From patchwork Fri Jan 4 10:32:26 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bartosz Golaszewski X-Patchwork-Id: 1020674 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-gpio-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=bgdev.pl Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=bgdev-pl.20150623.gappssmtp.com header.i=@bgdev-pl.20150623.gappssmtp.com header.b="Jq17G69G"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 43WLhJ6Fpmz9s7T for ; Fri, 4 Jan 2019 21:32:32 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726969AbfADKcb (ORCPT ); Fri, 4 Jan 2019 05:32:31 -0500 Received: from mail-ed1-f66.google.com ([209.85.208.66]:37945 "EHLO mail-ed1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726134AbfADKcb (ORCPT ); Fri, 4 Jan 2019 05:32:31 -0500 Received: by mail-ed1-f66.google.com with SMTP id h50so31392318ede.5 for ; Fri, 04 Jan 2019 02:32:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bgdev-pl.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=c7Tq00l7wWNWOl89qXOwwWszuHIS8h2UPZc8Wsx1Tm4=; b=Jq17G69GlQDs5iEy+pEl7M2w3hhTEjxu0taLEdfdRB7nS//T8Lc/PvnGIYTogwGvg+ E9k54b1VJq57eTnfMeJKXeWT48YSBpms2OTvL9SWEj7zLiXbbmCIcU/Ra3j7z8xzO4rJ +RM3KgEm+5FcOQjDT8KaxaiqtI+28bqznxZmBOmgrR4Ahsti8mJu7N//06GKCFj2wRPT xKqHDN+IK5I43TDHKAIW1BmATPkdJscK6kjZKIhahuLcmUbmwVilV9HA84WA9MaT+viq 7koCKXWxyTLj8TEqMz5HxS+ofzFIDJx+Zlpeg6gggctCZW/Fk4mfl6FY0xwq1r4zhqkw qjiw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=c7Tq00l7wWNWOl89qXOwwWszuHIS8h2UPZc8Wsx1Tm4=; b=sKL8ZquiOM8KCAcEHl04R/z10VQVSis0l72E/JEtWe0EjQpT3DYra8pw6P6zw5QZ9X Jy2xhjSLPvfnWZlnNxX2KBcEF0bbqZa8N2aWgQ0eD0Ln4IsdtMPKhGZjkPOoxOXBAVsQ XxSDUHWeF/d1RJkT3O/24CDaQSFNrTeILLDW8C2zXDJuSlpZ8Nij3/+TUFmrrJk7Vrm5 4kMqmZMvrlmUovYatER+rqdb0reA6+XEc2csulnx4whIX6hTAu6Uy9xJK1/nu9wMmeH8 Pat/RZ1hJUzHgsVtPok5YLod5oV05wVkev/mp/VeemGgwB5Z2Ekev5B0t/pLwMwdy/3H TV9A== X-Gm-Message-State: AA+aEWbMTDGMNwiSzkqRZrl1YGl3tcSZHkcFYvqIlJSOsbh+SHN5Wugd TDqclMEgXBA3jXf1YvSYBFfhbQ== X-Google-Smtp-Source: AFSGD/VDVPBSs7Zs/+ABzNMU3x7dQC8XSn5hDO1vD//VXZC1CONJZG8TO31QWqTx4e+Y2ithtjf4gA== X-Received: by 2002:a50:ad97:: with SMTP id a23mr43655819edd.128.1546597949472; Fri, 04 Jan 2019 02:32:29 -0800 (PST) Received: from debian-brgl.home ([2a01:cb1d:af:5b00:6d6c:8493:1ab5:dad7]) by smtp.gmail.com with ESMTPSA id y26-v6sm13580744ejb.24.2019.01.04.02.32.28 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 04 Jan 2019 02:32:28 -0800 (PST) From: Bartosz Golaszewski To: Linus Walleij Cc: linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, Bartosz Golaszewski Subject: [PATCH] gpiolib: fix line event timestamps for nested irqs Date: Fri, 4 Jan 2019 11:32:26 +0100 Message-Id: <20190104103226.2878-1-brgl@bgdev.pl> X-Mailer: git-send-email 2.19.1 MIME-Version: 1.0 Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org From: Bartosz Golaszewski Nested interrupts run inside the calling thread's context and the top half handler is never called which means that we never read the timestamp. This issue came up when trying to read line events from a gpiochip using regmap_irq_chip for interrupts. Fix it by reading the timestamp from the irq thread function if it's still 0 by the time the second handler is called. Signed-off-by: Bartosz Golaszewski --- drivers/gpio/gpiolib.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 1651d7f0a303..330c52e19b7e 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -828,6 +828,13 @@ static irqreturn_t lineevent_irq_thread(int irq, void *p) /* Do not leak kernel stack to userspace */ memset(&ge, 0, sizeof(ge)); + /* + * We may be running from a nested threaded interrupt in which case + * we didn't get the timestamp from lineevent_irq_handler(). + */ + if (!le->timestamp) + le->timestamp = ktime_get_real_ns(); + ge.timestamp = le->timestamp; if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE