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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 58E4DC7EE2C for ; Thu, 25 May 2023 07:46:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239565AbjEYHqx (ORCPT ); Thu, 25 May 2023 03:46:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36508 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238579AbjEYHq3 (ORCPT ); Thu, 25 May 2023 03:46:29 -0400 Received: from mail-pl1-x636.google.com (mail-pl1-x636.google.com [IPv6:2607:f8b0:4864:20::636]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BA7CBE62 for ; Thu, 25 May 2023 00:46:17 -0700 (PDT) Received: by mail-pl1-x636.google.com with SMTP id d9443c01a7336-1ae87bdc452so8260825ad.2 for ; Thu, 25 May 2023 00:46:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1685000777; x=1687592777; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=0zhDQWiK34ot5tBwq359lgKMK077kupVrQ//tKJGcGs=; b=L8VUrlXXazbMEEKp7BaLtOo79zy5ZVMfvbBHxSpKA5ip8JOMiaNJcyCHpMc4AZkgmE QN+Rj8x1klANNV9Rjg8tyj32fBEggzn8lUZ/Qgl8j/bEJYC6ppbqj91vGCpUinACGcd2 TEeUXklqbI3nQyW7mmmE1pnEJuFspmYAWEThCcHb9oA4AFUNxq7JXom0QmERch/fmjhg Xl9XBsHpiCcS02zDhZXCIQJguzX/LnTxFzxHq5iYuTh4LGou+gdD4Wj71c5qDkY4g82h Ic9p6QD2Zn7c22/X1yEs7qs1BU+fIUFozGYNwGIVf6wHqTGV3ZUUhAX8nlSbOXnnth+n aZlw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1685000777; x=1687592777; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=0zhDQWiK34ot5tBwq359lgKMK077kupVrQ//tKJGcGs=; b=NPpuXlDZAFscDJf5iJLmpb/Tit+wQSY4FmceOljm0D0WswNA+PsQQg6/85F6dwuUC8 niyTJY6dhHsxP7NgkAmD7uAZr8GsuFd/Xh9r7ZKIVpRpPrhDuk/R0uIcU92scEykaPVn i2aQcAuMfsQPibIFkhhvT82St/L2xuyamXaACdKgdItKx+9TLhrkty/BgCdVNt1eWSOI hLRR/asimjSmhNWZF7yMHPkbDbf496kne3Tb2e0vV+04Fb8/usiRccC8bybdHo2+LpnL itf8f1sQfwhBOEI9C3v1IaMlsVqzh+/JvhSXV6OoKR8qfrRtwSrmkwObpcX/YOMFG1DL ihFQ== X-Gm-Message-State: AC+VfDwQXHhu4WrpbPSLAjrNpKKFshhvqpmVuHHONBl0RTq8KNqnUBbF DEyB+L5eOanDDSoPrhLM8KSre3rrdTo= X-Google-Smtp-Source: ACHHUZ7avekj4UgOV+S2wBI5qg+WWYhnM4M3EKLxVOCpiiw3WlBbcxf6A5gMATQ0mZL1lx8jbUs/TQ== X-Received: by 2002:a17:902:eb4c:b0:1ac:3605:97ec with SMTP id i12-20020a170902eb4c00b001ac360597ecmr710930pli.62.1685000776961; Thu, 25 May 2023 00:46:16 -0700 (PDT) Received: from sol (194-223-178-180.tpgi.com.au. [194.223.178.180]) by smtp.gmail.com with ESMTPSA id j2-20020a170902da8200b001ae6948b495sm747247plx.22.2023.05.25.00.46.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 25 May 2023 00:46:16 -0700 (PDT) Date: Thu, 25 May 2023 15:46:12 +0800 From: Kent Gibson To: brgl@bgdev.pl Cc: linux-gpio@vger.kernel.org Subject: Re: [BUG] gpiolib: cdev: can't read RELEASED event for last line Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org On Thu, May 25, 2023 at 03:09:26PM +0800, Kent Gibson wrote: > On Thu, May 25, 2023 at 11:09:52AM +0800, Kent Gibson wrote: > > Hi Bart, > > > I can also confirm that receiving the event using a blocking read() on the > fd still works, it is a poll() on the fd followed by a read() that fails. > Hmmm, so it occurred to me that gpionotify does the poll()/read(), so it should exhibit the bug. But no, it doesn't. So it could be my code doing something boneheaded?? Or there is some other variable at play. I'll try to write a test for it with libgpiod and see I can reproduce it. But I might put it on the back burner - this one isn't terribly high priority. Cheers, Kent.