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=-8.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_PASS,USER_IN_DEF_DKIM_WL 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 614A6C43381 for ; Mon, 18 Mar 2019 16:09:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 30C2620863 for ; Mon, 18 Mar 2019 16:09:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="oxnKC1Tg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727495AbfCRQJC (ORCPT ); Mon, 18 Mar 2019 12:09:02 -0400 Received: from mail-pg1-f194.google.com ([209.85.215.194]:36146 "EHLO mail-pg1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726958AbfCRQJA (ORCPT ); Mon, 18 Mar 2019 12:09:00 -0400 Received: by mail-pg1-f194.google.com with SMTP id r124so11723218pgr.3 for ; Mon, 18 Mar 2019 09:08:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=4jnBV7KXAwRH/SBiWunplsgAO5XC9ZDTjIPOKm8iM+g=; b=oxnKC1TgVy0AfRUFzdhntQ4TnaWjo/dHSXwb/USSzN9iByb1J8qb9RNkXwR6mHS+mw U0ldrfn6mRkKtGFn2Svuia32YqyzgHr8lgGpA8Ip0euwMX1zgcj9IEez46oWi1IBddSU gwBvQTSUaqVbn9YXiSr6jTBOA8Xv5UO8CN9pXByf2+OfL6o1mjVRgyqe5P+Xg2G+PiCf NrrQ0yX3K59cnkolhi014Qa1wO07CtueVQk+/0EtrVmsp+hp6aDS9QuNbVuDWXjtk1vJ lpuGAyImKDa6JNaKflwTKUzEOC9JqWe+LJv/B30MBc7OlHCI7rVxIEK1sErhlvMqw4PK B6tw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=4jnBV7KXAwRH/SBiWunplsgAO5XC9ZDTjIPOKm8iM+g=; b=tFEiwsNVg6kuOhLAU7wIC2V2Nlin1P6Zg406KHwEFUl8nrkYR3hpuwVV33s5C3Sq/a vr2yUFJ5KgYxy2pqmSIpFU2y3MUKr4rR5cIh1HYAt+bOsvfQbvRN6H1pl2fqHM0PAwHw UabskdU7HcBoEveC3r2uS034WHy082HK+nH3ZPx9PW1AUoZW21iMSZrMI9PM0OPqRHLO DZHVBmuj4CE0y1z8dWp/lJi90cHKH0tDhoRIFvGbPO274UQTQ+4AWaPxl9O2uXZnRpe7 6yHIcKAXaDb1iPYEmLDRsbcGz/SFW1ItQo1M6D7BFG0QXrCd8zYOyiQv65iAoZfDOdEF k+eA== X-Gm-Message-State: APjAAAVBv5d/PY/d7JSZjSzglTdfkILYY+KuaObZ72b/ftU1TOArfPck TMGC0JFPX1pkQ2eP3BCp56UJLMX4+Cn4gRLV/qXZxA== X-Google-Smtp-Source: APXvYqz4X+86iXGnn3Nho9z6FaNxwbl9pQbIbD8Gz0QIEPwnGUaSMpR4psZ3WXMcGuMVMNFbcG/Runz5qQVKQSjPXF0= X-Received: by 2002:a62:4299:: with SMTP id h25mr19703730pfd.165.1552925338999; Mon, 18 Mar 2019 09:08:58 -0700 (PDT) MIME-Version: 1.0 References: <56d3373c1c5007d776fcd5de4523f4b9da341fb6.1552679409.git.andreyknvl@google.com> <04c5b2de-7fde-7625-9d42-228160879ea0@gmail.com> In-Reply-To: From: Andrey Konovalov Date: Mon, 18 Mar 2019 17:08:48 +0100 Message-ID: Subject: Re: [PATCH v11 08/14] net, arm64: untag user pointers in tcp_zerocopy_receive To: Eric Dumazet Cc: Eric Dumazet , Catalin Marinas , Will Deacon , Mark Rutland , Robin Murphy , Kees Cook , Kate Stewart , Greg Kroah-Hartman , Andrew Morton , Ingo Molnar , "Kirill A . Shutemov" , Shuah Khan , Vincenzo Frascino , "David S. Miller" , Alexei Starovoitov , Daniel Borkmann , Steven Rostedt , Ingo Molnar , Peter Zijlstra , Arnaldo Carvalho de Melo , Linux ARM , "open list:DOCUMENTATION" , Linux Memory Management List , linux-arch , netdev , bpf , "open list:KERNEL SELFTEST FRAMEWORK" , LKML , Dmitry Vyukov , Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Chintan Pandya , Luc Van Oostenryck , Dave Martin , Kevin Brodsky , Szabolcs Nagy Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Mar 18, 2019 at 3:45 PM Eric Dumazet wrote: > > On Mon, Mar 18, 2019 at 6:17 AM Andrey Konovalov wrote: > > > > > Looking at the code, what's the point of this address != zc->address > > check? Should I just remove it? > > No you must not remove it. > > The test detects if a u64 ->unsigned long conversion might have truncated bits. > > Quite surprisingly some people still use 32bit kernels. > > The ABI is 64bit only, because we did not want to have yet another compat layer. > > struct tcp_zerocopy_receive { > __u64 address; /* in: address of mapping */ > __u32 length; /* in/out: number of bytes to map/mapped */ > __u32 recv_skip_hint; /* out: amount of bytes to skip */ > }; Ah, got it, thanks! I'll add a comment here then, otherwise this looks confusing. From mboxrd@z Thu Jan 1 00:00:00 1970 From: andreyknvl at google.com (Andrey Konovalov) Date: Mon, 18 Mar 2019 17:08:48 +0100 Subject: [PATCH v11 08/14] net, arm64: untag user pointers in tcp_zerocopy_receive In-Reply-To: References: <56d3373c1c5007d776fcd5de4523f4b9da341fb6.1552679409.git.andreyknvl@google.com> <04c5b2de-7fde-7625-9d42-228160879ea0@gmail.com> Message-ID: On Mon, Mar 18, 2019 at 3:45 PM Eric Dumazet wrote: > > On Mon, Mar 18, 2019 at 6:17 AM Andrey Konovalov wrote: > > > > > Looking at the code, what's the point of this address != zc->address > > check? Should I just remove it? > > No you must not remove it. > > The test detects if a u64 ->unsigned long conversion might have truncated bits. > > Quite surprisingly some people still use 32bit kernels. > > The ABI is 64bit only, because we did not want to have yet another compat layer. > > struct tcp_zerocopy_receive { > __u64 address; /* in: address of mapping */ > __u32 length; /* in/out: number of bytes to map/mapped */ > __u32 recv_skip_hint; /* out: amount of bytes to skip */ > }; Ah, got it, thanks! I'll add a comment here then, otherwise this looks confusing. From mboxrd@z Thu Jan 1 00:00:00 1970 From: andreyknvl@google.com (Andrey Konovalov) Date: Mon, 18 Mar 2019 17:08:48 +0100 Subject: [PATCH v11 08/14] net, arm64: untag user pointers in tcp_zerocopy_receive In-Reply-To: References: <56d3373c1c5007d776fcd5de4523f4b9da341fb6.1552679409.git.andreyknvl@google.com> <04c5b2de-7fde-7625-9d42-228160879ea0@gmail.com> Message-ID: Content-Type: text/plain; charset="UTF-8" Message-ID: <20190318160848.QZ0rM8YZOlixav6Ko9v5JcDmNf9p5XxQfQ8s6JLunZI@z> On Mon, Mar 18, 2019@3:45 PM Eric Dumazet wrote: > > On Mon, Mar 18, 2019@6:17 AM Andrey Konovalov wrote: > > > > > Looking at the code, what's the point of this address != zc->address > > check? Should I just remove it? > > No you must not remove it. > > The test detects if a u64 ->unsigned long conversion might have truncated bits. > > Quite surprisingly some people still use 32bit kernels. > > The ABI is 64bit only, because we did not want to have yet another compat layer. > > struct tcp_zerocopy_receive { > __u64 address; /* in: address of mapping */ > __u32 length; /* in/out: number of bytes to map/mapped */ > __u32 recv_skip_hint; /* out: amount of bytes to skip */ > }; Ah, got it, thanks! I'll add a comment here then, otherwise this looks confusing. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrey Konovalov Subject: Re: [PATCH v11 08/14] net, arm64: untag user pointers in tcp_zerocopy_receive Date: Mon, 18 Mar 2019 17:08:48 +0100 Message-ID: References: <56d3373c1c5007d776fcd5de4523f4b9da341fb6.1552679409.git.andreyknvl@google.com> <04c5b2de-7fde-7625-9d42-228160879ea0@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: Sender: netdev-owner@vger.kernel.org To: Eric Dumazet Cc: Eric Dumazet , Catalin Marinas , Will Deacon , Mark Rutland , Robin Murphy , Kees Cook , Kate Stewart , Greg Kroah-Hartman , Andrew Morton , Ingo Molnar , "Kirill A . Shutemov" , Shuah Khan , Vincenzo Frascino , "David S. Miller" , Alexei Starovoitov , Daniel Borkmann , Steven Rostedt , Ingo Molnar , Peter Zijlstra List-Id: linux-arch.vger.kernel.org On Mon, Mar 18, 2019 at 3:45 PM Eric Dumazet wrote: > > On Mon, Mar 18, 2019 at 6:17 AM Andrey Konovalov wrote: > > > > > Looking at the code, what's the point of this address != zc->address > > check? Should I just remove it? > > No you must not remove it. > > The test detects if a u64 ->unsigned long conversion might have truncated bits. > > Quite surprisingly some people still use 32bit kernels. > > The ABI is 64bit only, because we did not want to have yet another compat layer. > > struct tcp_zerocopy_receive { > __u64 address; /* in: address of mapping */ > __u32 length; /* in/out: number of bytes to map/mapped */ > __u32 recv_skip_hint; /* out: amount of bytes to skip */ > }; Ah, got it, thanks! I'll add a comment here then, otherwise this looks confusing. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg1-f196.google.com ([209.85.215.196]:39218 "EHLO mail-pg1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727174AbfCRQJA (ORCPT ); Mon, 18 Mar 2019 12:09:00 -0400 Received: by mail-pg1-f196.google.com with SMTP id h8so11704630pgp.6 for ; Mon, 18 Mar 2019 09:08:59 -0700 (PDT) MIME-Version: 1.0 References: <56d3373c1c5007d776fcd5de4523f4b9da341fb6.1552679409.git.andreyknvl@google.com> <04c5b2de-7fde-7625-9d42-228160879ea0@gmail.com> In-Reply-To: From: Andrey Konovalov Date: Mon, 18 Mar 2019 17:08:48 +0100 Message-ID: Subject: Re: [PATCH v11 08/14] net, arm64: untag user pointers in tcp_zerocopy_receive Content-Type: text/plain; charset="UTF-8" Sender: linux-arch-owner@vger.kernel.org List-ID: To: Eric Dumazet Cc: Eric Dumazet , Catalin Marinas , Will Deacon , Mark Rutland , Robin Murphy , Kees Cook , Kate Stewart , Greg Kroah-Hartman , Andrew Morton , Ingo Molnar , "Kirill A . Shutemov" , Shuah Khan , Vincenzo Frascino , "David S. Miller" , Alexei Starovoitov , Daniel Borkmann , Steven Rostedt , Ingo Molnar , Peter Zijlstra , Arnaldo Carvalho de Melo , Linux ARM , "open list:DOCUMENTATION" , Linux Memory Management List , linux-arch , netdev , bpf , "open list:KERNEL SELFTEST FRAMEWORK" , LKML , Dmitry Vyukov , Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Chintan Pandya , Luc Van Oostenryck , Dave Martin , Kevin Brodsky , Szabolcs Nagy Message-ID: <20190318160848.SfafSNsNexJMXoUxwGnstE8OsHGQBWykvoLp6TZMQns@z> On Mon, Mar 18, 2019 at 3:45 PM Eric Dumazet wrote: > > On Mon, Mar 18, 2019 at 6:17 AM Andrey Konovalov wrote: > > > > > Looking at the code, what's the point of this address != zc->address > > check? Should I just remove it? > > No you must not remove it. > > The test detects if a