Received: by 2002:a05:6a10:a0d1:0:0:0:0 with SMTP id j17csp1637239pxa; Thu, 20 Aug 2020 16:59:14 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxz4UB2X+pkR4CivQtP5tcFEWhbVsBZA2espOetEeaOGOzw96prQrLcdkK3ySdNmN5NW9c6 X-Received: by 2002:aa7:d9d7:: with SMTP id v23mr381258eds.112.1597967953842; Thu, 20 Aug 2020 16:59:13 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1597967953; cv=none; d=google.com; s=arc-20160816; b=ER3kuzdlbBUJmmvHFwzudwgPuR/wXoQOtOInKelhUHCGiUp0VnaXTlDJ3usRZKWhx9 mJMSSE4wIlUMu+9ttVQH6ke5xv1gjp7TiWgtM4hZklu0PfaHPqC1Bv/0BuUva33xKfHe caeVDJ+GWqxmCTwAVVadpiz3YraU6lbapCvP4HtPo/go8/QsZYVYj2NA7V/g1gRbu2qW 5vXmYt32YFN2bx0yCZptwklG1+IreIrG3hLFcG4r1da0sK5DGcCzXM9D30EAiGMKhszw FvoeW0j9NYJOTzbGogxyit1cCsfqKDlEI5Yw1JB3O8/BdUAN4EKuKgcPkOBc8ZooS+aM abwA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=fSPl4T7yxA6CRARfnCiF1chJ9gpqejz1AF24i+HTCB0=; b=jY2YFHGNWekltGaKQoj7HPurxruiLZURf0xLg/q9fuGIsLTguH9/rHogPIh8IM/Z3E 4ZYZnqzdKT4QT2DMenMyyY7DTbOwTSrp5GoKIbaCobCcqwAoLIm7eeXrptGFCyoVHRLo y9aMHNsfzOafsCp/Y67zYSG1FXHukBPKoRy7w43qtt8L3cfAK+Mp+VUuxZhpfBT+sxtK tA8TidSfBFqjiXUL62IOF8G3z+0T/VnUpFfZ240sa6qZT9aJ497o2uuuqKishf/qkDda bWEozF7RtlJBVcbord+TRZ+1AMyMMnoMF0uA5zLqbMdaTW86W4jupctfZ7SPR98WrpJt yLHQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id s14si19622eju.89.2020.08.20.16.58.50; Thu, 20 Aug 2020 16:59:13 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728009AbgHTWKw (ORCPT + 99 others); Thu, 20 Aug 2020 18:10:52 -0400 Received: from relay1-d.mail.gandi.net ([217.70.183.193]:58227 "EHLO relay1-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727090AbgHTWKv (ORCPT ); Thu, 20 Aug 2020 18:10:51 -0400 X-Originating-IP: 90.66.108.79 Received: from localhost (lfbn-lyo-1-1932-79.w90-66.abo.wanadoo.fr [90.66.108.79]) (Authenticated sender: alexandre.belloni@bootlin.com) by relay1-d.mail.gandi.net (Postfix) with ESMTPSA id F1BF1240003; Thu, 20 Aug 2020 22:10:48 +0000 (UTC) From: Alexandre Belloni To: LKML , Victor Ding Cc: Alexandre Belloni , linux-rtc@vger.kernel.org, Alessandro Zummo Subject: Re: [PATCH v2] rtc: cmos: zero-init wkalrm when reading from CMOS Date: Fri, 21 Aug 2020 00:10:48 +0200 Message-Id: <159796143347.2239022.2687430267906057170.b4-ty@bootlin.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200814191654.v2.1.Iaf7638a2f2a87ff68d85fcb8dec615e41340c97f@changeid> References: <20200814191654.v2.1.Iaf7638a2f2a87ff68d85fcb8dec615e41340c97f@changeid> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 14 Aug 2020 19:17:30 +1000, Victor Ding wrote: > cmos_read_alarm() may leave certain fields of a struct rtc_wkalrm > untouched; therefore, these fields contain garbage if not properly > initialized, leading to inconsistent values when converting into > time64_t. This patch to zero initialize the struct before calling > cmos_read_alarm(). > > Note that this patch is not intended to produce a correct time64_t, it > is only to produce a consistent value. In the case of suspend/resume, a > correct time64_t is not necessary; a consistent value is sufficient to > correctly perform an equality test for t_current_expires and > t_saved_expires. Logic to deduce a correct time64_t is expensive and > hence should be avoided. Applied, thanks! [1/1] rtc: cmos: zero-init wkalrm when reading from CMOS commit: c254bcd7231a3eeafc453f6ee3a483a2e7ff486e Best regards, -- Alexandre Belloni