Return-Path: linux-nfs-owner@vger.kernel.org Received: from mx2.netapp.com ([216.240.18.37]:34120 "EHLO mx2.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754290Ab2LLQaf (ORCPT ); Wed, 12 Dec 2012 11:30:35 -0500 From: "Myklebust, Trond" To: Fred Isaman CC: Jeff Layton , "linux-nfs@vger.kernel.org" , "eguan@redhat.com" Subject: Re: non-aligned DIO reads on NFS are corrupting memory in 3.7.0 Date: Wed, 12 Dec 2012 16:30:30 +0000 Message-ID: <4FA345DA4F4AE44899BD2B03EEEC2FA9119261B6@SACEXCMBX04-PRD.hq.netapp.com> References: <20121212094654.5ce53d89@tlielax.poochiereds.net> In-Reply-To: Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Sender: linux-nfs-owner@vger.kernel.org List-ID: T24gV2VkLCAyMDEyLTEyLTEyIGF0IDExOjIwIC0wNTAwLCBGcmVkIElzYW1hbiB3cm90ZToNCj4g T24gV2VkLCBEZWMgMTIsIDIwMTIgYXQgOTo0NiBBTSwgSmVmZiBMYXl0b24gPGpsYXl0b25AcmVk aGF0LmNvbT4gd3JvdGU6DQo+ID4gT25lIG9mIG91ciBRQSBmb2xrcyBmb3VuZCB0aGF0IHRoZSBh dHRhY2hlZCB0ZXN0Y2FzZSB3b3VsZCBzZWdmYXVsdA0KPiA+IHdoZW4gcnVuIG9uIGEgcmVjZW50 IHJoZWw2IGtlcm5lbCB0aGF0IGhhcyBhIGJhY2twb3J0IG9mIHRoZSBwbmZzIGRpbw0KPiA+IGNv ZGUuIEkgZ2V0IHRoZSBzYW1lIHNlZ2ZhdWx0IHdoZW4gSSBydW4gaXQgb24gYSAzLjcuMCBrZXJu ZWwgYXMgd2VsbC4NCj4gPg0KPiA+IEkgdGhpbmsgdGhlIHByb2JsZW0gaXMgdGhhdCBiZWNhdXNl IHRoZSBidWZmZXIgd2UncmUgcmVhZGluZyBpbnRvIGlzIG9uDQo+ID4gdGhlIHN0YWNrLCB0aGUg a2VybmVsIGlzIHNjcmliYmxpbmcgb3ZlciB0aGUgcmVzdCBvZiB0aGUgcGFnZSBhZnRlciB0aGUN Cj4gPiByZWFkIGFuZCBjb3JydXB0aW5nIGl0Lg0KPiA+DQo+ID4gVGhlIHByb2JsZW0sIEkgdGhp bmsgaXMgdGhpcyBibG9jayBpbiBuZnNfZGlyZWN0X3JlYWRfY29tcGxldGlvbigpOg0KPiA+DQo+ ID4gLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS1bc25pcF0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLQ0K PiA+ICAgICAgICAgICAgICAgICBpZiAodGVzdF9iaXQoTkZTX0lPSERSX0VPRiwgJmhkci0+Zmxh Z3MpKSB7DQo+ID4gICAgICAgICAgICAgICAgICAgICAgICAgaWYgKGJ5dGVzID4gaGRyLT5nb29k X2J5dGVzKQ0KPiA+ICAgICAgICAgICAgICAgICAgICAgICAgICAgICAgICAgemVyb191c2VyKHBh Z2UsIDAsIFBBR0VfU0laRSk7DQo+ID4gICAgICAgICAgICAgICAgICAgICAgICAgZWxzZSBpZiAo aGRyLT5nb29kX2J5dGVzIC0gYnl0ZXMgPCBQQUdFX1NJWkUpDQo+ID4gICAgICAgICAgICAgICAg ICAgICAgICAgICAgICAgICB6ZXJvX3VzZXJfc2VnbWVudChwYWdlLA0KPiA+ICAgICAgICAgICAg ICAgICAgICAgICAgICAgICAgICAgICAgICAgICBoZHItPmdvb2RfYnl0ZXMgJiB+UEFHRV9NQVNL