From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B2488C4727E for ; Wed, 7 Oct 2020 18:01:58 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8DECD2168B for ; Wed, 7 Oct 2020 18:01:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="XlsYCfTV" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8DECD2168B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ffwll.ch Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 789786E916; Wed, 7 Oct 2020 18:01:55 +0000 (UTC) Received: from mail-oo1-xc44.google.com (mail-oo1-xc44.google.com [IPv6:2607:f8b0:4864:20::c44]) by gabe.freedesktop.org (Postfix) with ESMTPS id 0F8A36E916 for ; Wed, 7 Oct 2020 18:01:54 +0000 (UTC) Received: by mail-oo1-xc44.google.com with SMTP id 4so835240ooh.11 for ; Wed, 07 Oct 2020 11:01:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=KjKZykFuT09vi8gvWSxWfIoih5+HtjIRxuS5MgzFTGo=; b=XlsYCfTVgW+6nmGAiv0O62GLPsC5r7eB+oidAEHNavDRGpWicEbtNZg9to7A5saHMp zaYRD/gT5inYX9JmqOP5ZzySgAIOp0+59TPao6y2kIbw9G7KU0mdvCuhCQrafShecj0J tHZf4mGHu3aegW49dmX0ZJptYBRUrRuO4MkvA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=KjKZykFuT09vi8gvWSxWfIoih5+HtjIRxuS5MgzFTGo=; b=EfHgqVw1LS2OpQ8Fnc7EoGvnrpEMkw8GHELbiVFNusF70/cnGRIeSC4+NgACwSH78R cqcfYAtiLyxmiQYtgVh0KldiKgSN1PF/gD9qN0ZKGfYbDiejXnvCsjBOCuD7S8K8HGrv Qb68SyUFi5CNkn1ZutuE50n0wRAn7ZaiAL8+JaizzANmBSXq/8lcNTd5i4ewKpI5UBXJ YGbOax4GlleOaf7EFuP6udN8StDkZp/RWb6VuTqjnnQcF1RDTJC0qbspFIHwb/Aafxhs t/ustXoLMGbNiN+tikdQS7JAr3gny+m/9yng2qiTDMTCY7hYguKtpNhOS0IZMet9eb8V OQZA== X-Gm-Message-State: AOAM530PXfvoHr918MzhI/hbNP6+zhfPcJkTT9trfkRyUIA/EwcWBLke 4L7iHYzo8gfewFJGl9FWhyT/5UN9oSGmO23IWo4afg== X-Google-Smtp-Source: ABdhPJwJzYY7PIFYfmYEAKc+uMwrEIxle3PFN75o5nMMKSdxenHBbi1fgd2mUNbWFOGRvdaIUhxGwTNij1DRYovGNtE= X-Received: by 2002:a4a:c011:: with SMTP id v17mr2806667oop.89.1602093713265; Wed, 07 Oct 2020 11:01:53 -0700 (PDT) MIME-Version: 1.0 References: <20201007164426.1812530-1-daniel.vetter@ffwll.ch> <20201007164426.1812530-8-daniel.vetter@ffwll.ch> <20201007172746.GU5177@ziepe.ca> In-Reply-To: <20201007172746.GU5177@ziepe.ca> From: Daniel Vetter Date: Wed, 7 Oct 2020 20:01:42 +0200 Message-ID: Subject: Re: [PATCH 07/13] mm: close race in generic_access_phys To: Jason Gunthorpe X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-s390@vger.kernel.org, Rik van Riel , linux-samsung-soc , Jan Kara , Kees Cook , kvm@vger.kernel.org, Dave Airlie , LKML , DRI Development , Linux MM , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , Daniel Vetter , John Hubbard , Hugh Dickins , Dan Williams , Andrew Morton , Linux ARM , "open list:DMA BUFFER SHARING FRAMEWORK" Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" T24gV2VkLCBPY3QgNywgMjAyMCBhdCA3OjI3IFBNIEphc29uIEd1bnRob3JwZSA8amdnQHppZXBl LmNhPiB3cm90ZToKPgo+IE9uIFdlZCwgT2N0IDA3LCAyMDIwIGF0IDA2OjQ0OjIwUE0gKzAyMDAs IERhbmllbCBWZXR0ZXIgd3JvdGU6Cj4gPiBXYXkgYmFjayBpdCB3YXMgYSByZWFzb25hYmxlIGFz c3VtcHRpb25zIHRoYXQgaW9tZW0gbWFwcGluZ3MgbmV2ZXIKPiA+IGNoYW5nZSB0aGUgcGZuIHJh bmdlIHRoZXkgcG9pbnQgYXQuIEJ1dCB0aGlzIGhhcyBjaGFuZ2VkOgo+ID4KPiA+IC0gZ3B1IGRy aXZlcnMgZHluYW1pY2FsbHkgbWFuYWdlIHRoZWlyIG1lbW9yeSBub3dhZGF5cywgaW52YWxpZGF0 aW5nCj4gPiAgIHB0ZXMgd2l0aCB1bm1hcF9tYXBwaW5nX3JhbmdlIHdoZW4gYnVmZmVycyBnZXQg bW92ZWQKPiA+Cj4gPiAtIGNvbnRpZ3VvdXMgZG1hIGFsbG9jYXRpb25zIGhhdmUgbW92ZWQgZnJv bSBkZWRpY2F0ZWQgY2FydmV0b3V0cyB0bwo+ID4gICBjbWEgcmVnaW9ucy4gVGhpcyBtZWFucyBp ZiB3ZSBtaXNzIHRoZSB1bm1hcCB0aGUgcGZuIG1pZ2h0IGNvbnRhaW4KPiA+ICAgcGFnZWNhY2hl IG9yIGFub24gbWVtb3J5ICh3ZWxsIGFueXRoaW5nIGFsbG9jYXRlZCB3aXRoIEdGUF9NT1ZFQUJM RSkKPiA+Cj4gPiAtIGV2ZW4gL2Rldi9tZW0gbm93IGludmFsaWRhdGVzIG1hcHBpbmdzIHdoZW4g dGhlIGtlcm5lbCByZXF1ZXN0cyB0aGF0Cj4gPiAgIGlvbWVtIHJlZ2lvbiB3aGVuIENPTkZJR19J T19TVFJJQ1RfREVWTUVNIGlzIHNldCwgc2VlIDMyMzRhYzY2NGE4Nwo+ID4gICAoIi9kZXYvbWVt OiBSZXZva2UgbWFwcGluZ3Mgd2hlbiBhIGRyaXZlciBjbGFpbXMgdGhlIHJlZ2lvbiIpCj4gPgo+ ID4gQWNjZXNzaW5nIHBmbnMgb2J0YWluZWQgZnJvbSBwdGVzIHdpdGhvdXQgaG9sZGluZyBhbGwg dGhlIGxvY2tzIGlzCj4gPiB0aGVyZWZvcmUgbm8gbG9uZ2VyIGEgZ29vZCBpZGVhLiBGaXggdGhp cy4KPiA+Cj4gPiBTaW5jZSBpb3JlbWFwIG1pZ2h0IG5lZWQgdG8gbWFuaXB1bGF0ZSBwYWdldGFi bGVzIHRvbyB3ZSBuZWVkIHRvIGRyb3AKPiA+IHRoZSBwdCBsb2NrIGFuZCBoYXZlIGEgcmV0cnkg bG9vcCBpZiB3ZSByYWNlZC4KPiA+Cj4gPiBXaGlsZSBhdCBpdCwgYWxzbyBhZGQga2VybmVsZG9j IGFuZCBpbXByb3ZlIHRoZSBjb21tZW50IGZvciB0aGUKPiA+IHZtYV9vcHMtPmFjY2VzcyBmdW5j dGlvbi4gSXQncyBmb3IgYWNjZXNzaW5nLCBub3QgZm9yIG1vdmluZyB0aGUKPiA+IG1lbW9yeSBm cm9tIGlvbWVtIHRvIHN5c3RlbSBtZW1vcnksIGFzIHRoZSBvbGQgY29tbWVudCBzZWVtZWQgdG8K PiA+IHN1Z2dlc3QuCj4gPgo+ID4gUmVmZXJlbmNlczogMjhiMmVlMjBjN2NiICgiYWNjZXNzX3By b2Nlc3Nfdm0gZGV2aWNlIG1lbW9yeSBpbmZyYXN0cnVjdHVyZSIpCj4gPiBDYzogSmFzb24gR3Vu dGhvcnBlIDxqZ2dAemllcGUuY2E+Cj4gPiBDYzogRGFuIFdpbGxpYW1zIDxkYW4uai53aWxsaWFt c0BpbnRlbC5jb20+Cj4gPiBDYzogS2VlcyBDb29rIDxrZWVzY29va0BjaHJvbWl1bS5vcmc+Cj4g PiBDYzogUmlrIHZhbiBSaWVsIDxyaWVsQHJlZGhhdC5jb20+Cj4gPiBDYzogQmVuamFtaW4gSGVy cmVuc21pZHQgPGJlbmhAa2VybmVsLmNyYXNoaW5nLm9yZz4KPiA+IENjOiBEYXZlIEFpcmxpZSA8 YWlybGllZEBsaW51eC5pZT4KPiA+IENjOiBIdWdoIERpY2tpbnMgPGh1Z2hAdmVyaXRhcy5jb20+ Cj4gPiBDYzogQW5kcmV3IE1vcnRvbiA8YWtwbUBsaW51eC1mb3VuZGF0aW9uLm9yZz4KPiA+IENj OiBKb2huIEh1YmJhcmQgPGpodWJiYXJkQG52aWRpYS5jb20+Cj4gPiBDYzogSsOpcsO0bWUgR2xp c3NlIDxqZ2xpc3NlQHJlZGhhdC5jb20+Cj4gPiBDYzogSmFuIEthcmEgPGphY2tAc3VzZS5jej4K PiA+IENjOiBEYW4gV2lsbGlhbXMgPGRhbi5qLndpbGxpYW1zQGludGVsLmNvbT4KPiA+IENjOiBs aW51eC1tbUBrdmFjay5vcmcKPiA+IENjOiBsaW51eC1hcm0ta2VybmVsQGxpc3RzLmluZnJhZGVh ZC5vcmcKPiA+IENjOiBsaW51eC1zYW1zdW5nLXNvY0B2Z2VyLmtlcm5lbC5vcmcKPiA+IENjOiBs aW51eC1tZWRpYUB2Z2VyLmtlcm5lbC5vcmcKPiA+IFNpZ25lZC1vZmYtYnk6IERhbmllbCBWZXR0 ZXIgPGRhbmllbC52ZXR0ZXJAaW50ZWwuY29tPgo+ID4gLS0tCj4gPiAgaW5jbHVkZS9saW51eC9t bS5oIHwgIDMgKystCj4gPiAgbW0vbWVtb3J5LmMgICAgICAgIHwgNDQgKysrKysrKysrKysrKysr KysrKysrKysrKysrKysrKysrKysrKysrKysrLS0KPiA+ICAyIGZpbGVzIGNoYW5nZWQsIDQ0IGlu c2VydGlvbnMoKyksIDMgZGVsZXRpb25zKC0pCj4KPiBUaGlzIGRvZXMgc2VlbSB0byBzb2x2ZSB0 aGUgcmFjZSB3aXRoIHJldm9rZV9kZXZtZW0oKSwgYnV0IGl0IGlzIHJlYWxseSB1Z2x5Lgo+Cj4g SXQgd291bGQgYmUgbXVjaCBuaWNlciB0byB3cmFwIGEgcndzZW0gYXJvdW5kIHRoaXMgYWNjZXNz IGFuZCB0aGUgdW5tYXAuCj4KPiBBbnkgcGxhY2UgdXNpbmcgaXQgaGFzIGEgbmljZSBsaW5lYXIg dHJhbnNsYXRpb24gZnJvbSB2bV9vZmYgdG8gcGZuLAo+IHNvIEkgZG9uJ3QgdGhpbmsgdGhlcmUg aXMgYSBzdWNoIGEgZ29vZCByZWFzb24gdG8gdXNlIGZvbGxvd19wdGUgaW4KPiB0aGUgZmlyc3Qg cGxhY2UuCj4KPiBpZSB3aHkgbm90IHRoZSBoZWxwZXIgYmUgdGhpczoKPgo+ICBpbnQgZ2VuZXJp Y19hY2Nlc3NfcGh5cyh1bnNpZ25lZCBsb25nIHBmbiwgdW5zaWduZWQgbG9uZyBwZ3Byb3QsCj4g ICAgICAgdm9pZCAqYnVmLCBzaXplX3QgbGVuLCBib29sIHdyaXRlKQo+Cj4gVGhlbiBzb21ldGhp