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 C78AFC433FE for ; Thu, 25 Nov 2021 18:06:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1356760AbhKYSJa (ORCPT ); Thu, 25 Nov 2021 13:09:30 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:21945 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239213AbhKYSH3 (ORCPT ); Thu, 25 Nov 2021 13:07:29 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1637863457; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type; bh=uqHYC6pMdILCZt4L46t3fYUcohv6tOiNRcfAVmZ0lZA=; b=AX44U2Yt3XjNwY/ajB1oxIo/wQqpc+H7mNJI980qCXpd2KnzfAx7XJljXiNp0Td9UNDwwc B0qF62wJERbHqlSBZaGUsle9HQiNoMhp6NOWz5Ndd0itgSV685R+dF372GOjAYcNwa5Mvj sjo4A2gmvhhBRODKCpvFOJ39216raeI= Received: from mail-ed1-f70.google.com (mail-ed1-f70.google.com [209.85.208.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-106-O0Xs8O5CPoOboC7wHD-gNQ-1; Thu, 25 Nov 2021 13:04:16 -0500 X-MC-Unique: O0Xs8O5CPoOboC7wHD-gNQ-1 Received: by mail-ed1-f70.google.com with SMTP id y9-20020aa7c249000000b003e7bf7a1579so6028364edo.5 for ; Thu, 25 Nov 2021 10:04:16 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:mime-version :content-disposition; bh=uqHYC6pMdILCZt4L46t3fYUcohv6tOiNRcfAVmZ0lZA=; b=O1I8Jr4WODYQ86hAGlv4zEvtaPm/WysGaudIERCWGnLHBpyEvRaLrD0UjaLzASpi8R uHXv/5wVTAEHmcS/E2sZhu9Yk95FM6IxF8scolk/pW4P3bl6XvfPFWVwgKDl++XKWDIY C+nBRcQc8X16WoBnWFbDt01lMhwKr+1co4QA06ht1N5XvJk1bSB3lcfCaiddwu+tzS9O gVgi0gIUI8DxHJVlmH8LnqSxSrKFiMOy4iG7Z/TsXnpy9jEEsVxYvkHdftn6SLG7OopZ iBXNux8DTcTus2Cg38mq5QcVcQ4K0WbkKS495dSwqVAawDTbYiJsnIM9A03+4HKS0nvx 8OnQ== X-Gm-Message-State: AOAM531xaQevVCbnjxS0rvOs3ynoI7KEayRVSKJcDmqr6LLT3jkyNQl0 6d8+a9JrcsKuZLXykuJzT/Afke4XTPvFSPP89hpz7fo2S0ecmU4KVjxKRtPshflrMjbt/oxtm06 16A7b1DINtSS4TniKcie2VqtwJ+k/NqfKJ8kQuOTVytGNxjFsYgf86CH5NRs7bJTcAiW4Kw== X-Received: by 2002:a17:906:5951:: with SMTP id g17mr34494256ejr.315.1637863454900; Thu, 25 Nov 2021 10:04:14 -0800 (PST) X-Google-Smtp-Source: ABdhPJyUwyeLJh7uyU1G5zbFj303QzV/bRNx8rnoSzog0EBaXN/XxDE9bEwdzbCGmSFxfoUoiZ3rxA== X-Received: by 2002:a17:906:5951:: with SMTP id g17mr34494215ejr.315.1637863454657; Thu, 25 Nov 2021 10:04:14 -0800 (PST) Received: from redhat.com ([176.12.197.47]) by smtp.gmail.com with ESMTPSA id h10sm2399113edj.1.2021.11.25.10.04.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 25 Nov 2021 10:04:14 -0800 (PST) Date: Thu, 25 Nov 2021 13:04:11 -0500 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: Laurent Vivier , Matt Mackall , Herbert Xu , linux-crypto@vger.kernel.org Subject: [PATCH] hwrng: virtio - unregister device before reset Message-ID: <20211125180343.134505-1-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Mailer: git-send-email 2.27.0.106.g8ac3dc51b1 X-Mutt-Fcc: =sent Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org unregister after reset is clearly wrong - device can be used while it's reset. There's an attempt to protect against that using hwrng_removed but it seems racy since access can be in progress when the flag is set. Just unregister, then reset seems simpler and cleaner. NB: we might be able to drop hwrng_removed in a follow-up patch. Signed-off-by: Laurent Vivier Signed-off-by: Michael S. Tsirkin --- NB: lightly tested. Don't know much about rng. Any reviewers? drivers/char/hw_random/virtio-rng.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/char/hw_random/virtio-rng.c b/drivers/char/hw_random/virtio-rng.c index b2bf78b25630..e856df7e285c 100644 --- a/drivers/char/hw_random/virtio-rng.c +++ b/drivers/char/hw_random/virtio-rng.c @@ -179,9 +179,9 @@ static void remove_common(struct virtio_device *vdev) vi->data_avail = 0; vi->data_idx = 0; complete(&vi->have_data); - virtio_reset_device(vdev); if (vi->hwrng_register_done) hwrng_unregister(&vi->hwrng); + virtio_reset_device(vdev); vdev->config->del_vqs(vdev); ida_simple_remove(&rng_index_ida, vi->index); kfree(vi); -- MST