Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932235AbbFIM4H (ORCPT ); Tue, 9 Jun 2015 08:56:07 -0400 Received: from casper.infradead.org ([85.118.1.10]:50631 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752566AbbFIMz5 (ORCPT ); Tue, 9 Jun 2015 08:55:57 -0400 Message-ID: <1433854550.19447.15.camel@infradead.org> Subject: Re: [PATCH v11 0/10] iommu/vt-d: Fix intel vt-d faults in kdump kernel From: David Woodhouse To: Joerg Roedel Cc: bhe@redhat.com, tom.vaden@hp.com, rwright@hp.com, linux-pci@vger.kernel.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, lisa.mitchell@hp.com, iommu@lists.linux-foundation.org, "Li, Zhen-Hua" , doug.hatch@hp.com, ishii.hironobu@jp.fujitsu.com, bhelgaas@google.com, billsumnerlinux@gmail.com, li.zhang6@hp.com, dyoung@redhat.com, vgoyal@redhat.com Date: Tue, 09 Jun 2015 13:55:50 +0100 In-Reply-To: <20150608161315.GX20384@8bytes.org> References: <1431337974-545-1-git-send-email-zhen-hual@hp.com> <1433773583.2952.52.camel@infradead.org> <20150608152957.GW20384@8bytes.org> <1433778624.2952.82.camel@infradead.org> <20150608161315.GX20384@8bytes.org> Content-Type: multipart/signed; micalg="sha-1"; protocol="application/x-pkcs7-signature"; boundary="=-O7gUsVQfpaB+xjuFjS+j" X-Mailer: Evolution 3.16.2.1 (3.16.2.1-2.fc22) Mime-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 10185 Lines: 160 --=-O7gUsVQfpaB+xjuFjS+j Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Mon, 2015-06-08 at 18:13 +0200, Joerg Roedel wrote: > On Mon, Jun 08, 2015 at 04:50:24PM +0100, David Woodhouse wrote: > > On Mon, 2015-06-08 at 17:29 +0200, Joerg Roedel wrote: > > > Hmm, I also limited this functionality to kdump kernels. Do we still > > > need to preserve these extended data structures even when there is no > > > upstream support for them yet? > >=20 > > We *do* have upstream support. The 4.1 kernel will use the extended > > root/context tables and will set the DMA_RTADDR_RTT bit in the Root > > Table Address register, even though it doesn't yet actually *use* any > > of the shiny new bits in the extended context tables. > >=20 > > So the code which copies the context tables needs to take that into > > account. >=20 > Right, I missed that until now. So what the code with my changes does > is, it sets the DMA_RTADDR_RTT bit as it would do on a normal boot. But > unlike the root entry table address, this bit can not be changed while > translation is active. >=20 > So I think we need to read out that bit when we find translation enabled > and if it is different from what we would set it to, we bail out of any > copying, disable translation and proceed as in a normal boot. Given that this is only for kdump and not the general case of kexec, that's probably tolerable. Of course we do still need to make it *not* broken for the case where DMA_RTADDR_RTT is set, as it is at the moment. And I suspect if we're doing that, it might be simple enough to make it convert to/from the extended page tables. I don't think we want to preserve PASID tables; only the "second level" (i.e. traditional) translation. So we could happily pull the page table pointer out of either kind of context entry, and install it into either kind. I think there's a simple mapping of translation types too. I need to sort out the translation types when adding the real PASID support (imminently!) anyway. --=20 dwmw2 --=-O7gUsVQfpaB+xjuFjS+j Content-Type: application/x-pkcs7-signature; name="smime.p7s" Content-Disposition: attachment; filename="smime.p7s" Content-Transfer-Encoding: base64 MIAGCSqGSIb3DQEHAqCAMIACAQExCzAJBgUrDgMCGgUAMIAGCSqGSIb3DQEHAQAAoIISjjCCBicw ggUPoAMCAQICAw3vNzANBgkqhkiG9w0BAQUFADCBjDELMAkGA1UEBhMCSUwxFjAUBgNVBAoTDVN0 YXJ0Q29tIEx0ZC4xKzApBgNVBAsTIlNlY3VyZSBEaWdpdGFsIENlcnRpZmljYXRlIFNpZ25pbmcx ODA2BgNVBAMTL1N0YXJ0Q29tIENsYXNzIDEgUHJpbWFyeSBJbnRlcm1lZGlhdGUgQ2xpZW50IENB MB4XDTE1MDUwNTA5NDM0MVoXDTE2MDUwNTA5NTMzNlowQjEcMBoGA1UEAwwTZHdtdzJAaW5mcmFk ZWFkLm9yZzEiMCAGCSqGSIb3DQEJARYTZHdtdzJAaW5mcmFkZWFkLm9yZzCCASIwDQYJKoZIhvcN AQEBBQADggEPADCCAQoCggEBAMkbm9kPbx1j/X4RVyf/pPKSYwelcco69TvnQQbKM8m8xkWjXJI1 jpJ1jMaGUZGFToINMSZi7lZawUozudWbXSKy1SikENSTJHffsdRAIlsp+hR8vWvjsKUry6sEdqPG doa5RY7+N4WRusWZDYW/RRWE6i9EL9qV86CVPYqw22UBOUw4/j/HVGCV6TSB8yE5iEwhk/hUuzRr FZm1MJMR7mCS7BCR8Lr5jFY61lWpBiXNXIxLZCvDc26KR5L5tYX43iUVO3fzES1GRVoYnxxk2tmz fcsZG5vK+Trc9L8OZJfkYrEHH3+Iw41MQ0w/djVtYr1+HYldx0QmYXAtnhIj+UMCAwEAAaOCAtkw ggLVMAkGA1UdEwQCMAAwCwYDVR0PBAQDAgSwMB0GA1UdJQQWMBQGCCsGAQUFBwMCBggrBgEFBQcD BDAdBgNVHQ4EFgQUszC96C3w5/2+d+atSr0IpT26YI4wHwYDVR0jBBgwFoAUU3Ltkpzg2ssBXHx+ ljVO8tS4UYIwHgYDVR0RBBcwFYETZHdtdzJAaW5mcmFkZWFkLm9yZzCCAUwGA1UdIASCAUMwggE/ MIIBOwYLKwYBBAGBtTcBAgMwggEqMC4GCCsGAQUFBwIBFiJodHRwOi8vd3d3LnN0YXJ0c3NsLmNv bS9wb2xpY3kucGRmMIH3BggrBgEFBQcCAjCB6jAnFiBTdGFydENvbSBDZXJ0aWZpY2F0aW9uIEF1 dGhvcml0eTADAgEBGoG+VGhpcyBjZXJ0aWZpY2F0ZSB3YXMgaXNzdWVkIGFjY29yZGluZyB0byB0 aGUgQ2xhc3MgMSBWYWxpZGF0aW9uIHJlcXVpcmVtZW50cyBvZiB0aGUgU3RhcnRDb20gQ0EgcG9s aWN5LCByZWxpYW5jZSBvbmx5IGZvciB0aGUgaW50ZW5kZWQgcHVycG9zZSBpbiBjb21wbGlhbmNl IG9mIHRoZSByZWx5aW5nIHBhcnR5IG9ibGlnYXRpb25zLjA2BgNVHR8ELzAtMCugKaAnhiVodHRw Oi8vY3JsLnN0YXJ0c3NsLmNvbS9jcnR1MS1jcmwuY3JsMIGOBggrBgEFBQcBAQSBgTB/MDkGCCsG AQUFBzABhi1odHRwOi8vb2NzcC5zdGFydHNzbC5jb20vc3ViL2NsYXNzMS9jbGllbnQvY2EwQgYI KwYBBQUHMAKGNmh0dHA6Ly9haWEuc3RhcnRzc2wuY29tL2NlcnRzL3N1Yi5jbGFzczEuY2xpZW50 LmNhLmNydDAjBgNVHRIEHDAahhhodHRwOi8vd3d3LnN0YXJ0c3NsLmNvbS8wDQYJKoZIhvcNAQEF BQADggEBAHMQmxHHodpS85X8HRyxhvfkys7r+taCNOaNU9cxQu/cZ/6k5nS2qGNMzZ6jb7ueY/V7 7p+4DW/9ZWODDTf4Fz00mh5SSVc20Bz7t+hhxwHd62PZgENh5i76Qq2tw48U8AsYo5damHby1epf neZafLpUkLLO7AGBJIiRVTevdvyXQ0qnixOmKMWyvrhSNGuVIKVdeqLP+102Dwf+dpFyw+j1hz28 jEEKpHa+NR1b2kXuSPi/rMGhexwlJOh4tK8KQ6Ryr0rIN//NSbOgbyYZrzc/ZUWX9V5OA84ChFb2 vkFl0OcYrttp/rhDBLITwffPxSZeoBh9H7zYzkbCXKL3BUIwggYnMIIFD6ADAgECAgMN7zcwDQYJ KoZIhvcNAQEFBQAwgYwxCzAJBgNVBAYTAklMMRYwFAYDVQQKEw1TdGFydENvbSBMdGQuMSswKQYD VQQLEyJTZWN1cmUgRGlnaXRhbCBDZXJ0aWZpY2F0ZSBTaWduaW5nMTgwNgYDVQQDEy9TdGFydENv bSBDbGFzcyAxIFByaW1hcnkgSW50ZXJtZWRpYXRlIENsaWVudCBDQTAeFw0xNTA1MDUwOTQzNDFa Fw0xNjA1MDUwOTUzMzZaMEIxHDAaBgNVBAMME2R3bXcyQGluZnJhZGVhZC5vcmcxIjAgBgkqhkiG 9w0BCQEWE2R3bXcyQGluZnJhZGVhZC5vcmcwggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEKAoIB AQDJG5vZD28dY/1+EVcn/6TykmMHpXHKOvU750EGyjPJvMZFo1ySNY6SdYzGhlGRhU6CDTEmYu5W WsFKM7nVm10istUopBDUkyR337HUQCJbKfoUfL1r47ClK8urBHajxnaGuUWO/jeFkbrFmQ2Fv0UV hOovRC/alfOglT2KsNtlATlMOP4/x1Rglek0gfMhOYhMIZP4VLs0axWZtTCTEe5gkuwQkfC6+YxW OtZVqQYlzVyMS2Qrw3NuikeS+bWF+N4lFTt38xEtRkVaGJ8cZNrZs33LGRubyvk63PS/DmSX5GKx Bx9/iMONTENMP3Y1bWK9fh2JXcdEJmFwLZ4SI/lDAgMBAAGjggLZMIIC1TAJBgNVHRMEAjAAMAsG A1UdDwQEAwIEsDAdBgNVHSUEFjAUBggrBgEFBQcDAgYIKwYBBQUHAwQwHQYDVR0OBBYEFLMwvegt 8Of9vnfmrUq9CKU9umCOMB8GA1UdIwQYMBaAFFNy7ZKc4NrLAVx8fpY1TvLUuFGCMB4GA1UdEQQX MBWBE2R3bXcyQGluZnJhZGVhZC5vcmcwggFMBgNVHSAEggFDMIIBPzCCATsGCysGAQQBgbU3AQID