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Shutemov" , "x86@kernel.org" , Thomas Gleixner , Peter Zijlstra , Pawan Gupta , Waiman Long , "Dave Hansen" , Ingo Molnar , "Michael Ellerman" , "linuxppc-dev@lists.ozlabs.org" , Mark Rutland Subject: RE: [PATCH] x86/uaccess: Avoid barrier_nospec() in copy_from_user() Thread-Topic: [PATCH] x86/uaccess: Avoid barrier_nospec() in copy_from_user() Thread-Index: AQHbJYiO0jpEiXw2TU+KrR/vXcxF6bKVniVg Date: Thu, 24 Oct 2024 09:21:56 +0000 Message-ID: References: <20241014035436.nsleqolyj3xxysrr@treble> <064d7068-c666-49f0-b7df-774c2e281abc@citrix.com> <20241020224444.zhoscljpe7di5yv3@treble> <20241020231112.erso2jzqwkbin4kh@treble> <20241023094448.GAZxjFkEOOF_DM83TQ@fat_crate.local> In-Reply-To: Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , 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 RnJvbTogTGludXMgVG9ydmFsZHMNCj4gU2VudDogMjMgT2N0b2JlciAyMDI0IDIxOjA4DQo+IA0K PiBPbiBXZWQsIDIzIE9jdCAyMDI0IGF0IDEyOjE3LCBMaW51cyBUb3J2YWxkcw0KPiA8dG9ydmFs ZHNAbGludXgtZm91bmRhdGlvbi5vcmc+IHdyb3RlOg0KPiA+DQo+ID4gTk9URSEgVGhpcyBpcyBv YnZpb3VzbHkgdW50ZXN0ZWQgYW5kIEkgZGlkbid0IGNoZWNrIHRoYXQgaXQgZG9lcyB0aGUNCj4g PiBjbXAvc2JiL29yIHRoZSByaWdodCB3YXkgYXJvdW5kLg0KPiANCj4gV2VsbCwgaXQgYm9vdHMu IFRoZSBjb2RlIGdlbmVyYXRpb24gKGZyb20gc3RybmNweV9mcm9tX3VzZXIoKSkgc2VlbXMgb2s6 DQo+IA0KPiAgICAgICBtb3ZhYnMgJDB4MTIzNDU2Nzg5YWJjZGVmLCVyY3gNCj4gICAgICAgY21w ICAgICVyc2ksJXJjeA0KPiAgICAgICBzYmIgICAgJWVjeCwlZWN4DQo+ICAgICAgIG9yICAgICAl cnNpLCVyY3gNCj4gDQo+IHdoZXJlIG9idmlvdXNseSB0aGF0IGNvbnN0YW50IGlzIHRoZSBib2d1 cyBwcmUtaW5pdGlhbGl6ZWQgdmFsdWUsIG5vdA0KPiB0aGUgYWN0dWFsIHJ1bnRpbWUgdmFsdWUu DQoNCldvdWxkIGl0IGJlIGJldHRlciB0byBtYWtlIHRoZSAnYm9ndXMnIGNvbnN0YW50IG9uZSB0 aGF0IG1ha2VzDQphbGwgYWNjZXNzZXMgZmFpbD8NClNvIHlvdSBzb29uIGZpbmQgb3V0IGl0IGFu eSBjb2RlIGRvZXNuJ3QgZ2V0IHBhdGNoZWQuDQoNCkkgYWxzbyB3b25kZXIgaG93IGJpZyB0aGUg dGFibGUgb2YgYWRkcmVzc2VzIHRvIHBhdGNoIGlzLg0KSWYgdGhhdCBnZXRzIGludG8gaW5saW5l ZCBmdW5jdGlvbnMgaXQgY291bGQgYmUgYmlnLg0KDQpPVE9IIGhhdmluZyBhIHJlYWwgZnVuY3Rp b24gdGhhdCBkb2VzIGFjY2Vzc19vaygpLCBjbGFjIGFuZCBhZGRyZXNzDQptYXNraW5nIG1heSBu b3QgcHJvYmxlbS4NCg0KRXNwZWNpYWxseSBpZiB0aGVyZSBpcyBhbHdheXMgYSAoUEFHRSBzaXpl ZCkgZ2FwIGJldHdlZW4gdGhlIGhpZ2hlc3QNCnVzZXIgYWRkcmVzcyBhbmQgdGhlIGxvd2VzdCBr ZXJuZWwgYWRkcmVzcyBzbyB0aGUgJ3NpemUnIGFyZ3VtZW50DQp0byBhY2Nlc3Nfb2soKSBjYW4g YmUgaWdub3JlZCBvbiB0aGUgYXNzdW1wdGlvbiB0aGF0IHRoZSBhY2Nlc3Nlcw0KYXJlIChyZWFz b25hYmx5KSBsaW5lYXIuDQoNCglEYXZpZA0KDQotDQpSZWdpc3RlcmVkIEFkZHJlc3MgTGFrZXNp ZGUsIEJyYW1sZXkgUm9hZCwgTW91bnQgRmFybSwgTWlsdG9uIEtleW5lcywgTUsxIDFQVCwgVUsN ClJlZ2lzdHJhdGlvbiBObzogMTM5NzM4NiAoV2FsZXMpDQo=