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=-14.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=ham 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 E8C91C54FD0 for ; Thu, 23 Apr 2020 19:15:23 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 9D6D420661 for ; Thu, 23 Apr 2020 19:15:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="LZW0pkrv" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9D6D420661 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 48D8D8E0007; Thu, 23 Apr 2020 15:15:23 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 463558E0003; Thu, 23 Apr 2020 15:15:23 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 353018E0007; Thu, 23 Apr 2020 15:15:23 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0161.hostedemail.com [216.40.44.161]) by kanga.kvack.org (Postfix) with ESMTP id 1D6918E0003 for ; Thu, 23 Apr 2020 15:15:23 -0400 (EDT) Received: from smtpin15.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id C4137584D for ; Thu, 23 Apr 2020 19:15:22 +0000 (UTC) X-FDA: 76740073284.15.stamp94_2ee3c8e704b54 X-HE-Tag: stamp94_2ee3c8e704b54 X-Filterd-Recvd-Size: 6805 Received: from mail-pf1-f194.google.com (mail-pf1-f194.google.com [209.85.210.194]) by imf31.hostedemail.com (Postfix) with ESMTP for ; Thu, 23 Apr 2020 19:15:22 +0000 (UTC) Received: by mail-pf1-f194.google.com with SMTP id x15so3462626pfa.1 for ; Thu, 23 Apr 2020 12:15:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=Ek56n0CK+1hwhAlORvOJbkSp+pZjz8ub3O4FPW6fegw=; b=LZW0pkrvnHuWxfeEClmKamrRUgHi5BAFzntlVek/cSmdz910IzpsICDx7fcU2+0yr+ q0JZyfglo/EU2m5Ow/fJ0cEoF4tSJbo1lJMbf8+mbK4X0nUZKWGwYqYUNPxroWqycaid OuQq1nGSUUGiyo6N5pTsn0Z+NkaKaRmLlYYtpIIsjZFTZyqnQiVUl5aw4ws/NX6a5/g8 xIDCtGD+i/S2goj7EaRMEXh80R6+6LoZP57nfK5jaZHZh8CCBowqkOwlonE+HMz7po1D UPqNVFhWNpK1dgW9zBWYwNCUTy/qIZDnkDKJYVKCTz32Uyz9o0R8WEOio4jmc/XTUGqa 1TXA== 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; bh=Ek56n0CK+1hwhAlORvOJbkSp+pZjz8ub3O4FPW6fegw=; b=Sq5S+/UZPEkIj6nXA+6TzgOmKBo9bXjUwTwWnQ3udSc4oslzmC9KP0eRQIsBjiQP+e Xz/nowxL+T3aJ0dGoiDjwNFlklZoSVBWAD98G36PQBNgi0VBLao/tPQ/MZeGWZ3/8yGR iwzaLhG+pnlNybZ0ecYL4becH/I/pFX9B+xRDns6otVt17T8/i5Bzm1ANwv1xnIOWAPr /awQjZcxrjfB6oWS9Htr/mFr8hAP5gtlyPJzaxkWsHXk9i5TS+/Cx3JkC6esNIPLnHlU cmCS873Yp3IEqq5JVPIxU86/ouXwYo4yP6KELpj9zg6sXffJrSs0Rblp+ng5e9inL0S5 0QPA== X-Gm-Message-State: AGi0PuYE887ukWMndTp8MAK4pF4xNnMPWSEcW3UnW8ebmhvwk6ntb5ph 0KkwuMp2yftD1YECzBESBCybD2ZGcNBUVPHdD9A3QQ== X-Google-Smtp-Source: APiQypI8pgXCHLq4rShXRNIAh14MC4P1iqNUsYUjyeEbkFiJuz8q/rRAxX+IthWgcLOmD3ylS2OzbRO4IHCql0UZlLo= X-Received: by 2002:a62:4e87:: with SMTP id c129mr5257611pfb.178.1587669321015; Thu, 23 Apr 2020 12:15:21 -0700 (PDT) MIME-Version: 1.0 References: <20200325161249.55095-1-glider@google.com> <20200325161249.55095-13-glider@google.com> In-Reply-To: <20200325161249.55095-13-glider@google.com> From: Andrey Konovalov Date: Thu, 23 Apr 2020 21:15:09 +0200 