LA0KPiA+ICAgICAgICAgICAgICAgICAgICAgICAgICAgICAgICAgICAgICAgICBQQUdFX1NJWkUp Ow0KPiA+ICAgICAgICAgICAgICAgICB9DQo+ID4gLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS1bc25p cF0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLQ0KPiA+DQo+ID4gSWYgSSBjb21tZW50IHRoYXQgb3V0 LCB0aGVuIHRoZSB0ZXN0IHBhc3NlcyBhbmQgaXQgZG9lc24ndCBzY3JpYmJsZQ0KPiA+IG92ZXIg bWVtb3J5LiBJJ20gbm90IGNsZWFyIG9uIHdoYXQgdGhhdCBibG9jayBpcyB0cnlpbmcgdG8gYWNj b21wbGlzaC4NCj4gPiBJZiB3ZSBnZXQgYSBzaG9ydCByZWFkIGluIHRoZSBESU8gY29kZXBhdGgs IEkgZG9uJ3QgdGhpbmsgd2Ugb3VnaHQgdG8NCj4gPiBiZSB6ZXJvaW5nIG91dCB0aGUgcmVzdCBv ZiB0aGUgcGFnZS4gV2Ugc2hvdWxkIGp1c3QgcmV0dXJuIHRoZSBudW1iZXINCj4gPiBvZiBieXRl cyByZWFkIGFuZCBiZSBkb25lIHdpdGggaXQuDQo+ID4NCj4gDQo+IEkgd291bGQgc2F5IHRoZSBw cm9ibGVtIGlzIG5vdCB6ZXJvaW5nIG1lbW9yeSwgYnV0IHRoYXQgdGhlIGNvZGUgaXNuJ3QNCj4g dGFraW5nIGludG8gYWNjb3VudCB0aGUgb2Zmc2V0cyBpbnRvIHRoZSBwYWdlLg0KDQpUaGUgbWVt b3J5IHJlZ2lvbiBsaWVzIGFmdGVyIHRoZSBFT0YsIHNvIHdlJ3JlIG5vdCBjb3VudGluZyBpdCBp bg0KZHJlcS0+Y291bnQuIE1vcmUgaW1wb3J0YW50bHksIGl0IHdvbid0IGJlIGFjY291bnRlZCBm b3IgaW4gdGhlIHJlYWQoKQ0Kc3lzdGVtIGNhbGwgcmV0dXJuIHZhbHVlLCBzbyBJIHRoaW5rIHdl IHNob3VsZCBhdm9pZCB0b3VjaGluZyBpdC4NCg0KPiA+IEknbSBhbHNvIHN1c3BpY2lvdXMgb2Yg dGhlICJpZiAoIVBhZ2VDb21wb3VuZChwYWdlKSkiIGNoZWNrIGluIHRoYXQNCj4gPiBmdW5jdGlv biBhcyB3ZWxsLiBJdCBkb2Vzbid0IHNlZW0gbGlrZSB3ZSBvdWdodCB0byBiZSBtYXJraW5nIHBh Z2VzDQo+ID4gZGlydHkgaW4gdGhlIERJTyBjb2RlcGF0aHMsIHNob3VsZCB3ZT8NCj4gPg0KPiA+ IC0tDQo+ID4gSmVmZiBMYXl0b24gPGpsYXl0b25AcmVkaGF0LmNvbT4NCj4gDQo+IEknbSBub3Qg c3VyZSBpZiB3ZSBzaG91bGQsIGJ1dCBjb2RlIHRvIGRvIHNvIGhhcyBiZWVuIGFyb3VuZCBmb3Jl dmVyLg0KPiBUaGUgZXhjZXB0aW9uIGZvciBQYWdlQ29tcG91bmQgaXMgZnJvbSBjb21taXQgNTY2 ZGQ2MDY0ZTg5YiAiTkZTOiBNYWtlDQo+IGRpcmVjdElPIGF3YXJlIG9mIGNvbXBvdW5kIHBhZ2Vz IiwgYWxtb3N0IDcgeWVhcnMgYWdvLg0KDQpSaWdodC4gVGhlIGNvZGUgZm9yIGRvaW5nIHRoaXMg Z29lcyBiYWNrIHRvIHRoZSBvcmlnaW5hbCBPX0RJUkVDVA0KaW1wbGVtZW50YXRpb24gaW4gMjAw My4gSUlSQywgQW5kcmV3IE1vcnRvbiBhc2tlZCB1cyB0byBkbyBpdCBpbiBvcmRlcg0KdG8gbWFr ZSB0aGluZ3MgbGlrZSBPX0RJUkVDVCByZWFkIGludG8gYW4gbW1hcHBlZCBtZW1vcnkgcmVnaW9u IHdvcmsNCmNvcnJlY3RseS4NCg0KLS0gDQpUcm9uZCBNeWtsZWJ1c3QNCkxpbnV4IE5GUyBjbGll bnQgbWFpbnRhaW5lcg0KDQpOZXRBcHANClRyb25kLk15a2xlYnVzdEBuZXRhcHAuY29tDQp3d3cu bmV0YXBwLmNvbQ0K