From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: ACJfBotexgevHYCSvNbRnIESs5ZDoL65OQypnXWs4IVaCW70QwZV0jsTV1UPiey5hLU0wGtafb2+ ARC-Seal: i=1; a=rsa-sha256; t=1515672633; cv=none; d=google.com; s=arc-20160816; b=MN9i23saMh6rpV2h91EdkF9NqOn3apfppx4tpW9b0FuEFVBYR+OptKHjE+AoxetwzB +AcYY/XjG6cgd4CZC5dUMkV1ul87TBWoCAeC9kfehTzXcekp6BIs9EhgRD2dXWprLMJs QS7kcpGhKQ3Qkd/Wb7Yw3roYg/Z1Mk9hHqao/85IU2/p3k+cAt35XYI5VrnbhsKO3yqf 1g4P3myhIB5D0KqQqvQnDknvvJ4GCOn4QA+1kxctU3ZZOkmk/XrnpcEP4Wa758Vs0x7G KjImpLPY2UGv1SCeZvEyOQViefT9E11GQYTISLJy2cV4goWkoAAVouHA0YurYCvNloFH ZkwQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:accept-language:in-reply-to:references:message-id:date :thread-index:thread-topic:subject:cc:to:from:mime-version :dkim-signature:arc-authentication-results; bh=o6FEMmMa5Hy9zEIwbqyFCUUcFY4YsAK57Psh5wQlQOg=; b=TXCZFxgLg8In1JcOUMwPGB+om1tUveusIVEhSm+bJk9GNo3q55rQRGfWXqiQx3sZle oGn0IF8/fIPD59lcADo+DlqZJQZ6CJpTsGcMQrELBGjeFserB/vMfgEXqYhpNlhfLMVv qtTe/90WnYQEI/aDwQHFN1TPp/V/1cynOZTUzPb3GkHKklIrWTGf8TsTDoun9HzG6+x9 xgz14hbvOvIYpu2JZQGNZVPhD69hAM5x444kEp+b0X/d08PQuIwyS334qzveKSiNCE7Z JrhtZusV0UDoy4Xa/VMbdKFUS0cV8rVO9jC2U7WTq7NOqogTVL6xBggaQiQkz2XfMVxj WpPA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@amazon.co.uk header.s=amazon201209 header.b=UfuFbMxI; spf=pass (google.com: domain of prvs=5423dbf64=dwmw@amazon.co.uk designates 52.95.49.90 as permitted sender) smtp.mailfrom=prvs=5423dbf64=dwmw@amazon.co.uk; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=amazon.co.uk Authentication-Results: mx.google.com; dkim=pass header.i=@amazon.co.uk header.s=amazon201209 header.b=UfuFbMxI; spf=pass (google.com: domain of prvs=5423dbf64=dwmw@amazon.co.uk designates 52.95.49.90 as permitted sender) smtp.mailfrom=prvs=5423dbf64=dwmw@amazon.co.uk; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=amazon.co.uk X-Amazon-filename: smime.p7s X-IronPort-AV: E=Sophos;i="5.46,344,1511827200"; d="p7s'?scan'208";a="326552073" Content-Type: multipart/mixed; boundary="===============2701122683662935080==" MIME-Version: 1.0 From: "Woodhouse, David" To: "peterz@infradead.org" CC: "linux-kernel@vger.kernel.org" , "tim.c.chen@linux.intel.com" , "torvalds@linux-foundation.org" , "tglx@linutronix.de" , "ak@linux.intel.com" , "x86@kernel.org" , "riel@redhat.com" , "keescook@google.com" , "gnomes@lxorguk.ukuu.org.uk" , "pjt@google.com" , "Ghitulete, Razvan-alin" , "bp@alien8.de" , "dave.hansen@intel.com" , "luto@amacapital.net" , "jikos@kernel.org" , "gregkh@linux-foundation.org" Subject: Re: [PATCH] x86/retpoline: Fill return stack buffer on vmexit Thread-Topic: [PATCH] x86/retpoline: Fill return stack buffer on vmexit Thread-Index: AQHTirkPo0Bk+T0+J0mlA41exrTL56NulNeA Date: Thu, 11 Jan 2018 12:10:18 +0000 Message-ID: <1515672617.22302.326.camel@amazon.co.uk> References: <1515624682-3556-1-git-send-email-dwmw@amazon.co.uk> <20180111084915.GU6176@hirez.programming.kicks-ass.net> In-Reply-To: <20180111084915.GU6176@hirez.programming.kicks-ass.net> Accept-Language: en-GB, en-US X-MS-Has-Attach: yes X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.43.62.4] MIME-Version: 1.0 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1589247701167723388?= X-GMAIL-MSGID: =?utf-8?q?1589297946663811339?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: --===============2701122683662935080== Content-Language: en-US Content-Type: multipart/signed; micalg=sha-256; protocol="application/x-pkcs7-signature"; boundary="=-mFuKfHPMW6QPIx+stMim" --=-mFuKfHPMW6QPIx+stMim Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Thu, 2018-01-11 at 09:49 +0100, Peter Zijlstra wrote: > On Wed, Jan 10, 2018 at 10:51:22PM +0000, David Woodhouse wrote: > >=20 > > This implements the most pressing of the RSB stuffing documented > > by dhansen (based our discussions) in https://goo.gl/pXbvBE > > Only took me 3 readings to find interrupts/traps were in fact > enumerated. Could we plretty please separate them from the deep call > case? Also might make sense to explicitly mention SMI, as that will be > the most difficult to fix :-( What part of "fuck Skylake" was difficult to understand? Seriously, use IBRS on Skylake, or accept that there are (relatively small?) holes ;) --=-mFuKfHPMW6QPIx+stMim Content-Type: application/x-pkcs7-signature; name="smime.p7s" Content-Disposition: attachment; filename="smime.p7s" Content-Transfer-Encoding: base64 MIAGCSqGSIb3DQEHAqCAMIACAQExDzANBglghkgBZQMEAgEFADCABgkqhkiG9w0BBwEAAKCCEE4w ggUuMIIEFqADAgECAhEApEtL31g6H7ROXdOiQnA9RjANBgkqhkiG9w0BAQsFADCBlzELMAkGA1UE BhMCR0IxGzAZBgNVBAgTEkdyZWF0ZXIgTWFuY2hlc3RlcjEQMA4GA1UEBxMHU2FsZm9yZDEaMBgG A1UEChMRQ09NT0RPIENBIExpbWl0ZWQxPTA7BgNVBAMTNENPTU9ETyBSU0EgQ2xpZW50IEF1dGhl bnRpY2F0aW9uIGFuZCBTZWN1cmUgRW1haWwgQ0EwHhcNMTcxMjIxMDAwMDAwWhcNMTgxMjIxMjM1 OTU5WjAiMSAwHgYJKoZIhvcNAQkBFhFkd213QGFtYXpvbi5jby51azCCASIwDQYJKoZIhvcNAQEB BQADggEPADCCAQoCggEBAKdGKgXuwKMg2r+i/4BZZC0ddRxNq3xIKTakie/VCSzoO7P17A36ZzUc VMEYPfqDt/65xoc6Tdih+qkY2pNDppZ1DZ8mVrAX6O2O60ZhmXB60wMoDvXPZInvkMOW4drqnje/ 7/NOypn/XQAY+ln4KT+3tHG3TfryyJFMedqC/r29KJlCeeCxIzdtq2j5mN42tvPVv4+p+Kr77uui 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