From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.zytor.com (terminus.zytor.com [198.137.202.136]) (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 8BA2C3F880D; Wed, 25 Mar 2026 16:30:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.136 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774456254; cv=none; b=f0AgBNUiEpmxXbZIcYak92bxoKPVlBQOCd2FM46PjqQnIcu6//eFfHxWGW6qSWSL+sN6v0ka1ZpgOp9QyxFGti9o4hDMvmGaRbgutpuD76QfGahvUH/cKDYCNkMjpiihXvkLQR3ljqTaAHR2cFdl5scnbFne6aCspqw8QWSJkDs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774456254; c=relaxed/simple; bh=+AmS+tOzD2cSA2LrII2fvtTfr6fN6xggErI+us8oNsU=; h=Message-ID:Date:MIME-Version:Subject:From:To:Cc:References: In-Reply-To:Content-Type; b=LJsu54Hl9HwsWmnks0SA600+IghioZhBaylQZ7O86RicIwNyxA2Gmy6SRaJYJVB2gqY49GtJSyhsVCCidVTv5z8WDz6hGx6eVzBhDkFhpXL6SNP8pj02Cyzn039NNiiBRkBZMJPLT5u5lvvw6+kIXk0XeVZzKSjW9yUlwXP6qXk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zytor.com; spf=pass smtp.mailfrom=zytor.com; dkim=pass (2048-bit key) header.d=zytor.com header.i=@zytor.com header.b=J5ymzmT6; arc=none smtp.client-ip=198.137.202.136 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zytor.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=zytor.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=zytor.com header.i=@zytor.com header.b="J5ymzmT6" Received: from [IPV6:2601:646:8081:9481:619:3ffd:957c:6748] ([IPv6:2601:646:8081:9481:619:3ffd:957c:6748]) (authenticated bits=0) by mail.zytor.com (8.18.1/8.17.1) with ESMTPSA id 62PGDMNL3153560 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NO); Wed, 25 Mar 2026 09:13:22 -0700 DKIM-Filter: OpenDKIM Filter v2.11.0 mail.zytor.com 62PGDMNL3153560 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zytor.com; s=2026022301; t=1774455208; bh=v2u7ExN5eifBevZeC2xb3xyOceea1RmqMBZtOrcYzMg=; h=Date:Subject:From:To:Cc:References:In-Reply-To:From; b=J5ymzmT6BQR65DUAALhhSYjcHADheoqS/Y1TB20cnYBvtYJoCBoHEmdHJLu/Si20r 6rz3J3dMJE/DEAiYOO3Fx6vfsrD2MnYD1ixgvwprxcGhIEVWzMLmCHreu1sLIn5SNP 6VBBW2+SCSgr4uOYIIcCe+9jSspVTz7NsGduU1IHGnQyH3sgnggWaXIAuTY0sSScDJ hy7fCQlaHvFN3juiyk0mVo/l0cAc4F3B4clshklYM45be69gwY6re6ju8/GDKmI3HX ln5NoZUdBqzuxxOWGyGyQysV8OXGXSO4zB7ByDmwCtm51dOIhtQh0z8KO6LEy/vgUL bF7T6QJ+oA0WA== Message-ID: Date: Wed, 25 Mar 2026 09:13:16 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 02/17] raid6: remove __KERNEL__ ifdefs From: "H. Peter Anvin" To: Christoph Hellwig , Andrew Morton Cc: Catalin Marinas , Will Deacon , Ard Biesheuvel , Huacai Chen , WANG Xuerui , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , "Christophe Leroy (CS GROUP)" , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Herbert Xu , Dan Williams , Chris Mason , David Sterba , Arnd Bergmann , Song Liu , Yu Kuai , Li Nan , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, loongarch@lists.linux.dev, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-crypto@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-arch@vger.kernel.org, linux-raid@vger.kernel.org References: <20260324064115.3217136-1-hch@lst.de> <20260324064115.3217136-3-hch@lst.de> <59d1d178-c141-4229-81e9-a6c23fa81f2f@zytor.com> Content-Language: en-US, sv-SE In-Reply-To: <59d1d178-c141-4229-81e9-a6c23fa81f2f@zytor.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 2026-03-25 08:13, H. Peter Anvin wrote: > On 2026-03-23 23:40, Christoph Hellwig wrote: >> With the test code ported to kernel space, none of this is required. > > I really *really* don't like this. > > The ability of running in user space is really useful when it comes to > developing new code for new platforms, which happens often enough for this code. > That being said -- and I do say this as the original author of this code -- this should be reduced to the maximum extent possible to a (minimal) set of #ifndef __KERNEL__, which should be localized as much as possible. The actual user space components, even such a thing as a simple #include, should be moved to a separate user space header. But pretty please do leave the ability to debug the algorithms in user space. This is hard code to write and debug; it is not just about regression testing. -hpa