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=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 760A0C3A5A3 for ; Tue, 27 Aug 2019 14:36:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 48BFE21883 for ; Tue, 27 Aug 2019 14:36:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="t5tRKOdO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729619AbfH0Ogj (ORCPT ); Tue, 27 Aug 2019 10:36:39 -0400 Received: from pandora.armlinux.org.uk ([78.32.30.218]:40330 "EHLO pandora.armlinux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726134AbfH0Ogi (ORCPT ); Tue, 27 Aug 2019 10:36:38 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=vhzf+dZDreIumgSd/qgIOrRav/zwhEMSkCEy/wY4MGU=; b=t5tRKOdOnczH2Hp+z218qFN8+ Q6wWgCMBppznidCK3hI63kFTn7KvDPLsVRYWSRJ3U+i7fZZbXNF6UAbbCIOyaiwNszYvHF/G8g2Rv DstzRoKm5aVvHtIkRA/CD7ixm0rnM4FErN8Mj+JWDFNP5bNXO/rSEaRRi7GqoFU7r9SZj44Co6y9N 1JpRW8mRZFDM+uNGTnD/AKX77SlKBCDbpDhOSz1MVRnrOuHIUIYJiPyYUHmKwD6WGcxlLF8Q0Ka4R NfcQGOM1W0GAQeajTvp09XKvuEpbFkyeHzyNfeIdYnc6PzkRQpeVm0rAbzu5tGXfUvr5gflfWs+C6 v2BBQdvQg==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:38660) by pandora.armlinux.org.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) (envelope-from ) id 1i2caJ-0004zg-HP; Tue, 27 Aug 2019 15:36:35 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.92) (envelope-from ) id 1i2caI-0005om-AW; Tue, 27 Aug 2019 15:36:34 +0100 Date: Tue, 27 Aug 2019 15:36:34 +0100 From: Russell King - ARM Linux admin To: Ulf Hansson Cc: "linux-mmc@vger.kernel.org" , Linux Kernel Mailing List , Linux ARM Subject: Re: Continuous SD IO causes hung task messages Message-ID: <20190827143634.GL13294@shell.armlinux.org.uk> References: <20190827134337.GK13294@shell.armlinux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Aug 27, 2019 at 03:55:23PM +0200, Ulf Hansson wrote: > On Tue, 27 Aug 2019 at 15:43, Russell King - ARM Linux admin > wrote: > > > > Hi, > > > > While dd'ing the contents of a SD card, I get hung task timeout > > messages as per below. However, the dd is making progress. Any > > ideas? > > > > Presumably, mmc_rescan doesn't get a look-in while IO is progressing > > for the card? > > Is it a regression? > > There not much of recent mmc core and mmc block changes, that I can > think of at this point. No idea - I just repaired the SD socket after the D2 line became disconnected, and decided to run that command as a test. > > ARM64 host, Macchiatobin, uSD card. > > What mmc host driver is it? mmci? sdhci-xenon. I'm just trying with one CPU online, then I'll try with two. My suspicion is that there's a problem in the ARM64 arch code where unlocking a mutex doesn't get noticed on other CPUs. Hmm, I thought I'd try bringing another CPU online, but it seems like the ARM64 CPU hotplug code is broken: [ 3552.029689] CPU1: shutdown [ 3552.031099] psci: CPU1 killed. [ 3949.835212] CPU1: failed to come online [ 3949.837753] CPU1: failed in unknown state : 0x0 which means I can only take CPUs down, I can't bring them back online without rebooting. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up According to speedtest.net: 11.9Mbps down 500kbps up