Received: by 2002:ad5:474a:0:0:0:0:0 with SMTP id i10csp1371142imu; Wed, 28 Nov 2018 08:35:16 -0800 (PST) X-Google-Smtp-Source: AFSGD/XpQM6+SzjVidcj2YrOvf1YvioF7de0whkknWfZy2qg7Y5VXkwJiWmDuCohQMkqbECk6OAb X-Received: by 2002:a62:5658:: with SMTP id k85mr27758466pfb.231.1543422916611; Wed, 28 Nov 2018 08:35:16 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1543422916; cv=none; d=google.com; s=arc-20160816; b=ty5WyGw0vOBK5m2jgctLg6vAZp19nGo/I1VcqciI9+qINxBSPfq8xDKqKeUZfKoQIR jfUBwW5shCKgauxzSXqlMiYEFpALRfKhpRN03hSyQmhmWe+stoLpmPzznEG9uQvEaI+o 7kz1v2e9ZTnZgvPObLWYGtKhex5vQfil6ullyxXN4y/UyBCUFccGfQX8k+xwbMY+LBz6 0w6pIt4dZd8u5FtoTkDRAJXTtZqCWBUEK6Gf6/luGt5D4ovWJ+gxyRYRpyOkkr41Oh5B NQLsYE4R3tW5vavDPWtX7oIHTivqzjrjoQ9EAvz7nwq+JALd1d+ihJ+Hq1a2Hqq5imSz rlkA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:date:subject:user-agent:message-id :references:cc:in-reply-to:from:to:content-transfer-encoding :mime-version:dkim-signature; bh=RkGRvaP7pt2XjblG8B+TkNrAtFvT4aT+DbdycSXiqRY=; b=JHNRDZK8BCQb5HHEAeNHnJf9g0lis7BHeQMko+H50Ssm8uFz6kdYUc4OQfNjJEHQgi OYEIqcKguU+y2ZY6AB1OvfyDT23lVB5ITEhhvQPLinTRPrB5wOAQ62H/W+Mo/+sum6/f w/ze2R3gFyQNmxM3W6luxqJ07QJf76I+AT86aD4dFULIcFVSYdOvuQ2ugaYFog0EZmMb ezjMc9XXrcxuheRpaAzw7oiikcaivxAwMqBgNzt9RLy5bHvgkYH6gBmuJzfJJQj8PEDo c6aZVOs3cWks9X7N9GRD6bQIKNTZw2fXIvlpy3XmRZn8uL3I+gV01o5eL4sgP8CFcbFC g8Qg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@chromium.org header.s=google header.b=CUusFWFn; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=chromium.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id y10si7204121plt.406.2018.11.28.08.34.37; Wed, 28 Nov 2018 08:35:16 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@chromium.org header.s=google header.b=CUusFWFn; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=chromium.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729015AbeK2Deu (ORCPT + 99 others); Wed, 28 Nov 2018 22:34:50 -0500 Received: from mail-pl1-f172.google.com ([209.85.214.172]:35332 "EHLO mail-pl1-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727979AbeK2Deu (ORCPT ); Wed, 28 Nov 2018 22:34:50 -0500 Received: by mail-pl1-f172.google.com with SMTP id p8so7345465plo.2 for ; Wed, 28 Nov 2018 08:32:36 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=mime-version:content-transfer-encoding:to:from:in-reply-to:cc :references:message-id:user-agent:subject:date; bh=RkGRvaP7pt2XjblG8B+TkNrAtFvT4aT+DbdycSXiqRY=; b=CUusFWFn10L4e8zfHw1SFyw+HriDiirTehBNME3tq+7ZDq7wAsTXoxKI9b1xycH5w6 LeNoPkC4cLX0vRXgei2i7+7Eo93mGY/5qilACkjCpCqGfGfovI+0pGmVid1/W9GsHYib b52fqWYAQk9OVDkZ9zUtnCqTt+gltKQejhFpU= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:content-transfer-encoding:to:from :in-reply-to:cc:references:message-id:user-agent:subject:date; bh=RkGRvaP7pt2XjblG8B+TkNrAtFvT4aT+DbdycSXiqRY=; b=Syno9Xzt73S3ORy06itVA3EiHb3VmqTpG5J++NGMZskIevIyzU36Ixy8IzTLtGXCl5 mu6Ju/V0CVm49dVJ5kjkIsUo/1Q6S5bYuiDAsi/fFY1TQjxGHM8mq1on701qCw21CvSE MqdBQiyEpDFxaIiIftIfth2rHUczCoscn2heWRYODqOP79UnuJniTXWvE12Imnt+kKHs OBKmqxHw+ed9Lyh+iRW6qsSj+iX1KKsL93nwX3PGGsZOcP5ECbp9G7eODoFdPRuAvmS7 QQRaSE0zPUIYTPv+PpvYSXKg/fvS4hnfHNz+D32TxwZzbBCRXr1xwCdHfdsRSiAvMYwb QF3g== X-Gm-Message-State: AA+aEWZ2JaherwZ/LG2K3r/ceb1t7z8LR4pyDjstfINVe3pQXP4yS/QW dYd5+e0x9g4OWsmJ2FxePe02+g== X-Received: by 2002:a17:902:820d:: with SMTP id x13mr38432898pln.229.1543422756542; Wed, 28 Nov 2018 08:32:36 -0800 (PST) Received: from localhost ([2620:15c:202:1:fed3:9637:a13a:6c15]) by smtp.gmail.com with ESMTPSA id b2sm12517289pfm.3.2018.11.28.08.32.35 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 28 Nov 2018 08:32:35 -0800 (PST) Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable To: Ryan Case From: Stephen Boyd In-Reply-To: Cc: Greg Kroah-Hartman , Jiri Slaby , Evan Green , Doug Anderson , linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org References: <20181127022536.104663-1-ryandcase@chromium.org> <154336440880.88331.11610393939844825622@swboyd.mtv.corp.google.com> <154337068886.88331.5708018437286125025@swboyd.mtv.corp.google.com> Message-ID: <154342275484.88331.11625853632580952641@swboyd.mtv.corp.google.com> User-Agent: alot/0.7 Subject: Re: [PATCH] tty: serial: qcom_geni_serial: Fix softlock Date: Wed, 28 Nov 2018 08:32:34 -0800 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Quoting Ryan Case (2018-11-27 18:37:15) > On Tue, Nov 27, 2018 at 6:04 PM Stephen Boyd wrote: > > > > Quoting Ryan Case (2018-11-27 17:24:44) > > > > > I hope underflow is impossible as well. However, if the hardware did > > > wind up in a strange state I wanted to err on the side of not throwing > > > away data and being able to resume later if things recovered. I can > > > remove the defensive checks if that's the custom, otherwise I'll > > > update the comparison logic accordingly. > > > > Well it looks like impossible code because an unsigned value can't be > > less than zero. So it's not about customs, more about dead code removal. > = > Agreed on the current dead code aspect which is why I offered the > option of updating the comparison logic, but I can just delete it if > you want. Ok, got it.