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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EB062C6FA89 for ; Thu, 15 Sep 2022 15:09:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231151AbiIOPJx (ORCPT ); Thu, 15 Sep 2022 11:09:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48540 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231127AbiIOPIg (ORCPT ); Thu, 15 Sep 2022 11:08:36 -0400 Received: from mail-ed1-x54a.google.com (mail-ed1-x54a.google.com [IPv6:2a00:1450:4864:20::54a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A15E19837A for ; Thu, 15 Sep 2022 08:05:53 -0700 (PDT) Received: by mail-ed1-x54a.google.com with SMTP id z13-20020a05640240cd00b0045276a79364so5705316edb.2 for ; Thu, 15 Sep 2022 08:05:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date; bh=T4yulc1U4RDI/lAlxqlpzG4AIUYO9fQrzg+B84ydySw=; b=bjU5Y1Uj6lzmlmNdbvfJIhixfGz/+MKGRYCvur483Xf78D7CTzrNFlvd42wNziHYle Vw8zzRUPc25b8rF96my1wPCxCLp6TfupI3RftJKXAn7dq2QlPkGvBgmhor+As+69qJvo ts7cyW+lzlkiH21NDXMKOi08blf2XU9uBJs1YmQtKDbV3CYIcVN2LJH0wP7yDNAqAidw 2NVtGckV24urbHpg+UiXfOqAjGlT6CwNPdgB8y3HFou9URtWV43Pi53vkh8E0/1cN/xT J7/cYcC0yfDbDZhb+v1n2EFZPIQNAXrNcvBidelmwV20Zr+dNqjJnJC6KZ8B/YMPJfPN pmuQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date; bh=T4yulc1U4RDI/lAlxqlpzG4AIUYO9fQrzg+B84ydySw=; b=OCjSZt2p8SeViH6xlmtY9xw7nJSUwd8STOjhdbs+3PHcMSJ2ZRiCCDKdjkeTYk9pVT cSEP+KxmF00PW4bEOxjb0xdjN750HNrpLaZXNWnKj7xo0cNGhtsasx4e4k3qyXo7yihT moxE7NtSTufb3BE5pcyYLLnJPclYwK/yzcTd3NC/VlEiQ6N+VRFkHNOxlymuz8h0RjHl UOE8FkGm0LPsUfFbgw1LuYrS8ztoCBPaES8sB82j8WyZLpiPTGzduRKXGAuVWcljf+hA b06GWLSSBBPHbXGpTd2QQBds6F/Hfn1FjevX4VzdT3GY4ftEDYBEhkYZqRcgktaAK5Gt ztiw== X-Gm-Message-State: ACrzQf3BGDVpJPjNc6RPle06XdtRDNtJE9aHW4tytjyLOZI0vdX57cFg Tmmb0QpSTBf1zOE8uSvEVvTGO9LmiZE= X-Google-Smtp-Source: AMsMyM7l8lWYGJuBODDQ/HU6R5pl1eaYbgBKHbyvWwWvFjThOz32FII2oCbiswhP6heZLHjrzuBd6Y58nd4= X-Received: from glider.muc.corp.google.com ([2a00:79e0:9c:201:686d:27b5:495:85b7]) (user=glider job=sendgmr) by 2002:a05:6402:d06:b0:440:3e9d:77d with SMTP id eb6-20020a0564020d0600b004403e9d077dmr260579edb.286.1663254352056; Thu, 15 Sep 2022 08:05:52 -0700 (PDT) Date: Thu, 15 Sep 2022 17:04:01 +0200 In-Reply-To: <20220915150417.722975-1-glider@google.com> Mime-Version: 1.0 References: <20220915150417.722975-1-glider@google.com> X-Mailer: git-send-email 2.37.2.789.g6183377224-goog Message-ID: <20220915150417.722975-28-glider@google.com> Subject: [PATCH v7 27/43] kmsan: disable physical page merging in biovec From: Alexander Potapenko To: glider@google.com Cc: Alexander Viro , Alexei Starovoitov , Andrew Morton , Andrey Konovalov , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Christoph Hellwig , Christoph Lameter , David Rientjes , Dmitry Vyukov , Eric Biggers , Eric Dumazet , Greg Kroah-Hartman , Herbert Xu , Ilya Leoshkevich , Ingo Molnar , Jens Axboe , Joonsoo Kim , Kees Cook , Marco Elver , Mark Rutland , Matthew Wilcox , "Michael S. Tsirkin" , Pekka Enberg , Peter Zijlstra , Petr Mladek , Stephen Rothwell , Steven Rostedt , Thomas Gleixner , Vasily Gorbik , Vegard Nossum , Vlastimil Babka , kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org KMSAN metadata for adjacent physical pages may not be adjacent, therefore accessing such pages together may lead to metadata corruption. We disable merging pages in biovec to prevent such corruptions. Signed-off-by: Alexander Potapenko --- Link: https://linux-review.googlesource.com/id/Iece16041be5ee47904fbc98121b105e5be5fea5c --- block/blk.h | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/block/blk.h b/block/blk.h index d7142c4d2fefb..af02b93c1dba5 100644 --- a/block/blk.h +++ b/block/blk.h @@ -88,6 +88,13 @@ static inline bool biovec_phys_mergeable(struct request_queue *q, phys_addr_t addr1 = page_to_phys(vec1->bv_page) + vec1->bv_offset; phys_addr_t addr2 = page_to_phys(vec2->bv_page) + vec2->bv_offset; + /* + * Merging adjacent physical pages may not work correctly under KMSAN + * if their metadata pages aren't adjacent. Just disable merging. + */ + if (IS_ENABLED(CONFIG_KMSAN)) + return false; + if (addr1 + vec1->bv_len != addr2) return false; if (xen_domain() && !xen_biovec_phys_mergeable(vec1, vec2->bv_page)) -- 2.37.2.789.g6183377224-goog