u64 ->unsigned long conversion might have truncated bits. > > Quite surprisingly some people still use 32bit kernels. > > The ABI is 64bit only, because we did not want to have yet another compat layer. > > struct tcp_zerocopy_receive { > __u64 address; /* in: address of mapping */ > __u32 length; /* in/out: number of bytes to map/mapped */ > __u32 recv_skip_hint; /* out: amount of bytes to skip */ > }; Ah, got it, thanks! I'll add a comment here then, otherwise this looks confusing. 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[209.85.220.65]) by mx.google.com with SMTPS id y4sor1561257pfn.64.2019.03.18.09.08.59 for (Google Transport Security); Mon, 18 Mar 2019 09:08:59 -0700 (PDT) Received-SPF: pass (google.com: domain of andreyknvl@google.com designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20161025 header.b=oxnKC1Tg; spf=pass (google.com: domain of andreyknvl@google.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=andreyknvl@google.com; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=4jnBV7KXAwRH/SBiWunplsgAO5XC9ZDTjIPOKm8iM+g=; b=oxnKC1TgVy0AfRUFzdhntQ4TnaWjo/dHSXwb/USSzN9iByb1J8qb9RNkXwR6mHS+mw U0ldrfn6mRkKtGFn2Svuia32YqyzgHr8lgGpA8Ip0euwMX1zgcj9IEez46oWi1IBddSU gwBvQTSUaqVbn9YXiSr6jTBOA8Xv5UO8CN9pXByf2+OfL6o1mjVRgyqe5P+Xg2G+PiCf NrrQ0yX3K59cnkolhi014Qa1wO07CtueVQk+/0EtrVmsp+hp6aDS9QuNbVuDWXjtk1vJ lpuGAyImKDa6JNaKflwTKUzEOC9JqWe+LJv/B30MBc7OlHCI7rVxIEK1sErhlvMqw4PK B6tw== X-Google-Smtp-Source: APXvYqz4X+86iXGnn3Nho9z6FaNxwbl9pQbIbD8Gz0QIEPwnGUaSMpR4psZ3WXMcGuMVMNFbcG/Runz5qQVKQSjPXF0= X-Received: by 2002:a62:4299:: with SMTP id h25mr19703730pfd.165.1552925338999; Mon, 18 Mar 2019 09:08:58 -0700 (PDT) MIME-Version: 1.0 References: <56d3373c1c5007d776fcd5de4523f4b9da341fb6.1552679409.git.andreyknvl@google.com> <04c5b2de-7fde-7625-9d42-228160879ea0@gmail.com> In-Reply-To: From: Andrey Konovalov Date: Mon, 18 Mar 2019 17:08:48 +0100 Message-ID: Subject: Re: [PATCH v11 08/14] net, arm64: untag user pointers in tcp_zerocopy_receive To: Eric Dumazet Cc: Eric Dumazet , Catalin Marinas , Will Deacon , Mark Rutland , Robin Murphy , Kees Cook , Kate Stewart , Greg Kroah-Hartman , Andrew Morton , Ingo Molnar , "Kirill A . Shutemov" , Shuah Khan , Vincenzo Frascino , "David S. Miller" , Alexei Starovoitov , Daniel Borkmann , Steven Rostedt , Ingo Molnar , Peter Zijlstra , Arnaldo Carvalho de Melo , Linux ARM , "open list:DOCUMENTATION" , Linux Memory Management List , linux-arch , netdev , bpf , "open list:KERNEL SELFTEST FRAMEWORK" , LKML , Dmitry Vyukov , Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Chintan Pandya , Luc Van Oostenryck , Dave Martin , Kevin Brodsky , Szabolcs Nagy Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Mar 18, 2019 at 3:45 PM Eric Dumazet wrote: > > On Mon, Mar 18, 2019 at 6:17 AM Andrey Konovalov wrote: > > > > > Looking at the code, what's the point of this address != zc->address > > check? Should I just remove it? > > No you must not remove it. > > The test detects if a u64 ->unsigned long conversion might have truncated bits. > > Quite surprisingly some people still use 32bit kernels. > > The ABI is 64bit only, because we did not want to have yet another compat layer. > > struct tcp_zerocopy_receive { > __u64 address; /* in: address of mapping */ > __u32 length; /* in/out: number of bytes to map/mapped */ > __u32 recv_skip_hint; /* out: amount of bytes to skip */ > }; Ah, got it, thanks! I'll add a comment here then, otherwise this looks confusing. 