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 DF72CC433F5 for ; Tue, 29 Mar 2022 12:44:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232276AbiC2Mps (ORCPT ); Tue, 29 Mar 2022 08:45:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35686 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236489AbiC2Mn5 (ORCPT ); Tue, 29 Mar 2022 08:43:57 -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 8B9A8234578 for ; Tue, 29 Mar 2022 05:41:40 -0700 (PDT) Received: by mail-ed1-x54a.google.com with SMTP id c22-20020a50f616000000b004196649d144so10957140edn.10 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=ZKLPmfv4uiJvztn0XpUP4q1y1s80mliz378FWAFz4U2ZxjgqsbRk1f/4OGNxB2Ujpz gpRWeMJLoGizGZhn0Z7yerIu+OdI4NFSsp38J9rfSTnkp0nDT7uElyshuev55yEMmrty CyOVHdoqHo3TKfnp7taywmX4FOIAYt/hGNJxjDIbSO/9usHvR8zCINyQcA+pWjivbIlx TrPo3bHhHH/v8U0R5+w/4jXKCxyIzGnjqYLjyZvv1oBmEkGTPYMvlUgLyBRrJYTL9UUB NxSKL4Bj7+bs4QRQI4FY6pZDD2DTX3fQwJWOHhe3XDWXGHTS/FjDMZRC0hnhO1oSGI81 gWNQ== X-Gm-Message-State: AOAM532RRFbcCVpOgiqHYVA1L786hcb7YHoKR/e6oGCMW9FpvSVfOWQj yuvGf1u7jVqAvtevl/tSF0R/rryW830= 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-arch@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