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 CBE7BC433EF for ; Tue, 29 Mar 2022 12:43:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236336AbiC2MpR (ORCPT ); Tue, 29 Mar 2022 08:45:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33946 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236498AbiC2Mn5 (ORCPT ); Tue, 29 Mar 2022 08:43:57 -0400 Received: from mail-ed1-x549.google.com (mail-ed1-x549.google.com [IPv6:2a00:1450:4864:20::549]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8DBD3235747 for ; Tue, 29 Mar 2022 05:41:40 -0700 (PDT) Received: by mail-ed1-x549.google.com with SMTP id x1-20020a50f181000000b00418f6d4bccbso10995002edl.12 for ; Tue, 29 Mar 2022 05:41:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=Eb/Abij6XQ3iqbkwUGDaEHK0fSpQBifUF5HLZH6JcRc=; b=Krkj/S1jh5/H05+jCH+MSNkam2il8xetzlLh3mofzSw3z1EUZVLwTavHzuR07R13in fg9//+1CujBKky+Yg98dxF0i9pubcLdyg1zZweQ1XjNQleJiDN/XoHbConhYKPEsItrW Hqor3bLi18aLxBGMha4/9ZF65JCN2E/xs869FWNbVFPNZlCCTsmL0+sn19SYqkD+nycO 8yokw7MAHVM6QSu96rl3jBfgqKH9wHHao396wVZYsEKnozljUrrFpvS6mVwzvzPs2PCk rZme07+nb4Ir4EhmUhbog2UgvqaC31UAfTNt+DsOKVK0oofUTAwJkiObvGLB48vzpwDI J6HA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=Eb/Abij6XQ3iqbkwUGDaEHK0fSpQBifUF5HLZH6JcRc=; b=V2agB6d9nu81CjHCH4v47slIiQhjMt01mVriRBkrxR9TZDra1lkW+WJcry5xmIkfiJ cl4J54L+qIDcHahRRwu9D+R+8xScL7nkQX6WOk1OPfWUMX/mah5mYHD3HmXrdgznrekk hEttfQTY24Jnyg8RqKpG5nD3EATw6IghplAPZwirTh3EiizIbH0ENmL5kMw1aVc8B/vH mqu+1OACkuroiGZK2wWYXDKTeYD3Bdo9QYJvhygnmdduzZ93rDQKio4LD2E41GKXMydq lk25lV+dFbls/h0JorgY4CQpxCu/jCCA6Unn0kEAMDshGwm8+BfPCUK3NfkKng8zEgtD OhIA== X-Gm-Message-State: AOAM5322Ig0QvMqHVogFUTlQOloIskkh8jOWsNehS2AptXcSrXrwJMb1 985Hq/wZoVSAGOLCjfUAGn61/HINhLw= X-Google-Smtp-Source: ABdhPJxL1GeaEMAohn+FBay8BfgBp3WhpguNB4XCKO3e3e1LP1mlhUbZL/tt/mlN/CXlhJVrae+cgzEdiVU= X-Received: from glider.muc.corp.google.com ([2a00:79e0:15:13:36eb:759:798f:98c3]) (user=glider job=sendgmr) by 2002:a17:907:7f09:b0:6e0:395d:cc88 with SMTP id qf9-20020a1709077f0900b006e0395dcc88mr34433043ejc.566.1648557698741; Tue, 29 Mar 2022 05:41:38 -0700 (PDT) Date: Tue, 29 Mar 2022 14:39:55 +0200 In-Reply-To: <20220329124017.737571-1-glider@google.com> Message-Id: <20220329124017.737571-27-glider@google.com> Mime-Version: 1.0 References: <20220329124017.737571-1-glider@google.com> X-Mailer: git-send-email 2.35.1.1021.g381101b075-goog Subject: [PATCH v2 26/48] kmsan: virtio: check/unpoison scatterlist in vring_map_one_sg() From: Alexander Potapenko To: glider@google.com Cc: Alexander Viro , Andrew Morton , Andrey Konovalov , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Christoph Hellwig , Christoph Lameter , David Rientjes , Dmitry Vyukov , 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 , Steven Rostedt , Thomas Gleixner , Vasily Gorbik , Vegard Nossum , Vlastimil Babka , 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-kernel@vger.kernel.org If vring doesn't use the DMA API, KMSAN is unable to tell whether the memory is initialized by hardware. Explicitly call kmsan_handle_dma() from vring_map_one_sg() in this case to prevent false positives. Signed-off-by: Alexander Potapenko Acked-by: Michael S. Tsirkin --- Link: https://linux-review.googlesource.com/id/I211533ecb86a66624e151551f83ddd749536b3af --- drivers/virtio/virtio_ring.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 962f1477b1fab..461e08f7f0a0f 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include @@ -331,8 +332,15 @@ static dma_addr_t vring_map_one_sg(const struct vring_virtqueue *vq, struct scatterlist *sg, enum dma_data_direction direction) { - if (!vq->use_dma_api) + if (!vq->use_dma_api) { + /* + * If DMA is not used, KMSAN doesn't know that the scatterlist + * is initialized by the hardware. Explicitly check/unpoison it + * depending on the direction. + */ + kmsan_handle_dma(sg_page(sg), sg->offset, sg->length, direction); return (dma_addr_t)sg_phys(sg); + } /* * We can't use dma_map_sg, because we don't use scatterlists in -- 2.35.1.1021.g381101b075-goog