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 07931C433EF for ; Wed, 18 May 2022 17:51:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241154AbiERRvX (ORCPT ); Wed, 18 May 2022 13:51:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59656 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241132AbiERRvR (ORCPT ); Wed, 18 May 2022 13:51:17 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id E93A622534 for ; Wed, 18 May 2022 10:51:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1652896274; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=49hW2Lgkit3FFJ0TGEQAkc/9Izoyz7QsMkLjDXmi4AY=; b=fzpt5aMYtzcQUknWNpFa6KdePQOcD7ZS5BqxJzhnhXL7ywqj9ZDUECE/qWLwVllipcz1yK e8NJNFnN3FEOXyGDtZloOKf1QFXogkeHDKZCDULswOlT9adcQKvEJ3VIH9aik7v6myq4t7 hNZWAXNyvEWzTwbhiCjY7pgv8z63Rak= Received: from mail-io1-f72.google.com (mail-io1-f72.google.com [209.85.166.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-219-c-Hi_WEaMG-hMiKPX-hTbA-1; Wed, 18 May 2022 13:51:13 -0400 X-MC-Unique: c-Hi_WEaMG-hMiKPX-hTbA-1 Received: by mail-io1-f72.google.com with SMTP id n5-20020a056602340500b0065a9f426e7aso716153ioz.0 for ; Wed, 18 May 2022 10:51:13 -0700 (PDT) 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:in-reply-to :references:organization:mime-version:content-transfer-encoding; bh=49hW2Lgkit3FFJ0TGEQAkc/9Izoyz7QsMkLjDXmi4AY=; b=DwHowxCq5o2J96OVvN4FmDVmSxN1hEbBkMDzmlXXHaoO190AR+R9MhIfUJZmABRUTQ dtgIh4rl0wpGDxlLVulQtjMrx410nLv9/Q03lEg9Gn47PGHRP+49qwwAPec76x+Wd4Z8 yag3rwBO1AStUD3FZOvcQb1uRp+fm+1OJ90wyHQF5a6x2wF8KJLNSfy3FyxJa4nYk5PA uKRpR3QXGfQ3xRWMe+t98yhUg3lK2aVutKpjTvg8vsZ3Vfqj88T6LKGUKkG5KAVVOCE8 9e+YAhuj48YmyXbqJGKnuFc3QuKsNLhR2wrij9bkzHRRqDwGF1s8Trx/b8Cl7A87ZJ/X ipVg== X-Gm-Message-State: AOAM530Yn7voCSBKfSfPpM7C8sYcw9VxNUEQd9KZNduNGXjzKbym1MV0 fE1nTSgg7MTBpErWdQO6SzXYt7neVBv6JQbp8x3JpgFYwTAUKnW+jEGI2bVvbrPD9vWrxlwc0Ux ckrB7hpM2n0iT1hEz1QVb1Mo+ X-Received: by 2002:a05:6638:dc7:b0:32b:a483:16b8 with SMTP id m7-20020a0566380dc700b0032ba48316b8mr423070jaj.66.1652896272819; Wed, 18 May 2022 10:51:12 -0700 (PDT) X-Google-Smtp-Source: ABdhPJy4yot0L8H1GFnxd+jBFDsw6Yt7jnmhEuw0qSATO4iI9tLeFnhC04lgVq81N4r1GIYOBFpfHg== X-Received: by 2002:a05:6638:dc7:b0:32b:a483:16b8 with SMTP id m7-20020a0566380dc700b0032ba48316b8mr423057jaj.66.1652896272606; Wed, 18 May 2022 10:51:12 -0700 (PDT) Received: from redhat.com ([38.15.36.239]) by smtp.gmail.com with ESMTPSA id g15-20020a92dd8f000000b002cf5aae6645sm727757iln.2.2022.05.18.10.51.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 18 May 2022 10:51:12 -0700 (PDT) Date: Wed, 18 May 2022 11:51:10 -0600 From: Alex Williamson To: Wan Jiabing Cc: Paolo Bonzini , Yi Liu , Kevin Tian , Jason Gunthorpe , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] kvm/vfio: Fix potential deadlock problem in vfio Message-ID: <20220518115110.23a0e929.alex.williamson@redhat.com> In-Reply-To: <20220517023441.4258-1-wanjiabing@vivo.com> References: <20220517023441.4258-1-wanjiabing@vivo.com> Organization: Red Hat MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 17 May 2022 10:34:41 +0800 Wan Jiabing wrote: > Fix following coccicheck warning: > ./virt/kvm/vfio.c:258:1-7: preceding lock on line 236 > > If kvm_vfio_file_iommu_group() failed, code would goto err_fdput with > mutex_lock acquired and then return ret. It might cause potential > deadlock. Move mutex_unlock bellow err_fdput tag to fix it. > > Fixes: d55d9e7a45721 ("kvm/vfio: Store the struct file in the kvm_vfio_group") > Signed-off-by: Wan Jiabing > --- > virt/kvm/vfio.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/virt/kvm/vfio.c b/virt/kvm/vfio.c > index 8f9f7fffb96a..ce1b01d02c51 100644 > --- a/virt/kvm/vfio.c > +++ b/virt/kvm/vfio.c > @@ -252,8 +252,8 @@ static int kvm_vfio_group_set_spapr_tce(struct kvm_device *dev, > break; > } > > - mutex_unlock(&kv->lock); > err_fdput: > + mutex_unlock(&kv->lock); > fdput(f); > return ret; > } Applied to vfio next branch for v5.19. Thanks! Alex