From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f42.google.com (mail-pj1-f42.google.com [209.85.216.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 454BE36120 for ; Fri, 9 Feb 2024 23:20:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.42 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707520845; cv=none; b=p6776rlscd5PPxUnuOQUZ9ikIEIJh1O45EacThWYNbI1pimGpQnzb/ObXRQjEMPP9Cr4XPPVNfcEjyFgbL3otoK08HHyinEcGWmtKJ87sUilsIC6llAr9pslgbNUsBfcVxHM7P6d9t7gtGaR3mG+8KMtmEe8pBnKnUj2mNF6kNw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707520845; c=relaxed/simple; bh=uf75RmmaasfJs85RE/vtD2MDKZCAkQJrySp0Fe5u+Lc=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=nX1qWk/6M6D+0O+6BTQGqtGy20rSmuTPAkaphkuCgQhjjUo3RvTHrlUTG7hIa+Fg4BzbGaWxF1AOrsTYoy4+AycQ5NIhBon/cqrBfuJdTGsW6570En2B07hmMokghdF3zj6y3KPWm0ChgJsN1gWR975kVIeKbZweKO0XxvIZhM8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=roeck-us.net; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=cN85CGzV; arc=none smtp.client-ip=209.85.216.42 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=roeck-us.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="cN85CGzV" Received: by mail-pj1-f42.google.com with SMTP id 98e67ed59e1d1-2970f940b7cso550623a91.2 for ; Fri, 09 Feb 2024 15:20:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1707520842; x=1708125642; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:autocrypt:from:references:cc :to:content-language:subject:user-agent:mime-version:date:message-id :sender:from:to:cc:subject:date:message-id:reply-to; bh=pUX7rZnvyFvDNPjdlReFBmCCuHj67RGrGqzMayPKgZI=; b=cN85CGzV/8L9ObKB+yKGIAt3V4ZJrpyCNoUfkf1mSrLI+SlUtEn/XGKs/udlb3MQZU E2sr9GtMGKWwy7SB/67H/jVfqvLLBMfpZbfENV6KBLWA2hnOdnOV9b9+lZDnn5czoW+S zGGhxO76YqnPRRhLKNex48qcusq+Z8zIFtQfUENHPLt4pH+EOzdn/7yTrIZt0asf8kzZ eELFsBSGLJcK+32GR9WEbAbasiFys1Abj3jMWh+ulL1MBnLQzo2KsDxTBSntWbm736lM Uv/sWkwPRqRQAHnL6M3MnCUz66zMo56IjVEbn9+mN4sLDvUpNr4mukRO620GmPpoNnH7 ncgg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1707520842; x=1708125642; h=content-transfer-encoding:in-reply-to:autocrypt:from:references:cc :to:content-language:subject:user-agent:mime-version:date:message-id :sender:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=pUX7rZnvyFvDNPjdlReFBmCCuHj67RGrGqzMayPKgZI=; b=slqCkLZ3ScKhwghVOrGWE/Wc5Y7QFmbzmUf+GMVdRU8pVn8W5YN570VJ/24GWX9Ii9 QNs8NJQUVwZYlsC0HciDpy53nX8z9Xqa652mNhBCQ6NqqcjsqKeaacsgalFNztsIqB2O zs+pVLsLpGJ64HQtQ4PiCFCPkF6MuUFBdIvLV08eesjCOVkG/KF8GsOX+hjMVW8MbJ9o g4BFT5Ms7H9yz6Q24slog1XSsXJG0foH0jdw9ODaMbUZmuaJJa9sGqzQtPCZPuGM4Mow 6yrebScTolYnH291t/BYv3ARcg9XfCtcjnY+4o9G8F55DDyrsOmq/9w7ya1FM2Sl88LU 7xWg== X-Gm-Message-State: AOJu0Yz1vupFTs2KNwM2bssqiBfOqwEap+smmWqT6HDa9TFy8IQcD6Ys 5FhgjD4hsp0SJRwmfjGfIcMt2Ko/iUgWk6f+8fgic8PPvS79/zbSeUTIKTL5 X-Google-Smtp-Source: AGHT+IGUsY5Q2E7R5Anl9qHZBwl21KIW3GdFPbhJ5W+fDcaCtamSmi8icEAHwM6sO8DraOi2XdhNNg== X-Received: by 2002:a17:90b:380e:b0:296:43a:932e with SMTP id mq14-20020a17090b380e00b00296043a932emr598534pjb.7.1707520842505; Fri, 09 Feb 2024 15:20:42 -0800 (PST) Received: from ?IPV6:2600:1700:e321:62f0:329c:23ff:fee3:9d7c? ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id fr21-20020a17090ae2d500b00296bb0b2f57sm2355152pjb.21.2024.02.09.15.20.41 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 09 Feb 2024 15:20:41 -0800 (PST) Sender: Guenter Roeck Message-ID: Date: Fri, 9 Feb 2024 15:20:40 -0800 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 v2] regmap: kunit: Ensure that changed bytes are actually different Content-Language: en-US To: Mark Brown Cc: linux-kernel@vger.kernel.org References: <20240209-regmap-kunit-random-change-v2-1-be0a447c2891@kernel.org> <7d077da1-e792-4570-914e-5c26de420c43@roeck-us.net> From: Guenter Roeck Autocrypt: addr=linux@roeck-us.net; keydata= xsFNBE6H1WcBEACu6jIcw5kZ5dGeJ7E7B2uweQR/4FGxH10/H1O1+ApmcQ9i87XdZQiB9cpN RYHA7RCEK2dh6dDccykQk3bC90xXMPg+O3R+C/SkwcnUak1UZaeK/SwQbq/t0tkMzYDRxfJ7 nyFiKxUehbNF3r9qlJgPqONwX5vJy4/GvDHdddSCxV41P/ejsZ8PykxyJs98UWhF54tGRWFl 7i1xvaDB9lN5WTLRKSO7wICuLiSz5WZHXMkyF4d+/O5ll7yz/o/JxK5vO/sduYDIlFTvBZDh gzaEtNf5tQjsjG4io8E0Yq0ViobLkS2RTNZT8ICq/Jmvl0SpbHRvYwa2DhNsK0YjHFQBB0FX IdhdUEzNefcNcYvqigJpdICoP2e4yJSyflHFO4dr0OrdnGLe1Zi/8Xo/2+M1dSSEt196rXaC kwu2KgIgmkRBb3cp2vIBBIIowU8W3qC1+w+RdMUrZxKGWJ3juwcgveJlzMpMZNyM1jobSXZ0 VHGMNJ3MwXlrEFPXaYJgibcg6brM6wGfX/LBvc/haWw4yO24lT5eitm4UBdIy9pKkKmHHh7s jfZJkB5fWKVdoCv/omy6UyH6ykLOPFugl+hVL2Prf8xrXuZe1CMS7ID9Lc8FaL1ROIN/W8Vk BIsJMaWOhks//7d92Uf3EArDlDShwR2+D+AMon8NULuLBHiEUQARAQABzTJHdWVudGVyIFJv ZWNrIChMaW51eCBhY2NvdW50KSA8bGludXhAcm9lY2stdXMubmV0PsLBgQQTAQIAKwIbAwYL CQgHAwIGFQgCCQoLBBYCAwECHgECF4ACGQEFAlVcphcFCRmg06EACgkQyx8mb86fmYFg0RAA nzXJzuPkLJaOmSIzPAqqnutACchT/meCOgMEpS5oLf6xn5ySZkl23OxuhpMZTVX+49c9pvBx hpvl5bCWFu5qC1jC2eWRYU+aZZE4sxMaAGeWenQJsiG9lP8wkfCJP3ockNu0ZXXAXwIbY1O1 c+l11zQkZw89zNgWgKobKzrDMBFOYtAh0pAInZ9TSn7oA4Ctejouo5wUugmk8MrDtUVXmEA9 7f9fgKYSwl/H7dfKKsS1bDOpyJlqhEAH94BHJdK/b1tzwJCFAXFhMlmlbYEk8kWjcxQgDWMu GAthQzSuAyhqyZwFcOlMCNbAcTSQawSo3B9yM9mHJne5RrAbVz4TWLnEaX8gA5xK3uCNCeyI sqYuzA4OzcMwnnTASvzsGZoYHTFP3DQwf2nzxD6yBGCfwNGIYfS0i8YN8XcBgEcDFMWpOQhT Pu3HeztMnF3HXrc0t7e5rDW9zCh3k2PA6D2NV4fews9KDFhLlTfCVzf0PS1dRVVWM+4jVl6l HRIAgWp+2/f8dx5vPc4Ycp4IsZN0l1h9uT7qm1KTwz+sSl1zOqKD/BpfGNZfLRRxrXthvvY8 BltcuZ4+PGFTcRkMytUbMDFMF9Cjd2W9dXD35PEtvj8wnEyzIos8bbgtLrGTv/SYhmPpahJA l8hPhYvmAvpOmusUUyB30StsHIU2LLccUPPOwU0ETofVZwEQALlLbQeBDTDbwQYrj0gbx3bq 7kpKABxN2MqeuqGr02DpS9883d/t7ontxasXoEz2GTioevvRmllJlPQERVxM8gQoNg22twF7 pB/zsrIjxkE9heE4wYfN1AyzT+AxgYN6f8hVQ7Nrc9XgZZe+8IkuW/Nf64KzNJXnSH4u6nJM J2+Dt274YoFcXR1nG76Q259mKwzbCukKbd6piL+VsT/qBrLhZe9Ivbjq5WMdkQKnP7gYKCAi pNVJC4enWfivZsYupMd9qn7Uv/oCZDYoBTdMSBUblaLMwlcjnPpOYK5rfHvC4opxl+P/Vzyz 6WC2TLkPtKvYvXmdsI6rnEI4Uucg0Au/Ulg7aqqKhzGPIbVaL+U0Wk82nz6hz+WP2ggTrY1w ZlPlRt8WM9w6WfLf2j+PuGklj37m+KvaOEfLsF1v464dSpy1tQVHhhp8LFTxh/6RWkRIR2uF I4v3Xu/k5D0LhaZHpQ4C+xKsQxpTGuYh2tnRaRL14YMW1dlI3HfeB2gj7Yc8XdHh9vkpPyuT nY/ZsFbnvBtiw7GchKKri2gDhRb2QNNDyBnQn5mRFw7CyuFclAksOdV/sdpQnYlYcRQWOUGY HhQ5eqTRZjm9z+qQe/T0HQpmiPTqQcIaG/edgKVTUjITfA7AJMKLQHgp04Vylb+G6jocnQQX JqvvP09whbqrABEBAAHCwWUEGAECAA8CGwwFAlVcpi8FCRmg08MACgkQyx8mb86fmYHNRQ/+ J0OZsBYP4leJvQF8lx9zif+v4ZY/6C9tTcUv/KNAE5leyrD4IKbnV4PnbrVhjq861it/zRQW cFpWQszZyWRwNPWUUz7ejmm9lAwPbr8xWT4qMSA43VKQ7ZCeTQJ4TC8kjqtcbw41SjkjrcTG wF52zFO4bOWyovVAPncvV9eGA/vtnd3xEZXQiSt91kBSqK28yjxAqK/c3G6i7IX2rg6pzgqh hiH3/1qM2M/LSuqAv0Rwrt/k+pZXE+B4Ud42hwmMr0TfhNxG+X7YKvjKC+SjPjqp0CaztQ0H nsDLSLElVROxCd9m8CAUuHplgmR3seYCOrT4jriMFBtKNPtj2EE4DNV4s7k0Zy+6iRQ8G8ng QjsSqYJx8iAR8JRB7Gm2rQOMv8lSRdjva++GT0VLXtHULdlzg8VjDnFZ3lfz5PWEOeIMk7Rj trjv82EZtrhLuLjHRCaG50OOm0hwPSk1J64R8O3HjSLdertmw7eyAYOo4RuWJguYMg5DRnBk WkRwrSuCn7UG+qVWZeKEsFKFOkynOs3pVbcbq1pxbhk3TRWCGRU5JolI4ohy/7JV1TVbjiDI HP/aVnm6NC8of26P40Pg8EdAhajZnHHjA7FrJXsy3cyIGqvg9os4rNkUWmrCfLLsZDHD8FnU mDW4+i+XlNFUPUYMrIKi9joBhu18ssf5i5Q= In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 2/9/24 14:39, Mark Brown wrote: > On Fri, Feb 09, 2024 at 02:07:38PM -0800, Guenter Roeck wrote: > >> This is actually worse than v1 because hw_buf[6] isn't used anywhere. >> Making sure that the values in the val[] array don't match the values >> in hw_buf[6..7] doesn't add any value. > > Yeah, I realised after reading your earlier mail. It's passing for me > somehow. > It is passing because the probability for it to fail is really low. It only fails reliably with the cheat below. >> FWIW, I had struggled with the re-use of val[0] for two different tests >> (on hw_buf[2] and hw_buf[4]) myself. The only solution other than making sure >> that it neither matches hw_buf[2] nor hw_buf[4] I came up with was to use a >> separate variable for the accesses to hw_buf[4] (or hw_buf[6] in the old code). > Indeed, it was fine with the old code due to not caring about having > different values but we need to generate three values now. > >> get_changed_bytes(&hw_buf[6], &val[0], sizeof(val)); >> + // Let's cheat. >> + // Remember, the above code doesn't look into hw_buf[2..5], >> + // so anything might be in there, including the values from >> + // the val[] array. >> + hw_buf[2] = val[0]; >> + hw_buf[3] = val[1]; >> + hw_buf[4] = val[0]; >> + hw_buf[5] = val[1]; > > I don't understand how this interacts with the pre-sync check? That is because the test expects the memory in hw_buf[] and val[] to be different (because hw_buf[] wasn't updated to the new values). The above cheat forces hw_buf[2,3] and val[0,1] to be the same, so the pre-sync test fails. The post-sync test passes because the values are expected to be the same at that time. Guenter