From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 371A4184 for ; Wed, 22 Mar 2023 00:18:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1679444294; 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: in-reply-to:in-reply-to:references:references; bh=/jWDniPiD3ArKxuqWUYL+U69T82M+y4H2QrzlqkdHAY=; b=EKw4hw6aKa7LJWrfQ+yBE9/NBXC+WPfiCuww2j+cAaTbfTEYZjApyI4IXMZoywGcpQGJ7w qhKc801sIJUjPdJIIFvaLaDgstvM665uhxrOsz5G8v8UTrLQoo5Ge3wMC0D3lUD6WB4Jlw GKE9teBEMf9++O6FMNspIMN0ozRqmOw= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-272-vCb3AvyeOO2aOqpdADWFDw-1; Tue, 21 Mar 2023 20:18:12 -0400 X-MC-Unique: vCb3AvyeOO2aOqpdADWFDw-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 031E4101A531; Wed, 22 Mar 2023 00:18:11 +0000 (UTC) Received: from localhost (unknown [10.2.17.90]) by smtp.corp.redhat.com (Postfix) with ESMTPS id C421340C83A9; Wed, 22 Mar 2023 00:18:09 +0000 (UTC) Date: Tue, 21 Mar 2023 17:18:08 -0700 From: Chris Leech To: Hannes Reinecke Cc: Sagi Grimberg , Christoph Hellwig , Keith Busch , linux-nvme@lists.infradead.org, Chuck Lever , kernel-tls-handshake@lists.linux.dev Subject: Re: [PATCH 06/18] nvme-tcp: call 'queue->data_ready()' in nvme_tcp_data_ready() Message-ID: References: <20230321124325.77385-1-hare@suse.de> <20230321124325.77385-7-hare@suse.de> <3bd2c6b4-b276-b882-6f28-998118f96650@suse.de> Precedence: bulk X-Mailing-List: kernel-tls-handshake@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: <3bd2c6b4-b276-b882-6f28-998118f96650@suse.de> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Mar 21, 2023 at 03:09:06PM +0100, Hannes Reinecke wrote: > On 3/21/23 14:44, Sagi Grimberg wrote: > > > > > Call the original data_ready() callback in nvme_tcp_data_ready() > > > to avoid a receive stall. > > > > Can you please improve the description to include what is the stall? > > For example, does the stall exist today? If it is, I would like to > > separate such patches from this set and include them asap. > > > That is actually particular to the TLS implementation, as it uses the > 'data_ready' callback to produce the data which can be read by eg recvmsg(). > > Without this call there's no data to peruse for recvmsg(). > > But I'm not _that_ deep into networking details to know whether this is TLS > specific or an issue with any data_ready callback. > I assume the latter, but then again, who knows. > > Hence the slightly vague description. This looks like the socket callbacks end up hooked in the wrong order. Ideally it would be tcp -> tls -> nvme_tcp, while this currently looks like tcp -> nvme_tcp and then this call back to tls for decryption. I'm not quite sure how to untangle this; nvme_tcp can't just set it's own callbacks before initializing kTLS, becuse that's being done by tlshd which is going to need the userspace socket API callbacks working. - Chris