Message-ID: Subject: Re: [PATCH v5 12/38] kmsan: x86: sync metadata pages on page fault To: Alexander Potapenko Cc: Ingo Molnar , Vegard Nossum , Dmitry Vyukov , Marco Elver , Linux Memory Management List , Alexander Viro , Andreas Dilger , Andrew Morton , Andrey Ryabinin , Andy Lutomirski , Ard Biesheuvel , Arnd Bergmann , Christoph Hellwig , Christoph Hellwig , "Darrick J. Wong" , "David S. Miller" , Dmitry Torokhov , Eric Biggers , Eric Dumazet , Eric Van Hensbergen , Greg Kroah-Hartman , Harry Wentland , Herbert Xu , Ilya Leoshkevich , Jason Wang , Jens Axboe , Marek Szyprowski , Mark Rutland , "Martin K. Petersen" , Martin Schwidefsky , Matthew Wilcox , "Michael S . Tsirkin" , Michal Hocko , Michal Simek , Petr Mladek , Qian Cai , Randy Dunlap , Robin Murphy , Sergey Senozhatsky , Steven Rostedt , Takashi Iwai , "Theodore Ts'o" , Thomas Gleixner , Vasily Gorbik , Wolfram Sang Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Mar 25, 2020 at 5:13 PM wrote: > > KMSAN assumes shadow and origin pages for every allocated page are > accessible. For pages in vmalloc region those metadata pages reside in > [VMALLOC_END, VMALLOC_META_END), therefore we must sync a bigger memory > region. > > Signed-off-by: Alexander Potapenko > To: Alexander Potapenko > Cc: Ingo Molnar > Cc: Vegard Nossum > Cc: Dmitry Vyukov > Cc: Marco Elver > Cc: Andrey Konovalov > Cc: linux-mm@kvack.org Reviewed-by: Andrey Konovalov > > --- > > Change-Id: I0d54855489870ef1180b37fe2120b601da464bf7 > --- > arch/x86/mm/fault.c | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > > diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c > index a51df516b87bf..d22e373fa2124 100644 > --- a/arch/x86/mm/fault.c > +++ b/arch/x86/mm/fault.c > @@ -331,11 +331,21 @@ static void dump_pagetable(unsigned long address) > > void vmalloc_sync_mappings(void) > { > +#ifndef CONFIG_KMSAN > /* > * 64-bit mappings might allocate new p4d/pud pages > * that need to be propagated to all tasks' PGDs. > */ > sync_global_pgds(VMALLOC_START & PGDIR_MASK, VMALLOC_END); > +#else > + /* > + * For KMSAN, make sure metadata pages for vmalloc area and modules are > + * also synced. > + */ > + sync_global_pgds(VMALLOC_START & PGDIR_MASK, VMALLOC_META_END); > + sync_global_pgds(MODULES_SHADOW_START & PGDIR_MASK, > + MODULES_ORIGIN_END); > +#endif > } > > void vmalloc_sync_unmappings(void) > @@ -360,7 +370,17 @@ static noinline int vmalloc_fault(unsigned long address) > pte_t *pte; > > /* Make sure we are in vmalloc area: */ > +#ifdef CONFIG_KMSAN > + /* > + * For KMSAN, make sure metadata pages for vmalloc area and modules are > + * also synced. > + */ > + if (!(address >= VMALLOC_START && address < VMALLOC_META_END) && > + !(address >= MODULES_SHADOW_START && > + address < MODULES_ORIGIN_END)) > +#else > if (!(address >= VMALLOC_START && address < VMALLOC_END)) > +#endif > return -1; > > /* > -- > 2.25.1.696.g5e7596f4ac-goog >