From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755955AbbLQKJc (ORCPT ); Thu, 17 Dec 2015 05:09:32 -0500 Received: from smtp-out6.electric.net ([192.162.217.183]:50242 "EHLO smtp-out6.electric.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755332AbbLQKJ3 (ORCPT ); Thu, 17 Dec 2015 05:09:29 -0500 From: David Laight To: "'Alex Williamson'" , Yongji Xie , "kvm@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-api@vger.kernel.org" , "linuxppc-dev@lists.ozlabs.org" CC: "nikunj@linux.vnet.ibm.com" , "zhong@linux.vnet.ibm.com" , "aik@ozlabs.ru" , "paulus@samba.org" , "warrier@linux.vnet.ibm.com" Subject: RE: [RFC PATCH 3/3] vfio-pci: Allow to mmap MSI-X table if EEH is supported Thread-Topic: [RFC PATCH 3/3] vfio-pci: Allow to mmap MSI-X table if EEH is supported Thread-Index: AQHROD40DC0ohk0fwkq5PmT6EqV+OZ7O8Msg Date: Thu, 17 Dec 2015 10:08:04 +0000 Message-ID: <063D6719AE5E284EB5DD2968C1650D6D1CBEF1BC@AcuExch.aculab.com> References: <1449823994-3356-1-git-send-email-xyjxie@linux.vnet.ibm.com> <1449823994-3356-4-git-send-email-xyjxie@linux.vnet.ibm.com> <1450296869.2674.62.camel@redhat.com> In-Reply-To: <1450296869.2674.62.camel@redhat.com> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.202.99.200] Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 X-Outbound-IP: 213.249.233.130 X-Env-From: David.Laight@ACULAB.COM X-PolicySMART: 3396946, 3397078 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by mail.home.local id tBHA9cu0015211 > The MSI-X table is paravirtualized on vfio in general and interrupt > remapping theoretically protects against errant interrupts, so why is > this PPC64 specific? We have the same safeguards on x86 if we want to > decide they're sufficient. Offhand, the only way I can think that a > device can touch the MSI-X table is via backdoors or p2p DMA with > another device. Is this all related to the statements in the PCI(e) spec that the MSI-X table and Pending bit array should in their own BARs? (ISTR it even suggests a BAR each.) Since the MSI-X table exists in device memory/registers there is nothing to stop the device modifying the table contents (or even ignoring the contents and writing address+data pairs that are known to reference the CPUs MSI-X interrupt generation logic). We've an fpga based PCIe slave that has some additional PCIe slaves (associated with the interrupt generation logic) that are currently next to the PBA (which is 8k from the MSI-X table). If we can't map the PBA we can't actually raise any interrupts. The same would be true if page size is 64k and mapping the MSI-X table banned. Do we need to change our PCIe slave address map so we don't need to access anything in the same page (which might be 64k were we to target large ppc - which we don't at the moment) as both the MSI-X table and the PBA? I'd also note that being able to read the MSI-X table is a useful diagnostic that the relevant interrupts are enabled properly. David {.n++%ݶw{.n+{G{ayʇڙ,jfhz_(階ݢj"mG?&~iOzv^m ?I From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Laight Subject: RE: [RFC PATCH 3/3] vfio-pci: Allow to mmap MSI-X table if EEH is supported Date: Thu, 17 Dec 2015 10:08:04 +0000 Message-ID: <063D6719AE5E284EB5DD2968C1650D6D1CBEF1BC@AcuExch.aculab.com> References: <1449823994-3356-1-git-send-email-xyjxie@linux.vnet.ibm.com> <1449823994-3356-4-git-send-email-xyjxie@linux.vnet.ibm.com> <1450296869.2674.62.camel@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <1450296869.2674.62.camel@redhat.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: 'Alex Williamson' , Yongji Xie , "kvm@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-api@vger.kernel.org" , "linuxppc-dev@lists.ozlabs.org" Cc: "nikunj@linux.vnet.ibm.com" , "zhong@linux.vnet.ibm.com" , "aik@ozlabs.ru" , "paulus@samba.org" , "warrier@linux.vnet.ibm.com" List-Id: linux-api@vger.kernel.org PiBUaGUgTVNJLVggdGFibGUgaXMgcGFyYXZpcnR1YWxpemVkIG9uIHZmaW8gaW4gZ2VuZXJhbCBh bmQgaW50ZXJydXB0DQo+IHJlbWFwcGluZyB0aGVvcmV0aWNhbGx5IHByb3RlY3RzIGFnYWluc3Qg ZXJyYW50IGludGVycnVwdHMsIHNvIHdoeSBpcw0KPiB0aGlzIFBQQzY0IHNwZWNpZmljPyBXZSBo YXZlIHRoZSBzYW1lIHNhZmVndWFyZHMgb24geDg2IGlmIHdlIHdhbnQgdG8NCj4gZGVjaWRlIHRo ZXkncmUgc3VmZmljaWVudC4gT2ZmaGFuZCwgdGhlIG9ubHkgd2F5IEkgY2FuIHRoaW5rIHRoYXQg YQ0KPiBkZXZpY2UgY2FuIHRvdWNoIHRoZSBNU0ktWCB0YWJsZSBpcyB2aWEgYmFja2Rvb3JzIG9y IHAycCBETUEgd2l0aA0KPiBhbm90aGVyIGRldmljZS4NCg0KSXMgdGhpcyBhbGwgcmVsYXRlZCB0 byB0aGUgc3RhdGVtZW50cyBpbiB0aGUgUENJKGUpIHNwZWMgdGhhdCB0aGUNCk1TSS1YIHRhYmxl IGFuZCBQZW5kaW5nIGJpdCBhcnJheSBzaG91bGQgaW4gdGhlaXIgb3duIEJBUnM/DQooSVNUUiBp dCBldmVuIHN1Z2dlc3RzIGEgQkFSIGVhY2guKQ0KDQpTaW5jZSB0aGUgTVNJLVggdGFibGUgZXhp c3RzIGluIGRldmljZSBtZW1vcnkvcmVnaXN0ZXJzIHRoZXJlIGlzDQpub3RoaW5nIHRvIHN0b3Ag dGhlIGRldmljZSBtb2RpZnlpbmcgdGhlIHRhYmxlIGNvbnRlbnRzIChvciBldmVuDQppZ25vcmlu ZyB0aGUgY29udGVudHMgYW5kIHdyaXRpbmcgYWRkcmVzcytkYXRhIHBhaXJzIHRoYXQgYXJlIGtu b3duDQp0byByZWZlcmVuY2UgdGhlIENQVXMgTVNJLVggaW50ZXJydXB0IGdlbmVyYXRpb24gbG9n aWMpLg0KDQpXZSd2ZSBhbiBmcGdhIGJhc2VkIFBDSWUgc2xhdmUgdGhhdCBoYXMgc29tZSBhZGRp dGlvbmFsIFBDSWUgc2xhdmVzDQooYXNzb2NpYXRlZCB3aXRoIHRoZSBpbnRlcnJ1cHQgZ2VuZXJh dGlvbiBsb2dpYykgdGhhdCBhcmUgY3VycmVudGx5DQpuZXh0IHRvIHRoZSBQQkEgKHdoaWNoIGlz IDhrIGZyb20gdGhlIE1TSS1YIHRhYmxlKS4NCklmIHdlIGNhbid0IG1hcCB0aGUgUEJBIHdlIGNh bid0IGFjdHVhbGx5IHJhaXNlIGFueSBpbnRlcnJ1cHRzLg0KVGhlIHNhbWUgd291bGQgYmUgdHJ1 ZSBpZiBwYWdlIHNpemUgaXMgNjRrIGFuZCBtYXBwaW5nIHRoZSBNU0ktWA0KdGFibGUgYmFubmVk Lg0KDQpEbyB3ZSBuZWVkIHRvIGNoYW5nZSBvdXIgUENJZSBzbGF2ZSBhZGRyZXNzIG1hcCBzbyB3 ZSBkb24ndCBuZWVkDQp0byBhY2Nlc3MgYW55dGhpbmcgaW4gdGhlIHNhbWUgcGFnZSAod2hpY2gg bWlnaHQgYmUgNjRrIHdlcmUgd2UgdG8NCnRhcmdldCBsYXJnZSBwcGMgLSB3aGljaCB3ZSBkb24n dCBhdCB0aGUgbW9tZW50KSBhcyBib3RoIHRoZQ0KTVNJLVggdGFibGUgYW5kIHRoZSBQQkE/DQoN CkknZCBhbHNvIG5vdGUgdGhhdCBiZWluZyBhYmxlIHRvIHJlYWQgdGhlIE1TSS1YIHRhYmxlIGlz IGEgdXNlZnVsDQpkaWFnbm9zdGljIHRoYXQgdGhlIHJlbGV2YW50IGludGVycnVwdHMgYXJlIGVu YWJsZWQgcHJvcGVybHkuDQoNCglEYXZpZA0KDQo= From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp-out6.electric.net (smtp-out6.electric.net [192.162.217.184]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 986031A127D for ; Thu, 17 Dec 2015 21:09:30 +1100 (AEDT) From: David Laight To: 'Alex Williamson' , Yongji Xie , "kvm@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-api@vger.kernel.org" , "linuxppc-dev@lists.ozlabs.org" CC: "nikunj@linux.vnet.ibm.com" , "zhong@linux.vnet.ibm.com" , "aik@ozlabs.ru" , "paulus@samba.org" , "warrier@linux.vnet.ibm.com" Subject: RE: [RFC PATCH 3/3] vfio-pci: Allow to mmap MSI-X table if EEH is supported Date: Thu, 17 Dec 2015 10:08:04 +0000 Message-ID: <063D6719AE5E284EB5DD2968C1650D6D1CBEF1BC@AcuExch.aculab.com> References: <1449823994-3356-1-git-send-email-xyjxie@linux.vnet.ibm.com> <1449823994-3356-4-git-send-email-xyjxie@linux.vnet.ibm.com> <1450296869.2674.62.camel@redhat.com> In-Reply-To: <1450296869.2674.62.camel@redhat.com> Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , PiBUaGUgTVNJLVggdGFibGUgaXMgcGFyYXZpcnR1YWxpemVkIG9uIHZmaW8gaW4gZ2VuZXJhbCBh bmQgaW50ZXJydXB0DQo+IHJlbWFwcGluZyB0aGVvcmV0aWNhbGx5IHByb3RlY3RzIGFnYWluc3Qg ZXJyYW50IGludGVycnVwdHMsIHNvIHdoeSBpcw0KPiB0aGlzIFBQQzY0IHNwZWNpZmljPyBXZSBo YXZlIHRoZSBzYW1lIHNhZmVndWFyZHMgb24geDg2IGlmIHdlIHdhbnQgdG8NCj4gZGVjaWRlIHRo ZXkncmUgc3VmZmljaWVudC4gT2ZmaGFuZCwgdGhlIG9ubHkgd2F5IEkgY2FuIHRoaW5rIHRoYXQg YQ0KPiBkZXZpY2UgY2FuIHRvdWNoIHRoZSBNU0ktWCB0YWJsZSBpcyB2aWEgYmFja2Rvb3JzIG9y IHAycCBETUEgd2l0aA0KPiBhbm90aGVyIGRldmljZS4NCg0KSXMgdGhpcyBhbGwgcmVsYXRlZCB0 byB0aGUgc3RhdGVtZW50cyBpbiB0aGUgUENJKGUpIHNwZWMgdGhhdCB0aGUNCk1TSS1YIHRhYmxl IGFuZCBQZW5kaW5nIGJpdCBhcnJheSBzaG91bGQgaW4gdGhlaXIgb3duIEJBUnM/DQooSVNUUiBp dCBldmVuIHN1Z2dlc3RzIGEgQkFSIGVhY2guKQ0KDQpTaW5jZSB0aGUgTVNJLVggdGFibGUgZXhp c3RzIGluIGRldmljZSBtZW1vcnkvcmVnaXN0ZXJzIHRoZXJlIGlzDQpub3RoaW5nIHRvIHN0b3Ag dGhlIGRldmljZSBtb2RpZnlpbmcgdGhlIHRhYmxlIGNvbnRlbnRzIChvciBldmVuDQppZ25vcmlu ZyB0aGUgY29udGVudHMgYW5kIHdyaXRpbmcgYWRkcmVzcytkYXRhIHBhaXJzIHRoYXQgYXJlIGtu b3duDQp0byByZWZlcmVuY2UgdGhlIENQVXMgTVNJLVggaW50ZXJydXB0IGdlbmVyYXRpb24gbG9n aWMpLg0KDQpXZSd2ZSBhbiBmcGdhIGJhc2VkIFBDSWUgc2xhdmUgdGhhdCBoYXMgc29tZSBhZGRp dGlvbmFsIFBDSWUgc2xhdmVzDQooYXNzb2NpYXRlZCB3aXRoIHRoZSBpbnRlcnJ1cHQgZ2VuZXJh dGlvbiBsb2dpYykgdGhhdCBhcmUgY3VycmVudGx5DQpuZXh0IHRvIHRoZSBQQkEgKHdoaWNoIGlz IDhrIGZyb20gdGhlIE1TSS1YIHRhYmxlKS4NCklmIHdlIGNhbid0IG1hcCB0aGUgUEJBIHdlIGNh bid0IGFjdHVhbGx5IHJhaXNlIGFueSBpbnRlcnJ1cHRzLg0KVGhlIHNhbWUgd291bGQgYmUgdHJ1 ZSBpZiBwYWdlIHNpemUgaXMgNjRrIGFuZCBtYXBwaW5nIHRoZSBNU0ktWA0KdGFibGUgYmFubmVk Lg0KDQpEbyB3ZSBuZWVkIHRvIGNoYW5nZSBvdXIgUENJZSBzbGF2ZSBhZGRyZXNzIG1hcCBzbyB3 ZSBkb24ndCBuZWVkDQp0byBhY2Nlc3MgYW55dGhpbmcgaW4gdGhlIHNhbWUgcGFnZSAod2hpY2gg bWlnaHQgYmUgNjRrIHdlcmUgd2UgdG8NCnRhcmdldCBsYXJnZSBwcGMgLSB3aGljaCB3ZSBkb24n dCBhdCB0aGUgbW9tZW50KSBhcyBib3RoIHRoZQ0KTVNJLVggdGFibGUgYW5kIHRoZSBQQkE/DQoN CkknZCBhbHNvIG5vdGUgdGhhdCBiZWluZyBhYmxlIHRvIHJlYWQgdGhlIE1TSS1YIHRhYmxlIGlz IGEgdXNlZnVsDQpkaWFnbm9zdGljIHRoYXQgdGhlIHJlbGV2YW50IGludGVycnVwdHMgYXJlIGVu YWJsZWQgcHJvcGVybHkuDQoNCglEYXZpZA0KDQo=