bmcgbGlrZSBkZXYvbWVtIHdvdWxkIGNvbXB1dGUgcGZuIGFuZCBvYnRhaW4gdGhlIGxvY2s6Cj4K PiBkZXZfYWNjZXNzKHN0cnVjdCB2bV9hcmVhX3N0cnVjdCAqdm1hLCB1bnNpZ25lZCBsb25nIGFk ZHIsIHZvaWQgKmJ1ZiwgaW50IGxlbiwgaW50IHdyaXRlKQo+IHsKPiAgICAgIGNwdV9hZGRyID0g dm1hLT52bV9wZ29mZipQQUdFX1NJWkUgKyAoYWRkciAtIHZtYS0+dm1fc3RhcnQpKTsKPgo+ICAg ICAgLyogRklYTUU6IEhhcyB0byBiZSBvdmVyIGVhY2ggcGFnZSBvZiBsZW4gKi8KPiAgICAgIGlm ICghZGV2bWVtX2lzX2FsbG93ZWRfYWNjZXNzKFBIWVNfUEZOKGNwdV9hZGRyLzQwOTYpKSkKPiAg ICAgICAgICAgIHJldHVybiAtRVBFUk07Cj4KPiAgICAgIGRvd25fcmVhZCgmbWVtX3NlbSk7Cj4g ICAgICBnZW5lcmljX2FjY2Vzc19waHlzKGNwdV9hZGRyLzQwOTYsIHBncHJvdF92YWwodm1hLT52 bV9wYWdlX3Byb3QpLAo+ICAgICAgICAgICAgICAgICAgICAgICAgICBidWYsIGxlbiwgd3JpdGUp Owo+ICAgICAgdXBfcmVhZCgmbWVtX3NlbSk7Cj4gfQo+Cj4gVGhlIG90aGVyIGNhc2VzIGxvb2tl ZCBzaW1wbGVyIGJlY2F1c2UgdGhleSBkb24ndCByZXZva2UsIGhlcmUgdGhlCj4gbW1hcF9zZW0g YWxvbmUgc2hvdWxkIGJlIGVub3VnaCBwcm90ZWN0aW9uLCB0aGV5IHdvdWxkIGp1c3QgbmVlZCB0 bwo+IHByb3ZpZGUgdGhlIGxpbmVhciB0cmFuc2xhdGlvbiB0byBwZm4uCj4KPiBXaGF0IGRvIHlv dSB0aGluaz8KCkkgdGhpbmsgaXQnZCBmaXggdGhlIGJ1ZywgdW50aWwgc29tZW9uZSB3aXJlcyAt PmFjY2VzcyB1cCBmb3IKZHJpdmVycy9ncHUsIG9yIHRoZSBuZXh0IHN1YnN5c3RlbS4gVGhpcyBp cyBhbHNvIGp1c3QgZm9yIHB0cmFjZSwgc28Kd2UgcmVhbGx5IGRvbid0IGNhcmUgd2hlbiB3ZSBz dGFsbCB0aGUgdm0gYmFkbHkgYW5kIG90aGVyIHNpbGx5CnRoaW5ncy4gU28gSSBmaWd1cmVkIHRo ZSBzb21ld2hhdCB1Z2x5LCBidXQgZnVsbCBnZW5lcmljIHNvbHV0aW9uIGlzCnRoZSBiZXR0ZXIg b25lLCBzbyB0aGF0IHBlb3BsZSB3aG8gd2FudCB0byBiZSBhYmxlIHRvIHB0cmFjZQpyZWFkL3dy aXRlIHRoZWlyIGlvbWVtIG1tYXBzIGNhbiBqdXN0IHNwcmlua2xlIHRoaXMgd2hlcmV2ZXIgdGhl eSBmZWVsCmxpa2UuCgpCdXQgeWVhaCBpZiB3ZSBnbyB3aXRoIG1vc3QgbWluaW1hbCBmaXgsIGku ZS4gb25seSB0cnlpbmcgdG8gZml4IHRoZQpjdXJyZW50IHVzZXJzLCB0aGVuIHlvdXIgdGhpbmcg c2hvdWxkIHdvcmsgYW5kIGlzIHNpbXBsZXIuIEJ1dCBpdApsZWF2ZXMgdGhlIGRvb3Igb3BlbiBm b3IgZnV0dXJlIHByb2JsZW1zLgotRGFuaWVsCi0tIApEYW5pZWwgVmV0dGVyClNvZnR3YXJlIEVu Z2luZWVyLCBJbnRlbCBDb3Jwb3JhdGlvbgpodHRwOi8vYmxvZy5mZndsbC5jaApfX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fXwpkcmktZGV2ZWwgbWFpbGluZyBs aXN0CmRyaS1kZXZlbEBsaXN0cy5mcmVlZGVza3RvcC5vcmcKaHR0cHM6Ly9saXN0cy5mcmVlZGVz a3RvcC5vcmcvbWFpbG1hbi9saXN0aW5mby9kcmktZGV2ZWwK