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 X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 52F61C10F06 for ; Thu, 28 Mar 2019 14:59:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2CEF12075E for ; Thu, 28 Mar 2019 14:59:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726407AbfC1O70 (ORCPT ); Thu, 28 Mar 2019 10:59:26 -0400 Received: from mail-vs1-f66.google.com ([209.85.217.66]:38724 "EHLO mail-vs1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725948AbfC1O7Z (ORCPT ); Thu, 28 Mar 2019 10:59:25 -0400 Received: by mail-vs1-f66.google.com with SMTP id s2so10978259vsi.5; Thu, 28 Mar 2019 07:59:24 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=v4M4YDyunRsROoOZI3ZBVnoRZELo7poRl0NOZ0tJEWg=; b=O5QLv/HII//7oWMcyDMKupZS0vYp38J0CRmCxxw3zqFrOqbg2Clw+fHHmeAYBEfL+A V0mF8uWNWuEAUFBGlaBRpgHSaUjpCH9DIltMRuVbeftVwxfHOriBrcQ8VpSEPEKDuZXN /irjqT7YfBjCC/isxlWnb86JP/MprxVpxAIl61EMGdXlQ0sSilQuiXpKTE4ehZISOg6S KOnieO09eyJOzdJShVvltX8nK3AV33N6jQDHqk8kAoMiBcFfyA8R2QFhLk5xCQeI3a1Y DQKTtxUaZ7YM3kMJSYod2LSn9k8bIWSchK3ojmnGkFVqL4XdGbydRxQ33idyLDrd/8Ji 7Ujg== X-Gm-Message-State: APjAAAUlkPfZApNah/ZkysQwVluvQ29PX0slM/jB8FO9bIicR+e8KVL/ OTH5U+YjkiRdSmN+uNewVNoBZagaB0r07JapT/o= X-Google-Smtp-Source: APXvYqwg/BQSQOJ3gtUqHvmV6vhSKVqMZL76AXxcp4PhbXub54WHNv6KEJArsIrLb147I8qzV9EsVOuS5wrbWwbUGKQ= X-Received: by 2002:a67:ba03:: with SMTP id l3mr18631268vsn.96.1553785164184; Thu, 28 Mar 2019 07:59:24 -0700 (PDT) MIME-Version: 1.0 References: <20190325194319.12850-1-marek.vasut@gmail.com> <20190328141822.GA156243@google.com> In-Reply-To: <20190328141822.GA156243@google.com> From: Geert Uytterhoeven Date: Thu, 28 Mar 2019 15:59:11 +0100 Message-ID: Subject: Re: [PATCH V3] PCI: rcar: Add the initialization of PCIe link in resume_noirq() To: Bjorn Helgaas Cc: Marek Vasut , linux-pci , Kazufumi Ikeda , Gaku Inami , Marek Vasut , Lorenzo Pieralisi , Simon Horman , Wolfram Sang , stable , Geert Uytterhoeven , Phil Edworthy , Wolfram Sang , Linux-Renesas Content-Type: text/plain; charset="UTF-8" Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Hi Bjorn, On Thu, Mar 28, 2019 at 3:18 PM Bjorn Helgaas wrote: > On Mon, Mar 25, 2019 at 08:43:19PM +0100, marek.vasut@gmail.com wrote: > > From: Kazufumi Ikeda > > > > Reestablish the PCIe link very early in the resume process in case it > > went down to prevent PCI accesses from hanging the bus. Such accesses > > can happen early in the PCI resume process, as early as the > > SUSPEND_RESUME_NOIRQ step, thus the link must be reestablished in the > > driver resume_noirq() callback. > > > > Fixes: e015f88c368d ("PCI: rcar: Add support for R-Car H3 to pcie-rcar") > > I'm fine with the fix itself, but since e015f88c368d appeared more > than two years ago in v4.5, the justification for merging this after > the merge window is a little weak. V1 of this fix was posted in November 2017, but IIRC, the series became the target of some bike-shedding... > Is there a more recent change that exposed this problem? The usual > situation is that we merged something during the v5.1 merge window > that caused a regression, and we're now fixing that before v5.1 final. There are several reasons most people couldn't even run suspend/resume cycles on their systems: 1. Early releases of the affected boards came with firmware revisions with non-functional PSCI system suspend, 2. Preparing the PMIC for suspend required ugly assistance from i2cset in userspace, until the Linux driver learned to take care of that itself in v4.18/v4.19. I guess the fix can survive postponing to v5.2, though... Thanks! Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds