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=-5.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 652D9C433E0 for ; Mon, 15 Mar 2021 09:49:52 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4523B64DAE for ; Mon, 15 Mar 2021 09:49:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4523B64DAE Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Type: Content-Transfer-Encoding:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:CC:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=mqvlry9/Fqmd5jQ+LHEFU107plfNparAleyQHwfl74E=; b=AEBH7rKSa2hGPgnfmJ/Ppks7L 2Mfh/bx0adVvu0ba6bDZ33mj6VmGVX+Vj46/LGqrOs73GYONCpZ+G0kMGARcPImVmXerOyzcTsBr+ MJY2NJ73jwf8Nb5/DDgsbvvPOezv8c5Ws5TaO6kGSKxDzPsWoPmKH4IubvXtt9vXT8nZsrVZ1kwZ+ VG29RcFIZiFisPav2XgBPxkArdHaid/2P2kAe32PD+VOtZRd0HFO0jv6bmLQ3GHVdlJ070UwMftgc q3OMlpwYv1GYucgIdXrIlvwfXPme0B8fECkyy5ZR8MBILbBZ+o04GreuNTW0geUXEQNuNxVuWpR1I i9OI1Vnpw==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lLjpW-00FQtz-Sd; Mon, 15 Mar 2021 09:48:07 +0000 Received: from frasgout.his.huawei.com ([185.176.79.56]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lLjmq-00FQ6v-IT for linux-arm-kernel@lists.infradead.org; Mon, 15 Mar 2021 09:45:25 +0000 Received: from fraeml706-chm.china.huawei.com (unknown [172.18.147.207]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4DzWXN3sNhz680KG; Mon, 15 Mar 2021 17:36:52 +0800 (CST) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by fraeml706-chm.china.huawei.com (10.206.15.55) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2106.2; Mon, 15 Mar 2021 10:45:10 +0100 Received: from [10.210.166.140] (10.210.166.140) by lhreml724-chm.china.huawei.com (10.201.108.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2106.2; Mon, 15 Mar 2021 09:45:09 +0000 Subject: Re: arm64 syzbot instances To: Arnd Bergmann , Dmitry Vyukov CC: Mark Rutland , Marc Zyngier , "Will Deacon" , Ard Biesheuvel , Linux ARM , syzkaller , LKML , "Peter Maydell" , =?UTF-8?Q?Alex_Benn=c3=a9e?= References: From: John Garry Message-ID: <48347b4d-9194-16f2-95a0-c3eb55ca9a80@huawei.com> Date: Mon, 15 Mar 2021 09:43:02 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.1.2 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US X-Originating-IP: [10.210.166.140] X-ClientProxiedBy: lhreml718-chm.china.huawei.com (10.201.108.69) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210315_094520_919338_4E3744DD X-CRM114-Status: GOOD ( 13.08 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 12/03/2021 10:52, Arnd Bergmann wrote: > On Fri, Mar 12, 2021 at 11:38 AM Dmitry Vyukov wrote: >> On Fri, Mar 12, 2021 at 11:11 AM Arnd Bergmann wrote: >> >> It does not happen too often on syzbot so far, so let's try to do the >> right thing first. >> I've filed: https://bugs.launchpad.net/qemu/+bug/1918917 >> with a link to this thread. To be fair, I don't fully understand what >> I am talking about, I hope I proxied your description properly. > > Thanks, looks good. I provided a little more detail in a comment there. > > Arnd > . > From looking at the bug report, my impression is that this is a qemu issue, as the logical IO space is mapped to the PCI host bridge IO space, and qemu does not handle accesses to that CPU addressable region at all. As Arnd said. However, we really should not be accessing logical IO ports 0 or 0x2f8 at all via ttyS3 if not enumerated from PCI device at that logical IO port. That is what I think anyway, as who knows what device - if any - really exists at that location. That is why I had this patch to just stop accesses to legacy IO port regions on arm64: https://lore.kernel.org/lkml/1610729929-188490-2-git-send-email-john.garry@huawei.com/ Thanks, John _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel