From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 F06BD1A7264; Mon, 24 Aug 2026 12:17:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787573835; cv=none; b=lHzLnit+azQeSRP0C2KXyjW0oa5JuZJp7E6e1HeNIL37/u9/BR7CkqdLhOxLxqDMn17P2p9x3TtBv4qigHao54HmPI/EmEjDVSFHB3s4+br8yehROTJTC/MmIYvTOBfwaB7lcWgZct55uD2x4+ngqPBIpjAD1sHp+9XKCRezY2c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787573835; c=relaxed/simple; bh=5dpYqYzR5hpkg2iQBtqh8qx/SDXcXWfDGbxoyeWxE3w=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=cL3RJg3kh6Gh6CQrDBBAaQtFQ8PugVtxOaPfFnVQvPDjVBL7AEhSo7MwwMedi44GG+WlVXwW+h4NUUa+bi8C70ohdhtQhRc/+BsOPZ+03nuuomxcb9+OoNJIuUOtOfX6Lj2S9dVUr+lRyEoqxT/8wnNOAkfKdB1SZ1AxikGaQXA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=mW/hFf5G; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="mW/hFf5G" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 594591F00A3A; Mon, 24 Aug 2026 12:17:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787573833; bh=I9G+2pR4S+ko3JJWwpOLkXez1wvJqD3jZzDSrEX5v8M=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=mW/hFf5GQRaQ9wugKNZZrfdTcCRiHg95Gg5mArsWXJg+ZyTkK1fCiQsevUocW2+kk w98u41xT9vSlJ0tnn1GnY7HZ9rQMESvfWKfMHZFr2LUkwz+v+XlYn+i1IpUrCldS0I g8ZKkihlumtUH2TQjqznlLAWOtes98bfAzxMX5LJiM0nxrBsEtd3PGnUl6jXOY0bdv q6aPdnkeO+vy3Bjw89c0oDIUApCOi4iirPuNPSsJuUuAQlh6l2gD6aQQZ2nvBdHsiz fjrYFbh5HPIcvsh62m8kCUvV9SvJ07ajA/FfsKfP52LBp+M8G/CBgjkiXUNIg7KmG6 skGXj7cd6v4Ug== Message-ID: <75738049-24f9-4056-98c8-b4075552ab78@kernel.org> Date: Mon, 24 Aug 2026 14:17:03 +0200 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 v7 1/6] selftests/mm: make file helpers return errors To: Sarthak Sharma , Andrew Morton Cc: Lorenzo Stoakes , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Shuah Khan , Zi Yan , Baolin Wang , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Jason Gunthorpe , John Hubbard , Peter Xu , Leon Romanovsky , Jonathan Corbet , Shuah Khan , Mark Brown , Anshuman Khandual , linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org References: <20260813181230.483746-1-sarthak.sharma@arm.com> <20260813181230.483746-2-sarthak.sharma@arm.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzS5EYXZpZCBIaWxk ZW5icmFuZCAoQ3VycmVudCkgPGRhdmlkQGtlcm5lbC5vcmc+wsGQBBMBCAA6AhsDBQkmWAik AgsJBBUKCQgCFgICHgUCF4AWIQQb2cqtc1xMOkYN/MpN3hD3AP+DWgUCaYJt/AIZAQAKCRBN 3hD3AP+DWriiD/9BLGEKG+N8L2AXhikJg6YmXom9ytRwPqDgpHpVg2xdhopoWdMRXjzOrIKD g4LSnFaKneQD0hZhoArEeamG5tyo32xoRsPwkbpIzL0OKSZ8G6mVbFGpjmyDLQCAxteXCLXz ZI0VbsuJKelYnKcXWOIndOrNRvE5eoOfTt2XfBnAapxMYY2IsV+qaUXlO63GgfIOg8RBaj7x 3NxkI3rV0SHhI4GU9K6jCvGghxeS1QX6L/XI9mfAYaIwGy5B68kF26piAVYv/QZDEVIpo3t7 /fjSpxKT8plJH6rhhR0epy8dWRHk3qT5tk2P85twasdloWtkMZ7FsCJRKWscm1BLpsDn6EQ4 jeMHECiY9kGKKi8dQpv3FRyo2QApZ49NNDbwcR0ZndK0XFo15iH708H5Qja/8TuXCwnPWAcJ DQoNIDFyaxe26Rx3ZwUkRALa3iPcVjE0//TrQ4KnFf+lMBSrS33xDDBfevW9+Dk6IISmDH1R HFq2jpkN+FX/PE8eVhV68B2DsAPZ5rUwyCKUXPTJ/irrCCmAAb5Jpv11S7hUSpqtM/6oVESC 3z/7CzrVtRODzLtNgV4r5EI+wAv/3PgJLlMwgJM90Fb3CB2IgbxhjvmB1WNdvXACVydx55V7 LPPKodSTF29rlnQAf9HLgCphuuSrrPn5VQDaYZl4N/7zc2wcWM7BTQRVy5+RARAA59fefSDR 9nMGCb9LbMX+TFAoIQo/wgP5XPyzLYakO+94GrgfZjfhdaxPXMsl2+o8jhp/hlIzG56taNdt VZtPp3ih1AgbR8rHgXw1xwOpuAd5lE1qNd54ndHuADO9a9A0vPimIes78Hi1/yy+ZEEvRkHk /kDa6F3AtTc1m4rbbOk2fiKzzsE9YXweFjQvl9p+AMw6qd/iC4lUk9g0+FQXNdRs+o4o6Qvy iOQJfGQ4UcBuOy1IrkJrd8qq5jet1fcM2j4QvsW8CLDWZS1L7kZ5gT5EycMKxUWb8LuRjxzZ 3QY1aQH2kkzn6acigU3HLtgFyV1gBNV44ehjgvJpRY2cC8VhanTx0dZ9mj1YKIky5N+C0f21 zvntBqcxV0+3p8MrxRRcgEtDZNav+xAoT3G0W4SahAaUTWXpsZoOecwtxi74CyneQNPTDjNg azHmvpdBVEfj7k3p4dmJp5i0U66Onmf6mMFpArvBRSMOKU9DlAzMi4IvhiNWjKVaIE2Se9BY FdKVAJaZq85P2y20ZBd08ILnKcj7XKZkLU5FkoA0udEBvQ0f9QLNyyy3DZMCQWcwRuj1m73D sq8DEFBdZ5eEkj1dCyx+t/ga6x2rHyc8Sl86oK1tvAkwBNsfKou3v+jP/l14a7DGBvrmlYjO 59o3t6inu6H7pt7OL6u6BQj7DoMAEQEAAcLBfAQYAQgAJgIbDBYhBBvZyq1zXEw6Rg38yk3e EPcA/4NaBQJonNqrBQkmWAihAAoJEE3eEPcA/4NaKtMQALAJ8PzprBEXbXcEXwDKQu+P/vts IfUb1UNMfMV76BicGa5NCZnJNQASDP/+bFg6O3gx5NbhHHPeaWz/VxlOmYHokHodOvtL0WCC 8A5PEP8tOk6029Z+J+xUcMrJClNVFpzVvOpb1lCbhjwAV465Hy+NUSbbUiRxdzNQtLtgZzOV Zw7jxUCs4UUZLQTCuBpFgb15bBxYZ/BL9MbzxPxvfUQIPbnzQMcqtpUs21CMK2PdfCh5c4gS sDci6D5/ZIBw94UQWmGpM/O1ilGXde2ZzzGYl64glmccD8e87OnEgKnH3FbnJnT4iJchtSvx yJNi1+t0+qDti4m88+/9IuPqCKb6Stl+s2dnLtJNrjXBGJtsQG/sRpqsJz5x1/2nPJSRMsx9 5YfqbdrJSOFXDzZ8/r82HgQEtUvlSXNaXCa95ez0UkOG7+bDm2b3s0XahBQeLVCH0mw3RAQg r7xDAYKIrAwfHHmMTnBQDPJwVqxJjVNr7yBic4yfzVWGCGNE4DnOW0vcIeoyhy9vnIa3w1uZ 3iyY2Nsd7JxfKu1PRhCGwXzRw5TlfEsoRI7V9A8isUCoqE2Dzh3FvYHVeX4Us+bRL/oqareJ CIFqgYMyvHj7Q06kTKmauOe4Nf0l0qEkIuIzfoLJ3qr5UyXc2hLtWyT9Ir+lYlX9efqh7mOY qIws/H2t In-Reply-To: <20260813181230.483746-2-sarthak.sharma@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/13/26 20:12, Sarthak Sharma wrote: > Change read_file(), write_file(), read_num(), write_num() and > write_num_ignore_einval() in vm_util.c to report failures to callers > instead of exiting from the helper. > > Make read_file() return a negative errno on failure and 0 on success, so > callers can distinguish a successful read from an I/O error. Also make > read_num() reject negative and malformed values. > > Keep write_num_ignore_einval() silent for -EINVAL while returning other > errors to its caller. > > Update callers to print diagnostics and fail wherever required. Also add > a helper print_file_access_error() in hugepage_settings.c to print > TAP-compatible errors without a kselftest dependency. This prepares the > helpers to be moved to tools/lib/mm without a kselftest dependency. > > Signed-off-by: Sarthak Sharma > --- [...] > -unsigned long read_num(const char *path) > +int read_num(const char *path, unsigned long *num) > { > + unsigned long val; > + int ret; > char buf[21]; > + char *end; > > - if (!read_file(path, buf, sizeof(buf))) > - ksft_exit_fail_perror("read_file()"); > + if (!num) > + return -EINVAL; > > - return strtoul(buf, NULL, 10); > + ret = read_file(path, buf, sizeof(buf)); > + if (ret) > + return ret; > + > + if (buf[0] < '0' || buf[0] > '9') > + return -EINVAL; This is to reject any negative or hexadecimal numbers I assume? (essentially anything that's not a valid number) Worth adding a comment. Apart from that LGTM Acked-by: David Hildenbrand (Arm) -- Cheers, David