From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lists.gentoo.org (pigeon.gentoo.org [208.92.234.80]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by finch.gentoo.org (Postfix) with ESMTPS id 2D74F1382C5 for ; Thu, 4 Jan 2018 03:34:09 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id C335CE087B; Thu, 4 Jan 2018 03:34:03 +0000 (UTC) Received: from mail-oi0-x230.google.com (mail-oi0-x230.google.com [IPv6:2607:f8b0:4003:c06::230]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by pigeon.gentoo.org (Postfix) with ESMTPS id 6766FE085E for ; Thu, 4 Jan 2018 03:34:03 +0000 (UTC) Received: by mail-oi0-x230.google.com with SMTP id r63so261177oia.6 for ; Wed, 03 Jan 2018 19:34:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to; bh=uJm3VDtQ7R8vz/+TAfm7B10woXZjkuStG2UVs7bOsPw=; b=aKLac9euo9ulqCvfuppFtjGmy6VjbqqzvFH4NqHjdjAsEkECeJdUDBo3PR9+FYRf+R RgDYeVYcQu5Ur4kllAmC+5Zk2wSaE3wSSWssztr9q8EiZ6uCeN+Lq3wxmBEmxjMG4BkP APJIDBH/ldsaMiq9IS5cY6R5UA3jMorE48/NCOntZjavwGS2h/QGg7SdMCPHqLnu41Vr MkpERC0Sz6L10BW/49BMbT7f2TOvH2ibVCRmImSs6abTvhHCtKvPEN9TgzYt+V51oPCI csVAx5QuMS4Kfxc2+rkIgNCHw4pMrygM+IcRewVaZEB1i6d7mCs4ZfncDGIwDZQQoKzi n93A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to; bh=uJm3VDtQ7R8vz/+TAfm7B10woXZjkuStG2UVs7bOsPw=; b=CPtoy7qtbCYcfoBs2m8uSVF/tU/0Mise8x0vP+uC7XtG5LJqEHLRjXSa22wbTrrUSX qdFfD33R2/mDgm5PdQsIYHohxV8s/8gVdnZF4nrwsVT0q08YxAcESyd2U0r1fKEwrLRo h7nMhGCOWhMWgmDSdq4EFG46NxCVeUWYO9mF18FTQ1uLxEc2zhy24OCeMbatamWTPRjf 0+himHOc8bduI++OaPlxUHm88W5ml2IeAqsMiM0gfdpwLxgB8425RcNykhn1ifZ3ppVE YTEI8mJ3MHq3XtAqJ4vxhe3X+xI+M3vH1heAruIMK3opgIA+MaXX500hT2pO+Q6cn09A pj0Q== X-Gm-Message-State: AKGB3mKjP6KrGDzJr4S3MYQqOo57zX086piKtcGLereTOXm33e2VSoXz +rWw7GJ4F7hdrIi7Brwcsbk/yCfn8v6uVfnMNh0Oa6st X-Google-Smtp-Source: ACJfBoteuH2hOkcGjoyljXBn93nnWRu3I3iNL8j+v4sFD2201J1GuKcOyqzT4y69mp2WZH+k7XF1H66wtPidwzQremc= X-Received: by 10.202.205.137 with SMTP id d131mr2095680oig.293.1515036841960; Wed, 03 Jan 2018 19:34:01 -0800 (PST) Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 Received: by 10.157.19.65 with HTTP; Wed, 3 Jan 2018 19:34:01 -0800 (PST) In-Reply-To: References: From: Adam Carter Date: Thu, 4 Jan 2018 14:34:01 +1100 Message-ID: Subject: Re: [gentoo-user] Expect a ~15% average slowdown if you use an Intel processor To: gentoo-user@lists.gentoo.org Content-Type: multipart/alternative; boundary="001a11351b78c96a750561eb0054" X-Archives-Salt: cbc55bdf-3630-489f-8e61-946b8b675fd3 X-Archives-Hash: 2104af87f65494964678352fcfb8f515 --001a11351b78c96a750561eb0054 Content-Type: text/plain; charset="UTF-8" > > Project Zero (Google) found it; > https://googleprojectzero.blogspot.com.au/2018/01/ > reading-privileged-memory-with-side.html > > Phoronix has done some benchmarks on the impact of the kernel based > workaround ([Kernel] Page Table Isolation (PSI) nee Kaiser) > https://www.phoronix.com/scan.php?page=article&item=linux- > more-x86pti&num=1 > > Re:AMD - Looks like Linus agrees that PTI is not required for AMD CPUs. Note that the project zero blog mentions that some AMD chips are subject to some issues*. *There's three CVEs *.* From: https://www.phoronix.com/scan.php?page=news_item&px=Linux-Tip-Git-Disable-x86-PTI *"Update:* Linus Torvalds has now ended up pulling the latest PTI fixes that also include the change to disable page table isolation for now on all AMD CPUs. The commit is in mainline for Linux 4.15 along with a few basic fixes and ensuring PAGE_TABLE_ISOLATION is enabled by default. " --001a11351b78c96a750561eb0054 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
<= div class=3D"gmail_quote">
Project Zero (Google) found it;
https://googleprojectzero.blogs= pot.com.au/2018/01/reading-privileged-memory-with-side.html <= br>

Ph= oronix has done some benchmarks on the impact of the kernel based workaroun= d ([Kernel] Page Table Isolation (PSI) nee Kaiser)
https://www.phoron= ix.com/scan.php?page=3Darticle&item=3Dlinux-more-x86pti&n= um=3D1


Re:AMD=C2=A0 - Looks like Linus agre= es that PTI is not required for AMD CPUs. Note that the project zero blog m= entions that some AMD chips are subject to some issues. Th= ere's three CVEs.

<= /div>
"Update: Linus Torvalds has now end= ed up pulling the latest PTI fixes that also include the change to disable page table isolation for now on all AMD CPUs. The commit is in mainline for Linux=20 4.15 along with a few basic fixes and ensuring PAGE_TABLE_ISOLATION is=20 enabled by default. "
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