MIIBKjAuBggrBgEFBQcCARYiaHR0cDovL3d3dy5zdGFydHNzbC5jb20vcG9saWN5LnBkZjCB9wYI KwYBBQUHAgIwgeowJxYgU3RhcnRDb20gQ2VydGlmaWNhdGlvbiBBdXRob3JpdHkwAwIBARqBvlRo aXMgY2VydGlmaWNhdGUgd2FzIGlzc3VlZCBhY2NvcmRpbmcgdG8gdGhlIENsYXNzIDEgVmFsaWRh dGlvbiByZXF1aXJlbWVudHMgb2YgdGhlIFN0YXJ0Q29tIENBIHBvbGljeSwgcmVsaWFuY2Ugb25s eSBmb3IgdGhlIGludGVuZGVkIHB1cnBvc2UgaW4gY29tcGxpYW5jZSBvZiB0aGUgcmVseWluZyBw YXJ0eSBvYmxpZ2F0aW9ucy4wNgYDVR0fBC8wLTAroCmgJ4YlaHR0cDovL2NybC5zdGFydHNzbC5j b20vY3J0dTEtY3JsLmNybDCBjgYIKwYBBQUHAQEEgYEwfzA5BggrBgEFBQcwAYYtaHR0cDovL29j c3Auc3RhcnRzc2wuY29tL3N1Yi9jbGFzczEvY2xpZW50L2NhMEIGCCsGAQUFBzAChjZodHRwOi8v YWlhLnN0YXJ0c3NsLmNvbS9jZXJ0cy9zdWIuY2xhc3MxLmNsaWVudC5jYS5jcnQwIwYDVR0SBBww GoYYaHR0cDovL3d3dy5zdGFydHNzbC5jb20vMA0GCSqGSIb3DQEBBQUAA4IBAQBzEJsRx6HaUvOV /B0csYb35MrO6/rWgjTmjVPXMULv3Gf+pOZ0tqhjTM2eo2+7nmP1e+6fuA1v/WVjgw03+Bc9NJoe UklXNtAc+7foYccB3etj2YBDYeYu+kKtrcOPFPALGKOXWph28tXqX53mWny6VJCyzuwBgSSIkVU3 r3b8l0NKp4sTpijFsr64UjRrlSClXXqiz/tdNg8H/naRcsPo9Yc9vIxBCqR2vjUdW9pF7kj4v6zB oXscJSToeLSvCkOkcq9KyDf/zUmzoG8mGa83P2VFl/VeTgPOAoRW9r5BZdDnGK7baf64QwSyE8H3 z8UmXqAYfR+82M5Gwlyi9wVCMIIGNDCCBBygAwIBAgIBHjANBgkqhkiG9w0BAQUFADB9MQswCQYD VQQGEwJJTDEWMBQGA1UEChMNU3RhcnRDb20gTHRkLjErMCkGA1UECxMiU2VjdXJlIERpZ2l0YWwg Q2VydGlmaWNhdGUgU2lnbmluZzEpMCcGA1UEAxMgU3RhcnRDb20gQ2VydGlmaWNhdGlvbiBBdXRo b3JpdHkwHhcNMDcxMDI0MjEwMTU1WhcNMTcxMDI0MjEwMTU1WjCBjDELMAkGA1UEBhMCSUwxFjAU BgNVBAoTDVN0YXJ0Q29tIEx0ZC4xKzApBgNVBAsTIlNlY3VyZSBEaWdpdGFsIENlcnRpZmljYXRl IFNpZ25pbmcxODA2BgNVBAMTL1N0YXJ0Q29tIENsYXNzIDEgUHJpbWFyeSBJbnRlcm1lZGlhdGUg Q2xpZW50IENBMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAxwmDzM4t2BqxKaQuE6uW vooyg4ymiEGWVUet1G8SD+rqvyNH4QrvnEIaFHxOhESip7vMz39ScLpNLbL1QpOlPW/tFIzNHS3q d2XRNYG5Sv9RcGE+T4qbLtsjjJbi6sL7Ls/f/X9ftTyhxvxWkf8KW37iKrueKsxw2HqolH7GM6FX 5UfNAwAu4ZifkpmZzU1slBhyWwaQPEPPZRsWoTb7q8hmgv6Nv3Hg9rmA1/VPBIOQ6SKRkHXG0Hhm q1dOFoAFI411+a/9nWm5rcVjGcIWZ2v/43Yksq60jExipA4l5uv9/+Hm33mbgmCszdj/Dthf13tg Av2O83hLJ0exTqfrlwIDAQABo4IBrTCCAakwDwYDVR0TAQH/BAUwAwEB/zAOBgNVHQ8BAf8EBAMC AQYwHQYDVR0OBBYEFFNy7ZKc4NrLAVx8fpY1TvLUuFGCMB8GA1UdIwQYMBaAFE4L7xqkQFulF2mH MMo0aEPQQa7yMGYGCCsGAQUFBwEBBFowWDAnBggrBgEFBQcwAYYbaHR0cDovL29jc3Auc3RhcnRz c2wuY29tL2NhMC0GCCsGAQUFBzAChiFodHRwOi8vd3d3LnN0YXJ0c3NsLmNvbS9zZnNjYS5jcnQw WwYDVR0fBFQwUjAnoCWgI4YhaHR0cDovL3d3dy5zdGFydHNzbC5jb20vc2ZzY2EuY3JsMCegJaAj hiFodHRwOi8vY3JsLnN0YXJ0c3NsLmNvbS9zZnNjYS5jcmwwgYAGA1UdIAR5MHcwdQYLKwYBBAGB tTcBAgEwZjAuBggrBgEFBQcCARYiaHR0cDovL3d3dy5zdGFydHNzbC5jb20vcG9saWN5LnBkZjA0 BggrBgEFBQcCARYoaHR0cDovL3d3dy5zdGFydHNzbC5jb20vaW50ZXJtZWRpYXRlLnBkZjANBgkq hkiG9w0BAQUFAAOCAgEACoMIfXirLAZcuGOMXq4cuSN3TaFx2H2GvD5VSy/6rV55BYHbWNaPeQn3 oBSU8KgQZn/Kck1JxbLpAxVCNtsxeW1R87ifhsYZ0qjdrA9anrW2MAWCtosmAOT4OxK9QPoSjCMx M3HbkZCDJgnlE8jMopH21BbyAYr7b5EfGRQJNtgWcvqSXwKHnTutR08+Kkn0KAkXCzeQNLeA5LlY UzFyM7kPAp8pIRMQ+seHunmyG642S2+y/qHEdMuGIwpfz3eDF1PdctL04qYK/zu+Qg1Bw0RwgigV Zs/0c5HP2/e9DBHh7eSwtzYlk4AUr6yxLlcwSjOfOmKEQ/Q8tzh0IFiNu9IPuTGAPBn4CPxD0+Ru 8T2wg8/s43R/PT3kd1OEqOJUl7q+h+r6fpvU0Fzxd2tC8Ga6fDEPme+1Nbi+03pVjuZQKbGwKJ66 gEn06WqaxVZC+J8hh/jR0k9mST1iAZPNYulcNJ8tKmVtjYsv0L1TSm2+NwON58tO+pIVzu3DWwSE XSf+qkDavQam+QtEOZxLBXI++aMUEapSn+k3Lxm48ZCYfAWLb/Xj7F5JQMbZvCexglAbYR0kIHqW 5DnsYSdMD/IplJMojx0NBrxJ3fN9dvX2Y6BIXRsF1du4qESm4/3CKuyUV7p9DW3mPlHTGLvYxnyK Qy7VFBkoLINszBrOUeIxggNvMIIDawIBATCBlDCBjDELMAkGA1UEBhMCSUwxFjAUBgNVBAoTDVN0 YXJ0Q29tIEx0ZC4xKzApBgNVBAsTIlNlY3VyZSBEaWdpdGFsIENlcnRpZmljYXRlIFNpZ25pbmcx ODA2BgNVBAMTL1N0YXJ0Q29tIENsYXNzIDEgUHJpbWFyeSBJbnRlcm1lZGlhdGUgQ2xpZW50IENB AgMN7zcwCQYFKw4DAhoFAKCCAa8wGAYJKoZIhvcNAQkDMQsGCSqGSIb3DQEHATAcBgkqhkiG9w0B CQUxDxcNMTUwNjA5MTI1NTUwWjAjBgkqhkiG9w0BCQQxFgQUeZ9cnPHhHD8x4DABMzCyy+6kJVQw gaUGCSsGAQQBgjcQBDGBlzCBlDCBjDELMAkGA1UEBhMCSUwxFjAUBgNVBAoTDVN0YXJ0Q29tIEx0 ZC4xKzApBgNVBAsTIlNlY3VyZSBEaWdpdGFsIENlcnRpZmljYXRlIFNpZ25pbmcxODA2BgNVBAMT L1N0YXJ0Q29tIENsYXNzIDEgUHJpbWFyeSBJbnRlcm1lZGlhdGUgQ2xpZW50IENBAgMN7zcwgacG CyqGSIb3DQEJEAILMYGXoIGUMIGMMQswCQYDVQQGEwJJTDEWMBQGA1UEChMNU3RhcnRDb20gTHRk LjErMCkGA1UECxMiU2VjdXJlIERpZ2l0YWwgQ2VydGlmaWNhdGUgU2lnbmluZzE4MDYGA1UEAxMv U3RhcnRDb20gQ2xhc3MgMSBQcmltYXJ5IEludGVybWVkaWF0ZSBDbGllbnQgQ0ECAw3vNzANBgkq hkiG9w0BAQEFAASCAQAbILlIo7cbOjG5lGUTz+B222+uqrXZNAJcg7wr+qhwpl472PZoZTIXM4Fu fmHuf8fN3vWybseYAQHG6NyQ1NxWDybOi9if+VxXM9TgBsQN5Dawn1Zr1+321KOl5Waze7bhqmTA +lSdXnJxa3j1lgopl1B+OuHKTOEadSSnTQ9QcCrxv7IPWeiW24GF9VCpA+UJzLKFGTZQa0W8hww2 5HgswK981sEl1gW762Gb0XyUNczyHqtyOdUMdTsS86LGO3qYxBhs1KKNe6aAiOmVzxJz82yoewgr ZkEQkN75Yr/qHs7pZTDdqJWWWv57cJg6xpkZ48SVcJ6d4fFOQpCssZ44AAAAAAAA --=-O7gUsVQfpaB+xjuFjS+j-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/