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 X-Spam-Level: X-Spam-Status: No, score=-17.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 90DCBC4743C for ; Mon, 21 Jun 2021 12:21:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7431C61206 for ; Mon, 21 Jun 2021 12:21:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229837AbhFUMYK (ORCPT ); Mon, 21 Jun 2021 08:24:10 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:22271 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229621AbhFUMYI (ORCPT ); Mon, 21 Jun 2021 08:24:08 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1624278113; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=VhDAKKgaNDrSL7iSXcPu9LD5gECJffFFHIw26sWyyR0=; b=EB4NhdvXbk8MaJC3Ss43fjYmDXmrttqEckL9cR3UI7uIFA+MbJB/aozcYf5ov0MNhgMQU+ 8QAvaYBRvJJoZOFFIsqomdD4UuWwHM3qVSceOegL/1ssg3k+MELf8c+KG9MnOzcKVlTHnB sB0x1zl6wqI4xTjKvGk2jD2Z2qrMVko= Received: from mail-wm1-f71.google.com (mail-wm1-f71.google.com [209.85.128.71]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-111-aOPc2N2jORq-EB6JczOgeg-1; Mon, 21 Jun 2021 08:21:52 -0400 X-MC-Unique: aOPc2N2jORq-EB6JczOgeg-1 Received: by mail-wm1-f71.google.com with SMTP id w186-20020a1cdfc30000b02901ced88b501dso5768468wmg.2 for ; Mon, 21 Jun 2021 05:21:52 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:reply-to:subject:to:references:from:message-id :date:user-agent:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=VhDAKKgaNDrSL7iSXcPu9LD5gECJffFFHIw26sWyyR0=; b=eGov7Ed34O+ZSTdWctpauNtmr4H2zkv9t/AEec9ufZlMaRZfsc3Qn14RUvJ5vtDC4u N/XB2Px6ev9lvPEJX0OncgrEOFuY3sl048GzO6Pgvj51wqHWXobrb2rwAtXNImZEDBPl XD8Zn8m+tfaAGnbdI07lTmfBQz4yBkpldKvSvPO9BxmRJq3jKlUm+VUTSLEGwhLjcnHQ y65EBqyzzlR0fyWixflAYYvZROAvuZIxV27mU9ZXTVhoJ0CIysevnzvqhKo/U5Pr2Qi6 sFgbh+xKtARYTs/ELb+25V/9Lod1Z9aXDwfHkCUVPOAd5BICLd4/w1mz4brb/nHmY3sI idNQ== X-Gm-Message-State: AOAM533F03w53vez1kPkS/s+jrd62MqZAWfdDA1hGiv9X/w+6jgBadHj AMQApdectM58VvNuAaLKzWWHjYn+qMhb5xEd+ACaBAv+D4u/xo9JQ2Ce51TJk65+yP/FSkmUIb7 Qkeupxkez00Nsc3e2VfWrVRYV X-Received: by 2002:a7b:ce8e:: with SMTP id q14mr12106037wmj.33.1624278110436; Mon, 21 Jun 2021 05:21:50 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxFLQpGIAVfisiyTY6nyCXRe3QRWDsB4/y9R3ja660K2K9yyGgRerGQ+R2pQj2G1e1aEWhFSw== X-Received: by 2002:a7b:ce8e:: with SMTP id q14mr12106002wmj.33.1624278110220; Mon, 21 Jun 2021 05:21:50 -0700 (PDT) Received: from [192.168.43.95] ([37.173.110.237]) by smtp.gmail.com with ESMTPSA id l23sm16824154wmc.5.2021.06.21.05.21.49 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 21 Jun 2021 05:21:49 -0700 (PDT) Reply-To: eric.auger@redhat.com Subject: Re: [PATCH] KVM: arm/arm64: Fix KVM_VGIC_V3_ADDR_TYPE_REDIST read To: eric.auger.pro@gmail.com, stable@vger.kernel.org, maz@kernel.org, linux-kernel@vger.kernel.org, kvmarm@lists.cs.columbia.edu References: <20210621121839.792649-1-eric.auger@redhat.com> From: Eric Auger Message-ID: Date: Mon, 21 Jun 2021 14:21:48 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: <20210621121839.792649-1-eric.auger@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 6/21/21 2:18 PM, Eric Auger wrote: > When reading the base address of the a REDIST region > through KVM_VGIC_V3_ADDR_TYPE_REDIST we expect the > redistributor region list to be populated with a single > element. > > However list_first_entry() expects the list to be non empty. > Instead we should use list_first_entry_or_null which effectively > returns NULL if the list is empty. > > Fixes: dbd9733ab674 ("KVM: arm/arm64: Replace the single rdist region by a list") > Cc: # v4.19 > Signed-off-by: Eric Auger > Reported-by: Gavin Shan > Signed-off-by: Marc Zyngier > Link: https://lore.kernel.org/r/20210412150034.29185-1-eric.auger@redhat.com Maybe I should I prefixed the patch with [stable-4.19]. This is already on master and in various stable but did not apply on 4.19 Thanks Eric > --- > virt/kvm/arm/vgic/vgic-kvm-device.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c > index 6ada2432e37c..71d92096776e 100644 > --- a/virt/kvm/arm/vgic/vgic-kvm-device.c > +++ b/virt/kvm/arm/vgic/vgic-kvm-device.c > @@ -95,8 +95,8 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write) > r = vgic_v3_set_redist_base(kvm, 0, *addr, 0); > goto out; > } > - rdreg = list_first_entry(&vgic->rd_regions, > - struct vgic_redist_region, list); > + rdreg = list_first_entry_or_null(&vgic->rd_regions, > + struct vgic_redist_region, list); > if (!rdreg) > addr_ptr = &undef_value; > else