From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.kundenserver.de (mout.kundenserver.de [212.227.126.134]) by sourceware.org (Postfix) with ESMTPS id 22FC63858D35 for ; Fri, 10 Dec 2021 11:23:40 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 22FC63858D35 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=arndb.de Authentication-Results: sourceware.org; spf=none smtp.mailfrom=arndb.de Received: from mail-wr1-f51.google.com ([209.85.221.51]) by mrelayeu.kundenserver.de (mreue011 [213.165.67.97]) with ESMTPSA (Nemesis) id 1MGiF0-1mhqTg2Evy-00DobR for ; Fri, 10 Dec 2021 12:23:38 +0100 Received: by mail-wr1-f51.google.com with SMTP id d24so14488385wra.0 for ; Fri, 10 Dec 2021 03:23:37 -0800 (PST) X-Gm-Message-State: AOAM533HTtrOFOWr2Y6kn2WC1xotD7mY2QPZanWb50hf7j6rpo7YCoyz hL1VpT98OtSYKQeAy70PW1CP6KTAUDiSkQcRvaE= X-Google-Smtp-Source: ABdhPJyiE+xR0mc0B0ZKWS5oiinLRrHnY/UD0db+afyZZWjrpYA75jFicohiRQdcdN9KHIgy+0NzC71sfunlpWLxxP8= X-Received: by 2002:a5d:64ea:: with SMTP id g10mr13391585wri.137.1639135417583; Fri, 10 Dec 2021 03:23:37 -0800 (PST) MIME-Version: 1.0 References: <20211209191048.4031643-1-adhemerval.zanella@linaro.org> <87r1alegcp.fsf@oldenburg.str.redhat.com> <6ab62b15-6982-0786-3b61-b27c058c4475@linaro.org> In-Reply-To: <6ab62b15-6982-0786-3b61-b27c058c4475@linaro.org> From: Arnd Bergmann Date: Fri, 10 Dec 2021 12:23:21 +0100 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] linux: Use 'long int' for timespec tv_nsec on x32 (BZ #16437) To: Adhemerval Zanella Cc: Florian Weimer , Adhemerval Zanella via Libc-alpha , Zack Weinberg Content-Type: text/plain; charset="UTF-8" X-Provags-ID: V03:K1:0IS3UqyApa6kqKkRGIxDDdMPIarxwUbR7FMnpkHDRi3Cz9Dd1Fw hvOTlQfZCGu4AnZXx/nbcesy3Qej/D92+Voho6u6rhIkbe/kpp8bdWsddzh07zupnYElE9L xvuN4FnQRsUPwfeZdQkrYFygzlQN75yPyhUb5VkfhVB3eXBPmKgGuhzJZIGWfmY3hXAkvec Dx81k5LFqn996FA06TlCA== X-UI-Out-Filterresults: notjunk:1;V03:K0:ZAWUwNVrrCY=:FA8jtTSimRwxr8ee0ZU3X3 YRPVOYZHInz55Nxt8SpAR+57i2S6qiYb8doTbx9DQh8gBEGc5/0K66joeCmSApHzmxLh95YAQ sJFH/33ucQP04dozqytqKZPjtPvdAwGwATP+XFpROI5k/L6Obii0rnGrF6roKpZFhMFW+dDx4 hkqAHXNkdu3rP198SXM3rwWTDuA6z3mMU1sugNR13T0+mXzbEMngycILsE4tZWAcQpZtcW9Ad uhmueilUeclRTxy8oAshg6o2cghuZnb3D+UCtYxAJG18PeTtnnXwe2ijG8SvuVMhKMEUuku2s 89QVRlVZl7CWpQGewjOdE5CGlymK4RXCS85h/6gzFcjgleJiAAxbc0CQ/p5IG0E7iu5fEd2Oz QkjxCA01Lg0eCv/YkRd7FTXPkC3XW+WUc4AXlhRGtfw25eNrveIj6rY5uEMRhVlOmnP+jdt13 yq/iWYVjeAIBUpA6jhm+OVLQFi222eS0IJs6Hc12vKAuWzbPGh7AY4rgEvEpkFkLqoacMQSgD AfWbBuBHv3BNxWmh48guVFGyQJ+TKjJA9oxVcZnBTXXgWlLCt7lNeACnxjKNpA11D2vynntRI Aoq+USi/idqaxeBqkLHJ0uGh/i6ff7doRzxUB01s6mk6VT6VqM/rYlLfMj4eQwal6oPO7pk2I PjweoGF+jrUJcn4XRHAjnMTi00soy2W1u2XeYUzoTNEST0SshvJ/u2/7FSK7TdFb6E20+K3It CZVmg81mItbWmKx05PmKZKhdQJTqGWqiN/4Rw9KxSGpAaye8JiZoaqILFRSevXFWPOJSiu22H k+4zTy67YqY6DKDK+KO97yyPTnNDmcSTbule0fltRdr1FbxU4A= X-Spam-Status: No, score=-1.8 required=5.0 tests=BAYES_00, KAM_DMARC_STATUS, KAM_LAZY_DOMAIN_SECURITY, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H4, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=no autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 10 Dec 2021 11:23:42 -0000 On Thu, Dec 9, 2021 at 8:35 PM Adhemerval Zanella via Libc-alpha wrote: > On 09/12/2021 16:19, Florian Weimer wrote: * Adhemerval Zanella via Libc-alpha: > > The change is also not entirely ABI-compatible because existing code on > > x32 depends on the implementation clearing the upper 32 bits, and if new > > code copies around structs, it won't necessary copy the zero bits. > > Afaiu the high-bits clearing is strictly necessary on kABI boundary for > set functions. Some issues indeed might arise if user use timespec > embedded in some function and mix objects built with different glibc > version, but it is similar to 32-bit architectures with mixing time_t > objects. The kernel's 32-bit ABI ignores the upper 32 bits of tv_nsec for structures passed from user space, but zeroes them when returning a timespec to user space. Only x32 is weird here, as it traditionally uses a mix of hte 32-bit user space ABI and the 64-bit user space ABI. Arnd