpFKHgpICAoc2l6ZW9mKHgpL3NpemVvZigoeClb MF0pKQ0KPiANCj4gc3RydWN0IHggew0KPiAJbG9uZyB1bnVzZWRbNjRdOw0KPiAJc2hvcnQgYlsx Ml07DQo+IAlpbnQgdW51c2VkMlsxMF07DQo+IAlzaG9ydCBjOw0KPiB9Ow0KPiANCj4gdm9pZCBz dG9yZV9jKHN0cnVjdCB4ICpwLCBzaG9ydCBhW10pIHsNCj4gCWludCBpOw0KPiANCj4gCWZvciAo aSA9IDA7IGkgPCBBUlJBWV9TSVpFKHAtPmIpOyBpKyspDQo+IAkJcC0+YltpXSA9IGFbaV07DQo+ IAlwLT5jID0gMjsNCj4gfQ0KPiANCj4gDQo+IHZvaWQgc3RvcmVfYyhzdHJ1Y3QgeCAqcCwgc2hv cnQgYVtdKSB7DQo+ICAgIDA6CWUxYTBjMDBkIAltb3YJaXAsIHNwDQo+ICAgIDQ6CWUzYTAzMDAw IAltb3YJcjMsICMwDQo+ICAgIDg6CWU5MmRkODAwIAlwdXNoCXtmcCwgaXAsIGxyLCBwY30NCj4g ICAgYzoJZTI0Y2IwMDQgCXN1YglmcCwgaXAsICM0DQo+IAlpbnQgaTsNCj4gDQo+IAlmb3IgKGkg PSAwOyBpIDwgQVJSQVlfU0laRShwLT5iKTsgaSsrKQ0KPiAJCXAtPmJbaV0gPSBhW2ldOw0KPiAg IDEwOgllMTkxYzBiMyAJbGRyaAlpcCwgW3IxLCByM10NCj4gICAxNDoJZTA4MDIwMDMgCWFkZAly MiwgcjAsIHIzDQo+ICAgMTg6CWUyODIyYzAxIAlhZGQJcjIsIHIyLCAjMjU2CTsgMHgxMDANCj4g ICAxYzoJZTI4MzMwMDIgCWFkZAlyMywgcjMsICMyDQo+ICAgMjA6CWUzNTMwMDE4IAljbXAJcjMs ICMyNA0KPiAgIDI0OgllMWMyYzBiMCAJc3RyaAlpcCwgW3IyXQ0KPiAgIDI4OgkxYWZmZmZmOCAJ Ym5lCTEwIDxzdG9yZV9jKzB4MTA+DQo+IAlwLT5jID0gMjsNCj4gICAyYzoJZTNhMDNkMDUgCW1v dglyMywgIzMyMAk7IDB4MTQwDQo+ICAgMzA6CWUzYTAyMDAyIAltb3YJcjIsICMyDQo+ICAgMzQ6 CWUxODAyMGIzIAlzdHJoCXIyLCBbcjAsIHIzXQ0KPiAgIDM4OgllODlkYTgwMCAJbGRtCXNwLCB7 ZnAsIHNwLCBwY30NCg0K