Received: by 2002:a05:6a10:a0d1:0:0:0:0 with SMTP id j17csp373422pxa; Fri, 14 Aug 2020 06:44:45 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyZA8Qv0eXGMkRgSC0x81b6FXQcqmv75W88VIfmoh0rlJuVmcOAHZdXv1U8DjK/evWO87uQ X-Received: by 2002:a05:6402:1386:: with SMTP id b6mr2269304edv.296.1597412685101; Fri, 14 Aug 2020 06:44:45 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1597412685; cv=none; d=google.com; s=arc-20160816; b=jdWBh/lKig4W7IeOAbWUfh/XsBliOLgqyTgAIQu6rU3sgBA88XbY+CJiV5PaV6+fGm HhMep9FlpX8OHdHofyboowptznhJDgXKCQqXWfWaFQx/pPzyFzAYBT3DaXlG/NEKgg98 mXqXIj4zPNGNNZk398ST15DKDA3vWfDcW/rExgZz5/+r9omyG2Q8hC+Q3AwMGNiOPGxu cjWA8I3Lqr7XoWU9QQMPqZtdVrr5+Q+YGmmO9256lkeIKmsvVMQ0PJlClNm62gqFuVcu sBMnBCqGZU8X9o5qYgtvKMUjZyuB4Rf+jUYNg0JUPuqEgNBHCYoX1bDLdU/MVhRljOFS zsJw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding :content-language:in-reply-to:mime-version:user-agent:date :message-id:references:cc:to:from:subject; bh=8z//n7pC2Agrfm5HDwgp8dxM7czF3Kd7x4m6XKnFzUM=; b=cAiKXOaNBzG3t/bZaZkrqLaX2D5ASd1VBUxX+dSdBwTG+geL7JoWNf4Rjo6RErbCGu UIkK73dPrdO0hVVsbaLV8xJyKwRrcGReTIgHqM2UKv6x2ZEXrA8ldgSMQSx24LBEgADW AozUEEVUYxBl7rH+L3DyKveuK2NLN+X27ALLBlVWv7gHg+69y5gyfuWby94YH2v2T3t1 3oDUPnH2+/CKcXhgaxIowxl8nTHa6EmbY4SK7CEb9myvscdXeOM8VUpE9vqVHc27XJKl Zf4Fp2Pp5CfBOZ5ggwPETJuXItww0RzajvNPDSrSXg/0W3pQH8x0zV5nXzq9BIqgM4xH X4HQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id v7si5278843edq.227.2020.08.14.06.44.22; Fri, 14 Aug 2020 06:44:45 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727081AbgHNNkL (ORCPT + 99 others); Fri, 14 Aug 2020 09:40:11 -0400 Received: from lhrrgout.huawei.com ([185.176.76.210]:2607 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726139AbgHNNkK (ORCPT ); Fri, 14 Aug 2020 09:40:10 -0400 Received: from lhreml724-chm.china.huawei.com (unknown [172.18.7.108]) by Forcepoint Email with ESMTP id 7163B571FFE3D7393BC5; Fri, 14 Aug 2020 14:40:08 +0100 (IST) Received: from [127.0.0.1] (10.47.4.107) 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 15.1.1913.5; Fri, 14 Aug 2020 14:40:07 +0100 Subject: Re: nvme crash - Re: linux-next: Tree for Aug 13 From: John Garry To: Christoph Hellwig CC: linux-nvme , Stephen Rothwell , Linux Next Mailing List , Linux Kernel Mailing List , , Robin Murphy , References: <20200813155009.GA2303@infradead.org> <81e42d30-ede3-d7b0-ad7b-8192bcf27a4c@huawei.com> <20200814120824.GB1872@infradead.org> <895b0c2f-52eb-bd72-7cbf-aa6808c018d2@huawei.com> Message-ID: <4f01dd86-62da-84bd-0ae4-7e31b5484514@huawei.com> Date: Fri, 14 Aug 2020 14:37:52 +0100 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: <895b0c2f-52eb-bd72-7cbf-aa6808c018d2@huawei.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.47.4.107] X-ClientProxiedBy: lhreml726-chm.china.huawei.com (10.201.108.77) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 14/08/2020 14:07, John Garry wrote: > > BTW, as for the DMA/sg scatterlist code, it so happens in this case that > we try the dma alloc for size=0 in nvme_alloc_queue() - I know an > allocation for size=0 makes no sense, but couldn't we bit a bit more > robust? it's giving ZERO_SIZE_PTR, which we deference, so ignore me...