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a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=4jnBV7KXAwRH/SBiWunplsgAO5XC9ZDTjIPOKm8iM+g=; b=EKxkSj4Py2G0FYhANms0Bx1O0KLf+scrJUNV+Hfv13rpQfnGApGbtyx+wsy/7CcEAD pRWtvi5tCWqIk4TlQ3SEqtu+gpplss8iwn3cK7PjlmEQODnyT0qzp9rBuFfADdyBr+CF nr5nZ6Vu0ZmrKBDe5Lg0dqlUQNgKQoIXrhRk6O1/NEClAlbY7c+QaqjWVT3N5tydsTEG w98BSLzM8SGD9UNfRR4wuSr4V5Kt2p8Rp/fiFydo5PrQpcDqYr3NACKmukIY+Y6r6Lwn JdvItVhtkOIlQf4pW5dQKQvF80sbgaWjpLPTOSfdRgkmrU7T7+Lt3xWfmOIYL/SAvRXd 496g== X-Gm-Message-State: APjAAAX6DqeTjzmKPz+jIdafwsoi3QQK8CnJ4Y80AVs20yhWq3tXc/y6 eFFJoOLmotdsGtL8tIhvhnwzxbSAJQ/bvl6uUqwOgw== X-Google-Smtp-Source: APXvYqz4X+86iXGnn3Nho9z6FaNxwbl9pQbIbD8Gz0QIEPwnGUaSMpR4psZ3WXMcGuMVMNFbcG/Runz5qQVKQSjPXF0= X-Received: by 2002:a62:4299:: with SMTP id h25mr19703730pfd.165.1552925338999; Mon, 18 Mar 2019 09:08:58 -0700 (PDT) MIME-Version: 1.0 References: <56d3373c1c5007d776fcd5de4523f4b9da341fb6.1552679409.git.andreyknvl@google.com> <04c5b2de-7fde-7625-9d42-228160879ea0@gmail.com> In-Reply-To: From: Andrey Konovalov Date: Mon, 18 Mar 2019 17:08:48 +0100 Message-ID: Subject: Re: [PATCH v11 08/14] net, arm64: untag user pointers in tcp_zerocopy_receive To: Eric Dumazet X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190318_090901_205502_A73FCFF6 X-CRM114-Status: GOOD ( 14.09 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Kate Stewart , "open list:DOCUMENTATION" , Peter Zijlstra , Catalin Marinas , Will Deacon , Alexei Starovoitov , Linux Memory Management List , "open list:KERNEL SELFTEST FRAMEWORK" , Chintan Pandya , Vincenzo Frascino , Shuah Khan , Ingo Molnar , linux-arch , Jacob Bramley , Daniel Borkmann , Szabolcs Nagy , Ingo Molnar , Dmitry Vyukov , Ramana Radhakrishnan , Dave Martin , Evgeniy Stepanov , Kevin Brodsky , Kees Cook , Ruben Ayrapetyan , Lee Smith , Steven Rostedt , Arnaldo Carvalho de Melo , bpf , Linux ARM , Eric Dumazet , Kostya Serebryany , Greg Kroah-Hartman , LKML , Luc Van Oostenryck , netdev , Andrew Morton , Robin Murphy , "David S. Miller" , "Kirill A . Shutemov" Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Mar 18, 2019 at 3:45 PM Eric Dumazet wrote: > > On Mon, Mar 18, 2019 at 6:17 AM Andrey Konovalov wrote: > > > > > Looking at the code, what's the point of this address != zc->address > > check? Should I just remove it? > > No you must not remove it. > > The test detects if a u64 ->unsigned long conversion might have truncated bits. > > Quite surprisingly some people still use 32bit kernels. > > The ABI is 64bit only, because we did not want to have yet another compat layer. > > struct tcp_zerocopy_receive { > __u64 address; /* in: address of mapping */ > __u32 length; /* in/out: number of bytes to map/mapped */ > __u32 recv_skip_hint; /* out: amount of bytes to skip */ > }; Ah, got it, thanks! I'll add a comment here then, otherwise this looks confusing. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel